IgA Staining Patterns Differentiate Between IgA Nephropathy and IgA-Dominant Infection-Associated Glomerulonephritis

Differential diagnosis of primary IgA nephropathy (IgAN) and IgA-dominant infection-related glomerulonephritis, particularly Staphylococcus infection−associated glomerulonephritis (SAGN), on a kidney biopsy sample can be challenging because of similar morphologic findings by light microscopy, immunofluorescence, and electron microscopy.1−6 The clinical management approach, however, is very different. Immunosuppressive therapy is contraindicated in SAGN because it can lead to sepsis and even death.