Improved IgG antibody diagnostics of hypersensitivity pneumonitis and pulmonary mycoses by means of newly evaluated serum antibody ranges and frequencies using IgG ImmunoCAP™

Joachim Sennekamp; Emilia Lehmann; Marcus Joest

doi:10.1007/s40629-022-00208-7

Improved IgG antibody diagnostics of hypersensitivity pneumonitis and pulmonary mycoses by means of newly evaluated serum antibody ranges and frequencies using IgG ImmunoCAP™

Sennekamp, Joachim; Lehmann, Emilia; Joest, Marcus 2022-05-17 00:00:00 original article Allergo J Int https://doi.org/10.1007/s40629-022-00208-7 Improved IgG antibody diagnostics of hypersensitivity pneumonitis and pulmonary mycoses by means of newly evaluated serum antibody ranges and frequencies using IgG ImmunoCAP™ Joachim Sennekamp · Emilia Lehmann · Marcus Joest Received: 27 September 2021 / Accepted: 24 January 2022 © The Author(s) 2022 Summary studies, a strongly positive antibody indicates HP or Background The ranges of most human IgG antibod- pulmonary mycosis more likely than a weakly positive ies against avian, microbial, and chemical antigens antibody. It was found that the antigens of the highest between their cut off values and their maximum val- maximum antibody levels—pigeon, budgerigar, par- ues detected by IgG ImmunoCAP™ (Thermo Fisher rot, Aspergillus fumigatus—are the causative agents of Diagnostics, Freiburg, Germany) are not well known the most common immune-mediated lung diseases: in pulmonary immune-mediated disorders. In addi- bird breeder’s lung and pulmonary aspergillosis. Eval- tion, for many antigens it is not yet known how fre- uation of the frequencies of eight major IgG antibodies quently their IgG antibodies appear in patients with of HP revealed the following rates: pigeon 28%, As- these lung diseases. Therefore, we evaluated ranges pergillus fumigatus 25%, budgerigar 23%, Penicillium and frequencies of these IgG antibodies. chrysogenum 11%, Saccharopolyspora rectivirgula 7%, Methods The sera of 47,200 patients with suspected Acremonium kiliense 6%, Aureobasidium pullulans hypersensitivity pneumonitis (HP, extrinsic allergic 5%, and Thermoactinomyces vulgaris 2%. alveolitis) or bronchopulmonary mycoses (mainly al- Conclusion This study is the ﬁrst to evaluate the lergic bronchopulmonary aspergillosis [ABPA]), which ranges not only of avian and Aspergillus fumigatus were examined for 32 various IgG antibodies against antigens, as has been done up to now, but also of birds, bacteria, molds, yeasts, and chemicals using antibodies against 24 other environmental antigens. the IgG ImmunoCAP™ assay, were evaluated retro- Quantiﬁcation of IgG antibodies regarding their spe- spectively. ciﬁc ranges can help to improve the serodiagnostics Results We founda largespreading of thespeciﬁc IgG of immune-mediated lung diseases. In the lower ranges with maximum values from 26 mgA/l for Rhi- ranges IgG antibodies are mainly physiological, while zopus nigricans up to 4640 mgA/l for pigeon. When higher ranges correlate with the mentioned diseases the maximum values in the literature are also taken as HP and ABPA/allergic bronchopulmonary mycoses into account, the ranges of avian antibodies reach val- (ABPM). The determined frequencies of the eight HP ues up to 7280 mgA/l, the ranges of molds and yeasts antibodies can be helpful in establishing HP screening up to 1707 mgA/l, of bacterial thermoactinomycetes tests. up to 206 mgA/l, and of chemicals up to 139 mgA/l. The evaluated antibody ranges of the individual anti- Keywords Antigen-speciﬁc IgG · Enzyme-linked gens can be used to decide whether a detected IgG immunosorbent assay · Extrinsic allergic alveolitis · antibody value is weakly, moderately or strongly posi- Allergic bronchopulmonary aspergillosis · Immune- tive. According to consistent evidence from numerous mediated lung disease Abbreviations J. Sennekamp · M. Joest ABPA Allergic bronchopulmonary aspergillosis Lung and Allergy Centre Bonn, Bonn, Germany ABPM Allergic bronchopulmonary mycosis E. Lehmann () CF Cystic ﬁbrosis Institute for Medical Humanities, University of Bonn, ELISA Enzyme-linked immunosorbent assay Venusberg-Campus 1, 53127 Bonn, Germany HD Hexamethylene diisocyanate emilia.lehmann@ukbonn.de K Improved IgG antibody diagnostics of hypersensitivity pneumonitis and pulmonary mycoses by means of. . . original article HP Hypersensitivity pneumonitis In chronic pulmonary aspergillosis (CPA), strongly IgG Immunoglobulin G positive Aspergillus IgG antibodies in the IgG Immu- MDI Diphenylmethane diisocyanate noCAP™ or IgG-ELISA are typical [3, 4, 13, 14]. In al- TDI Toluene diisocyanate lergic bronchopulmonary mycoses (ABPM), these IgG TMA Trimellith anhydride antibodies can be anything from normal to strongly positive [15]. In healthy individuals these IgG antibodies appear Introduction most commonly in low concentrations [2, 16–19]. IgG antibodies against avian, plant, and chemical These facts demonstrate that immune-mediated antigens, bacteria, molds, and yeasts are increasingly lung diseases are associated with different IgG anti- used today for diagnosing immune-mediated and body levels. Therefore, it is essential for serological infectious lung diseases [1–5]. Originally, the IgG diagnostics to be able to judge whether a measured antibodies were detected by immunoprecipitation value is negative, questionable, weak, medium or techniques, in particular the Ouchterlony test [3, 6]. strong positive. This requires knowledge of the ranges Today, immunoassays, particularly the very sensitive between the cut offs and the maximum limits of these and highly reproducible ImmunoCAP™ assay, are antibodies. widely used [2–8] and recommended for the diag- Looking at the literature, one will discover that only nosis of hypersensitivity pneumonitis (HP), allergic the ranges for IgG antibodies against pigeon, budgeri- bronchopulmonary aspergillosis (ABPA) and other gar, parrot, and Aspergillus fumigatus have been iden- bronchopulmonary mycoses (ABPM) [2, 3, 7, 8]. tiﬁed on IgG ImmunoCAP™ by large quantities of Several studies demonstrated that strongly positive serum samples [6–8, 13, 20]. IgG antibodies in immunoassays correlate better with Sincewehavea largenumber of ImmunoCAP™ the diagnosis of HP than do weakly positive IgG anti- IgG antibody assay results of patients with suspected bodies [7–12]. lung diseases, predominantly HP, pulmonary mycosis, In acute bird-related hypersensitivity pneumoni- and cystic ﬁbrosis (CF), wewereable to analyze the tis and in the recurrent type of chronic bird-related ranges of 32 human IgG antibodies against environ- hypersensitivity pneumonitis, very high and high mental aeroantigens within the IgG ImmunoCAP™. speciﬁc IgG antibody levels are predominantly seen. In addition, we evaluated the frequencies of some However, in the insidious type of chronic HP, lower antibodies in patients with these suspected pul- IgG antibody levels occur, which overlap with the monary diseases. The frequencies of the antibodies levels found in subjects without HP [2]. could be helpful in selecting tests for diagnosis, as Table 1 Medians and percentiles of IgG antibodies from Fig. 1 Antigen Median 75th percentile 90th percentile 95th percentile 97.5th percentile (mgA/l) (mgA/l) (mgA/l) (mgA/l) (mgA/l) Pigeon 25.5 48.3 91.6 200.0 200.0 Budgerigar 39.0 91.0 200.0 200.0 200.0 Canary 42.5 94.0 200.0 200.0 200.0 Parrot 26.5 91.3 200.0 200.0 200.0 Finch 31.5 80.3 196.5 200.0 200.0 Duck 27.0 51.3 73.3 116.8 150.4 Goose 35.5 58.5 118.2 154.3 177.5 Chicken 32.5 74.3 119.1 154.8 177.5 Aspergillus fumigatus 93.0 116.0 146.0 166.0 179.0 Acremonium kiliense 31.0 40.3 56.2 91.2 101.1 Penicillium chrysogenum 90.0 117.3 150.4 173.5 200.0 Fusarium proliferans 61.5 81.3 106.1 118.1 128.6 Cladosporium herbarum 62.0 93.0 143.1 157.4 190.5 Aureobasidium pullulans 32.5 46.3 76.4 96.0 116.1 Alternaria alternata 18.0 25.0 38.3 48.2 70.2 Mucor racemosus 13.0 16.0 24.0 26.0 26.0 n=21 Rhizopus nigricans 12.0 15.0 23.8 26.2 27.1 n=37 Candida albicans 105.0 139.3 195.5 200.0 200.0 Thermoactinomyces vulgaris 38.5 56.0 83.3 115.2 149.1 Sacharopolyspora rectivirgula 20.5 29.3 53.1 97.2 119.9 Improved IgG antibody diagnostics of hypersensitivity pneumonitis and pulmonary mycoses by means of. . . K original article Fig. 1 Graphical representation of 100 individual values (Mucor and Rhizopus with lower numbers) for each 20IgG antibodies from sera loaded undiluted into the ImmunoCAP™ analyzer they give an indication of the probability with which Materials and methods a positive result can be expected. The test results of IgG antibodies of 47,200 patients’ sera with suspected hypersensitivity pneumonitis (ex- trinsic allergic alveolitis), pulmonary mycoses, and cystic ﬁbrosis were evaluated retrospectively. The sera K Improved IgG antibody diagnostics of hypersensitivity pneumonitis and pulmonary mycoses by means of. . . original article had been sent to us together with the submission individuals in a previous study [5]. These control sheet of our laboratory, on which is listed that these persons were not exceptionally exposed to avian and IgG antibodies will be analyzed for the diagnosis of moldy dusts and did not suffer from lung disease, immune-mediated lung diseases. With the exception had no allergies, tumors or chronic inﬂammation. of a few individual cases, the senders did not provide For the antibodies against chemicals (HDI, MDI, TDI, us with information on allergen exposures and diag- TMA, phthalic acid), we applied the cut off of 5 mgA/l noses. recommended by Pronk et al. [21]. For the remaining The test results were recorded anonymously by antibodies, we used the cut offs recommended by the evaluating only the consecutive numbers of the sera manufacturer Thermo Fisher Scientiﬁc. The cut off without awareness of patients’ names. For the values values are shown on Table 2. of Table 1 and Fig. 1, the evaluation of values was The measurement ranges in ImmunoCAP™ ex- performed sequentially starting with the year 2014. tends up to 200 mgA/l. In the period from 2014–2016, The sera had been sent to our laboratory by physi- the patient sera were ﬁlled undiluted into the analyzer. cians from all over Germany (“senders”), mostly by From 2016–2020 sera with values 200 mgA/l were di- pneumologists. The evaluation covers the period of luted 1:10 and—where appropriate—also 1:100 before 2014–2020. Usually several IgG antibodies were tested loading into the analyzer, so values up to 20,000 mgA/l in the serum. Some antibodies (against cockatiel, were recorded. ﬁnch, Aspergillus ﬂavus, Aspergillus glabrum, Tricho- The frequencies of Fig. 2 were determined from 400 derma viride,and Stachybotrys chartarum)were not HP screening tests. For each of the eight antigens, the analyzed over the complete period because they had ratio of antibody levels above the cut off compared been added ﬁrst over the years. to antibody levels below the cut off was calculated