Tanaka Y, Satoh F, Komatsu T, Muto H, Akiyama N, Arai Y, Miyamoto Y, Sano Y
Department of Allergy and Respiratory Disease, Doai Memorial Hospital, Tokyo, Japan.
Nihon Kyobu Shikkan Gakkai Zasshi. 1994 Jun;32(6):606-9.
A 38-year-old male presented complaining of an asthma attack. He had a past history of allergic rhinitis and conjunctivitis, family history of bronchial asthma and atopic dermatitis. He was an orthopedist who had been using cast materials containing methylene diphenyl isocyanate (MDI) for one year, and had developed an early asthmatic response while handling the casts. An acetylcholine inhalation test was done and his value was 20000 micrograms/ml. The scratch test for the cast materials was negative though the inhalation challenge test was positive. We suspected that the patient was suffering from bronchial asthma induced by MDI contained in the cast materials. Studies using isocyanates conjugated with human serum albumin were performed. The results were as follows: IgE-RAST negative, ELISA demonstrated the existence of specific IgG for both toluene diisocyanate (TDI) and MDI, as well as IgG4 for both TDI and MDI. The cast contained MDI but not TDI. We therefore considered TDI to be cross-reactant. It was likely that chronic exposure enhancing specific IgG4 and specific IgG might have caused the high IgG4 value. This is the first case of occupational asthma in an orthopedist due to isocyanates.
一名38岁男性因哮喘发作前来就诊。他有过敏性鼻炎和结膜炎病史，家族中有支气管哮喘和特应性皮炎病史。他是一名骨科医生，使用含二苯基甲烷二异氰酸酯（MDI）的石膏材料已有一年，在处理石膏时出现了早期哮喘反应。进行了乙酰胆碱吸入试验，其值为20000微克/毫升。石膏材料的划痕试验为阴性，但吸入激发试验为阳性。我们怀疑该患者患有由石膏材料中所含MDI引起的支气管哮喘。进行了使用与人类血清白蛋白结合的异氰酸酯的研究。结果如下：IgE-RAST阴性，ELISA显示存在针对甲苯二异氰酸酯（TDI）和MDI的特异性IgG，以及针对TDI和MDI的IgG4。石膏中含有MDI但不含TDI。因此我们认为TDI是交叉反应物。慢性暴露增强特异性IgG4和特异性IgG可能导致了高IgG4值。这是首例因异氰酸酯导致骨科医生患职业性哮喘的病例。
