Long term study of mesangial proliferative glomerulonephritis with IgM deposits

Twenty-six cases of Mesangial Proliferative Glomerulonephritis and diffuse IgM deposits were studied. Nine had nephrotic syndrome; 8 minimal urinary abnormalities; 7 asymptomatic proteinuria; 2 recurrent haematuria. Immunofluorescence revealed granular mesangial deposits in 14 cases and interrupted linear deposits in the others, chiefly along the capillary walls. In the latter group the clinical picture was mainly nephrotic syndrome or asymptomatic proteinuria. The clinical course is favourable: 7 cases recovered; 12 improved; 7 did not show any change. No progression of renal lesions was observed. Despite uniform histological features, this nephropathy is unlikely to be a unique disease, but in our opinion it should be considered separately from other glomerulopathies.