診断に難渋した副鼻腔炎を伴うANCA関連血管炎の1例

A case of ANCA-associated vasculitis with sinusitis difficult to diagnose

はじめに

　抗好中球細胞質抗体（anti-neutrophil cytoplasmic antibody：ANCA）関連血管炎（ANCA-associated vasculitis：AAV）は，その上気道病変に耳鼻咽喉科領域である中耳・鼻副鼻腔・喉頭などを含む。しかし，その血管炎は主として全身の小血管に起こり多彩な症状を呈するため，耳鼻咽喉科医単独ではしばしば診断に苦慮することが多く，その結果治療開始が遅れた報告も認める^1,2）。

　本報告では，抗菌薬に反応しない頭痛を伴う副鼻腔炎の治療に苦慮したが，その後肺病変，急速な腎機能障害，およびMPO（myeloperoxidase）-ANCA高値が明らかとなり，AAVのうち多発血管炎性肉芽腫症（granulomatosis with polyangiitis：GPA）の診断に至った1例を経験したので，若干の考察を加えて報告する。

　A 62-year-old man, unresponsive to antibiotic treatment, presented with symptoms of sinusitis including headache, fever, and high WBC/CRP levels. Due to the development of lung lesions, rapidly progressing renal deterioration, and high myeloperoxydase-anti-neutrophil cytoplasmic antibody（MPO-ANCA）levels, this case met the criteria for granulomatosis with polyangiitis（GPA）in ANCA-associated vasculitis（AAV）. After glucocorticoids and rituximab were administered and HD was performed, remission was induced, and the patient was discharged.

　AAV, a systemic small-vessel disease, may present with some ENT areas unresponsive to antibiotics. It becomes the otolaryngologist's responsibility to link it to treatment as soon as possible in cooperation with other departments, keeping AAV in mind.