Our senders had the option to choose individual as a percentage and the percentages were plotted in IgG antibodies of their choice. Additionally, we of- averticalcolumnchart. fered a HP screening test with a panel of eight IgG antibodies against pigeon, budgerigar, Aspergillus fu- Results migatus, Saccharopolyspora rectivirgula, Thermoacti- nomyces vulgaris, Penicillium chrysogenum, Acremo- Ranges of IgG antibodies nium kiliense (Cephalosporium acremonium) and Au- Levels of IgG antibodies reobasidium pullulans. This most frequently used screening test was re- Fig. 1 shows 100 sequentially measured readings be- quested when there was no anamnestic information tween the cut offs and ≥200 mgA/l of 18 different on exposure to deﬁnite antigens in case of clinical sus- IgG antibodies. Additionally, the levels of Mucor race- picion of HP. 400 screening tests were counted for the mosus (n = 21) and Rhizopus nigricans (n = 37) are individual antigens and their frequencies were evalu- reported with lesser sample numbers. ated in percentages starting with the year 2014. As in many sera with values above 200 mgA/l, no In addition, we offered our senders lists of IgG an- further serum dilution had been performed, only val- tibodies for the diagnostics of allergic bronchopul- ues up to 200 mgA/l were included in Fig. 1.The anti- monary mycoses, farmer’s lung, humidiﬁer’s lung, in- body concentrations above 200 mgA/l are included in door HP, machine worker’s lung, and other rare HP for the > 200 values regardless of whether their sera were their antibody selection. titrated out or not. The IgG antibodies were measured with the Phadia Most high values of > 200 mgA/l appear with the ImmunoCAP™ system (Thermo Fisher Scientiﬁc) us- birds budgerigar, canary, and parrot together with TM ing the Phadia 250 analyzer. The IgG antibodies in similarly low cut off values. However, for antibod- the patients’ sera react in small vessels, called CAPs, ies against molds, the yeast Candida albicans and with the corresponding antigens, bound to the walls thermophilic bacteria, the cut-offs are more different. of the CAPs. By means of an enzyme-labeled anti-IgG As a supplement to Fig. 1,Table 1 presents the me- the amount of human IgG antibodies bound to the dian values and the 75th, 90th, 95th, and 97.5th per- antigens is quantitatively measured by ﬂuorescence centiles of the antibody values. optics [7]. In order to be able to assess whether an IgG an- IgG antibodies against the antigens we studied tibody is to be classiﬁed as weak, medium or strong are also detectable in healthy people, usually in low positive, the range within which the IgG antibody is amounts which are not disease-relevant. In medical known to ﬂuctuate must be known for each antigen. diagnostics of immune-mediated human diseases, the This is the range between the cut off and the maxi- IgG antibodies usually exceed thresholds, so-called mum value. “cut offs”. These cut offs are usually determined using Maximal antibody values and ranges of variation of the percentiles in sera from healthy persons [16, 19]. We IgG antibodies had selected the frequently used 95% percentile to determine the cut offs for IgG antibodies against the Since maximum values in large serum collectives have above-mentioned antigens in sera from 20 healthy so far only been determined for a few antigens, as Improved IgG antibody diagnostics of hypersensitivity pneumonitis and pulmonary mycoses by means of. . . K original article Table 2 Evaluated maximum values of all detected IgG antibodies, quantities of analyses, published maximum values of other authors, and ranges of these antibodies. We consider the range values in bold letters to be applicable for diagnostics nowadays; the others still require further evaluation. No ranges are given for antigens with less than 20 antibodies above the cut off Antigen Cut off Maximum Number of analyses Published maximum Range (mgA/l) value (n = positive results values (mgA/l) (mgA/l) (mgA/l) with less than 100 [Reference] detected antibodies) Avian Antigens Pigeon 16 4640 27 225 7280 [8] 16–7280 Serum, feathers and droppings Budgerigar 8 2770 25 783 3540 [8] 8–3540 Serum, feathers and droppings a + Cockatiel 10 1550 230 (n = 76) – 10–1550 Droppings Canary 11 1440 756 – 11–1440 Feathers Parrot 10 1150 885 1230 [8] 10–1230 Serum, feathers and droppings Finch 8 790 735 – 8–790 Feathers Chicken 14 423 1665 – 14–423 Feathers Goose 11 880 2550 174 [23] 11–880 Feathers Duck 9 209 2435 97 [23] 9–209 Feathers Molds Aspergillus fumigatus 64 1120 31 035 1707 [20] 64–1707 a + Aspergillus niger 45 409 482 (n = 88) – 45–409 a + Aspergillus ﬂavus 61 274 42 (n = 11) – – Penicillium chrysogenum 64 850 20 435 – 64–850 b + Penicillium glabrum 21 176 43 (n =7) – – Acremonium kiliense 23 1390 19 245 – 23–1390 Aureobasidium pullulans 22 187 19 233 – 22–187 Cladosporium herbarum 37 453 631 – 37–453 Alternaria alternata 12 118 626 – 12–118 Fusarium proliferatum 46 477 2537 – 46–477 b + Trichoderma viride 17 83 147 (n = 13) – – b + Stachybotrys atra (chartarum) 11 43 163 (n = 12) – – a + Mucor racemosus 8 26 331 (n = 22) – 8–26 a + Rhizopus nigricans 11 28 353 (n = 38) – 11–28 Bacteria Saccharopolyspora rectivir- 13 206 19 430 – 13–206 gula (Micropolyspora faeni) Thermoactinomyces vulgaris 28 200 19 332 – 28–200 Candida albicans 70 504 467 – 70–504 Yeasts a d + Saccharomyces cerevisiae 17 249 72 (n =7) – – c d + Chemicals HDI 5 87 252 (n = 21) – 5–87 (Hexamethylene diisocyanate) c d + MDI 5 139 252 (n = 21) – 5–139 (Diphenyl methane diisocyanate) c + TDI 5 47 252 (n = 25) – 5–47 (Toluene diisocyanate) c + TMA 5 38 121 (n =8) – – (Trimellitic acid) c + Phthalic acid 5 26 112 (n =9) – – In house cut-off [5] Cut-off recommended by Phadia ImmunoCAP IgG Kit Cut-off from [21] Sera from patients with deﬁnite HP Most sera were tested for several antibodies K Improved IgG antibody diagnostics of hypersensitivity pneumonitis and pulmonary mycoses by means of. . . original article Fig. 2 Frequencies of the Pigeon 28% 72% IgG antibodies of the HP Aspergillus fumigatus 25% 75% screening test. Evaluation of 400 screening tests Budgerigar 23% 77% posive Penicillium chrysogenum 11% 89% Saccharopolyspora rect. 7% 93% negave Acremonium kiliense 6% 94% Aureobasidium pullulans 5% 95% Thermoacnomyces vulgaris 2% 98% outlined in the introduction, we evaluated maximum Maximal antibody values and ranges of variation of values for additional IgG antibodies and present these the IgG antibodies for a total of 32 aeroantigens in Table 2. The highest maximum values in our sera with more The ranges of IgG antibodies against different antigens than 1000 mgA/l are reached by the antibodies against (Table 2) vary considerably from 8–26 mgA/l for Mu- birds (pigeon, budgerigar, cockatiel, canary, and par- cor racemosus to 16–7280 mgA/l for pigeon (Table 2). rot) and molds (Aspergillus fumigatus and Acremo- This exceeds by far the ranges of the cut offs (e.g. for nium kiliense). Similar values for pigeon, budgerigar, chemical antigens 5 mgA/l on the lower end and for parrot, and Aspergillus fumigatus were reported in the Candida albicans 70 mgA/l on the upper end). Knowl- literature. These similarities between our values and edge of these ranges could improve the interpretation the values of references provide a good basis for the of IgG results for each individual antigen. Sera with ranges derived from them. 200 mgA/l values should be titrated by means of addi- The antibodies against bacteria and chemicals lie tional dilution analyses. on a considerably lower level. Higher antibody levels for pigeon, budgerigar and It is noteworthy that the ranges of these IgG an- parrot than ours were reported by Lopata et al. ([8]; tibodies are extremely different for the various anti- Table 2). Additionally, three high values of IgG an- gens, with a maximum range for pigeon antibodies tibodies against pigeon serum on ImmunoCAP™ in (16–7280 mgA/l) to the narrowest range for Rhizopus the range between 3500 mgA/l and 4000 mgA/l were nigricans (11–26 mgA/l). reported by van Hoeyveld et al. for patients affected by pigeon breeder’s lung [6]. Koschel et al. examined IgG antibodies against Frequencies of IgG antibodies goose and duck feathers in the IgG ImmunoCAP™ in The frequencies of the eight antibodies of our hyper- patients with proved feather duvet lungs; they found sensitivity screening test are shown in Fig. 2.The an- maximum values of 174 mgA/l for goose feathers and tibodies against avian antigens and Aspergillus fumi- 97 mgA/l for duck feathers [22]. gatus are most prevalent, whereas antibodies against For Aspergillus fumigatus,Page et al. identiﬁed Thermoactinomyces vulgaris are least frequent. a maximum value of 1707 mgA/l ([20]; Table 2), while van Hoeyveld et al. and Fujiuchi et al. reported lower maximum values around 1000 mgA/l [6, 13]. Discussion For other molds we could not ﬁnd represen- tative maximum values of analyses done by IgG Levels of IgG antibodies ImmunoCAP™ in literature for pulmonary mycoses The antibody levels differ considerably (Fig. 1). For and HP. Thus, the maximum values reported here instance, 16% of the budgerigar antibodies exceed (Table 2) will be of particular scientiﬁc importance. 200 mgA/l but no Alternaria antibody reaches this Apart from Penicillium chrysogenum and Acremonium level. Therefore, a uniform scoring of these IgG anti- kiliense, the IgG maximum values and the ranges are bodies, as for IgE antibodies with a universal cut off considerably lower than for Aspergillus fumigatus. at 0.35 kU/l, is not applicable. Each antigen-speciﬁc However, some of our maximum values are likely to IgG antibody requires a unique cut off value. For our be too low because the quantities of sera examined region, Central Europe, cut offs have been evaluated are small (Aspergillus niger, Aspergillus ﬂavus, Penicil- by Kränke, Pronk, Sennekamp, and Raulf [5, 16, 19, lium glabrum, Trichoderma viride, Stachybotrys atra, 21]. Since Raulf’s results were not yet available at the Mucor racemosus, Rhizopus nigricans). beginning of our evaluation, we used our own cut The bacteria (thermoactinomycetes) Saccharopoly- offs [5] as well as for additional antigens those rec- spora rectivirgula and Thermoactinomyces vulgaris in- ommended by the manufacturer and those of Pronk duce only HP (farmer’s lung, humidiﬁer’s lung, bagas- et al. for the chemical antigens [21]. sosis), not any other diseases [23, 24]. The maximum values of their antibodies around 200 mgA/l are mod- Improved IgG antibody diagnostics of hypersensitivity pneumonitis and pulmonary mycoses by means of. . . K original article erately high. For these we could not ﬁnd representa- Frequencies of IgG antibodies tive maximum values in literature. The yeast Candida albicans is one of the antigens In analyzing the frequencies of the antibodies, we causing the seldomly diagnosed allergic bronchopul- have assessed the eight antigens of our HP screen- monary mycoses (ABPM). Besides other criteria, the ing test (Fig. 2), which was done exclusively in sera serologic diagnosis is done by speciﬁc Candida IgE from patients with suspected HP. and IgG antibodies [25]. The most frequent IgG antibodies of Fig. 2 are the Candida albicans is also a rare cause of HP [23, 26]. antiavian IgGs. Epidemiological studies have consis- However, we found no Candida ImmunoCAP™ IgG tently shown that bird fancier’s lung is the most com- analyses in these patients in literature. mon HP-entity, accounting for 40% of all HPs in the The maximum IgG value of Saccharomyces cere- United States and in Germany [24, 30, 31]. Similarly, visiae in Table 2 marked with (249 mgA/l) belongs the antibodies against the avian antigens, especially to a HP patient with occupational inhalation of dry against pigeons and budgerigars, reach the highest yeast powder [27]. The food-induced Saccharomyces maximum values and the highest ranges in this study cerevisiae IgG antibodies occur with lower levels in (Table 2). Therefore, the antibodies against the avian Crohn’s and in celiac disease [27]. antigens are highly relevant for diagnostics of HP. For the isocyanate IgG antibodies additional Im- Aspergillus fumigatus IgG antibodies are present in munoCAP™ values were reported in literature [28]. different HP entities but also play a role in pulmonary The highest values were for TDI (toluene diisocyanate) mycoses (infectious and allergic), which are—taken 8 mgA/l, for MDI (diphenylmethane diisocyanate) together—more common than HP [3, 4, 24, 33]. 