IgM nephropathy in India: a single centre experience.

<bold>Objective: </bold>To find out the incidence and natural history of IgMN in India.<bold>Methods: </bold>Renal biopsies of children ≤12 y age of last 6 y were retrospectively evaluated. Their clinical and biochemical presentation were correlated. Patients with systemic diseases/disorders were excluded from the study.<bold>Results: </bold>Immunoglobulin M nephropathy (IgMN) constituted 11.9% (n = 28) of 236 renal biopsies. Mean age was 10 y, predominant in boys (n = 24), most of the patients presented with proteinuria and edema. The most common associated histopathological finding was mesangial proliferative glomerulonephritis (MePGN) in 60.7% (n = 17) followed by minimal change disease (MCD) in 28.6% (n = 8) and focal segmental glomerulosclerosis (FSGS) in 10.7% (n = 3). In 85.7%, IgM appeared as the sole immunoglobulin deposit mainly in mesangial regions, followed by accompanied C3 in 3.6% (n = 1) and C1q + C3 in 10.7% (n = 3) biopsies.<bold>Conclusions: </bold>IgMN was observed in 11.9% biopsies with commonest morphology of MePGN followed by MCD and FSGS; proteinuria was bad prognosticator in addition to FSGS and co-deposition of other immunoglobulins had no significance. [ABSTRACT FROM AUTHOR]