Double anti-neutrophil cytoplasmic antibody and anti-glomerular basement membrane antibody-positive crescentic glomerulonephritis, following SARS-CoV-2 infection

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) affects kidneys mainly in the form of acute kidney injury but rarely can cause glomerular disease. On a very rare occasion, SARS-CoV-2 infection can be associated with anti-neutrophil cytoplasmic antigen (ANCA)-associated vasculitis and anti-glomerular basement membrane glomerulonephritis (anti-GBM GN). We report a case of a 59-year-old man who presented with progressive renal failure 8 weeks after contracting the viral infection, which progressed slowly to severe renal dysfunction. Renal biopsy showed crescentic glomerulonephritis (CrGN) accompanied by interrupted linear IgG deposits along the glomerular basement membrane (GBM) on immunofluorescence (IF) staining with associated mild acute tubular injury. The serology for anti-myeloperoxidase (MPO), as well as anti-GBM antibodies, was positive. He was treated with steroid and pulse intravenous cyclophosphamide, following which there was a significant improvement in the renal function and serological resolution of both the antibodies 6 months post-treatment. To the best of our knowledge, this is the first reported case of "double-antibody " positive CrGN following SARS-CoV-2 infection.