13 mgA/l, and for HDI (hexamethylene diisocyanate) The antibodies against the bacterial antigens Sac- 15 mgA/l. We obtained some particularly high IgG charopolyspora rectivirgula and Thermoactinomyces antibody values in our sera which belonged to pa- vulgaris occur least frequently in our examined pa- tients with documented HP [27, 29]. This supports tients (Fig. 2). They are the main antigens in farmer’s the phenomenon reported for other antigens in that lung, which has become rare in Germany with the high levels of IgG are typical for patients with acute change of storing hay in silages and better methods HP [7–12]. of drying the hay [23]. Sometimes thermoactino- If a uniform scale were chosen for all aerogenic IgG mycetes are the trigger of humidiﬁer lung, also a rare antibodies, for example from 5–10,000 mgA/l, these type of HP. We could not ﬁnd any human infections values of our isocyanate patient from 42 mgA/l up to or colonisations caused by these thermobacteria in 87 mgA/l (Table 2) would be classiﬁed as low. In con- the literature. trast, using the HDI isocyanate range of 5–87 mgA/l The determined frequencies of the eight HP anti- and the TDI range of 5–47 mgA/l in Table 2,theyare bodies can be helpful for rational IgG antibody di- judged to be high-titer antibodies indicating probable agnostics and in establishing new HP screening tests HP. [34]. An effective way to assess the value of an IgG anti- body is to add a semiquantitative rating to the mea- IgG antibodies in other conditions sured value, for example with the categories: nega- tive—questionable—weak—moderate—strong [5, 16]. Aspergillus fumigatus, Candida albicans,and Acremo- Another way to judge a reading is to add a scale of the nium kiliense not only cause allergies in humans, but range of variation to it. For this purpose, authors used infections or colonisations of mucus membranes too, logarithmic graduations [3, 6, 13]. which also induce IgG antibodies [3, 4, 35, 36]. Penicil- The top IgG maximum value levels of pigeon lium chrysogenum antibodies can be elevated as a re- (7280 mgA/l), budgerigar (3540 mgA/l), parrot sult of cross-reactivity with Aspergilli even without the (1230 mgA/l), and Aspergillus fumigatus (1707 mgA/l) patient having had contact with the Penicillium fun- (Table 2) are seen in the most common immune- gus [37, 38]. mediated lung diseases: in bird-related HP [23, 24, In addition, these antibodies related either to infec- 30, 31] and in the two most common Aspergillus- tion, colonisation or cross-reaction are also likely to related lung diseases: ABPA with high prevalences increase the median values (Table 1;[19]). IgG anti- (e.g. in Germany up to 150 cases per 100,000 peo- bodies are particularly frequently induced by Candida ple [32]) and chronic pulmonary aspergillosis (CPA) yeasts, colonizing the mucous membranes of the oral with a prevalence of 2.5/100,000 people. The number cavity, intestine, vagina, and anus [39, 40]. of CPA cases worldwide was estimated to be at least Aspergillus fumigatus grows particularly in tuber- 4.8 million [1, 33]. Obviously, these antigens with high culous caverns, bronchiectasis and on the bronchial maximum speciﬁc IgG values are more potent to in- mucosa of patients with cystic ﬁbrosis [3, 4, 36]. Such duce extrinsic immune-mediated lung diseases than colonisations are asymptomatic and usually there is antigens which only induce a weaker IgG response. no need for treatment. One can expect that among the subjects in large control collectives for the evaluation of cut offs there K Improved IgG antibody diagnostics of hypersensitivity pneumonitis and pulmonary mycoses by means of. . . original article Table 3 Maximum, median, and mean values of IgG antibodies in healthy persons evaluated by Kränke et al. [16], Raulf et al. [19], and Tan et al. [17] IgG antibody against Kränke et al. Raulf et al. Tan et al. n=48 n = 121 n = 120 Maximum value Median Maximum value Median Mean value (mgA/l) (mgA/l) (mgA/l) (mgA/l) (mgA/l) Avian Pigeon 53 2 43 9 12 Antigens Serum, feathers and droppings Budgerigar 26 3 18 3 6 Serum, feathers and droppings Canary 18 5 14 2 – Feathers Parrot 41 12 32 4 14 Serum, feathers and droppings Chicken – – 27 6 – Feathers Goose – – 19 5 – Feathers Duck – – 15 4 – Feathers Molds Aspergillus fumigatus 86 14 726 21 31 Penicillium chrysogenum (notatum) 42 8 143 14 – Acremonium kiliense – – 39 5 – Aureobasidium pullulans 47 7 26 3 5 Cladosporium herbarum 72 12 65 11 – Alternaria alternata – – 37 3 – Fusarium proliferatum – – 92 9 – Trichoderma viride – – 3 – Stachybotrys atra – 53 2 – Mucor racemosus – 12 3 – Rhizopus nigricans – – 14 2 – Bacteria Saccharopolyspora rectivirgula (Microp- 15 3 14 2 – olyspora faeni) Thermoactinomyces vulgaris 47 11 30 7 – Yeasts Candida albicans 201 33 112 26 47 Chemicals Isocyanates – 7 1 – are such asymptomatic individuals with IgG antibod- IgG antibodies in healthy persons ies, especially in large control collectives. They com- plicate the determination of the cut off values, espe- The maximum values in healthy persons in Austria cially for Candida albicans, Aspergilli, and the cross- [16]and in Germany ([19]; Table 3) are markedly lower reacting Penicillia molds [16, 19]. than in our sera from patients with suspected lung dis- Other antigens, in particular the avian proteins, ease (Table 2). Particularly high maximum values in the thermoactinomycetes Saccharopolyspora rectivir- these healthy people however were recorded for Peni- gula and Thermoactinomyces vulgaris, Aureobasidium cillium chrysogenum, Aspergillus fumigatus,and Can- pullulans, Stachybotrys atra and the chemicals (Ta- dida albicans (Table 2). As mentioned above, these ble 2), do not colonize human mucous membranes germs can infect human tissues or colonize mucous and cause no human infections. This might be the membranes in clinically asymptomatic persons [36, reason for their low cut off levels (Table 2). Posi- 39, 40]. tive IgG antibodies against these antigens are there- For the ﬁrst two collectives of healthy individuals fore better qualiﬁed for diagnosing immune-mediated in Table 3, Kränke et al. and Raulf et al. [16, 19]had lung diseases. Otherwise, Aspergilli, Penicillia, Acre- selected only healthy individuals who had no obvious monium kiliense,and Candida albicans IgG antibod- contact with birds, molds, and bacteria. Tan et al. [17] ies have a broader screening potential for diverse res- did not perform this selection. piratory diseases including infectious disorders of the lung. Diagnostic interpretation of the IgG antibodies Healthy individuals exposed to antigens may well also have clearly positive IgG antibodies to these antigens Improved IgG antibody diagnostics of hypersensitivity pneumonitis and pulmonary mycoses by means of. . . K original article in their sera, so that the diagnosis of these lung dis- the evaluated antigens, especially Aspergillus fumiga- eases cannot be made on the basis of antibody levels tus, Penicillium chrysogenum,and Candida albicans, alone. Only together with the other diagnostic criteria the cut-offs differ considerably in the cited studies [5, of HP [41–43], pulmonary mycoses [1, 3, 4, 15, 43, 44], 16, 19]. This has to be taken into account when in- CF [36, 37, 43] or pulmonary infections [3, 4, 14, 39] terpreting our results. Fortunately, there were major the IgG antibodies are a valuable tool for diagnosing differences only for these three antigens mentioned these diseases. above, whereas the cut offs of nearly all other anti- The most speciﬁc for the diagnostics of HP are the gens lay close together. IgG antibodies against avian antigens, thermoacti- nomycetes (Saccharopolyspora rectivirgula and Ther- Conclusion moactinomyces vulgaris), Aureobasidium pullulans, Stachybotrys atra, and the chemicals (Table 2)be- This study is the ﬁrst to evaluate the ranges of the cause these antigens do not colonize human mucous most relevant IgG antibodies against inhalant anti- membranes and cause no human infections. gens using ImmunoCAP™. Knowledge of these dif- Otherwise, IgG antibodies against Aspergilli, Peni- ferent ranges may be helpful to graduate an IgG an- cillia and Candida albicans have a broader screening tibody reading as a questionable, weak, medium or potential for diverse lung diseases as ABPA, ABPM, strong positive IgG antibody. A grading of the speciﬁc and infectious disorders of the lung, and sometimes IgGs is of clinical relevance, as HP and pulmonary also indicate cross-reactions with other microorgan- mycoses, particularly CPA, are more likely with higher isms [3, 4, 23, 36, 37, 39, 40]. IgG antibodies. IgG antibodies against birds, thermoactinomycetes and chemicals are the most speciﬁc for diagnosing Limitations HP. Mold and yeast antibodies are less speciﬁc be- This is a retrospective study where we had no in- cause they also occur in bronchopulmonary mycoses, ﬂuence on the choice of antibody selection by the in infections, cystic ﬁbrosis, mucosal colonisations senders. A further disadvantage of our study is cer- and can be the result of cross-reactions with other tainly, that we have not titered the maximum values microorganisms. ≥200 mgA/l in the period 2014–2016. Taken together, we consider the evaluated IgG anti- The most frequently analyzed IgG antibodies against body ranges and antibody frequencies