Clinicopathological features of IgA nephropathy associated with malignant hypertension and their correlation to renal vascular lesions / 中华肾脏病杂志

ABSTRACT

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 eases 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 endpeint 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%), hyperurieacidemia (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 foUow-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.