Journal of Ultrasound in Medicine, Vol 9, Issue 9 503-510, Copyright © 1990 by American Institute of Ultrasound in Medicine
Detection of rejection in renal allografts. Evaluation with duplex sonography and DTPA renal scintigraphy with kidney/aorta perfusion ratios
S. Don, K. K. Kopecky, M. M. Tuli and A. R. Siddiqui
Department of Radiology, Indiana University Medical Center, Indianapolis 46223.
Duplex sonography and technetium-99m DTPA renal scintigraphy have been used
to distinguish acute rejection from other forms of renal allograft
dysfunction. In this study, duplex sonography and renal scintigraphy were
compared as methods to detect rejection. Eighty-four episodes of renal
allograft dysfunction that had concurrent duplex sonography and renal
scintigraphy over a 17-month period were reviewed. During the duplex
sonography examinations the resistive index (RI) was measured from the
renal cortex. Scintigrams were evaluated for allograft perfusion and
function. The kidney to aorta (K/A) ratio was calculated from the upstroke
of the perfusion curve. All diagnoses were established by clinical
criteria. Histologic proof was available in 49 cases. There were two
episodes of hyperacute rejection, 30 episodes of acute rejection, 14
episodes of chronic rejection, and 38 episodes of dysfunction without
rejection. Using an RI greater than or equal to 0.70, the sensitivity and
specificity for detecting acute rejection were 90% and 76%, respectively,
compared with 37% and 76% for renal scintigraphy. The K/A ratio was not
helpful in the diagnosis of rejection.
