EVALUATION OF PCR PRIMERS FOR EARLY DIAGNOSIS OF CYTOMEGALOVIRUS-INFECTION FOLLOWING LIVER-TRANSPLANTATION

The availability of microbiologic methods that detect early replicatio n of cytomegalovirus (CMV) posttransplantation will enhance the proces s of initiating preemptive antiviral therapy prior to the appearance o f CMV disease, Using PCR techniques we sought to determine which regio n of the CMV genome present in peripheral blood leukocytes (PBLs) or s erum provides the highest sensitivity for the detection of CMV posttra nsplantation, Blood samples were prospectively collected weekly for at least 8 weeks from a cohort of 21 consecutive liver transplant recipi ents not receiving anti-CMV prophylaxis. Results of PCR assays were co rrelated with recovery of CMV in cell cultures and histopathological f indings from biopsy specimens of infected organs to assess clinical sy mptomatic infection, Of 148 specimens, primer pairs directed to the Hi ndIII-X fragment region of CMV detected target DNA with a 94% sensitiv ity, compared to an 87% sensitivity with primer pairs directed to EcoR I fragment D, 32% sensitivity with primer pairs directed to the immedi ate-early antigen 1 gene (IEA1 gene), and 20% sensitivity with primer pairs directed to the major immediate-early (MIE) gene, The performanc e characteristics in terms of the sensitivity of primers for amplifyin g CMV DNA associated with symptomatic infection ranged from 100% (Hind III-X) to 20% (MIE gene); however, specificity was inversely related ( HindIII-X, 45%; MIE gene, 91%) to primers directed to these gene targe ts, When HindIII-X and EcoRI-D primer sets were used, CMV DNA from PBL s was a more sensitive target than CMV DNA from serum for the early de tection of symptomatic CMV infection (17 versus 12 days), Importantly, CMV DNA was not detected in five patients with no evidence of this vi ral infection, In conclusion, primers directed to the HindIII-X fragme nt region were the most optimal for the early detection of CMV DNA in PBLs and sera from symptomatic liver transplant recipients.