伴恶性高血压IgA肾病的临床病理特征及其与肾血管病变的相关性

目的 分析伴恶性高血压IgA肾病（IgAN-MHT）的临床病理特征并探讨其与肾血管病变的相关性。 方法 从我科1997年4月至2007年5月间肾活检确诊的2000例原发性IgA肾病中筛选出29例IgAN-MHT患者，收集其临床、病理及预后资料。半定量分析肾小球、肾小管间质及血管（肾内微动脉、小动脉）的病理改变，包括436条入球动脉、124条小叶间动脉及5条弓形动脉。分析血管病变与肾脏病理改变、临床指标及预后的相关性。终点事件为基线Scr水平增加1倍或终末期肾病。 结果 原发性IgAN中MHT发生率约为1.5%。IgAN-MHT患者的临床表现主要为肾功能不全（100%）、高尿酸血症（62.7%）、高三酰甘油血症（51.7%），尿蛋白量（24 h）平均为2.8 g。常见肾脏病理改变为中度系膜细胞增殖、重度肾小球硬化、重度间质炎细胞浸润、重度肾小管萎缩及间质纤维化。IgAN-MHT患者的肾内小动脉（弓形动脉和小叶间动脉）及微动脉（入球动脉）均可受累。常见肾内血管病变特点为动脉闭塞、动脉中膜增厚、增生性动脉内膜炎（洋葱皮样改变、黏液样变性）、血管壁透明样变性，其中以肾内动脉闭塞为主（86.2%）。微动脉病变程度与年龄、总蛋白水平呈负相关；血管闭塞程度与尿酸水平呈正相关。平均随访21.1个月（1~84个月），14例患者达到终点。肾内微动脉病变是IgAN-MHT患者预后不良的主要危险因素(RR = 10.21，95%CI = 1.16~89.67)。 结论 IgAN-MHT的主要临床特点是肾功能不全；主要病理特征是以动脉闭塞为主的微动脉病变。微动脉病变是IgAN-MHT患者预后不良的主要危险因素。

Clinicopathological features of IgA nephropathy associated with malignant hypertension and their correlation to renal vascular lesions

Objective To explore the clinicopathological features of IgA nephrolpathy associated with malignant hypertension (IgAN-MHT) and to analyze their correlation with renal vascular lesions. Methods Twenty-nine patients of IgAN-MHT were screened from 2000 biopsy-proven cases with primary IgA nephropathy (IgAN) in our department from April 1997 to May 2007. Data of clinicopathology and follow-up of these 29 patients were collected. Semi-quantitative analysis was performed to evaluate the pathological changes. Inner lumen, outer lumen, intimal thickness, tunica media-to-internal lumen ratio of 436 arterioles, 124 interlobular arteries and 5 arcuate arteries were measured. The primary endpoint was the composite of a doubling of serum creatinine level and ESRD. Correlations of renal vascular lesions with clinical manifestation, pathological change and prognosis were examined by Spearman and Cox methods. Results 1.5% of all the IgAN patients presented malignant hypertension. The common clinical features were renal failure (100%), hyperuricacidemia (62.7%) and hypertriglyceridemia (51.7%). The average amount of urine protein excretion was 2.8 g/d. The common pathological changes were moderate mesangial proliferation, severe global sclerosis, severe interstitial inflammation and severe interstitial-tubular fibrosis. The small arteries (arcuate arteries and interlobular arteries) and arterioles (afferent arterioles) were both involved in IgAN-MHT. The characteristic lesions of intrarenal arteries included vascular occlusion, media thickening, proliferative endarteritis (onionskin lesion, musculomucoid intimal hyperplasia), hyaline arteriosclerosis, but mainly vascular occlusion (86.2%). The arteriole lesion was negatively correlated with age and total protein level; vascular occlusion was positively correlated with uric acid level. The average follow-up period was 21.1 months. Forteen patients reached the endpoint. The arteriole lesion was the main independent risk factor for the progression of IgAN-MHT (RR=10.21, 95%CI=1.16~89.67). Conclusions The main clinical feature of IgAN-MHT is renal failure. The main histological feature of intrarenal vascular lesions is occludes arterioles. Arteriole lesion is the main independent risk factor for the progression of IgAN-MHT.