Clinical and histopathologic profile of patients with primary IgA nephropathy seen in a tertiary hospital in India

Background IgA nephropathy (IgAN) is known to have an aggressive course in Asians. There is a paucity of data regarding the Oxford classification pattern of Indian patients with IgAN. This study aims to characterize the clinical and histopathologic profile of these patients. Methods All patients diagnosed to have primary IgAN by kidney biopsy in the nephrology department from July 2009 to July 2014 were included in this study. All kidney biopsies were reviewed and the MEST score was assigned as per the Oxford classification. The clinical features and Oxford classification score of patients were characterized. Results Nephrotic range proteinuria (NRP) (65/103, 63.1%) with or without edema was the commonest presentation. 67.0% patients had eGFR 60 mL/min and 16.5% patients had eGFR <30 mL/min. Of the 103 patients, 80 (77.7%) had M1, 10 (9.7%) had E1, 45 (43.7%) had S1 and 41 (39.8%) had T1/T2 lesions by the Oxford criteria and 11 (10.7%) patients had crescents. 62 patients had eGFR 30 mL/min and follow up for at least 6 months (median -17.7 (6-65.1) months) of whom 52(83.9%) had received ACEi/ARBs and 38 (61.3%) had received immunosuppression. 11/62 (17.7%) patients developed renal worsening in this period of which 7 (11.3%) developed end stage kidney disease (ESKD). Conclusion Indian patients with primary IgA nephropathy have a unique profile. They commonly present with nephrotic range proteinuria. A significant proportion of these patients have normal renal function despite heavy proteinuria. Mesangial proliferative lesions are predominant with a paucity of endocapillary proliferation and crescents compared to other Asian populations. Immunosuppressive use is more common in Indian patients.