title: Predictive value of serum complement (C3) in renal allograft rejection.
abstract: The purpose of this study was to investigate whether or not changes in serum concentrations of complement component C3 are of value in predicting the long term survival of the transplanted kidney. C3 was quantitated by radial immunodiffusion in fresh sera drawn immediately before transplantation and twice weekly thereafter from 10 recipients. Fourteen episodes of acute rejection occurred during the first 3 months postoperatively. These were diagnosed by the demonstration of graft tenderness, fever without evidence of infection and a rise in serum creatinine of 1 mg/dl in the absence of urinary or vascular obstruction. Five rejection episodes in 3 patients were associated with a fall in C3. In one of these patients, C3 returned to normal levels after the episode was reversed, and the kidney is functioning well 2 years after transplantation. In the other 2 patients, C3 remained at low levels regardless of anti-rejection therapy. Transplant nephrectomy was soon required for irreversible rejection. In contrast, only 1 episode unaccompanied by a fall in C3 was irreversible. Evidence is provided concerning the value of serial C3 complement determinations as a predictor of rejection in renal allografts. Using the variability measure Si, the cumulated standard deviation up to week i, Si > 10 not only predicts rejection but does so rather early, providing more than 90 per cent of the ideal lead time. This suggests that loss of a graft may be predicted, but this needs confirmation in additional cases.
mesh_terms: D003176:Complement C3 / Q000032:analysis*; D005500:Follow-Up Studies; D006084:Graft Rejection; D006801:Humans; D016030:Kidney Transplantation; D013997:Time Factors; D014184:Transplantation, Homologous
chemical_list: D003176:Complement C3