Anti-glomerular basement membrane disease and IgA nephropathy in a patient with previous renal cell carcinoma.

A 66-year-old Asian woman presented with severe kidney injury, microscopic haematuria and subnephrotic range proteinuria with elevated serum anti-glomerular basement membrane (anti-GBM) titre. She had a history of renal cell carcinoma. Renal biopsy revealed dual pathology with immunofluorescence showing 3+ linear glomerular IgG staining and 3+ IgA mesangial staining. Cellular crescents were present on light microscopy and electron microscopy revealed increased mesangial matrix. She was treated with plasma exchange and immunosuppression and remained in stage 4 chronic kidney disease. This case describes the coexistence of anti-GBM disease and IgA nephropathy, a phenomenon not well described in the literature. The report also explores the association of malignancy and glomerulonephritis as well as the role of genetics and the utility of human leukocyte antigen (HLA) typing in risk stratification.