アミロイドーシスを合併したCrohn病の1例

Crohn's Disease Associated with Amyloidosis, Report of a Case

要旨　Crohn病発症後7～9年でアミロイドーシスを来した1例を報告する．患者は28歳，男性．1975年，腹痛・下痢で発症，1977年，Crohn病と診断され，狭窄のため某病院で右半結腸切除術および回腸部分切除術を施行された．1980年10月，再発のため当科を受診した．イレウス状態に陥り，1981年2月，残存結腸および回腸切除術を施行された．この時期の切除標本の検索では，腸管のアミロイド沈着は証明されなかった，その後の経過観察期間中，1983年8月の外来受診時までは，血清クレアチニンは正常だったが，1984年2月より上昇し，同年3月の再入院時には2.7mg/dlに達し，クレアチニン・クリアランスは20ml/minに低下，尿蛋白は1日約2gを認めた．アミロイドーシスの合併を考え検索したが，消化管の生検で胃と小腸・直腸よりアミロイド沈着を証明した．腎は生検を行っていないが，腎機能低下と尿蛋白陽性より腎アミロイドーシスと考えた．肝・心・甲状腺は，機能検査その他に異常は認められなかった．生検標本のアミロイド蛋白分析はtype AAで，二次性全身性アミロイドーシスと考えられた．

　We report a case of amyloidosis which developed 7 to 9 years after Crohn's disease had been diagnosed. The case was a 28 year-old male who had abdominal pain and diarrhea for the first time in 1975 (at the age of 19) . He was diagnosed as having Crohn's disease at another hospital in 1977, and right hemicolectomy and distal ileal resection were performed because of severe stenosis. In October, 1980 he was referred and admitted to the First Department of Fukuoka University under diagnosis of relapse of Crohn's disease. Intestinal obstruction developed during hospitalization, and the remnant colon and ileum were resected in February, 1981. Amyloid deposition was not found on pathological study of the resected specimen. Serum level of creatinine had been within normal range until 1983 ; however, its increase was first recognized in February, 1984. In March,1985 serum creatinine went up 2.7 mg/dl with creatinine clearance being 20 ml/min. Urinary excretion of protein was 2 gm per day.

　Secondary amyloidosis was suspected based on these findings. Amyloid deposition was recognized on histological study of biopsy specimens from the stomach, small intestine and rectum. Although renal biopsy was not done, renal involvement was also suspected because of renal dysfunction and proteinuria.

　Liver, heart and thyroid functions were unremarkable. Analysis of amyloid protein in the biopsy specimens showed type AA frequently seen in secondary amyloidosis. Crohn's disease associated with amyloidosis is rare, and this case seems to be the third one ever reported in Japan.