Urine fibrin degradation products in detection and management of acute and chronic renal transplant rejection.

Detection of rejection by serial determinations of urine FDP using the latex agglutination slide test proved to be a reliable, simple and inexpensive method. In the absence of infection, clinical and biochemical acute rejection was preceded by a two-titer rise in excretion of urine FDP in 80% of 26 patients studied. It was not useful in predicting rejection in 44 stable long-term allograft recipients, although persistent elevation of urine FDP after anti-rejection therapy in these patients or those in the immediate post-transplant period implies ongoing rejection. Maintenance immunosuppression should be continued in these patients, but repeated high-dose steroid therapy should be limited because of their poor-term prognosis. Persistent increase in urine FDP may allow selection of those patients who would benefit from a trial of anticoagulant or antiplatelet therapy.