背景:免疫球蛋白G4相关疾病是一种影响包括肾脏在内的多个器官的炎性疾病。免疫球蛋白G4相关的肾脏疾病最常表现为肾小管间质性肾炎,并在一定比例的病例中与肾小球疾病有关。膜性肾病是最常见的肾小球病变。在这里,我们报告了首例有记录的免疫球蛋白G4相关疾病病例,其表现为因微小病变导致的肾病综合征.
方法:一名67岁的南亚男性因全身不适和腿部肿胀出现在我们的服务中。他有大量蛋白尿(尿蛋白:肌酐比率1042mg/mmol),低白蛋白血症(17g/L)和高胆固醇血症(9.3mmol/L),与肾病综合征一致.血清肌酐为140μmol/L,并且他的补体不足(C30.59g/L,C4<0.02g/L),免疫球蛋白G4亚类水平升高(5.29g/L)。肾脏活检显示微小病变,同时伴有富含浆细胞的肾小管间质性肾炎,免疫球蛋白G4染色呈阳性。在免疫球蛋白G4相关疾病的背景下诊断为微小变化疾病。他开始口服泼尼松龙,每天60mg,但有感染并发症,包括开始治疗3周内的坏死性筋膜炎,最终导致他在初次陈述后52天死亡。
结论:该病例强调了免疫球蛋白G4相关疾病与一系列肾小球病变(包括微小病变)相关的可能性。它增加了微小变化疾病的次要原因的鉴别诊断,而且,艾滋病作为其治疗中使用大剂量类固醇的潜在并发症的重要提醒。
BACKGROUND: Immunoglobulin G4-related disease is an inflammatory disease affecting multiple organs including the kidney. Immunoglobulin G4-related kidney disease most commonly manifests as a tubulointerstitial nephritis and is associated with glomerular disease in a proportion of cases. Membranous nephropathy is the most frequent glomerular lesion. Herein, we report the first documented case of immunoglobulin G4-related disease presenting with nephrotic syndrome owing to minimal change disease.
METHODS: A 67-year-old South Asian male presented to our service with systemic upset and leg swelling. He had heavy proteinuria (urine protein:creatinine ratio 1042 mg/mmol) and was hypoalbuminemic (17 g/L) and hypercholersterolemic (9.3 mmol/L), consistent with the nephrotic syndrome. His serum creatinine was 140 μmol/L, and he was hypocomplementemic (C3 0.59 g/L, C4 < 0.02 g/L) with raised immunoglobulin G4 subclass levels (5.29 g/L). Kidney biopsy demonstrated minimal change disease alongside a plasma-cell-rich tubulointerstitial nephritis with strong positive staining for immunoglobulin G4. A diagnosis of minimal change disease in the setting of immunoglobulin G4-related disease was made. He was commenced on oral prednisolone at 60 mg daily but suffered infectious complications, including necrotizing fasciitis within 3 weeks of starting treatment, ultimately resulting in his death 52 days after initial presentation.
CONCLUSIONS: This case highlights the potential for immunoglobulin G4-related disease to be associated with a spectrum of glomerular pathologies including minimal change disease. It adds to the differential diagnosis of secondary causes of minimal change disease, and moreover, aids as an important reminder of the potential complications of high-dose steroids used in its treatment.