Scintigraphic, sonographic, and histologic evaluation of renal autotransplantation in cats

Objective-To determine scintigraphic, sonographic, and histologic changes a ssociated with renal autotransplantation in cats. Animals-7 adult specific-pathogen-free cats: 5 males, 2 females, 1 to 9 yea rs old. Procedure-Renal autotransplantation was performed by moving a kidney (5 lef t, 2 right) to the left iliac fossa. Before and at multiple times after sur gery, for a total of 28 days, cats were evaluated by B-mode and Doppler ult rasonography, scintigraphy, and renal biopsy. Results-By 24 hours after surgery, a significant decrease (42%) in mean glo merular filtration rate (GFR) and an increase in mean renal size (81% incre ase in cross-sectional area) were evident in the transplanted kidney, compa red with preoperative values. By postsurgery day 28, reduction in GFR was 2 3%. Significant changes in renal blood flow velocity were identified in bot h kidneys. Consistent changes in resistive index or pulsatility index for e ither kidney could not be identified. When all postoperative histologic dat a were combined, the histologic score, indicating degree and numbers of abn ormalities detected, for the transplanted kidney was significantly higher t han that for the control kidney. Conclusions-Significant changes in renal function, size, and histologic abn ormalities develop secondary to acute tubular necrosis in cats after uncomp licated renal autotransplantation. Clinical Relevance-Evaluation of renal size and function may be of benefit for clinical evaluation of feline renal transplant patients, whereas measur ement of the resistive index may be of little clinical value.