Primary IgA nephropathy in north India: is it different?

Background Immunoglobulin A (IgA) nephropathy is the most common glomerulonephritis worldwide, but has a variable geographic distribution. The bulk of the disease burden is borne by Asian countries. However, its exact prevalence or clinicopathologic spectrum in India is not well documented.

Methods This cross sectional study analysed the renal biopsy findings and clinical features at presentation in 66 patients of primary IgA nephropathy diagnosed over a period of 2 years (2007–2008). The results were compared with studies from other centres in the country and elsewhere.

Results IgA nephropathy comprised 8.1% of all native kidney biopsies. The mean age of the patients was 29.9 years with a male:female ratio of 4.4:1. Most patients presented with renal failure and a significant percentage (23%) also had nephrotic range proteinuria. Renal biopsies were classified by the Haas classification and were further scored by the MEST scoring system of the Oxford classification. By Haas classification, 41 cases (62%) showed advanced sclerotic lesions of class V. Active crescents (cellular or fibrocellular) were seen in 42% of cases, and 26% of cases showed endocapillary proliferation. Serum creatinine values were highest in the presence of proliferative lesions. MEST scoring of the Oxford classification was not applicable in approximately 18% of cases because of the presence of advanced sclerotic lesions. On immunofluorescence, the majority of the cases showed both mesangial and membranous positivity for IgA antisera. Electron microscopy revealed para-mesangial location of immune complex deposition in the majority of the cases. It also showed glomerular basement membrane abnormalities in two cases.

Conclusion Comparison of clinical and pathological features revealed that this disease presents as an advanced disease in much younger individuals in this study compared to other studies. Elucidation of the underlying factors may have immense therapeutic implications.