Crohn病類似の腸病変を呈した慢性活動性Epstein-Barr virus感染症の1例

Chronic Active Epstein-Barr Virus Infection Mimicking Crohn's Disease, Report of a Case

要旨　患者は34歳の男性．当初回腸末端の不整形潰瘍，結腸の類円形潰瘍，縦走潰瘍からCrohn病を疑われた．steroid使用にて一時症状は軽快するが狭窄を呈し手術が施行された．その後も約1年にわたり発熱，腹痛が持続．播種性血管内凝固症候群で緊急入院した際，異常な抗Epstein-Barr virus（EBV）抗体価と血中EBVの増加から慢性活動性EBV感染症（chronic active EBV infection ; CAEBV）と診断した．CAEBVは数か月以上伝染性単核球症様の症状が持続し，5年で約半数が致死的となる疾患である．本症例はCrohn病類似の腸病変を呈したこと，steroidで一時症状が軽減したことで診断に難渋した．Crohn病と診断された症例でも不明熱が持続する場合はCAEBVの消化管病変の可能性も考え，EBVの検索をすることが必要であると考えられた．

　We recently encountered a 34-year-old man who presented with skipping ulcers in the small and large intestines and who underwent surgery for stenosis of the descending colon. The patient was diagnosed with Crohn's disease. Interstitial pneumonia subsequently developed, accompanied by fever, lymphadenopathy and disseminated intravascular coagulation and consequently chronic active Epstein-Barr virus infection (CAEBV) was diagnosed. Initial colonoscopy and surgical specimens showed marked invasion of Epstein-Barr virus infected lymphocytes around the ulcers, indicating that CAEBV-associated intestinal lesions had in fact been present in this patient from the start of his symptoms. In this case, diagnosis of CAEBV infection was delayed because both this infection and Crohn's disease respond to steroid therapy and because the patient displayed intestinal lesions resembling Crohn's disease. Some patients diagnosed with Crohn's disease (accompanied by fever) who died without responding to treatment were probably actually suffering form CAEBV infection.