[Anti-MBG crescentic glomerulonephritis with negative immunofluorescence: case report and literature review]

Anti-glomerular basement membrane (anti-GBM) antibody disease is a rapidly progressive glomerulonephritis characterized by (i) positivity to anti-GBM in serum reacting with a specific antigen present in type IV collagen at both the glomerular and alveolar levels (ii) presence of crescent on light microscopy and positivity to linear deposits of IgG and C3 on immunofluorescence. In the classic variant, the clinic is that of a nephro-pneumological syndrome but there are variants. Rarely, the glomerular damage is pauci-immune. We describe a case of a variant in which there is anti-MBG positivity in serum but negative immunofluorescence and offer a review of the literature and potential treatments.