Contribution of power Doppler sonography to the detection of renal allograft rejection in the cynomolgus monkey

RATIONALE END OBJECTIVES. TO evaluate whether a change in the power Doppler (PD) flow signals produced by the renal cortical interlobular vasculature of allografts in cynomolgus monkey transplant models is useful for the dete ction of cellular rejection and vasculopathies. METHODS. Seventy-three monkeys with life-supporting allografts (bilateral n ative kidney nephrectomy) and 20 monkeys with allografts implanted with onl y unilateral native kidney nephrectomy were examined with ultrasound that i ncluded an examination with PD, Each graft received a PD score of 3 (normal cortical blush), 2 (reduced flow, no blush), or 1 (absence of cortical flo w), and the results were compared with histology either from ultrasound-gui ded biopsy or at necropsy, RESULTS. One hundred seventy-one allograft examinations (histological and P D) were compared. Histologically normal grafts were statistically more like ly to have normal PD findings than were those with reduced flow or absent f low. Allografts with reduced flow had statistically more severe cellular re jection than those with normal how, Also, vasculopathies were present in al l three PD groups. CONCLUSIONS. Reduced renal cortical flow in the cynomolgus monkey renal all ograft indicates that more severe degrees of cellular rejection are present compared with allografts with normal how, Overlap in the histological diag noses of allografts with normal and reduced flow exists, and the finding of reduced how with PD may be prognostically important and indicates the need for tissue sampling.