Nephrology Department, Erasme Hospital, Université Libre de Bruxelles, Brussels, Belgium ; Experimental Nephrology Unit, Faculty of Medicine, Université Libre de Bruxelles, Brussels, Belgium.
Department of Pathology, Tenon Hospital, Paris, France.
Clin Kidney J. 2012 Jun;5(3):225-8. doi: 10.1093/ckj/sfs048. Epub 2012 May 3.
A 65-year-old man presented with a progressive increase in plasma creatinine (PCr). Two years before, diffusion-weighted magnetic resonance imaging had revealed a relapse of immunoglobulin G4 (IgG4)-related autoimmune pancreatitis (AIP) associated with sclerosing cholangitis. Bilateral hypointense renal cortical nodules were also described. Kidney biopsy showed patchy disappearance of tubules, sparse interstitial fibrosis and IgG4+ plasma cells (>30 per high power field) leading to the diagnosis of IgG4-related tubulointerstitial nephritis (TIN). Despite methylprednisolone, PCr and serum IgG4 levels remained elevated. Starting azathioprine (AZA) normalized IgG4 levels, which elicited corticosteroid withdrawal after 17 months. One year later, renal function remains stable. Our clinical observation underlines the importance of biological and radiological long-term follow-up of patients with previous AIP in order to early detect IgG4-related renal involvement. Corticosteroids are the first choice, but in the case of adverse effects or partial remission, AZA could be a useful and safe alternative therapy.
一位 65 岁男性因血浆肌酐（PCr）逐渐升高就诊。两年前，弥散加权磁共振成像显示免疫球蛋白 G4（IgG4）相关自身免疫性胰腺炎（AIP）伴硬化性胆管炎复发。还描述了双侧低信号肾皮质结节。肾脏活检显示肾小管局灶性消失，间质纤维化稀疏，IgG4+浆细胞（>30 个/高倍视野），诊断为 IgG4 相关肾小管间质性肾炎（TIN）。尽管使用了甲基强的松龙，PCr 和血清 IgG4 水平仍居高不下。开始使用硫唑嘌呤（AZA）使 IgG4 水平正常化，在 17 个月后停用皮质类固醇。一年后，肾功能仍保持稳定。我们的临床观察强调了对既往有 AIP 的患者进行生物和影像学长期随访的重要性，以便及早发现 IgG4 相关的肾脏受累。皮质类固醇是首选，但在出现不良反应或部分缓解的情况下，AZA 可能是一种有用且安全的替代治疗方法。
