Department of Pediatrics, Kindai University Faculty of Medicine, 377-2 Ohno-higashi, Osaka-sayama, Osaka, 589-8511, Japan.
Department of Pediatrics, Kushimoto municipality Hospital, Wakayama, Japan.
BMC Nephrol. 2020 Feb 27;21(1):68. doi: 10.1186/s12882-020-01735-7.
IgA deficiency associated with glomerulonephritis is rare. In particular, there is no prior report regarding the association between IgA deficiency and membranoproliferative glomerulonephritis (MPGN) in children. Herein, we describe the case of a 5-year-old girl with selective IgA deficiency and MPGN.
The patient presented with persisting urinary abnormality and hypocomplementemia following a group A treptococcal infection. Renal biopsy revealed the presence of diffuse mesangial hypercellularity, endocapillary proliferation, and focal thickening of the walls of the glomerular capillaries using light microscopy, with IgG and moderate C3 deposits observed using immunofluorescence. Electron microscopy images revealed nodular deposits in the subendothelial areas, with hump-shaped subepithelial deposits. The pathological diagnosis was confirmed as MPGN. Treatment using oral prednisolone (PSL), mizoribine (MZR), and angiotensin-converting enzyme inhibitors reduced the proteinuria. The PSL dose was gradually tapered, with the low dose of PSL and MZR continued for 4 years. Histological findings were improved on repeated renal biopsy, and PSL and MZR administration was discontinued.
We report a rare case of MPGN related to a streptococcal infection in a child. The clinical presentation included selective IgAD, with several pathological findings and a clinical course typical of glomerulopathy. The patient was successfully treated using multidrug therapy.
IgA 缺乏症与肾小球肾炎相关的情况较为罕见。特别是，目前尚无儿童 IgA 缺乏症与膜增生性肾小球肾炎（MPGN）之间关联的报告。在此，我们报告一例 5 岁女孩存在选择性 IgA 缺乏症和 MPGN 的病例。
该患者因 A 组链球菌感染后持续出现尿液异常和低补体血症。肾脏活检显示，使用光镜观察到弥漫性系膜细胞增生、毛细血管内增殖和肾小球毛细血管壁局灶性增厚，免疫荧光显示 IgG 和中等 C3 沉积。电子显微镜图像显示在 subendothelial 区域存在结节状沉积物，有驼峰状的 subepithelial 沉积物。病理诊断为 MPGN。使用口服泼尼松龙（PSL）、吗替麦考酚酯（MZR）和血管紧张素转换酶抑制剂进行治疗后，蛋白尿减少。逐渐减少 PSL 剂量，继续使用低剂量 PSL 和 MZR 治疗 4 年。重复肾活检显示组织学发现改善，停止使用 PSL 和 MZR。
我们报告了一例儿童链球菌感染相关的罕见 MPGN 病例。临床表现包括选择性 IgAD，具有多种病理学发现和典型的肾小球病变的临床病程。该患者通过多药物治疗成功治疗。
