[Post-infectious glomerulonephritis]

Post-infectious glomerulonephrites (GNs) include a wide spectrum of nephropathies, with known etiological agent, bacterial, parasitic, viral. Among GNs secondary to bacterial infections, post-streptococcal GN is the most frequent; nevertheless, its incidence in developed countries has decreased during the last 20 years, while some of the characteristics such as types of infection, exposed subjects, clinical and evolutionary patterns have changed. Prognosis has worsened and is correlated with some clinical and histological parameters. The viral infection-related GNs include those associated with HBV, HCV, HIV plus other rarer forms. Membranous GN (MGN), membranoproliferative GN (MPGN) and IgA nephropathy may occur in the course of HBV infection, while different GNs can be detected in relation to HCV, the most frequent being mixed cryoglobulinemic GN, a MPGN with peculiar morphological features. Multiple glomerular involvements are seen from HIV infection, the more characteristic form being the so-called HIV associated nephropathy (HIVAN), a focal segmental glomerulosclerosis with tuft collapse affecting African subjects, which starts with a nephrotic syndrome and rapidly develops into uraemia. Other GNs derive from HIV-related immunecomplexes, some with diffuse proliferative characteristics, or lupus like, with less severe clinical manifestations compared with HIVAN. Among the rare viral infections, we ultimately, mention the association between Parvovirus B19 and "collapsing" focal segmental glomerulosclerosis.