Relapse with transformation of lupus nephritis in a transplant kidney.

Lupus nephritis is a constellation of different renal histologies, characterized by an immune complex mediated glomerular disease. Histological transformation in lupus nephritis usually occurs from a mild mesangial proliferative glomerulonephritis to a more aggressive diffuse proliferative lesion. We present a case of relapsed systemic lupus erythematosus (SLE) in a renal transplant recipient in which there was a histological transformation from the original diffuse proliferative lupus nephritis in the native kidneys to a membranous lupus nephritis in the renal transplant.