described here antigens as pigeon, budgerigar, Aspergillus fumigatus, may help to improve serologic diagnostics of these Penicillium chrysogenum, Acremonium kiliense, Au- immune-mediated lung diseases. reobasidium pullulans, Saccharopolyspora rectivirgula Acknowledgements We are grateful to Sabine Schmidt, and Thermoactinomyces vulgaris had a greater chance Brigitte Hüneke, Manuela Schmitz-Gerhardt and Barbara of getting high maximum levels than the less frequent Kläge for their perfect analyses of the IgG antibodies. analyzed other antibodies (Table 2). This also ap- Funding Open Access funding enabled and organized by plies to the maximum values of the literature. There Projekt DEAL. are more studies of IgG antibodies against the anti- gens pigeon [6–8, 12]and Aspergillus fumigatus [6, Declarations 13, 15–20] and thus higher chances for particularly high values than for other antigens as goose and duck Conﬂict of interest J. Sennekamp, E. Lehmann and M. Joest feathers [22, 34], isocyanates [21, 28, 29]or Saccha- declare that they have no competing interests. romyces cerevisiae [27]. For the maximum values and Ethical standards This is a retrospective study with anony- ranges of these rare antibodies further evaluations mized data. will be required in future. Concerning the frequencies, we would have liked Open Access This article is licensed under a Creative Com- mons Attribution 4.0 International License, which permits to evaluate more than the described eight antibod- use, sharing, adaptation, distribution and reproduction in ies of the HP screening test. However, an evaluation any medium or format, as long as you give appropriate credit attempt revealed extremely high frequencies of anti- to the original author(s) and the source, provide a link to bodies against birds and bed feathers. On the “visible” the Creative Commons licence, and indicate if changes were birds (meaning anamnestically recognizable), the hit made. The images or other third party material in this article rate is of course higher than on the “invisible” bacte- are included in the article’s Creative Commons licence, unless ria and molds. Therefore, such an evaluation would indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and distort the results. your intended use is not permitted by statutory regulation or An additional limitation of our study is the depen- exceeds the permitted use, you will need to obtain permis- dence of our results on the chosen cut-offs. The de- sion directly from the copyright holder. To view a copy of this cision to include only IgG values over the individual licence, visit http://creativecommons.org/licenses/by/4.0/. cut-offs of each antigen was taken because gradua- tion is only needed above the cut offs; below the cut offs all values are graded as negative. For some of K Improved IgG antibody diagnostics of hypersensitivity pneumonitis and pulmonary mycoses by means of. . . original article 19. Raulf M, Joest M, Sander I, Hoffmeyer F, Nowak D, References Ochmann U, et al. Update of reference values for IgG antibodies against typical antigens of hypersensitivity 1. Denning DW, Cadranel J, Beigelman-Aubry C, Ader F, pneumonitis. AllergoJInt. 2019;28:192–203. Chakrabarti A, Blot S, et al. Chronic pulmonary aspergillo- 20. Page ID, Richardson MD, Denning DW. Comparison of six sis; rationale and clinical guidelines for diagnosis and aspergillus speciﬁc IgG assays for the diagnosis of chronic management. EurRespirJ.2016;47:45–68. pulmonaryaspergillosis(CPA). JInfect. 2016;72:240–9. 2. Shirai T, Tanino Y, Nikaido T, Takaku Y, Hashimoto S, 21. Pronk A, Preller L, Raulf-Heimsoth M, et al. Respiratory Taguchi Y, et al. Screening and diagnosis of acute symptoms, sensitization, and exposure—response rela- and chronic bird-related hypersensitivity pneumonitis tionships in spray painters exposed to isocyanates. Am J by serum IgG and IgA antibodies to bird antigens with RespirCritCareMed. 2007;176:1090–7. ImmunoCAP. AllergolInt. 2021;70:208–14. 22. Koschel D, Lützkendorf L, Wiedemann B, Höffken G. Anti- 3. Page ID, Richardson M, Denning DW. Antibody testing in gen-speciﬁc IgG antibodies in feather duvet lung. Eur J Clin aspergillosis—quovadis? MedMycol. 2015;53:417–39. Invest. 2010;40:797–8032. 4. Richardson MD, Page ID. Aspergillus serology: have we 23. Sennekamp J. Extrinsicallergicalveolitis—hypersensitivity arrivedyet? MedMycol. 2017;55:48–55. pneumonitis. Munich,Orlando: Dustri-Verlag;2004. 5. Sennekamp J, Lehmann E, Joest M. Work related extrinsic 24. Costabel U, Miyazaki Y, Pardo A, Koschel D, Bonella F, allergicalveolitis. ASUInt. 2015;50:38–52. SpagnoloP,etal. Hypersensitivitypneumonitis. NatRevDis 6. Van Hoeyveld E, Dupont L, Bossuyt X. Quantiﬁcation of Primers. 2020;6:65. IgG antibodies to aspergillus fumigatus and pigeon anti- 25. Chowdhary A, Agarwal K, Kathuria S, Gaur SN, Rand- gens by ImmunoCAP technology: an alternative to the hawa HS, Meis JF. Allergic bronchopulmonary mycosis due precipitationtechnique? ClinChem. 2006;52:1785–93. to fungi other than aspergillus: a global overview. Crit Rev 7. McSharry C, Dye GM, Ismail T, Anderson K, Spiers EM, Microbiol. 2014;40:30–48. BoydG.Quantifyingserumantibodyinbirdfanciers’hyper- 26. SerranoC,TorregoA,LoosliA,ValeroA,PicadoC.Hypersen- sensitivitypneumonitis. BMCPulmMed. 2006;6:16. sitivity pneumonitis after exposure to Candida spp. Arch 8. Lopata AL, Schinkel M, Potter PC, Jeebhay MF, Hashemi C, Bronconeumol. 2010;46:275–7. Johansson SGO, et al. Qualitative and quantitative eval- 27. Gernhold M, Sennekamp J. Exogen-allergische Alveoli- uation of bird-speciﬁc IgG antibodies. Int Arch Allergy tis durch Backhefe (Saccharomyces cerevisiae). AL. Immunol. 2004;134:173–8. 2010;33:577–80. 9. Erkinjuntti-Pekkanen R, Reiman M, Kokkarinen JI, Tuki- 28. Baur X, Fischer A, Budnik LT. Spotlight on the diagnosis of ainen HO, Terho EO. IgG antibodies, chronic bronchitis, extrinsic allergic alveolitis (hypersensitivity pneumonitis). and pulmonary function values in farmer’s lung patients JOccupMedToxicol. 2015;10:15. andmatchedcontrols. Allergy. 1999;54:1181–7. 29. Schreiber J, Knolle J, Sennekamp J, Schulz KT, Hahn JU, 10. Lewis C, McSharry C, Anderson K, Speekenbrink A, Ke- Hering KG, et al. Subacute occupational hypersensitivity meny DM, Durnin S, et al. Quantifying serum antibody pneumonitis due low-level exposure to diisocyanates in class and subclass responses by enzyme immunoassay in asecretary. EurRespirJ.2008;32:807–11. humidiﬁer-relateddisease. ClinExpAllergy. 1991;21:601–7. 30. Liebetrau G, Bergmann KC. Morbiditäts- und Mortalität- 11. Woge MJ, Ryu JH, Moua T. Diagnostic implications of szahlen für die exogen-allergische Alveolitis (EAA). AL. positiveavian serology in suspectedhypersensitivity pneu- 1994;17:61–4. monitis. RespirMed. 2017;129:173–8. 31. Fernández Pérez ER, Swigris JJ, Forssén AV, Tourin O, 12. Khan S, Chowdhury SR, Ghosh S, Sengupta A, Ramasub- Solomon JJ, Huie TJ, et al. Identifying an inciting antigen is ban S, Sen D. Quantitation of avian IgG antibodies with associated with improved survival in patients with chronic clinico-radiological tests in the diagnosis of bird fancier’s hypersensitivitypneumonitis. Chest. 2013;144:1644–51. hypersensitivitypneumonitis. PulmoFace. 2015;15:48–54. 32. Joest M, Sennekamp J. Allergische bronchopulmonale 13. Fujiuchi S, Fujita H, Suzuki H, Doushita K, Kuroda H, Aspergillose (ABPA) und andere allergische bronchopul- Takahashi M, et al. Evaluation of a quantitative serological monale Mykosen (ABPM). Munich, Orlando: Dustri- assayfordiagnosingchronicpulmonaryaspergillosis. JClin Verlag;2020. Microbiol. 2016;54:1496–9. 33. Denning DW, Pleuvry A, Cole D. Global burden of allergic 14. YuQ,HeJ,XingB,LiX,QianH,ZhangH,etal. Potentialvalue bronchopulmonary aspergillosis with asthma and its com- of serum aspergillus IgG antibody detection in invasive plication chronic pulmonary aspergillosis in adults. Med and chronic pulmonary aspergillosis. BMC Pulm Med. Mycol. 2013;51:361–70. 2020;20:89. 34. Sennekamp J, Lehmann E. Optimierte IgG-Antikörper- 15. Agarwal R, Dua D, Choudhary H, Aggarwal AN, Sehgal IS, diagnostik der Bettfedern-Alveolitis mittels EAA-Suchtest. Dhooria S, et al. Role of Aspergillus fumigatus-speciﬁc IgG Pneumologie. 2015;69:638–44. in diagnosis and monitoring treatment response in allergic 35. Júnior MC, de Moraes Arantes A, Silva HM, Costa CR, bronchopulmonaryaspergillosis. Mycoses. 2017;60:33–9. Silva MRR, et al. Acremonium kiliense: case report 16. Kränke B, Woltsche M, Woltsche-Kahr I, Aberer W. IgG- and review of published studies. Mycopathologia. Antikörper gegen EAA-speziﬁsche Umweltantigene. AL. 2013;176:417–21. 2001;24:145–54. 36. EschenhagenP,GrehnC,SchwarzC.Prospectiveevaluation 17. Tan YH, Ngan CCL, Huang SW, Loo CM, Low SY. Speciﬁc of aspergillus fumigatus speciﬁc IgG in patients with cystic serum immunoglobulin G (IgG) levels against antigens im- ﬁbrosis. FrontCellInfectMicrobiol. 2021;10:602836. plicated in hypersensitivity pneumonitis in asymptomatic 37. Brouwer J. Cross-reactivity between aspergillus fumi- individuals. AnnAcadMedSingap. 2019;48:36–8. gatus and penicillium. Int Arch Allergy Immunol. 18. Makkonen K, Viitala KI, Parkkila S, Niemelä O. Serum 1996;110:166–73. IgG and IgE antibodies against mold-derivedantigens in 38. Vojdani A. Cross-reactivity of aspergillus, penicillium, and patiens with symptoms of hypersensitivity. Clin ChimActa. stachybotrys antigens using afﬁnity-puriﬁed antibodies 2001;305:89–98. andimmunoassay. ArchEnvironHealth. 2004;59:256–65. Improved IgG antibody diagnostics of hypersensitivity pneumonitis and pulmonary mycoses by means of. . . K original article 39. Richardson JP, Moyes DL. Adaptive immune responses to 43. Samson MH, Vestergaard JM, Knudsen CS, Kolstad HA. Candidaalbicansinfections. Virulence. 2015;6:327–37. Serum levels of IgG antibodies against aspergillus fumi- 40. HuertasB,PrietoD,PitarchA,GilC,PlaJ,Díez-OrejasR,etal. gatus and the risk of hypersensitivity pneumonitis and Serum antibody proﬁle during colonization of the mouse other interstitial lung diseases. Scand J Clin Lab Invest. gutbyCandidaalbicans. JProteomeRes. 2017;15:335–45. 2021;81:451–3. 41. Petnak T, Moua T. Exposure assessment in hypersensitiv- 44. Barton RC, Hobson RP, Denton M, Peckham D, Brownlee K, ity pneumonitis: a comprehensive review and proposed Conway S, et al. Serologic diagnosis of allergic bron- screeningquestionnaire. ERJOpenRes. 2020;6:230–2020. chopulmonary aspergillosis in patients with cystic ﬁbrosis 42. Quirce S, Vandenplas O, Campo P, Cruz MJ, de Blay F, through the detection of immunoglobulin G to aspergillus Koschel D, et al. Occupational hypersensitivity pneumoni- fumigatus. DiagnMicrobiolInfectDis. 2008;62:287–91. tis: anEAACIpositionpaper. Allergy. 2016;71:765–79. 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DOI: 10.1007/s40629-022-00208-7
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Abstract

