IgA肾病简明半定量病理评分方法及其与预后的关系

目的 建立一个用于预测预后且相对简明的IgA肾病组织学半定量评分方法。方法回顾性分析北京大学第一医院肾内科确诊为原发性IgA肾病并有2年以上随访资料的患者155例,终点事件为进入不可逆的终末期肾衰竭（ESRD）。所有病理切片均经重新阅片,其中91例由一位病理医师分别两次阅片,56例由两位病理医师分别独立阅片评分,判断重复性。初始的8个病理指标指数：（1）内皮细胞增生（endoI）;（2）活动性新月体及节段性袢坏死（dGAI）;（3）系膜细胞增生（MsHI）;（4）系膜基质增多（MsMI）;（5）肾小球慢性病变（GCI）;（6）肾间质炎症细胞浸润（infl）;（7）肾小管萎缩和肾间质纤维化（TCI）;（8）小动脉慢性病变（VCI）。结果 肾穿时Scr为（112．18±83．13）μmol/L。25例患者（16．13%）在随访期内[（69．07±28．66）月,10～170个月]达到终点（ESRD）。对初始的8个病理指标进行多变量生存分析,选出以下3个与预后最相关的变量组成评分方法：dGAI、GCI和TCI。后两项之和组成慢性指数CI。在多因素生存分析中,dGAI和CI都与肾脏生存率呈正相关（RR分别为1．255和1．691,P＜0．05）,是影响预后的独立危险因素。根据患者的dGAI和CI进行分组．显示dGAI≥4且CI≥6者预后最差（P＜0．01）。对CKDⅠ、Ⅱ期患者的多种临床病理指标进行多因素生存分析,仅CI是影响预后的独立危险因素。评分法具有良好的重复性,kappa值均大于0．4。结论 由代表活动性病变的dGAI和代表慢性病变的CI组成的IgA肾病组织学半定量评分法能够有效地判断预后,且具有良好的重复性。

A concise semi-quantitative pathological scoring method for IgA nephropathy and it''''s relation to renal outcome

Objective To establish a relatively concise semi-quantitative pathological scoring and approach to predict the prognosis of IgA nephropathy (IgAN). Methods One hundred and fifty-five cases diagnosed as primary IgA nephropathy with 2 years follow-up were enrolled into our study. In order to examine intra- and inter-observer reproducibility of classification according to the scores, pathological data of 91 cases were reviewed twice by one pathologist, and data of 56 cases were reviewed again by another pathologist. Eight histological indices were analyzed at the beginning: (1) endothelial proliferative index (endoI). (2) active crescents and segmental necrosis of glomerular capillary wall (dGAI). (3) mesangial hypercellularity index (MsHI). (4) increment of mesangial matrix area (MsMI). (5) glomerular chronicity index (GCI). (6) interstitial inflammatory cells infiltration (infI). (7) tubular atrophy and interstitial fibrosis (TCI). (8) vascular chronicity index (VCI). Results Twenty-five (16.13%) patients progressed into irreversible end stage renal disease (ESRD) during follow-up period [(69.07±28.66) months, ranged from 10 to 170 months]. Serum creatinine at biopsy was（112.18±83.13） μmol/L. The initial histological variables were analyzed using Cox proportional hazard model and three variables, including dGAI，GCI and TCI, were finally chosen. GCI and TCI were added up to indicate the chronicity index (CI). dGAI and CI were both found as independent factors in predicting renal outcome (RR=1.255 and 1.691, P<0.05, respectively). Patients in group with both higher dGAI (≥4) and CI (≥6) had the worst renal prognosis (P<0.01). For patients in CKD grade 1 and grade 2, multivariate analysis including clinical and histological variables showed CI was the only independent risk factor of bad prognosis. The reproducibility of the scoring system was proved acceptable (inter- and intra-observer’s kappa values >0.4). Conclusions This relatively concise pathological scoring method containing dGAI and CI has good reproducibility and can predict renal outcome of IgAN.