C-reactive protein in the monitoring of acute rejection after heart transplantation

Histological examination of endomyocardial biopsy (EMB) is the main technique for rejection surveillance after heart transplantation. This technique is elaborate, inconvenient for the patient, and not without complications. We prospectively analyzed whether the measurement of C-reactive protein (CRP), an acute phase protein that quickly rises when there is inflammation, can serve as a marker for immunological quiescence and as an indicator for withholding EMB. During a 6-month period, CRP was measured in all patients referred for EMB as part of the routine follow-up after heart transplantation. Acute rejection in patients with a follow-up of more than 1 year was rare (1/76). In the majority of cases, EMB was taken within the 1-year post-transplantation (170/246 = 69%). In 71/170 biopsies (42%), CRP was < or = 1; in the other 99/170 (58%), CRP was > or = 2. When CRP was < or = 1, acute rejection was diagnosed in 12/70 cases (17%). In contrast, acute rejection was found in 28/99 cases (28%) with CRP > or = 2 (P = 0.1). Although CRP is elevated more often in the presence of acute rejection, its sensitivity does not allow CRP to replace the routine performance of EMB for monitoring rejection after heart transplantation. We did, however, find a prognostic significance with regard to the effect of rejection treatment: in all acute rejections with a CRP < or = 3 (n = 11), steroids were effective.