Department of Pediatric Nephrology, School of Medicine, Tokyo Women's Medical University, 8-1, Kawada-cho, Shinjuku-ku, Tokyo, 162-8666, Japan.
Department of Pediatrics, Teikyo University, 2-11-1, Kaga, Itabashi-ku, Tokyo, Japan.
CEN Case Rep. 2020 Nov;9(4):423-430. doi: 10.1007/s13730-020-00501-w. Epub 2020 Jul 3.
Parvovirus B19 (PVB19) has been known to cause acute glomerulonephritis and nephrotic syndrome with various renal histologic patterns, such as endocapillary glomerulonephritis and collapsing glomerulopathy. Remission is achieved spontaneously or by treatment with steroid and/or immunosuppressants in most patients, except those with sickle cell anemia or two APOL1 risk alleles. In this study, we report the case of a previously healthy 5-year-old boy with infection-related glomerulonephritis (IRGN) associated with PVB19 that progressed to end-stage renal disease (ESRD). He presented with macrohematuria, nephrotic-range proteinuria, and progressive renal dysfunction despite treatment with methylprednisolone pulse therapy, plasmapheresis, and intravenous immunoglobulin. The kidney biopsy specimens exhibited endocapillary infiltration and mesangiolysis with cellular crescent formation. Immunofluorescence analysis revealed that IgA was dominantly positive in the glomeruli, with some co-localized with KM55, which is a specific monoclonal antibody for galactose-deficient IgA1 (Gd-IgA1). The intensity of the KM55 signal in the present patient was weaker than that in patients with IgA nephropathy. To our knowledge, this is the first report of IRGN associated with PVB19 that progressed to ESRD without any underlying diseases. Further investigations are needed to determine the significance of IgA and Gd-IgA1 deposition in IRGN associated with PVB19.
微小病毒 B19（PVB19）已知可引起急性肾小球肾炎和肾病综合征，具有多种肾组织学模式，如内皮下肾小球肾炎和塌陷性肾小球病。大多数患者在自发或接受类固醇和/或免疫抑制剂治疗后可缓解，除了镰状细胞贫血或两个 APOL1 风险等位基因的患者。在本研究中，我们报告了一例先前健康的 5 岁男孩，他患有与 PVB19 相关的感染性肾小球肾炎（IRGN），进展为终末期肾病（ESRD）。尽管接受了甲基强的松龙脉冲治疗、血浆置换和静脉注射免疫球蛋白治疗，他仍出现了大量血尿、肾病范围蛋白尿和进行性肾功能不全。肾脏活检标本显示内皮下浸润和系膜溶解，伴有细胞性新月体形成。免疫荧光分析显示 IgA 在肾小球中呈优势阳性，有些与 KM55 共定位，KM55 是一种针对半乳糖缺乏 IgA1（Gd-IgA1）的特异性单克隆抗体。与 IgA 肾病患者相比，本患者的 KM55 信号强度较弱。据我们所知，这是首例无潜在疾病的与 PVB19 相关的 IRGN 进展为 ESRD 的病例报告。需要进一步研究以确定 IgA 和 Gd-IgA1 在与 PVB19 相关的 IRGN 中的沉积意义。
