少量蛋白尿和（或）血尿IgA肾病临床病理分析

Clinicopathological analysis of IgA nephropathy patients with mild proteinuria and/or hematuria Saruultuvshin

目的 了解表现为少量蛋白尿和（或）血尿IgA肾病（IgAN）患者的肾脏病理特征及其与临床表现的关系.方法 对1993年1月至2009年10月肾活检确诊为IgAN,且表现为少量蛋白尿（＜1 g/24 h）和（或）血尿,Scr＜133 μmol/L的患者的临床和病理资料进行回顾性分析.病理学分级参照Lee分级及Katafuchi半定量积分标准.应用多因素logistic回归法分析肾脏病理损伤的危险因素.结果 符合入选标准共316例,男123例,女193例,肾穿时年龄（33.10±10.69）岁.蛋白尿伴血尿占84.5%、单纯血尿占7.6%、单纯蛋白尿占7.9%.16.5%患者伴有高血压.CKD1、2、3期分别占76.9%、20.9%和2.2%.LeeⅢ级及以上患者占31.3%.52.8%患者有不同程度肾小球硬化;20.3%伴新月体形成;22.5%伴小管萎缩;16.8%有间质纤维化;24.7%有血管病变.肾小球硬化积分与估算肾小球滤过率（eGFR）呈负相关;与蛋白尿及平均动脉压（MAP）呈正相关.肾小管间质病变积分与eGFR及血红蛋白（Hb）呈负相关;与尿蛋白量呈正相关.血管病变积分与MAP呈正相关;与eGFR呈负相关（均P＜0.05）.多因素logistic回归分析结果显示,肾活检时尿蛋白量（OR=8.564,P＜0.01）、Scr（OR=1.031,P＜0.01）及Hb（OR=0.975,P＜0.01）是肾脏病理损伤（LeeⅢ级以上）的独立危险因素.结论 部分表现为少量蛋白尿和（或）血尿IgAN患者的病理改变并不轻,且肾功能已减退.尿蛋白量、Scr、Hb是预测肾脏病理损伤程度的独立危险因素.肾活检对这些患者明确诊断、判断病情和预后、制定个体化治疗方案十分重要.

Objective To clarify the relationship between clinical manifestation and pathological features of IgA nephropathy （IgAN） patients with mild proteinuria and/or hematuria.Methods Clinicopathological data from 316 biopsy-proven IgAN cases （proteinuria〈1 g/24 h and/or hematuria, and Scr〈133 μmol/L） from our hospital between January 1993 and October 2009 were studied retrospectively. The renal histopathology was quantified according to Lee＇s grading and Katafuchi＇s semi-quantitative standard, and the risk factors for renal pathological lesions were evaluated using multifactor logistic regression analysis. Results Among these 316 patients, 123 were male and 193 patients were female. The mean age at the time of renal biopsy was （33.10±10.69） years old. Clinical features were found as follows： hematuria with proteinuria was found in 267 patients （84.5%）, isolated hematuria in 24 patients （7.6%）, and isolated proteinuria in 25 patients （7.9%）. 16.5% of patients had hypertension. The percentages of CKD stage Ⅰ, Ⅱ, Ⅲ were 76.9%, 20.9% and 2.2%, respectively. 31.3% of patients presented Lee＇s grade Ⅲ or more severe.52.8% of patients had various degrees of glomerulosclerosis. Crescent formation was observed in 20.3% of patients. 22.5% of patients showed tubular atrophy;16.8% showed interstitial fibrosis and 24.7% also had renal vascular lesions. The extent of glomerulosclerosis was negatively correlated with eGFR levels, but positively correlated with the amount of proteinuria and mean arterial pressure （MAP） level （P〈0.05）. The score of tubulointerstitial lesion was positively correlated with the amount of proteinuria and negatively correlated with eGFR and hemoglobin （Hb）level （P〈0.05）. The degree of renal vascular lesion was also correlated to MAP level positively and eGFR level negatively （P〈0.05）. Multifactor logistic regression analysis revealed that proteinuria, Scr and Hb at the time of renal biopsy were independent risk factors for severe renal pathological lesions （Lee＇s grade Ⅲ or more severe） with odds ratio of 8.564, 1.031 and 0.975 respectively （all P〈0.01）. Conclusions Severe renal histological lesions and decrease of renal function may be seen in some IgAN patients with mild proteinuria and/or hematuria. The levels of proteinuria,Scr and Hb are the independent risk factors for severe renal pathological lesions. Renal biopsy is important in these patients in order to make diagnosis and individual treatment.