INTRODUCTION Hypersensitivity pneumonitis (HP) is the third most common interstitial lung disease, and is often under-recognized, especially in patients who are not aware of their occupational or environmental contact with organic antigens. The aim of the present study was to assess the results of serum specific IgG antibodies (ssIgG) in HP patients and their correlation with clinical data. MATERIAL AND METHODS 128 HP patients, median age 53 years, participated in the study. The control group consisted of 102 patients with interstitial lung diseases (ILDs) other than HP. Assessment of pretreatment ssIgG to thermophilic actinomycetes and protein antigens from bird droppings (pigeons, hens, ducks, parrots, turkeys) was performed by double diffusion in agar gel according to Ouchterlony method. RESULTS Positive precipitins were obtained in 57% of all HP patients and in 61% of those exposed to above mentioned antigens. Positive results in the control group were obtained in 7% of patients. Sensitivity of ssIgG in HP group was 0.57 and specificity 0.93. Precipitins to at least one bird antigen was confirmed in 64% of HP patients exposed to birds. Precipitins to thermophilic bacteria were found in 29% of HP patients exposed to hay or hay products. CONCLUSIONS The results of the study indicate that ssIgG against birds' allergens were the valuable diagnostic tool in HP patients. Low-rate of confirmation of ssIgG to thermophilic bacteria in patients exposed to hay or hay products indicate that other microorganisms, most likely molds, could be responsible for the disease development.

中文翻译：

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血清沉淀素对诊断为过敏性肺炎患者的特定抗原的价值 - 回顾性研究。

引言 过敏性肺炎 (HP) 是第三大最常见的间质性肺病，并且通常未被充分认识，尤其是在不知道其职业或环境接触有机抗原的患者中。本研究的目的是评估 HP 患者血清特异性 IgG 抗体 (ssIgG) 的结果及其与临床数据的相关性。材料和方法 128 名 HP 患者，中位年龄 53 岁，参加了研究。对照组由 102 名除 HP 以外的间质性肺病 (ILD) 患者组成。根据 Ouchterlony 方法，通过在琼脂凝胶中的双重扩散对来自鸟粪（鸽子、母鸡、鸭子、鹦鹉、火鸡）的嗜热放线菌和蛋白质抗原的预处理 ssIgG 进行评估。结果 57% 的 HP 患者和 61% 的暴露于上述抗原的患者获得了阳性沉淀素。对照组有 7% 的患者获得阳性结果。HP组ssIgG的敏感性为0.57，特异性为0.93。64% 接触鸟类的 HP 患者证实了至少一种鸟类抗原的沉淀素。在 29% 的接触干草或干草产品的 HP 患者中发现了嗜热细菌的沉淀素。结论 研究结果表明，针对鸟类过敏原的 ssIgG 是 HP 患者有价值的诊断工具。暴露于干草或干草产品的患者中嗜热细菌的 ssIgG 确认率较低，这表明其他微生物，最有可能是霉菌，可能是导致疾病发展的原因。