The role of C-reactive protein in graft dysfunction after renal transplantation

PURPOSE: We investigated whether serial daily measurements of serum C-reactive protein could help differentiate episodes of transplant dysfunction due to rejection, infection, cyclosporin A nephrotoxicity or acute tubular necrosis in renal allograft recipients. MATERIALS AND METHODS: Morning serum was obtained daily from 134 patients during the first 30 days after renal transplantation. All episodes of graft dysfunction were recorded and compared to transplant biopsies. C-reactive protein concentrations were correlated with postoperative graft function and the various causes of graft dysfunction. RESULTS: All patients demonstrated an increase in C-reactive protein in response to surgery and a maximum level was reached on day 2 after transplantation. Mean C-reactive protein concentration was significantly increased for delayed (61.50 microg./ml.) compared to primary (mean 38.01) graft function (p = 0.001, Mann-Whitney U test). There were significant increases in C-reactive protein for bacterial infections other than asymptomatic bacteriuria (33.98 microg./ml), interstitial graft rejection (16.43) and acute tubular necrosis (30.50) compared to uneventful courses. C-reactive protein was unchanged for viral infections or cyclosporin A toxicity. CONCLUSIONS: Serial C-reactive protein measurements help to identify renal transplant dysfunction of different origins. However, rejection, infection and acute tubular necrosis show similar patterns of C-reactive protein increase. Thus, C-reactive protein is unable to discriminate the causes of renal graft dysfunction. Biopsy remains the gold standard for the differential diagnosis of renal allograft dysfunction.