Correlation of radionuclide and ultrasound studies with biopsy findings for diagnosis of renal transplant rejection

Abstract

The diagnosis of early renal transplant rejection is of the utmost importance to the transplant recipient. Unfortunately, such a diagnosis is often extremely difficult to make. In an attempt to clarify this issue we retrospectively evaluated 35 patients with the presenting diagnosis of rejection for the correlation of comparable radionuclide (RN) and ultrasound (US) examinations with biopsy findings. In 21 patients with heavy interstitial mononuclear cell infiltration, 22 of 23 serial RN studies within forty-eight hours of biopsy were positive for rejection. Only 3 of 14 comparable US studies were positive for rejection. When examinations performed within approximately fourteen days were evaluated, 7 of 11 RN studies were positive for rejection, while 2 of 9 comparable US studies were positive for rejection. However, in 14 patients with mild or no interstitial cellular infiltration, only 6 of 13 RN studies were positive, while all 4 US examinations were negative. In the group evaluated at approximately two weeks, 2 of 6 RN studies were positive, while 0 of 5 US studies were positive. We conclude that the serial RN study is more sensitive than US examination for the diagnosis of acute rejection. US, however, proved valuable in the identification of transplant complications (i.e., fluid collections, ascites, and hydronephrosis).