Tanaka Kayu, Moriyama Takahito, Iwasaki Chihiro, Takei Takashi, Nitta Kosaku
Department of Medicine, Kidney Center, Tokyo Women's Medical University, Kawada-cho 8-1, Shinjyuku-ku, Tokyo, 162-8666, Japan.
Clin Exp Nephrol. 2015 Oct;19(5):815-21. doi: 10.1007/s10157-014-1068-9. Epub 2014 Dec 5.
The effects of hematuria on the outcome of IgA nephropathy (IgAN) remain unknown and treatment of IgAN with severe hematuria is controversial.
Eighty-eight IgAN patients with proteinuria <0.5 g/day and who had not received corticosteroids, immunosuppressive agents, or undergone a tonsillectomy were divided into two groups: (1) patients with low (<20/high-power field [HPF]) urinary red blood cell (U-RBC) counts (L-RBC group, n = 48); and (2) patients with high (≥20/HPF) U-RBC counts (H-RBC group, n = 40). Clinical and histological findings, renal survival rate and risk factors for progression were analyzed.
The male ratio and blood pressure were significantly higher in the L-RBC group. Median proteinuria, mean estimated glomerular filtration rate and histological findings according to Oxford classifications were similar. During the 5 years after renal biopsy, the median amount of proteinuria remained at <0.5 g/day or g/g creatinine in both groups, and the median U-RBC decreased to <10/HPF in both groups without any intensive therapy. The 15-year renal survival rate, estimated using the Kaplan-Meier method, was 100 % in the H-RBC group, but decreased to 83.4 % in the L-RBC group, although it was not significant. The treatment of inhibitors of renin-angiotensin system (RAS inhibitors) decreased the risk for progression by Cox regression analysis (hazard ratio: 0.14, p = 0.027).
Severe hematuria at the time of biopsy naturally improved without any intensive therapy, and there were no negative effects of hematuria on the outcome of IgAN with mild proteinuria. Its prognosis was relatively good, and the treatment of RAS inhibitors might prevent from progression.
血尿对IgA肾病（IgAN）预后的影响尚不清楚，IgAN伴严重血尿的治疗存在争议。
88例蛋白尿<0.5g/天且未接受过皮质类固醇、免疫抑制剂治疗或扁桃体切除术的IgAN患者被分为两组：（1）低（<20/高倍视野[HPF]）尿红细胞（U-RBC）计数患者（低红细胞组，n = 48）；（2）高（≥20/HPF）U-RBC计数患者（高红细胞组，n = 40）。分析临床和组织学表现、肾脏存活率及进展的危险因素。
低红细胞组男性比例和血压显著更高。根据牛津分类法，两组的蛋白尿中位数、平均估计肾小球滤过率和组织学表现相似。肾活检后5年期间，两组蛋白尿中位数均维持在<0.5g/天或g/g肌酐，且两组U-RBC中位数均降至<10/HPF，无需任何强化治疗。采用Kaplan-Meier法估计，高红细胞组15年肾脏存活率为100%，低红细胞组降至83.4%，虽无统计学意义。经Cox回归分析，肾素-血管紧张素系统抑制剂（RAS抑制剂）治疗降低了进展风险（风险比：0.14，p = 0.027）。
活检时的严重血尿未经任何强化治疗自然改善，且血尿对轻度蛋白尿的IgAN预后无负面影响。其预后相对良好，RAS抑制剂治疗可能预防疾病进展。
