作者报道1例肝移植术后用 FK506治疗引起恶性单克隆淋巴瘤。患儿,男,6岁。因患有先天性胆道闭锁,于2个月龄时做手术,3个月龄时恢复。1990年由于肝功能进行性减退(血清总胆红素1 005μzmol/L),于1990年9月行部分肝移植。最初用免疫抑制剂环孢霉素、硫唑瞟呤、强的松,由于急性排斥反应,在术后第50天于类固醇冲击治疗后,改成 FK506与强的松联用。血浆 FK506谷值浓度通过与酶有关的免疫吸附剂检测,维持在0.4～1.0ng/ml。12月末,腹泻后便潜血阳性,乙状结肠镜检查发现,在乙状结肠和直肠粘膜下有几个肿物,其中二个大的肿物中央坏死。组织学显示弥漫性大细胞恶性淋巴瘤,具有单克隆 B 细胞卡巴粒增殖的特征。活检标本通过聚合酶链反应,发现 EB 病毒(EBV)。病人术前 EBV 血清学阳性, The authors reported 1 case of malignant monoclonal lymphoma treated with FK506 after liver transplantation. Children, male, 6 years old. Because of congenital biliary atresia, surgery at 2 months of age, 3 months of age recovery. In 1990 due to the progressive decline of liver function (serum total bilirubin 1005μzmol / L), in September 1990 underwent partial liver transplantation. Initially with the immunosuppressive agents cyclosporine, azathioprine, prednisone, due to acute rejection, 50 days after the steroid impact treatment, changed to FK506 and prednisone combined. The plasma FK506 trough concentration was maintained at 0.4-1.0 ng / ml as measured by the enzyme-linked immunosorbent. At the end of December, after the diarrhea was occult blood positive, sigmoidoscopy found in the sigmoid colon and rectal mucosa there are several tumors, of which two large tumor central necrosis. Histologically, diffuse large cell malignant lymphoma has been shown to have the characteristic of proliferation of the monoclonal B-cell card. Biopsy specimens were detected by polymerase chain reaction and found to be Epstein-Barr virus (EBV). Patients preoperative EBV serology positive,