Utility of Biopsy in Kidney Transplants With Delayed Graft Function and Acute Dysfunction D.M. Silva, J.P. Garcia, A.R. Ribeiro, F.J. Veronese, M.I. Edelweiss, L.F. Gonçalves, and R.C. Manfro ABSTRACT Renal biopsy is currently the gold standard to assess the causes of renal allograft dysfunction. In the present study, we prospectively assessed the role of the renal allograft biopsy in the diagnosis and treatment of renal allograft dysfunction. Seven hundred and fifteen biopsies were performed in 399 patients. The anatomopathological results in group 1 (delayed graft function) were: 60.4% acute tubular necrosis, 17.6% acute rejection, 4.3% calcineurin inhibitor toxicity, and 17.7% other diagnoses; in group 2 (acute graft dysfunction): 42.3% acute rejection, 22% acute tubular necrosis, 8.4% calcineurin inhibitor toxicity, and 27.3% other diagnoses. Among patients with delayed graft function, 42.2% of biopsies led to a change in the treatment. In 60.5%, the biopsy of patients with acute dysfunction led to a change in the patient management. In our series, the result of the biopsy disagreed with the clinical diagnosis in 39.6% and 57.7% of cases, respectively. These results demonstrated that renal graft biopsy remains an indispensable tool for the accurate management of kidney transplant patients. R ENAL BIOPSY IS currently the gold standard to assess the cause of renal allograft dysfunction, 1 in- cluding ischemia-reperfusion injury, acute and chronic im- munological mediated damage, immunosuppressant drug toxicity, and infections. 2,3 The clinical presentations of delayed graft function (DGF), acute or chronic allograft dysfunction, and proteinuria can result from various inju- ries; an accurate diagnosis is a key factor for successful management. 4,5 However, over the last years, great im- provements in transplantation practice may have modified the need for sampling of the transplanted tissue. 6,7 In the present study, we prospectively assessed the role of the renal allograft biopsy in the diagnosis and treatment of renal allograft dysfunction. PATIENTS AND METHODS We analyzed data from prospective records of renal allograft biopsies performed in our institution from 1991 through 2004. The records consisted of the indication for biopsy and the physician’s clinical diagnosis as recorded before the pathological result. In addition, we evaluated the adequacy of the specimen, the biopsy result, and the treatment(s). The pathologists analyzing the biop- sies were blinded as to the clinical data. The percentage of agreement between the clinical and the pathological diagnoses versus the percentage of biopsies that resulted in changes in the patients’ care was evaluated. We analyzed the age, gender, race, previous kidney transplantations, donor type (cadaveric/living), and time from the transplantation until the biopsy. Data are presented as percentages, mean values  SD, or medians. Chi-square or ANOVA tests were used to assess the statistical analysis. P  .05 denoted statistical significance. RESULTS Seven hundred and fifteen biopsies were performed in 399 patients (a mean of 1.79 biopsies per patient). The patients’ mean age was 41  11.5 years, and 55.4% were men, with 81.2% of Caucasian ethnicity and 15.8% African-Brazilian. Nine percent of patients had undergone 1 previous kidney transplantation, and 79.2% received a cadaveric organ. The main biopsy indications for group 1 were DGF (353; 49.4%), and for group 2 acute allograft dysfunction (238; 33.3%), chronic allograft dysfunction (90; 12.6%), or other reasons (34; 4.7%). The first 2 conditions included 591 biopsies. There was no statistical difference as to the age, race, gender, or donor type. The biopsies were performed earlier in the first group (mean, 35 days) than in the second From the Division of Nephrology, Kidney Transplant Program, Hospital de Clı´nicas de Porto Alegre, UFRGS Medical School, Porto Alegre, RS, Brazil. Address reprint requests to Dr Roberto C. Manfro, Division of Nephrology, Hospital de Clı´nicas de Porto Alegre, 2350 Rua Ramiro Barcelos St, 90035-903 Porto Alegre, RS, Brasil. E-mail: rmanfro@hcpa.ufrgs.br 0041-1345/07/$–see front matter © 2007 by Elsevier Inc. All rights reserved. doi:10.1016/j.transproceed.2007.01.008 360 Park Avenue South, New York, NY 10010-1710 376 Transplantation Proceedings, 39, 376 –377 (2007)