Histopathologic evaluation and complications of allograft biopsies in renal transplant recipients

Renal transplantation has become the treatment of choice for most patients with end-stage renal disease. Renal allograft biopsy is the most important technique in diagnosis of renal transplant dysfunction. Doppler sonography is a useful technique to diagnose renal transplant complications and also for follow-up of rejection. Histopathologic results and complications of biopsy, resistive index (RI) of patients diagnosed as acut rejection, chronic allograft nephropathy and calcineurin inhibitor drug toxicitiy in biopsy, correlation between serum creatinin level with renal RI of biopsy-proven grade I, II and III chronic allograft nephropathy patients, relation of acut or chronic calcineurin inhibitor drug toxicitiy with serum drug level in renal transplant patients were evaluated in this retrospective study from January 2000 till December 2007. 386 patients were included in the study and a total of 843 biopsies were performed on patients. 286 of the patients were male and 110 of them were female. The mean age was 37,8 years and varying between 6 to 71 years. 1-9 biopsies were performed on each transplant kidneys. Biopsies were performed on the 3-9344th (25.7 years) day of the transplantation. The amount of tissue was adequate in 812 biopsies, inadequate in 6 biopsies and of limited adequacy in 27 biopsies for histopathologic evaluation. Histopathologic evaluation of biopsies were standardized according to the Banff 97 working classification. Acute rejection, tubule epithel injury and chronic allograft nephropathy were frequently diagnosed. Complications of the biopsies were macroscopic hematuria in 4 biopsies, perirenal hematoma in 6 biopsies, arteriovenous fistula in 1 biopsy. Arteriovenous fistula was treated with coil embolization. In conclusion, biopsy of renal transplant patients is a safe and incidence of complications are significantly low to evaluate the renal allograft dysfunction. RI measured in duplex Doppler ultrasonography is nonspecific in diagnosis of patients, diagnosed as acute rejection, chronic allograft nephropathy and calcineurin inhibitor drug toxicitiy following biopsy. There is no correlation between developing acut or chronic calcineurin inhibitor drug toxicitiy with serum drug level. There is correlation between serum creatinin levels and renal RI of biopsy-proven grade I, II and III chronic allograft nephropathy. Key Words: renal transplantation-allograft biopsy- Doppler ultrasonography