original article Allergo J Int https://doi.org/10.1007/s40629-022-00208-7 Improved IgG antibody diagnostics of hypersensitivity pneumonitis and pulmonary mycoses by means of newly evaluated serum antibody ranges and frequencies using IgG ImmunoCAP™ Joachim Sennekamp · Emilia Lehmann · Marcus Joest Received: 27 September 2021 / Accepted: 24 January 2022 © The Author(s) 2022 Summary studies, a strongly positive antibody indicates HP or Background The ranges of most human IgG antibod- pulmonary mycosis more likely than a weakly positive ies against avian, microbial, and chemical antigens antibody. It was found that the antigens of the highest between their cut off values and their maximum val- maximum antibody levels—pigeon, budgerigar, par- ues detected by IgG ImmunoCAP™ (Thermo Fisher rot, Aspergillus fumigatus—are the causative agents of Diagnostics, Freiburg, Germany) are not well known the most common immune-mediated lung diseases: in pulmonary immune-mediated disorders. In addi- bird breeder’s lung and pulmonary aspergillosis. Eval- tion, for many antigens it is not yet known how fre- uation of the frequencies of eight major IgG antibodies quently their IgG antibodies appear in patients with of HP revealed the following rates: pigeon 28%, As- these lung diseases. Therefore, we evaluated ranges pergillus fumigatus 25%, budgerigar 23%, Penicillium and frequencies of these IgG antibodies. chrysogenum 11%, Saccharopolyspora rectivirgula 7%, Methods The sera of 47,200 patients with suspected Acremonium kiliense 6%, Aureobasidium pullulans hypersensitivity pneumonitis (HP, extrinsic allergic 5%, and Thermoactinomyces vulgaris 2%. alveolitis) or bronchopulmonary mycoses (mainly al- Conclusion This study is the ﬁrst to evaluate the lergic bronchopulmonary aspergillosis [ABPA]), which ranges not only of avian and Aspergillus fumigatus were examined for 32 various IgG antibodies against antigens, as has been done up to now, but also of birds, bacteria, molds, yeasts, and chemicals using antibodies against 24 other environmental antigens. the IgG ImmunoCAP™ assay, were evaluated retro- Quantiﬁcation of IgG antibodies regarding their spe- spectively. ciﬁc ranges can help to improve the serodiagnostics Results We founda largespreading of thespeciﬁc IgG of immune-mediated lung diseases. In the lower ranges with maximum values from 26 mgA/l for Rhi- ranges IgG antibodies are mainly physiological, while zopus nigricans up to 4640 mgA/l for pigeon. When higher ranges correlate with the mentioned diseases the maximum values in the literature are also taken as HP and ABPA/allergic bronchopulmonary mycoses into account, the ranges of avian antibodies reach val- (ABPM). The determined frequencies of the eight HP ues up to 7280 mgA/l, the ranges of molds and yeasts antibodies can be helpful in establishing HP screening up to 1707 mgA/l, of bacterial thermoactinomycetes tests. up to 206 mgA/l, and of chemicals up to 139 mgA/l. The evaluated antibody ranges of the individual anti- Keywords Antigen-speciﬁc IgG · Enzyme-linked gens can be used to decide whether a detected IgG immunosorbent assay · Extrinsic allergic alveolitis · antibody value is weakly, moderately or strongly posi- Allergic bronchopulmonary aspergillosis · Immune- tive. According to consistent evidence from numerous mediated lung disease Abbreviations J. Sennekamp · M. Joest ABPA Allergic bronchopulmonary aspergillosis Lung and Allergy Centre Bonn, Bonn, Germany ABPM Allergic bronchopulmonary mycosis E. Lehmann () CF Cystic ﬁbrosis Institute for Medical Humanities, University of Bonn, ELISA Enzyme-linked immunosorbent assay Venusberg-Campus 1, 53127 Bonn, Germany HD Hexamethylene diisocyanate emilia.lehmann@ukbonn.de K Improved IgG antibody diagnostics of hypersensitivity pneumonitis and pulmonary mycoses by means of. . . original article HP Hypersensitivity pneumonitis In chronic pulmonary aspergillosis (CPA), strongly IgG Immunoglobulin G positive Aspergillus IgG antibodies in the IgG Immu- MDI Diphenylmethane diisocyanate noCAP™ or IgG-ELISA are typical [3, 4, 13, 14]. In al- TDI Toluene diisocyanate lergic bronchopulmonary mycoses (ABPM), these IgG TMA Trimellith anhydride antibodies can be anything from normal to strongly positive [15]. In healthy individuals these IgG antibodies appear Introduction most commonly in low concentrations [2, 16–19]. IgG antibodies against avian, plant, and chemical These facts demonstrate that immune-mediated antigens, bacteria, molds, and yeasts are increasingly lung diseases are associated with different IgG anti- used today for diagnosing immune-mediated and body levels. Therefore, it is essential for serological infectious lung diseases [1–5]. Originally, the IgG diagnostics to be able to judge whether a measured antibodies were detected by immunoprecipitation value is negative, questionable, weak, medium or techniques, in particular the Ouchterlony test [3, 6]. strong positive. This requires knowledge of the ranges Today, immunoassays, particularly the very sensitive between the cut offs and the maximum limits of these and highly reproducible ImmunoCAP™ assay, are antibodies. widely used [2–8] and recommended for the diag- Looking at the literature, one will discover that only nosis of hypersensitivity pneumonitis (HP), allergic the ranges for IgG antibodies against pigeon, budgeri- bronchopulmonary aspergillosis (ABPA) and other gar, parrot, and Aspergillus fumigatus have been iden- bronchopulmonary mycoses (ABPM) [2, 3, 7, 8]. tiﬁed on IgG ImmunoCAP™ by large quantities of Several studies demonstrated that strongly positive serum samples [6–8, 13, 20]. IgG antibodies in immunoassays correlate better with Sincewehavea largenumber of ImmunoCAP™ the diagnosis of HP than do weakly positive IgG anti- IgG antibody assay results of patients with suspected bodies [7–12]. lung diseases, predominantly HP, pulmonary mycosis, In acute bird-related hypersensitivity pneumoni- and cystic ﬁbrosis (CF), wewereable to analyze the tis and in the recurrent type of chronic bird-related ranges of 32 human IgG antibodies against environ- hypersensitivity pneumonitis, very high and high mental aeroantigens within the IgG ImmunoCAP™. speciﬁc IgG antibody levels are predominantly seen. In addition, we evaluated the frequencies of some However, in the insidious type of chronic HP, lower antibodies in patients with these suspected pul- IgG antibody levels occur, which overlap with the monary diseases. The frequencies of the antibodies levels found in subjects without HP [2]. could be helpful in selecting tests for diagnosis, as Table 1 Medians and percentiles of IgG antibodies from Fig. 1 Antigen Median 75th percentile 90th percentile 95th percentile 97.5th percentile (mgA/l) (mgA/l) (mgA/l) (mgA/l) (mgA/l) Pigeon 25.5 48.3 91.6 200.0 200.0 Budgerigar 39.0 91.0 200.0 200.0 200.0 Canary 42.5 94.0 200.0 200.0 200.0 Parrot 26.5 91.3 200.0 200.0 200.0 Finch 31.5 80.3 196.5 200.0 200.0 Duck 27.0 51.3 73.3 116.8 150.4 Goose 35.5 58.5 118.2 154.3 177.5 Chicken 32.5 74.3 119.1 154.8 177.5 Aspergillus fumigatus 93.0 116.0 146.0 166.0 179.0 Acremonium kiliense 31.0 40.3 56.2 91.2 101.1 Penicillium chrysogenum 90.0 117.3 150.4 173.5 200.0 Fusarium proliferans 61.5 81.3 106.1 118.1 128.6 Cladosporium herbarum 62.0 93.0 143.1 157.4 190.5 Aureobasidium pullulans 32.5 46.3 76.4 96.0 116.1 Alternaria alternata 18.0 25.0 38.3 48.2 70.2 Mucor racemosus 13.0 16.0 24.0 26.0 26.0 n=21 Rhizopus nigricans 12.0 15.0 23.8 26.2 27.1 n=37 Candida albicans 105.0 139.3 195.5 200.0 200.0 Thermoactinomyces vulgaris 38.5 56.0 83.3 115.2 149.1 Sacharopolyspora rectivirgula 20.5 29.3 53.1 97.2 119.9 Improved IgG antibody diagnostics of hypersensitivity pneumonitis and pulmonary mycoses by means of. . . K original article Fig. 1 Graphical representation of 100 individual values (Mucor and Rhizopus with lower numbers) for each 20IgG antibodies from sera loaded undiluted into the ImmunoCAP™ analyzer they give an indication of the probability with which Materials and methods a positive result can be expected. The test results of IgG antibodies of 47,200 patients’ sera with suspected hypersensitivity pneumonitis (ex- trinsic allergic alveolitis), pulmonary mycoses, and cystic ﬁbrosis were evaluated retrospectively. The sera K Improved IgG antibody diagnostics of hypersensitivity pneumonitis and pulmonary mycoses by means of. . . original article had been sent to us together with the submission individuals in a previous study [5]. These control sheet of our laboratory, on which is listed that these persons were not exceptionally exposed to avian and IgG antibodies will be analyzed for the diagnosis of moldy dusts and did not suffer from lung disease, immune-mediated lung diseases. With the exception had no allergies, tumors or chronic inﬂammation. of a few individual cases, the senders did not provide For the antibodies against chemicals (HDI, MDI, TDI, us with information on allergen exposures and diag- TMA, phthalic acid), we applied the cut off of 5 mgA/l noses. recommended by Pronk et al. [21]. For the remaining The test results were recorded anonymously by antibodies, we used the cut offs recommended by the evaluating only the consecutive numbers of the sera manufacturer Thermo Fisher Scientiﬁc. The cut off without awareness of patients’ names. For the values values are shown on Table 2. of Table 1 and Fig. 1, the evaluation of values was The measurement ranges in ImmunoCAP™ ex- performed sequentially starting with the year 2014. tends up to 200 mgA/l. In the period from 2014–2016, The sera had been sent to our laboratory by physi- the patient sera were ﬁlled undiluted into the analyzer. cians from all over Germany (“senders”), mostly by From 2016–2020 sera with values 200 mgA/l were di- pneumologists. The evaluation covers the period of luted 1:10 and—where appropriate—also 1:100 before 2014–2020. Usually several IgG antibodies were tested loading into the analyzer, so values up to 20,000 mgA/l in the serum. Some antibodies (against cockatiel, were recorded. ﬁnch, Aspergillus ﬂavus, Aspergillus glabrum, Tricho- The frequencies of Fig. 2 were determined from 400 derma viride,and Stachybotrys chartarum)were not HP screening tests. For each of the eight antigens, the analyzed over the complete period because they had ratio of antibody levels above the cut off compared been added ﬁrst over the years. to antibody levels below the cut off was calculated Our senders had the option to choose individual as a percentage and the percentages were plotted in IgG antibodies of their choice. Additionally, we of- averticalcolumnchart. fered a HP screening test with a panel of eight IgG antibodies against pigeon, budgerigar, Aspergillus fu- Results migatus, Saccharopolyspora rectivirgula, Thermoacti- nomyces vulgaris, Penicillium chrysogenum, Acremo- Ranges of IgG antibodies nium kiliense (Cephalosporium acremonium) and Au- Levels of IgG antibodies reobasidium pullulans. This most frequently used screening test was re- Fig. 1 shows 100 sequentially measured readings be- quested when there was no anamnestic information tween the cut offs and ≥200 mgA/l of 18 different on exposure to deﬁnite antigens in case of clinical sus- IgG antibodies. Additionally, the levels of Mucor race- picion of HP. 400 screening tests were counted for the mosus (n = 21) and Rhizopus nigricans (n = 37) are individual antigens and their frequencies were evalu- reported with lesser sample numbers. ated in percentages starting with the year 2014. As in many sera with values above 200 mgA/l, no In addition, we offered our senders lists of IgG an- further serum dilution had been performed, only val- tibodies for the diagnostics of allergic bronchopul- ues up to 200 mgA/l were included in Fig. 1.The anti- monary mycoses, farmer’s lung, humidiﬁer’s lung, in- body concentrations above 200 mgA/l are included in door HP, machine worker’s lung, and other rare HP for the > 200 values regardless of whether their sera were their antibody selection. titrated out or not. The IgG antibodies were measured with the Phadia Most high values of > 200 mgA/l appear with the ImmunoCAP™ system (Thermo Fisher Scientiﬁc) us- birds budgerigar, canary, and parrot together with TM ing the Phadia 250 analyzer. The IgG antibodies in similarly low cut off values. However, for antibod- the patients’ sera react in small vessels, called CAPs, ies against molds, the yeast Candida albicans and with the corresponding antigens, bound to the walls thermophilic bacteria, the cut-offs are more different. of the CAPs. By means of an enzyme-labeled anti-IgG As a supplement to Fig. 1,Table 1 presents the me- the amount of human IgG antibodies bound to the dian values and the 75th, 90th, 95th, and 97.5th per- antigens is quantitatively measured by ﬂuorescence centiles of the antibody values. optics [7]. In order to be able to assess whether an IgG an- IgG antibodies against the antigens we studied tibody is to be classiﬁed as weak, medium or strong are also detectable in healthy people, usually in low positive, the range within which the IgG antibody is amounts which are not disease-relevant. In medical known to ﬂuctuate must be known for each antigen. diagnostics of immune-mediated human diseases, the This is the range between the cut off and the maxi- IgG antibodies usually exceed thresholds, so-called mum value. “cut offs”. These cut offs are usually determined using Maximal antibody values and ranges of variation of the percentiles in sera from healthy persons [16, 19]. We IgG antibodies had selected the frequently used 95% percentile to determine the cut offs for IgG antibodies against the Since maximum values in large serum collectives have above-mentioned antigens in sera from 20 healthy so far only been determined for a few antigens, as Improved IgG antibody diagnostics of hypersensitivity pneumonitis and pulmonary mycoses by means of. . . K original article Table 2 Evaluated maximum values of all detected IgG antibodies, quantities of analyses, published maximum values of other authors, and ranges of these antibodies. We consider the range values in bold letters to be applicable for diagnostics nowadays; the others still require further evaluation. No ranges are given for antigens with less than 20 antibodies above the cut off Antigen Cut off Maximum Number of analyses Published maximum Range (mgA/l) value (n = positive results