Evaluation of acute renal failure in bacterial allograft pyelonephritis using abdominal CT and graft biopsy.

The causes of acute renal failure in bacterial allograft pyelonephritis were evaluated using abdominal CT and graft biopsy. Twenty-one recipients, who showed a poor response to antibiotic therapy, comprised this study group. The diagnostic approach taken with this poor responder group was first to perform abdominal CT. If a focal lesion was identified on abdominal CT, a diagnosis of acute focal bacterial nephritis or renal abscess was made. If no focal lesion was found, a graft biopsy was performed for diagnosis. Abdominal CT revealed focal lesions in 9 of the 21 recipients, and renal biopsy showed superimposed acute rejection in 8 of the 12 recipients biopsied. In conclusion, acute renal failure in allograft pyelonephritis is associated with not only severe infection but also a superimposed acute rejection process. Therefore, imaging study and graft biopsy are recommended in the poor responder group.