ATG/FK506併用與移植後淋巴球增生疾病：一例報告

Combined Use of ATG/FK506 and Post-transplantation Lymphoproliferative Disorder: Report of A Case

移植後淋巴球增生疾病(Post-Transplantation Lymphoproliferative Disorder, PTLD)對器官移植者而言是嚴重且容易致死之併發症，其發生與Epstein-Barr病毒(EBV)的感染、免疫抑制劑的使用有重要的相關性。而隨著更新更強效之免疫抑制劑的問世，PTLD的發生率有逐漸增加的趨勢，尤其是anti-lymphocyte antibody(ALA)類之製劑。本病例報告為一接受腎臟移植患者，在以anti-thymocyte globulin(ATG)治療steroid-resistance rejection，並以FK506為後援藥物(rescue agent)持續治療約七個月後併發PTLD的個案。因ATG/FK506曾併用一週，且FK506五個月之平均血中濃度為11.3±2.5ng/ml，又移植前血清EBV-IgG呈陽性反應，移植後血清EBV-IgG titer升高，而懷疑其為免疫抑制劑相關之EBV再發性感染所引起之PTLD。由於過去文獻曾報導此二藥物之併用與過高的FK506血中濃度是導致PTLD發生的高危險因子，因此建議在非不得已使用此類藥物時應避免合併使用，且儘量維持FK506於較低的有效血中濃度範圍，並於事後作積極的追蹤監測，以早期發現、早期治療，提高移植器官及病患的存活率。

Posttransplant lymphoproliferative disorder (PTLD) is an important and life-threatening complication of transplantation. Epstein-Barr virus (EBV) infections and use of potent immunosuppressive agents are risk factors for the development of PTLD. The increase in the incidence of PTLD is accompanied by the development and availability of newer and potent immunosuppressors, such as anti-lymphocyte antibody (ALA) preparations. We report a case of renal transplantation with development of PTLD. Prior to development of the condition, the patient had received anti-thymocyte globulin (ATG) for the treatment of steroid-resistance rejection and used FK506 as a rescue agent for about seven months. ATG and FK506 were concurrently used for one week. The average serum concentration of FK506 was 11.3±2.5 ng/ml. The combined use of two potent immunosuppressors and excess blood level of FK506 are risk factors for PTLD.