A Case of Recurrent Atypical Anti-Glomerular Basement Membrane Nephritis Suspicion after Renal Transplantation.

Atypical anti-glomerular basement membrane (GBM) nephritis is a rare variant of the classical anti-GBM antibody disease. Patients present with an undetectable anti-GBM antibody but show linear glomerular basement membrane staining for immunoglobulin. We present a 69-year-old man who underwent a living-donor kidney transplant. The aetiology of the renal failure was a focal segmental glomerulonephritis-like lesion resistant to immunosuppressive therapy. A renal graft biopsy revealed diffuse endocapillary hypercellularity, and mild mesangiolysis with linear GBM staining for IgG. The patient was diagnosed with atypical anti-GBM nephritis since the patient tested negative for circulating anti-GBM antibodies. Treatment involved intravenous methylprednisolone, plasma exchange, and rituximab administration. Protocol graft biopsy performed 1 year after the renal transplant showed a focal segmental glomerulonephritis-like lesion possibly progressing from endocapillary hypercellularity and mesangiolysis. These findings were similar to his native kidney biopsy findings. Although classical recurrent anti-GBM nephritis is rare when a renal transplant is performed after decreased disease activity, this case was considered as a case of recurrent atypical anti-GBM nephritis after renal transplant.