values (mgA/l) (mgA/l) (mgA/l) with less than 100 [Reference] detected antibodies) Avian Antigens Pigeon 16 4640 27 225 7280 [8] 16–7280 Serum, feathers and droppings Budgerigar 8 2770 25 783 3540 [8] 8–3540 Serum, feathers and droppings a + Cockatiel 10 1550 230 (n = 76) – 10–1550 Droppings Canary 11 1440 756 – 11–1440 Feathers Parrot 10 1150 885 1230 [8] 10–1230 Serum, feathers and droppings Finch 8 790 735 – 8–790 Feathers Chicken 14 423 1665 – 14–423 Feathers Goose 11 880 2550 174 [23] 11–880 Feathers Duck 9 209 2435 97 [23] 9–209 Feathers Molds Aspergillus fumigatus 64 1120 31 035 1707 [20] 64–1707 a + Aspergillus niger 45 409 482 (n = 88) – 45–409 a + Aspergillus ﬂavus 61 274 42 (n = 11) – – Penicillium chrysogenum 64 850 20 435 – 64–850 b + Penicillium glabrum 21 176 43 (n =7) – – Acremonium kiliense 23 1390 19 245 – 23–1390 Aureobasidium pullulans 22 187 19 233 – 22–187 Cladosporium herbarum 37 453 631 – 37–453 Alternaria alternata 12 118 626 – 12–118 Fusarium proliferatum 46 477 2537 – 46–477 b + Trichoderma viride 17 83 147 (n = 13) – – b + Stachybotrys atra (chartarum) 11 43 163 (n = 12) – – a + Mucor racemosus 8 26 331 (n = 22) – 8–26 a + Rhizopus nigricans 11 28 353 (n = 38) – 11–28 Bacteria Saccharopolyspora rectivir- 13 206 19 430 – 13–206 gula (Micropolyspora faeni) Thermoactinomyces vulgaris 28 200 19 332 – 28–200 Candida albicans 70 504 467 – 70–504 Yeasts a d + Saccharomyces cerevisiae 17 249 72 (n =7) – – c d + Chemicals HDI 5 87 252 (n = 21) – 5–87 (Hexamethylene diisocyanate) c d + MDI 5 139 252 (n = 21) – 5–139 (Diphenyl methane diisocyanate) c + TDI 5 47 252 (n = 25) – 5–47 (Toluene diisocyanate) c + TMA 5 38 121 (n =8) – – (Trimellitic acid) c + Phthalic acid 5 26 112 (n =9) – – In house cut-off [5] Cut-off recommended by Phadia ImmunoCAP IgG Kit Cut-off from [21] Sera from patients with deﬁnite HP Most sera were tested for several antibodies K Improved IgG antibody diagnostics of hypersensitivity pneumonitis and pulmonary mycoses by means of. . . original article Fig. 2 Frequencies of the Pigeon 28% 72% IgG antibodies of the HP Aspergillus fumigatus 25% 75% screening test. Evaluation of 400 screening tests Budgerigar 23% 77% posive Penicillium chrysogenum 11% 89% Saccharopolyspora rect. 7% 93% negave Acremonium kiliense 6% 94% Aureobasidium pullulans 5% 95% Thermoacnomyces vulgaris 2% 98% outlined in the introduction, we evaluated maximum Maximal antibody values and ranges of variation of values for additional IgG antibodies and present these the IgG antibodies for a total of 32 aeroantigens in Table 2. The highest maximum values in our sera with more The ranges of IgG antibodies against different antigens than 1000 mgA/l are reached by the antibodies against (Table 2) vary considerably from 8–26 mgA/l for Mu- birds (pigeon, budgerigar, cockatiel, canary, and par- cor racemosus to 16–7280 mgA/l for pigeon (Table 2). rot) and molds (Aspergillus fumigatus and Acremo- This exceeds by far the ranges of the cut offs (e.g. for nium kiliense). Similar values for pigeon, budgerigar, chemical antigens 5 mgA/l on the lower end and for parrot, and Aspergillus fumigatus were reported in the Candida albicans 70 mgA/l on the upper end). Knowl- literature. These similarities between our values and edge of these ranges could improve the interpretation the values of references provide a good basis for the of IgG results for each individual antigen. Sera with ranges derived from them. 200 mgA/l values should be titrated by means of addi- The antibodies against bacteria and chemicals lie tional dilution analyses. on a considerably lower level. Higher antibody levels for pigeon, budgerigar and It is noteworthy that the ranges of these IgG an- parrot than ours were reported by Lopata et al. ([8]; tibodies are extremely different for the various anti- Table 2). Additionally, three high values of IgG an- gens, with a maximum range for pigeon antibodies tibodies against pigeon serum on ImmunoCAP™ in (16–7280 mgA/l) to the narrowest range for Rhizopus the range between 3500 mgA/l and 4000 mgA/l were nigricans (11–26 mgA/l). reported by van Hoeyveld et al. for patients affected by pigeon breeder’s lung [6]. Koschel et al. examined IgG antibodies against Frequencies of IgG antibodies goose and duck feathers in the IgG ImmunoCAP™ in The frequencies of the eight antibodies of our hyper- patients with proved feather duvet lungs; they found sensitivity screening test are shown in Fig. 2.The an- maximum values of 174 mgA/l for goose feathers and tibodies against avian antigens and Aspergillus fumi- 97 mgA/l for duck feathers [22]. gatus are most prevalent, whereas antibodies against For Aspergillus fumigatus,Page et al. identiﬁed Thermoactinomyces vulgaris are least frequent. a maximum value of 1707 mgA/l ([20]; Table 2), while van Hoeyveld et al. and Fujiuchi et al. reported lower maximum values around 1000 mgA/l [6, 13]. Discussion For other molds we could not ﬁnd represen- tative maximum values of analyses done by IgG Levels of IgG antibodies ImmunoCAP™ in literature for pulmonary mycoses The antibody levels differ considerably (Fig. 1). For and HP. Thus, the maximum values reported here instance, 16% of the budgerigar antibodies exceed (Table 2) will be of particular scientiﬁc importance. 200 mgA/l but no Alternaria antibody reaches this Apart from Penicillium chrysogenum and Acremonium level. Therefore, a uniform scoring of these IgG anti- kiliense, the IgG maximum values and the ranges are bodies, as for IgE antibodies with a universal cut off considerably lower than for Aspergillus fumigatus. at 0.35 kU/l, is not applicable. Each antigen-speciﬁc However, some of our maximum values are likely to IgG antibody requires a unique cut off value. For our be too low because the quantities of sera examined region, Central Europe, cut offs have been evaluated are small (Aspergillus niger, Aspergillus ﬂavus, Penicil- by Kränke, Pronk, Sennekamp, and Raulf [5, 16, 19, lium glabrum, Trichoderma viride, Stachybotrys atra, 21]. Since Raulf’s results were not yet available at the Mucor racemosus, Rhizopus nigricans). beginning of our evaluation, we used our own cut The bacteria (thermoactinomycetes) Saccharopoly- offs [5] as well as for additional antigens those rec- spora rectivirgula and Thermoactinomyces vulgaris in- ommended by the manufacturer and those of Pronk duce only HP (farmer’s lung, humidiﬁer’s lung, bagas- et al. for the chemical antigens [21]. sosis), not any other diseases [23, 24]. The maximum values of their antibodies around 200 mgA/l are mod- Improved IgG antibody diagnostics of hypersensitivity pneumonitis and pulmonary mycoses by means of. . . K original article erately high. For these we could not ﬁnd representa- Frequencies of IgG antibodies tive maximum values in literature. The yeast Candida albicans is one of the antigens In analyzing the frequencies of the antibodies, we causing the seldomly diagnosed allergic bronchopul- have assessed the eight antigens of our HP screen- monary mycoses (ABPM). Besides other criteria, the ing test (Fig. 2), which was done exclusively in sera serologic diagnosis is done by speciﬁc Candida IgE from patients with suspected HP. and IgG antibodies [25]. The most frequent IgG antibodies of Fig. 2 are the Candida albicans is also a rare cause of HP [23, 26]. antiavian IgGs. Epidemiological studies have consis- However, we found no Candida ImmunoCAP™ IgG tently shown that bird fancier’s lung is the most com- analyses in these patients in literature. mon HP-entity, accounting for 40% of all HPs in the The maximum IgG value of Saccharomyces cere- United States and in Germany [24, 30, 31]. Similarly, visiae in Table 2 marked with (249 mgA/l) belongs the antibodies against the avian antigens, especially to a HP patient with occupational inhalation of dry against pigeons and budgerigars, reach the highest yeast powder [27]. The food-induced Saccharomyces maximum values and the highest ranges in this study cerevisiae IgG antibodies occur with lower levels in (Table 2). Therefore, the antibodies against the avian Crohn’s and in celiac disease [27]. antigens are highly relevant for diagnostics of HP. For the isocyanate IgG antibodies additional Im- Aspergillus fumigatus IgG antibodies are present in munoCAP™ values were reported in literature [28]. different HP entities but also play a role in pulmonary The highest values were for TDI (toluene diisocyanate) mycoses (infectious and allergic), which are—taken 8 mgA/l, for MDI (diphenylmethane diisocyanate) together—more common than HP [3, 4, 24, 33]. 13 mgA/l, and for HDI (hexamethylene diisocyanate) The antibodies against the bacterial antigens Sac- 15 mgA/l. We obtained some particularly high IgG charopolyspora rectivirgula and Thermoactinomyces antibody values in our sera which belonged to pa- vulgaris occur least frequently in our examined pa- tients with documented HP [27, 29]. This supports tients (Fig. 2). They are the main antigens in farmer’s the phenomenon reported for other antigens in that lung, which has become rare in Germany with the high levels of IgG are typical for patients with acute change of storing hay in silages and better methods HP [7–12]. of drying the hay [23]. Sometimes thermoactino- If a uniform scale were chosen for all aerogenic IgG mycetes are the trigger of humidiﬁer lung, also a rare antibodies, for example from 5–10,000 mgA/l, these type of HP. We could not ﬁnd any human infections values of our isocyanate patient from 42 mgA/l up to or colonisations caused by these thermobacteria in 87 mgA/l (Table 2) would be classiﬁed as low. In con- the literature. trast, using the HDI isocyanate range of 5–87 mgA/l The determined frequencies of the eight HP anti- and the TDI range of 5–47 mgA/l in Table 2,theyare bodies can be helpful for rational IgG antibody di- judged to be high-titer antibodies indicating probable agnostics and in establishing new HP screening tests HP. [34]. An effective way to assess the value of an IgG anti- body is to add a semiquantitative rating to the mea- IgG antibodies in other conditions sured value, for example with the categories: nega- tive—questionable—weak—moderate—strong [5, 16]. Aspergillus fumigatus, Candida albicans,and Acremo- Another way to judge a reading is to add a scale of the nium kiliense not only cause allergies in humans, but range of variation to it. For this purpose, authors used infections or colonisations of mucus membranes too, logarithmic graduations [3, 6, 13]. which also induce IgG antibodies [3, 4, 35, 36]. Penicil- The top IgG maximum value levels of pigeon lium chrysogenum antibodies can be elevated as a re- (7280 mgA/l), budgerigar (3540 mgA/l), parrot sult of cross-reactivity with Aspergilli even without the (1230 mgA/l), and Aspergillus fumigatus (1707 mgA/l) patient having had contact with the Penicillium fun- (Table 2) are seen in the most common immune- gus [37, 38]. mediated lung diseases: in bird-related HP [23, 24, In addition, these antibodies related either to infec- 30, 31] and in the two most common Aspergillus- tion, colonisation or cross-reaction are also likely to related lung diseases: ABPA with high prevalences increase the median values (Table 1;[19]). IgG anti- (e.g. in Germany up to 150 cases per 100,000 peo- bodies are particularly frequently induced by Candida ple [32]) and chronic pulmonary aspergillosis (CPA) yeasts, colonizing the mucous membranes of the oral with a prevalence of 2.5/100,000 people. The number cavity, intestine, vagina, and anus [39, 40]. of CPA cases worldwide was estimated to be at least Aspergillus fumigatus grows particularly in tuber- 4.8 million [1, 33]. Obviously, these antigens with high culous caverns, bronchiectasis and on the bronchial maximum speciﬁc IgG values are more potent to in- mucosa of patients with cystic ﬁbrosis [3, 4, 36]. Such duce extrinsic immune-mediated lung diseases than colonisations are asymptomatic and usually there is antigens which only induce a weaker IgG response. no need for treatment. One can expect that among the subjects in large control collectives for the evaluation of cut offs there K Improved IgG antibody diagnostics of hypersensitivity pneumonitis and pulmonary mycoses by means of. . . original article Table 3 Maximum, median, and mean values of IgG antibodies in healthy persons evaluated by Kränke et al. [16], Raulf et al. [19], and Tan et al. [17] IgG antibody against Kränke et al. Raulf et al. Tan et al. n=48 n = 121 n = 120 Maximum value Median Maximum value Median Mean value (mgA/l) (mgA/l) (mgA/l) (mgA/l) (mgA/l) Avian Pigeon 53 2 43 9 12 Antigens Serum, feathers and droppings Budgerigar 26 3 18 3 6 Serum, feathers and droppings Canary 18 5 14 2 – Feathers Parrot 41 12 32 4 14 Serum, feathers and droppings Chicken – – 27 6 – Feathers Goose – – 19 5 – Feathers Duck – – 15 4 – Feathers Molds Aspergillus fumigatus 86 14 726 21 31 Penicillium chrysogenum (notatum) 42 8 143 14 – Acremonium kiliense – – 39 5 – Aureobasidium pullulans 47 7 26 3 5 Cladosporium herbarum 72 12 65 11 – Alternaria alternata – – 37 3 – Fusarium proliferatum – – 92 9 – Trichoderma viride – – 3 – Stachybotrys atra – 53 2 – Mucor racemosus – 12 3 – Rhizopus nigricans – – 14 2 – Bacteria Saccharopolyspora rectivirgula (Microp- 15 3 14 2 – olyspora faeni) Thermoactinomyces vulgaris 47 11 30 7 – Yeasts Candida albicans 201 33 112 26 47 Chemicals Isocyanates – 7 1 – are such asymptomatic individuals with IgG antibod- IgG antibodies in healthy persons ies, especially in large control collectives. They com- plicate the determination of the cut off values, espe- The maximum values in healthy persons in Austria cially for Candida albicans, Aspergilli, and the cross- [16]and in Germany ([19]; Table 3) are markedly lower reacting Penicillia molds [16, 19]. than in our sera from patients with suspected lung dis- Other antigens, in particular the avian proteins, ease (Table 2). Particularly high maximum values in the thermoactinomycetes Saccharopolyspora rectivir- these healthy people however were recorded for Peni- gula and Thermoactinomyces vulgaris, Aureobasidium cillium chrysogenum, Aspergillus fumigatus,and Can- pullulans, Stachybotrys atra and the chemicals (Ta- dida albicans (Table 2). As mentioned above, these ble 2), do not colonize human mucous membranes germs can infect human tissues or colonize mucous and cause no human infections. This might be the