Hara Shigeo, Tsukaguchi Hiroyasu, Oka Tastufumi, Kusabe Makiko, Mizui Masayuki, Joh Kensuke
a Department of Diagnostic Pathology , Kobe University Graduate School of Medicine , Kobe , Japan.
b 2nd Department of Internal Medicine , Kansai Medical University , Hirakata , Japan.
Ultrastruct Pathol. 2017 Jul-Aug;41(4):301-307. doi: 10.1080/01913123.2017.1336189. Epub 2017 Jun 19.
We herein report the case of a 64-year-old male who presented with progressive glomerulonephritis notable for organized and striated ultra-substructures. The patient was diagnosed with hypertension and proteinuria 3 years prior to admission and subsequently developed nephrotic syndrome and impairment of renal function. Laboratory tests did not reveal any evidence of infections or autoimmune diseases. Monoclonal gammopathy was not detected in serum or urine, although a small population of abnormal plasma cell clones was detected by flow cytometry. A renal biopsy showed mesangial and endocapillary proliferative glomerulonephritis with lobular accentuation, accompanied with focal and segmental double-contour formation. Additionally, moderate tubulointerstitial scarring and arteriosclerosis were noted. Immunofluorescence staining revealed positive staining for IgG, IgM, C3, C1q, and fibrinogen. IgG subclass and light chain staining showed restricted positivity for IgG1κ. Electron microscopy demonstrated massive amounts of subendothelial deposits with a fibrillary and branching profile. At higher magnification, a periodic striated pattern was observed within the microfilament-like structures. Immunohistochemical staining was negative for myoglobin, laminin, and collagens (type III and IV). Steroid and antihypertensive therapy did not show improvement in renal function. The second biopsy performed 2 years later revealed a similar lobular proliferative glomerulonephritis pattern with more extensive tubulointerstitial damage, indicating poor response to immunosuppressive therapy. The patient progressed to end-stage renal disease and required hemodialysis. We discuss the possible origins of the deposits with unusual substructures observed in this case.
我们在此报告一例64岁男性患者，其表现为进展性肾小球肾炎，具有有组织的和条纹状的超微结构。患者在入院前3年被诊断为高血压和蛋白尿，随后发展为肾病综合征和肾功能损害。实验室检查未发现任何感染或自身免疫性疾病的证据。血清或尿液中未检测到单克隆丙种球蛋白病，尽管通过流式细胞术检测到一小群异常浆细胞克隆。肾活检显示系膜和内皮细胞增生性肾小球肾炎伴小叶突出，伴有局灶性和节段性双轨形成。此外，还注意到中度肾小管间质瘢痕形成和动脉硬化。免疫荧光染色显示IgG、IgM、C3、C1q和纤维蛋白原呈阳性染色。IgG亚类和轻链染色显示IgG1κ呈限制性阳性。电子显微镜显示大量内皮下沉积物，呈纤维状和分支状。在更高放大倍数下，在微丝样结构内观察到周期性条纹图案。免疫组织化学染色显示肌红蛋白、层粘连蛋白和胶原蛋白（III型和IV型）呈阴性。类固醇和抗高血压治疗未显示肾功能改善。2年后进行的第二次活检显示类似的小叶增生性肾小球肾炎模式，伴有更广泛的肾小管间质损伤，表明对免疫抑制治疗反应不佳。患者进展为终末期肾病，需要进行血液透析。我们讨论了在该病例中观察到的具有不寻常亚结构的沉积物的可能来源。
