title: IgA nephropathy occurring in the context of previous acute glomerulonephritis.
abstract: A 37-year-old female presented with acute onset of glomerulonephritis 10 days following an upper respiratory infection. Serum complement components were depressed and proteinuria exceeded 3.0 g daily. Renal biopsy revealed granular staining of IgG and C3 along the basement membrane as well as small amounts of IgA in a linear pattern. Gradual resolution of symptoms was followed by recrudescent proteinuria 2 years later. Renal biopsy at this time revealed large deposits of IgA in a mesangial staining pattern consistent with a diagnosis of IgA nephropathy. Possible mechanisms for this unusual morphologic transformation include enhanced mesangial permeability as well as mesangial sequestration of an exogenous antigen.
mesh_terms: D000208:Acute Disease; D000328:Adult; D005260:Female; D005921:Glomerulonephritis / Q000503:physiopathology; D005922:Glomerulonephritis, IGA / Q000175:diagnosis* / Q000473:pathology; D006801:Humans; D007070:Immunoglobulin A / Q000032:analysis; D007074:Immunoglobulin G / Q000032:analysis; D007678:Kidney Glomerulus / Q000473:pathology / Q000648:ultrastructure; D008854:Microscopy, Electron
chemical_list: D007070:Immunoglobulin A; D007074:Immunoglobulin G