Early detection of hepatitis C allograft reinfection after orthotopic liver transplantation: A molecular and histologic study

After orthotopic liver transplantation (OLT), patients with chronic hepatit is C virus (HCV) infection show nearly universal persistence of viremia and reinfection of the liver, but identifying the point at which the liver is reinfected morphologically can be difficult. One tool that may potentially be useful to detect reinfection is reverse transcriptase-polymerase chain r eaction (RT-PCR), which has proven to be highly sensitive for detecting HCV RNA in formalin-fixed paraffin-embedded liver tissue. Our purpose was to g ain insight into the time frame of HCV reinfection by assaying for HCV RNA in serial posttransplant liver biopsy specimens. Our study population consi sted of 14 patients who underwent liver transplantation for hepatitis C and had confirmed HCV RNA in pretransplant serum, absence of HCV RNA in donor livers, and available consecutive posttransplant liver allograft specimens. We performed RT-PCR for HCV RNA in serial posttransplant liver biopsy spec imens, beginning at 1 week until at least one biopsy from each tested posit ive. HCV RNA was detected in liver tissue by RT-PCR in 1-week post-OLT live r samples in 6 of 14 (42.8%) patients, the earliest being 5 days post-OLT. Eventually, each of the remaining eight samples became RT-PCR positive as w ell; the first detections occurred in these at 3 weeks (three cases), 4 wee ks (three cases), 48 weeks (one case), and 144 weeks (one case). Histologic identification of hepatitis C recurrence was relatively insensitive in rel ation to these molecular data. These data suggest that (1) HCV RNA reinfect ion is nearly universal after liver transplantation in patients with chroni c hepatitis C infection, (2) molecular reinfection by HCV occurs at a varia ble interval post-OLT, with the majority of allograft livers reinfected as early as 1 week, and (3) morphologic features of hepatitis C are usually ap preciable at the time of "molecular" recurrence.