Correlation analysis of intrarenal arteriolar hyalinosis in IgA nephropathy with mild proteinuria and without hypertension

Objective To explore the correlation of intrarenal arteriolar hyalinosis (AH) with clinical and pathological indicators in IgA nephropathy (IgAN) with mild proteinuria and without hypertension. Methods Retrospective analysis was performed in patients with newly biopsy-confirmed IgAN between January 1, 2010 and December 31, 2014 in the Department of Nephrology, Chinese PLA General Hospital. The patients′ clinical data during the week before renal biopsy were collected. Pathological lesions were evaluated according to the updated Oxford Classification. Patients were divided into intrarenal AH group and non-AH group. Clinical and pathological indictors were compared between the two groups. The correlation of intrarenal AH with clinical and pathological indicators was analyzed using multivariant logistic regression method. Results A total of 126 IgAN cases without hypertension were enrolled, among whom 44 (34.92%) cases had intrarenal AH. All the 126 cases had proteinuria ≤1 g/d. The age, body mass index, serum uric acid, urea nitrogen, and creatinine were higher in intrarenal AH group than in non-AH group (P<0.05). And eGFR of intrarenal AH group was lower than that of non-AH group (P<0.05). There were significant differences in chronic kidney disease stages and tubular atrophy/interstitial fibrosis between the two groups (z=3.290, P=0.001; z=3.293, P=0.001). Multivariant logistic regression analysis showed that intrarenal AH of IgAN was correlated with male (OR 3.08, 95%CI 1.03-9.18), each age increase by 10 years (OR 3.02, 95%CI 1.79-5.07), each body mass index increase by 10 kg/m2 (OR 7.08, 95%CI 1.54-32.42), and tubular atrophy/interstitial fibrosis (OR 5.96, 95%CI 2.11-16.80). Conclusion It is not uncommon for IgAN patients with mild proteinuria and without hypertension to have intrarenal AH. Gender, age, body mass index, and tubular atrophy/interstitial fibrosis were correlated with intrarenal AH of IgAN. Key words: IgA nephropathy; Intrarenal arteriolar hyalinosis; Pathology