Kidney allograft biopsy: a valuable tool in assessing the diagnosis of acute rejection.

In order to determine the value of an isolated renal percutaneous biopsy in renal allografts with acute rejection, we studied 17 allograft nephrectomies, in which the histological degree of acute rejection of each of 30 Tru-cut cylinders, were compared with the histological degree of acute rejection diagnosed in 6 large fragments of each kidney considered as a whole. An accurate histological degree of acute rejection was made in 366 cylinders (71.8%). One hundred twenty-nine kidney cylinders (25.3%) were considered of a minor histological degree of acute rejection and 15 cylinders (2.9%) of a higher histological degree. We conclude that percutaneous renal allograft biopsy provides a representative picture of acute rejection histopathology but must be evaluated with other clinical and biochemical data for a correct clinical management.