腎移植後5年目の患者に発症したミコフェノール酸モフェチル関連多発回腸潰瘍の1例

Mycophenolate Mofetil-related Multiple Ileal Ulcer in a Patient 5 Years after Kidney Transplantation, Report of a Case

要旨●患者は50歳代前半，女性．40歳代後半に人工透析を要する慢性腎不全のため生体腎移植を受けた．移植後はミコフェノール酸モフェチル（MMF），タクロリムス，メチルプレドニゾロンで免疫抑制療法が継続された．移植後5年を経過したころより，20行/day以上の水様下痢が出現した．血便は認めなかった．症状は6か月継続し，その間12kgの体重減少を認めた．下部消化管内視鏡検査で終末回腸に多発する潰瘍性病変を認め，生検病理組織像では炎症性腸疾患様の形質細胞やリンパ球の浸潤を認め，アポトーシス小体も認めた．感染症，リンパ増殖性疾患，炎症性腸疾患の併発は否定的であり，MMF関連回腸潰瘍と診断した．MMFの減量により下痢症状は改善し，内視鏡検査で回腸潰瘍の瘢痕化を確認した．

　The case was a woman in her early 50s who had received a living kidney transplant in her late 40s due to chronic renal failure that required dialysis. Immunosuppressive therapy was continued after the transplant with MMF（mycophenolate mofetil）, tacrolimus, and methylprednisolone. Five years after the transplant, the patient began experiencing watery diarrhea without bloody stools more than 20 times a day. These symptoms lasted for six months, and the patient lost 12kg of body weight during this time. An endoscopic examination of the lower gastrointestinal tract revealed multiple ulcerative lesions in the terminal ileum, and a biopsy of the pathological tissue showed infiltration of inflammatory bowel disease-like plasma cells and lymphocytes, and apoptotic bodies. An infection, lymphoproliferative disease, and complications from inflammatory bowel disease were ruled out, and the patient was diagnosed with a MMF-related ileal ulcer. The diarrhea improved with the reduction of MMF, and an endoscopic examination confirmed that the ileal ulcers had healed.