Early acute rejection of renal homografts: a characteristic clinical syndrome.

Seven of 74 patients with early functioning cadaveric renal homografts developed acute oliguric renal failure after the second but before the ninth day post-transplantation. The syndrome characteristically begins with an abrupt and simultaneous decrease in creatinine clearance, urine volume and urine sodium concentration. After a variable period and despite a reduction in immunosuppressive therapy, a diuretic phase ensues and renal function is restored. Complications associated with the syndrome include groin hematoma, pulmonary edema and renal rupture with shock. Renal rupture does not require nephrectomy: if the hemorrhage is controlled, the transplanted organ will resume function. Angiographic studies show normal nephrograms, stretched arterial vasculature and filling defects in the veins. Percutaneous renal biopsy shows interstitial edema and hemorrhage, venous congestion and tubular necrosis. Evidence is presented to support the hypothesis that this is a form of rejection occurring as the result of injury to the renal venous system.