[Value of renal biopsy in deteriorating graft function following renal allotransplantation].

The value of renal transplant biopsy in determining the cause of deteriorating graft function was evaluated by comparing morphologic diagnoses with clinical findings and ultimate course in a series of 104 biopsies. Transplant biopsy was a valuable tool in diagnosing acute and chronic transplant rejection. It was superior to clinical parameters, mainly in differentiating vascular transplant rejection (which is usually associated with poor prognosis) from cellular rejection (associated with a much better prognosis). Biopsy was less effective in detecting deteriorating function due to ureteral stenosis. Transplant biopsy was essential in determining the case of proteinuria, thanks to its ability to differentiate the various types of glomerular transplant lesions.