Matsumura Daisuke, Tanaka Atsushi, Nakamura Tsukasa, Sato Eiichi, Node Koichi
Division of Nephrology, Department of Internal Medicine, Shinmatsudo Central General Hospital, Matsudo, and.
Deaprtment of Cardiovascular Medicine, Saga University, Saga, Japan.
Clin Nephrol Case Stud. 2016 Dec 12;4:24-28. doi: 10.5414/CNCS108889. eCollection 2016.
Rapid progression to end-stage renal disease has been reported in a minority of patients with immunoglobulin A (IgA) nephropathy. In particular, crescentic IgA nephropathy has a poor prognosis in patients with a higher initial serum creatinine level. The complement system plays an important role in the pathogenesis of crescentic IgA nephropathy. Atypical hemolytic uremic syndrome (aHUS), which is characterized by thrombotic microangiopathy, is distinct from Shigatoxin-induced HUS and thrombotic thrombocytopenic purpura. aHUS is associated with dysregulation of the alternative complement system. Eculizumab, an anti-C5 antibody, is effective in limiting complement activation in patients with paroxysmal nocturnal hemoglobinuria, aHUS, or refractory IgA nephropathy in some case reports. We herein report the case of a 42-year-old man with acute kidney injury (AKI) clinically and histologically diagnosed with the coexistence of aHUS and crescentic IgA nephropathy. The patient was treated with steroids, plasmapheresis, and hemodialysis; however, eculizumab treatment was initiated on hospital day 21 due to resistance to and dependence on the conventional aggressive therapy. Clinical remission of aHUS was achieved on day 70, but the renal function failed to recover from dialysis dependence. To the best of our knowledge, this is the first report showing the clinical course of a refractory patient with the coexistence of aHUS and crescentic IgA nephropathy treated with eculizumab. This case highlights the clinical importance of early diagnosis and appropriate initiation of eculizumab for the treatment of this type of AKI.
少数免疫球蛋白A（IgA）肾病患者已被报道会迅速进展至终末期肾病。特别是，新月体性IgA肾病在初始血清肌酐水平较高的患者中预后较差。补体系统在新月体性IgA肾病的发病机制中起重要作用。非典型溶血尿毒综合征（aHUS）以血栓性微血管病为特征，与志贺毒素诱导的溶血尿毒综合征和血栓性血小板减少性紫癜不同。aHUS与替代补体系统的失调有关。在一些病例报告中，抗C5抗体依库珠单抗在限制阵发性夜间血红蛋白尿、aHUS或难治性IgA肾病患者的补体激活方面有效。我们在此报告一例42岁男性急性肾损伤（AKI）患者，临床和组织学诊断为aHUS与新月体性IgA肾病并存。患者接受了类固醇、血浆置换和血液透析治疗；然而，由于对传统积极治疗耐药且依赖，在住院第21天开始使用依库珠单抗治疗。aHUS在第70天实现临床缓解，但肾功能未能从透析依赖中恢复。据我们所知，这是首例报告用依库珠单抗治疗aHUS与新月体性IgA肾病并存的难治性患者的临床过程。该病例突出了早期诊断和适当启动依库珠单抗治疗此类AKI的临床重要性。
