Wen Y K, Chen M L
Division of Nephrology, Department of Internal Medicine, Changhua, Taiwan.
Clin Nephrol. 2010 Mar;73(3):173-9. doi: 10.5414/cnp73173.
The characteristics of post infectious glomerulonephritis (PIGN) now differ from what were described decades ago. After encountering several patients of PIGN with atypical morphology, we conducted this retrospective study to determine the significance in the changes of clinicopathological spectrum of the disease.
Between July 2000 and February 2009, 21 cases of PIGN were identified at a medical center in Taiwan. The patients' records were reviewed with respect to clinical presentation, microbiology, serology, morphology of renal biopsy, and clinical course.
The mean age was 60.4 years. All patients developed acute renal failure and the majority (66.7%) required dialysis support. Hypocomplementemia was present in 61.9% of patients. The most frequently identified infectious agent was Staphylococcus (57.1%). Histological characteristics showed two distinct patterns of PIGN. One was diffuse endocapillary proliferation typical of PIGN (61.9%) and the other was atypical pattern of focal mesangial proliferation (38.1%). In comparison, glomerular neutrophil infiltration was more commonly present in typical pattern (p = 0.018). Glomerular IgA dominant or co-dominant deposition was more frequently seen in atypical pattern (p = 0.032). However, there were no statistically significant differences in the clinical presentation and outcome between the two groups. Our data also showed that the percentage of patients with atypical morphology PIGN significantly increased over time.
Atypical pattern of focal mesangial proliferative glomerulonephritis may represent a resolution stage of PIGN. The nature of subclinical infection with a more protracted course may contribute to the increasing recognition of this resolving PIGN at the time of renal biopsy. Another possible explanation is that the atypical morphology may be a peculiar pattern of poststaphylococcal glomerulonephritis which was increasingly identified in PIGN over the past 10 years.
感染后肾小球肾炎（PIGN）的特征如今已与数十年前所描述的不同。在遇到几例具有非典型形态的PIGN患者后，我们开展了这项回顾性研究，以确定该疾病临床病理谱变化的意义。
2000年7月至2009年2月期间，台湾某医疗中心确诊了21例PIGN患者。回顾了患者关于临床表现、微生物学、血清学、肾活检形态以及临床病程的记录。
平均年龄为60.4岁。所有患者均发生急性肾衰竭，大多数（66.7%）需要透析支持。61.9%的患者存在低补体血症。最常鉴定出的感染病原体是葡萄球菌（57.1%）。组织学特征显示PIGN有两种不同模式。一种是PIGN典型的弥漫性毛细血管内增生（61.9%），另一种是非典型的局灶性系膜增生模式（38.1%）。相比之下，典型模式中肾小球中性粒细胞浸润更为常见（p = 0.018）。非典型模式中更常出现肾小球IgA为主或共同为主的沉积（p = 0.032）。然而，两组之间的临床表现和结局并无统计学显著差异。我们的数据还显示，具有非典型形态PIGN的患者百分比随时间显著增加。
局灶性系膜增生性肾小球肾炎的非典型模式可能代表PIGN的一个消退阶段。亚临床感染病程较长的性质可能导致在肾活检时对这种消退性PIGN的认识增加。另一种可能的解释是，非典型形态可能是葡萄球菌感染后肾小球肾炎的一种特殊模式，在过去10年中在PIGN中越来越多地被发现。
