Clinical and pathology features of IgA nephropathy with active tubular interstitial lesions

Objective To investigate the clinical and pathological characteristics of IgA nephropathy (IgAN) in association with active tubular interstitial lesions. Methods 148 patients who were diagnosed as IgAN by renal biopsy and admitted to Zhejiang Provincial People's Hospital from March 2014 to December 2014 were enrolled. They were divided into IgAN with active tubular interstitial lesions group (IgAN-ATIL group, 23 patients) and IgAN without active tubular interstitial lesions group (control group, 125 patients). Clinical and pathological characteristics were retrospectively analyzed. Multivariate logistic regression analysis was used to analyze the influence factors. Results The prevalence of ATIL in 148 IgAN patients was 15.5%. IgAN-ATIL group showed an older average age and more higher proportion of medication history (antibiotics, diuretics, nonsteroidal anti-inflammatory drugs, etc) than those in control group. There were significant differences in Alb, eGFR, Scr, BUN, 24-hour urinary protein quantity, urinary NGAL and urinary RBC count between two groups (P＜0.05, respectively). A moderate of tubulointerstitial lesions of IgAN-ATIL group was shown, while the control group was mainly mild lesions. Multivariate logistic regression analysis showed that age, medication history and the urinary NGAL level were independent risk factors of IgAN-ATIL. Conclusions IgAN patients with active tubular interstitial lesions had more severe clinical manifestations and chronic interstitial lesions. The age, medication history (antibiotics, diuretics, nonsteroidal anti-inflammatory drugs, etc) and the urinary NGAL level were independent risk factors of IgAN-ATIL.