membranes in clinically asymptomatic persons [36, reason for their low cut off levels (Table 2). Posi- 39, 40]. tive IgG antibodies against these antigens are there- For the ﬁrst two collectives of healthy individuals fore better qualiﬁed for diagnosing immune-mediated in Table 3, Kränke et al. and Raulf et al. [16, 19]had lung diseases. Otherwise, Aspergilli, Penicillia, Acre- selected only healthy individuals who had no obvious monium kiliense,and Candida albicans IgG antibod- contact with birds, molds, and bacteria. Tan et al. [17] ies have a broader screening potential for diverse res- did not perform this selection. piratory diseases including infectious disorders of the lung. Diagnostic interpretation of the IgG antibodies Healthy individuals exposed to antigens may well also have clearly positive IgG antibodies to these antigens Improved IgG antibody diagnostics of hypersensitivity pneumonitis and pulmonary mycoses by means of. . . K original article in their sera, so that the diagnosis of these lung dis- the evaluated antigens, especially Aspergillus fumiga- eases cannot be made on the basis of antibody levels tus, Penicillium chrysogenum,and Candida albicans, alone. Only together with the other diagnostic criteria the cut-offs differ considerably in the cited studies [5, of HP [41–43], pulmonary mycoses [1, 3, 4, 15, 43, 44], 16, 19]. This has to be taken into account when in- CF [36, 37, 43] or pulmonary infections [3, 4, 14, 39] terpreting our results. Fortunately, there were major the IgG antibodies are a valuable tool for diagnosing differences only for these three antigens mentioned these diseases. above, whereas the cut offs of nearly all other anti- The most speciﬁc for the diagnostics of HP are the gens lay close together. IgG antibodies against avian antigens, thermoacti- nomycetes (Saccharopolyspora rectivirgula and Ther- Conclusion moactinomyces vulgaris), Aureobasidium pullulans, Stachybotrys atra, and the chemicals (Table 2)be- This study is the ﬁrst to evaluate the ranges of the cause these antigens do not colonize human mucous most relevant IgG antibodies against inhalant anti- membranes and cause no human infections. gens using ImmunoCAP™. Knowledge of these dif- Otherwise, IgG antibodies against Aspergilli, Peni- ferent ranges may be helpful to graduate an IgG an- cillia and Candida albicans have a broader screening tibody reading as a questionable, weak, medium or potential for diverse lung diseases as ABPA, ABPM, strong positive IgG antibody. A grading of the speciﬁc and infectious disorders of the lung, and sometimes IgGs is of clinical relevance, as HP and pulmonary also indicate cross-reactions with other microorgan- mycoses, particularly CPA, are more likely with higher isms [3, 4, 23, 36, 37, 39, 40]. IgG antibodies. IgG antibodies against birds, thermoactinomycetes and chemicals are the most speciﬁc for diagnosing Limitations HP. Mold and yeast antibodies are less speciﬁc be- This is a retrospective study where we had no in- cause they also occur in bronchopulmonary mycoses, ﬂuence on the choice of antibody selection by the in infections, cystic ﬁbrosis, mucosal colonisations senders. A further disadvantage of our study is cer- and can be the result of cross-reactions with other tainly, that we have not titered the maximum values microorganisms. ≥200 mgA/l in the period 2014–2016. Taken together, we consider the evaluated IgG anti- The most frequently analyzed IgG antibodies against body ranges and antibody frequencies described here antigens as pigeon, budgerigar, Aspergillus fumigatus, may help to improve serologic diagnostics of these Penicillium chrysogenum, Acremonium kiliense, Au- immune-mediated lung diseases. reobasidium pullulans, Saccharopolyspora rectivirgula Acknowledgements We are grateful to Sabine Schmidt, and Thermoactinomyces vulgaris had a greater chance Brigitte Hüneke, Manuela Schmitz-Gerhardt and Barbara of getting high maximum levels than the less frequent Kläge for their perfect analyses of the IgG antibodies. analyzed other antibodies (Table 2). This also ap- Funding Open Access funding enabled and organized by plies to the maximum values of the literature. There Projekt DEAL. are more studies of IgG antibodies against the anti- gens pigeon [6–8, 12]and Aspergillus fumigatus [6, Declarations 13, 15–20] and thus higher chances for particularly high values than for other antigens as goose and duck Conﬂict of interest J. Sennekamp, E. Lehmann and M. Joest feathers [22, 34], isocyanates [21, 28, 29]or Saccha- declare that they have no competing interests. romyces cerevisiae [27]. For the maximum values and Ethical standards This is a retrospective study with anony- ranges of these rare antibodies further evaluations mized data. will be required in future. Concerning the frequencies, we would have liked Open Access This article is licensed under a Creative Com- mons Attribution 4.0 International License, which permits to evaluate more than the described eight antibod- use, sharing, adaptation, distribution and reproduction in ies of the HP screening test. However, an evaluation any medium or format, as long as you give appropriate credit attempt revealed extremely high frequencies of anti- to the original author(s) and the source, provide a link to bodies against birds and bed feathers. On the “visible” the Creative Commons licence, and indicate if changes were birds (meaning anamnestically recognizable), the hit made. The images or other third party material in this article rate is of course higher than on the “invisible” bacte- are included in the article’s Creative Commons licence, unless ria and molds. Therefore, such an evaluation would indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and distort the results. your intended use is not permitted by statutory regulation or An additional limitation of our study is the depen- exceeds the permitted use, you will need to obtain permis- dence of our results on the chosen cut-offs. The de- sion directly from the copyright holder. To view a copy of this cision to include only IgG values over the individual licence, visit http://creativecommons.org/licenses/by/4.0/. cut-offs of each antigen was taken because gradua- tion is only needed above the cut offs; below the cut offs all values are graded as negative. For some of K Improved IgG antibody diagnostics of hypersensitivity pneumonitis and pulmonary mycoses by means of. . . original article 19. Raulf M, Joest M, Sander I, Hoffmeyer F, Nowak D, References Ochmann U, et al. Update of reference values for IgG antibodies against typical antigens of hypersensitivity 1. Denning DW, Cadranel J, Beigelman-Aubry C, Ader F, pneumonitis. AllergoJInt. 2019;28:192–203. Chakrabarti A, Blot S, et al. Chronic pulmonary aspergillo- 20. Page ID, Richardson MD, Denning DW. Comparison of six sis; rationale and clinical guidelines for diagnosis and aspergillus speciﬁc IgG assays for the diagnosis of chronic management. EurRespirJ.2016;47:45–68. pulmonaryaspergillosis(CPA). JInfect. 2016;72:240–9. 2. Shirai T, Tanino Y, Nikaido T, Takaku Y, Hashimoto S, 21. Pronk A, Preller L, Raulf-Heimsoth M, et al. Respiratory Taguchi Y, et al. Screening and diagnosis of acute symptoms, sensitization, and exposure—response rela- and chronic bird-related hypersensitivity pneumonitis tionships in spray painters exposed to isocyanates. Am J by serum IgG and IgA antibodies to bird antigens with RespirCritCareMed. 2007;176:1090–7. ImmunoCAP. AllergolInt. 2021;70:208–14. 22. Koschel D, Lützkendorf L, Wiedemann B, Höffken G. Anti- 3. Page ID, Richardson M, Denning DW. Antibody testing in gen-speciﬁc IgG antibodies in feather duvet lung. Eur J Clin aspergillosis—quovadis? MedMycol. 2015;53:417–39. Invest. 2010;40:797–8032. 4. Richardson MD, Page ID. Aspergillus serology: have we 23. Sennekamp J. Extrinsicallergicalveolitis—hypersensitivity arrivedyet? MedMycol. 2017;55:48–55. pneumonitis. Munich,Orlando: Dustri-Verlag;2004. 5. Sennekamp J, Lehmann E, Joest M. Work related extrinsic 24. Costabel U, Miyazaki Y, Pardo A, Koschel D, Bonella F, allergicalveolitis. ASUInt. 2015;50:38–52. SpagnoloP,etal. Hypersensitivitypneumonitis. NatRevDis 6. Van Hoeyveld E, Dupont L, Bossuyt X. Quantiﬁcation of Primers. 2020;6:65. IgG antibodies to aspergillus fumigatus and pigeon anti- 25. Chowdhary A, Agarwal K, Kathuria S, Gaur SN, Rand- gens by ImmunoCAP technology: an alternative to the hawa HS, Meis JF. Allergic bronchopulmonary mycosis due precipitationtechnique? ClinChem. 2006;52:1785–93. to fungi other than aspergillus: a global overview. Crit Rev 7. McSharry C, Dye GM, Ismail T, Anderson K, Spiers EM, Microbiol. 2014;40:30–48. BoydG.Quantifyingserumantibodyinbirdfanciers’hyper- 26. SerranoC,TorregoA,LoosliA,ValeroA,PicadoC.Hypersen- sensitivitypneumonitis. BMCPulmMed. 2006;6:16. sitivity pneumonitis after exposure to Candida spp. Arch 8. Lopata AL, Schinkel M, Potter PC, Jeebhay MF, Hashemi C, Bronconeumol. 2010;46:275–7. Johansson SGO, et al. Qualitative and quantitative eval- 27. Gernhold M, Sennekamp J. Exogen-allergische Alveoli- uation of bird-speciﬁc IgG antibodies. Int Arch Allergy tis durch Backhefe (Saccharomyces cerevisiae). AL. Immunol. 2004;134:173–8. 2010;33:577–80. 9. Erkinjuntti-Pekkanen R, Reiman M, Kokkarinen JI, Tuki- 28. Baur X, Fischer A, Budnik LT. Spotlight on the diagnosis of ainen HO, Terho EO. IgG antibodies, chronic bronchitis, extrinsic allergic alveolitis (hypersensitivity pneumonitis). and pulmonary function values in farmer’s lung patients JOccupMedToxicol. 2015;10:15. andmatchedcontrols. Allergy. 1999;54:1181–7. 29. Schreiber J, Knolle J, Sennekamp J, Schulz KT, Hahn JU, 10. Lewis C, McSharry C, Anderson K, Speekenbrink A, Ke- Hering KG, et al. Subacute occupational hypersensitivity meny DM, Durnin S, et al. Quantifying serum antibody pneumonitis due low-level exposure to diisocyanates in class and subclass responses by enzyme immunoassay in asecretary. EurRespirJ.2008;32:807–11. humidiﬁer-relateddisease. ClinExpAllergy. 1991;21:601–7. 30. Liebetrau G, Bergmann KC. Morbiditäts- und Mortalität- 11. Woge MJ, Ryu JH, Moua T. Diagnostic implications of szahlen für die exogen-allergische Alveolitis (EAA). AL. positiveavian serology in suspectedhypersensitivity pneu- 1994;17:61–4. monitis. RespirMed. 2017;129:173–8. 31. Fernández Pérez ER, Swigris JJ, Forssén AV, Tourin O, 12. Khan S, Chowdhury SR, Ghosh S, Sengupta A, Ramasub- Solomon JJ, Huie TJ, et al. Identifying an inciting antigen is ban S, Sen D. Quantitation of avian IgG antibodies with associated with improved survival in patients with chronic clinico-radiological tests in the diagnosis of bird fancier’s hypersensitivitypneumonitis. Chest. 2013;144:1644–51. hypersensitivitypneumonitis. PulmoFace. 2015;15:48–54. 32. Joest M, Sennekamp J. Allergische bronchopulmonale 13. Fujiuchi S, Fujita H, Suzuki H, Doushita K, Kuroda H, Aspergillose (ABPA) und andere allergische bronchopul- Takahashi M, et al. Evaluation of a quantitative serological monale Mykosen (ABPM). Munich, Orlando: Dustri- assayfordiagnosingchronicpulmonaryaspergillosis. JClin Verlag;2020. Microbiol. 2016;54:1496–9. 33. Denning DW, Pleuvry A, Cole D. Global burden of allergic 14. YuQ,HeJ,XingB,LiX,QianH,ZhangH,etal. Potentialvalue bronchopulmonary aspergillosis with asthma and its com- of serum aspergillus IgG antibody detection in invasive plication chronic pulmonary aspergillosis in adults. Med and chronic pulmonary aspergillosis. BMC Pulm Med. Mycol. 2013;51:361–70. 2020;20:89. 34. Sennekamp J, Lehmann E. Optimierte IgG-Antikörper- 15. Agarwal R, Dua D, Choudhary H, Aggarwal AN, Sehgal IS, diagnostik der Bettfedern-Alveolitis mittels EAA-Suchtest. Dhooria S, et al. Role of Aspergillus fumigatus-speciﬁc IgG Pneumologie. 2015;69:638–44. in diagnosis and monitoring treatment response in allergic 35. Júnior MC, de Moraes Arantes A, Silva HM, Costa CR, bronchopulmonaryaspergillosis. Mycoses. 2017;60:33–9. Silva MRR, et al. Acremonium kiliense: case report 16. Kränke B, Woltsche M, Woltsche-Kahr I, Aberer W. IgG- and review of published studies. Mycopathologia. Antikörper gegen EAA-speziﬁsche Umweltantigene. AL. 2013;176:417–21. 2001;24:145–54. 36. EschenhagenP,GrehnC,SchwarzC.Prospectiveevaluation 17. Tan YH, Ngan CCL, Huang SW, Loo CM, Low SY. Speciﬁc of aspergillus fumigatus speciﬁc IgG in patients with cystic serum immunoglobulin G (IgG) levels against antigens im- ﬁbrosis. FrontCellInfectMicrobiol. 2021;10:602836. plicated in hypersensitivity pneumonitis in asymptomatic 37. Brouwer J. Cross-reactivity between aspergillus fumi- individuals. AnnAcadMedSingap. 2019;48:36–8. gatus and penicillium. Int Arch Allergy Immunol. 18. Makkonen K, Viitala KI, Parkkila S, Niemelä O. Serum 1996;110:166–73. IgG and IgE antibodies against mold-derivedantigens in 38. Vojdani A. Cross-reactivity of aspergillus, penicillium, and patiens with symptoms of hypersensitivity. Clin ChimActa. stachybotrys antigens using afﬁnity-puriﬁed antibodies 2001;305:89–98. andimmunoassay. ArchEnvironHealth. 2004;59:256–65. Improved IgG antibody diagnostics of hypersensitivity pneumonitis and pulmonary mycoses by means of. . . K original article 39. Richardson JP, Moyes DL. Adaptive immune responses to 43. Samson MH, Vestergaard JM, Knudsen CS, Kolstad HA. Candidaalbicansinfections. Virulence. 2015;6:327–37. Serum levels of IgG antibodies against aspergillus fumi- 40. HuertasB,PrietoD,PitarchA,GilC,PlaJ,Díez-OrejasR,etal. gatus and the risk of hypersensitivity pneumonitis and Serum antibody proﬁle during colonization of the mouse other interstitial lung diseases. Scand J Clin Lab Invest. gutbyCandidaalbicans. JProteomeRes. 2017;15:335–45. 2021;81:451–3. 41. Petnak T, Moua T. Exposure assessment in hypersensitiv- 44. Barton RC, Hobson RP, Denton M, Peckham D, Brownlee K, ity pneumonitis: a comprehensive review and proposed Conway S, et al. Serologic diagnosis of allergic bron- screeningquestionnaire. ERJOpenRes. 2020;6:230–2020. chopulmonary aspergillosis in patients with cystic ﬁbrosis 42. Quirce S, Vandenplas O, Campo P, Cruz MJ, de Blay F, through the detection of immunoglobulin G to aspergillus Koschel D, et al. Occupational hypersensitivity pneumoni- fumigatus. DiagnMicrobiolInfectDis. 2008;62:287–91. tis: anEAACIpositionpaper. Allergy. 2016;71:765–79. K Improved IgG antibody diagnostics of hypersensitivity pneumonitis and pulmonary mycoses by means of. . .

