Subtypes of acute postinfectious glomerulonephritis: A clinico-pathological correlation
The case records and histopathology of 42 adults with the characteristic light and electron microscopic features of Acute Postinfectious Glomerulonephritis (APGN) were studied. The biopsies were divided into three subtypes depending on the form and distribution of subepithelial 'humps' and other immune-complex deposits on electron microscopy (EM): the 'starry sky', 'garland' and 'mesangial' patterns. There was no significant difference between the three subtypes with regard to age, hypertension, creatinine, anti-streptolysin 0 titer and low serum complement levels on presentation. The 'garland' subtype had significantly more proteinuria than both the 'starry sky' (p = 0.04) and 'mesangial' (p = 0.003) subtypes. The 'mesangial' pattern had a lesser degree of cellular proliferation and leukocytosis in the glomeruli than the other subtypes. The 'starry sky' subtype was present in 4 of the 5 cases of crescentic nephritis and in 6 of the 7 patients with a chronic course. Our study suggests that the higher degree of proteinuria in the 'garland' subtype and the chronic course of the 'starry sky' subtype are the main clinical features that distinguish the three histological subtypes. Our patients, from a developing community with poor socio-economic conditions, had a poor prognosis.