SONOGRAPHIC EVALUATION OF ACUTE PANCREATIC TRANSPLANT REJECTION - MORPHOLOGY-DOPPLER ANALYSIS VERSUS GUIDED PERCUTANEOUS BIOPSY

OBJECTIVE. Despite the increasing success of pancreatic transplantatio n for diabetes, rejection remains the most common cause of graft loss. The purpose of this study was to correlate gray-scale sonographic mor phology and Doppler resistive index (RI) with acute pancreatic transpl ant rejection as determined by percutaneous, sonographically guided bi opsy of the pancreas. SUBJECTS AND METHODS. Fifty-one sonograms of 36 patients were correlated with sonographically guided biopsies performe d for clinically suspected acute rejection. Sonographic studies consis ted of gray-scale morphologic assessment of gland size, texture, margi nal definition, peripancreatic fluid, and duct dilatation as well as m easurement of the average Doppler RI, Biopsies were performed within 4 8 hr of sonography. After localization by sonography, we performed per cutaneous biopsy with an 18-gauge automated biopsy device. RESULTS. Bi opsy findings were acute rejection (n = 40, 78%), chronic rejection (n = 2, 4%), and no evidence of rejection (n = 9, 18%), Procedure-relate d hemorrhage occurred in one patient and resolved spontaneously, Gray- scale sonographic abnormalities were present in 37 studies (73%), The most common abnormality was pancreatic enlargement (n = 23) with a sen sitivity and specificity of 58% and 100%, respectively, for acute reje ction, Loss of marginal definition occurred in nine studies with a sen sitivity and specificity of 15% and 73%, respectively, for acute rejec tion, An RI greater than or equal to 0.7 was found in 11 studies (22%) with a sensitivity of 20% and a specificity of 73% for acute rejectio n. CONCLUSION. For the diagnosis of acute pancreatic rejection, sonogr aphically guided percutaneous biopsy is superior to gray-scale and spe ctral Doppler sonography. Sonographically guided percutaneous biopsy i s a safe technique with a high success rate. Gray-scale and spectral D oppler sonography lack sensitivity, and a normal Rf should not delay b iopsy.