Feline renal allograft rupture.

A 5-year-old domestic shorthair cat, that had undergone renal transplantation 3 months earlier, was evaluated after an acute episode of abdominal discomfort. Abdominal ultrasound revealed an enlarged renal allograft (5.5 cm; reference range, 3.2-4.2 cm) with pyelectasia (renal pelvis=3.7 mm; reference range, 1-2mm). Based on the ultrasonographic appearance of the allograft, primary rule-outs for the renomegaly included hypertrophy and allograft rejection. The ureter and urethra were dilated and a mild amount of abdominal effusion was noted. Thirty-six hours after admission, the cat became acutely hemodynamically unstable and was diagnosed with a hemoabdomen. Review of the original ultrasound revealed a peri-renal hematoma. During emergency laparotomy, ruptures in the cortex of the transplanted kidney were found to be the source of hemorrhage. Immediately following surgery, the cat experienced cardiorespiratory arrest, and resuscitation was not successful. Necropsy and histopathology revealed rupture of the renal allograft. This is the first reported case of renal allograft rupture in a cat, whereas allograft rupture has been reported in human renal transplant patients.