Journal

Allergo Journal International – Springer Journals

Published: May 17, 2022

Keywords: allergology; dermatology; environmental health; immunology

References

Chronic pulmonary aspergillosis

DW Denning, J Cadranel, C Beigelman-Aubry, F Ader, A Chakrabarti, S Blot
Screening and diagnosis of acute and chronic bird-related hypersensitivity pneumonitis by serum IgG and IgA antibodies to bird antigens with ImmunoCAP

T Shirai, Y Tanino, T Nikaido, Y Takaku, S Hashimoto, Y Taguchi
Antibody testing in aspergillosis—quo vadis?

ID Page, M Richardson, DW Denning
Aspergillus serology: have we arrived yet?

MD Richardson, ID Page
Work related extrinsic allergic alveolitis

J Sennekamp, E Lehmann, M Joest
Quantification of IgG antibodies to aspergillus fumigatus and pigeon antigens by ImmunoCAP® technology: an alternative to the precipitation technique?

E Van Hoeyveld, L Dupont, X Bossuyt
Quantifying serum antibody in bird fanciers’ hypersensitivity pneumonitis

C McSharry, GM Dye, T Ismail, K Anderson, EM Spiers, G Boyd
Qualitative and quantitative evaluation of bird-specific IgG antibodies

AL Lopata, M Schinkel, PC Potter, MF Jeebhay, C Hashemi, SGO Johansson
IgG antibodies, chronic bronchitis, and pulmonary function values in farmer’s lung patients and matched controls

R Erkinjuntti-Pekkanen, M Reiman, JI Kokkarinen, HO Tukiainen, EO Terho
Quantifying serum antibody class and subclass responses by enzyme immunoassay in humidifier-related disease

C Lewis, C McSharry, K Anderson, A Speekenbrink, DM Kemeny, S Durnin
Diagnostic implications of positive avian serology in suspected hypersensitivity pneumonitis

MJ Woge, JH Ryu, T Moua
Quantitation of avian IgG antibodies with clinico-radiological tests in the diagnosis of bird fancier’s hypersensitivity pneumonitis

S Khan, SR Chowdhury, S Ghosh, A Sengupta, S Ramasubban, D Sen
Evaluation of a quantitative serological assay for diagnosing chronic pulmonary aspergillosis

S Fujiuchi, H Fujita, H Suzuki, K Doushita, H Kuroda, M Takahashi
Potential value of serum aspergillus IgG antibody detection in invasive and chronic pulmonary aspergillosis

Q Yu, J He, B Xing, X Li, H Qian, H Zhang
Role of Aspergillus fumigatus-specific IgG in diagnosis and monitoring treatment response in allergic bronchopulmonary aspergillosis

R Agarwal, D Dua, H Choudhary, AN Aggarwal, IS Sehgal, S Dhooria
IgG-Antikörper gegen EAA-spezifische Umweltantigene

B Kränke, M Woltsche, I Woltsche-Kahr, W Aberer
Specific serum immunoglobulin G (IgG) levels against antigens implicated in hypersensitivity pneumonitis in asymptomatic individuals

YH Tan, CCL Ngan, SW Huang, CM Loo, SY Low
Serum IgG and IgE antibodies against mold-derivedantigens in patiens with symptoms of hypersensitivity

K Makkonen, KI Viitala, S Parkkila, O Niemelä
Update of reference values for IgG antibodies against typical antigens of hypersensitivity pneumonitis

M Raulf, M Joest, I Sander, F Hoffmeyer, D Nowak, U Ochmann
Comparison of six aspergillus specific IgG assays for the diagnosis of chronic pulmonary aspergillosis (CPA)

ID Page, MD Richardson, DW Denning
Respiratory symptoms, sensitization, and exposure—response relationships in spray painters exposed to isocyanates

A Pronk, L Preller, M Raulf-Heimsoth
Antigen-specific IgG antibodies in feather duvet lung

D Koschel, L Lützkendorf, B Wiedemann, G Höffken
Extrinsic allergic alveolitis—hypersensitivity pneumonitis

J Sennekamp
Hypersensitivity pneumonitis

U Costabel, Y Miyazaki, A Pardo, D Koschel, F Bonella, P Spagnolo
Allergic bronchopulmonary mycosis due to fungi other than aspergillus: a global overview

A Chowdhary, K Agarwal, S Kathuria, SN Gaur, HS Randhawa, JF Meis
Hypersensitivity pneumonitis after exposure to Candida spp

C Serrano, A Torrego, A Loosli, A Valero, C Picado
Exogen-allergische Alveolitis durch Backhefe (Saccharomyces cerevisiae)

M Gernhold, J Sennekamp
Spotlight on the diagnosis of extrinsic allergic alveolitis (hypersensitivity pneumonitis)

X Baur, A Fischer, LT Budnik
Subacute occupational hypersensitivity pneumonitis due low-level exposure to diisocyanates in a secretary

J Schreiber, J Knolle, J Sennekamp, KT Schulz, JU Hahn, KG Hering
Morbiditäts- und Mortalitätszahlen für die exogen-allergische Alveolitis (EAA)

G Liebetrau, KC Bergmann
Identifying an inciting antigen is associated with improved survival in patients with chronic hypersensitivity pneumonitis

ER Fernández Pérez, JJ Swigris, AV Forssén, O Tourin, JJ Solomon, TJ Huie
Allergische bronchopulmonale Aspergillose (ABPA) und andere allergische bronchopulmonale Mykosen (ABPM)

J Sennekamp
Global burden of allergic bronchopulmonary aspergillosis with asthma and its complication chronic pulmonary aspergillosis in adults

DW Denning, A Pleuvry, D Cole
Optimierte IgG-Antikörperdiagnostik der Bettfedern-Alveolitis mittels EAA-Suchtest

J Sennekamp, E Lehmann
Acremonium kiliense: case report and review of published studies

MC Júnior, A Moraes Arantes, HM Silva, CR Costa, MRR Silva
Prospective evaluation of aspergillus fumigatus specific IgG in patients with cystic fibrosis

P Eschenhagen, C Grehn, C Schwarz
Cross-reactivity between aspergillus fumigatus and penicillium

J Brouwer
Cross-reactivity of aspergillus, penicillium, and stachybotrys antigens using affinity-purified antibodies and immunoassay

A Vojdani
Adaptive immune responses to Candida albicans infections

JP Richardson, DL Moyes
Serum antibody profile during colonization of the mouse gut by Candida albicans

B Huertas, D Prieto, A Pitarch, C Gil, J Pla, R Díez-Orejas
Exposure assessment in hypersensitivity pneumonitis: a comprehensive review and proposed screening questionnaire

T Petnak, T Moua
Occupational hypersensitivity pneumonitis: an EAACI position paper

S Quirce, O Vandenplas, P Campo, MJ Cruz, F Blay, D Koschel
Serum levels of IgG antibodies against aspergillus fumigatus and the risk of hypersensitivity pneumonitis and other interstitial lung diseases

MH Samson, JM Vestergaard, CS Knudsen, HA Kolstad
Serologic diagnosis of allergic bronchopulmonary aspergillosis in patients with cystic fibrosis through the detection of immunoglobulin G to aspergillus fumigatus

RC Barton, RP Hobson, M Denton, D Peckham, K Brownlee, S Conway

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Improved IgG antibody diagnostics of hypersensitivity pneumonitis and pulmonary mycoses by means of newly evaluated serum antibody ranges and frequencies using IgG ImmunoCAP™

Improved IgG antibody diagnostics of hypersensitivity pneumonitis and pulmonary mycoses by means of newly evaluated serum antibody ranges and frequencies using IgG ImmunoCAP™

Get 20M+ Full-Text Papers For Less Than $1.50/day. Start a 14-Day Trial for You or Your Team.

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Improved IgG antibody diagnostics of hypersensitivity pneumonitis and pulmonary mycoses by means of newly evaluated serum antibody ranges and frequencies using IgG ImmunoCAP™

Improved IgG antibody diagnostics of hypersensitivity pneumonitis and pulmonary mycoses by means of newly evaluated serum antibody ranges and frequencies using IgG ImmunoCAP™

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