Comparison between virology and serology for the follow-up of cytomegalovirus infection in heart transplant recipients

This work aimed to evaluate serology in relation to non-quantitative polymerase chain reaction (PCR) and pp65-antigenemia for the follow-up of cytomegalovirus (CMV) infection in heart transplant recipients. Besides conventional serology, antibodies were also detected by immuno Western blotting (IWB) and by recombinant enzyme immunoassay (EIA). Twenty-five CMV infected patients were evaluated. Twelve of them experienced symptomatic infection and underwent 9-(1,3-dihydroxy-2-propoxymethyl) guanine (DHPG) therapy whereas 13 asymptomatic infections were not treated. Risk factors for developing a symptomatic infection were a high antigenemia level as well as a high and delayed IgM response to ppUL44 (p52) and a low IgG response to the virus. PCR was the most sensitive procedure for detecting CMV infection (24 out of 25 infected patients and a mean time of 40 days after transplant), followed by IWB-IgM (23 patients and 40 days) and antigenemia (22 patients and 41 days). All the 12 symptomatic infections could be detected by one of the three above-mentioned methods, whereas no single test could identify all the 13 asymptomatic infections. The combination of two tests that could detect all the 25 CMV infections was PCR plus a serological procedure (IWB-IgM or recombinant EIA for p52) and pp65-antigenemia associated with IWB-IgM. As PCR results did not correlate with the onset of CMV symptomatic infection, the present data indicate that the most rational follow-up for CMV infection in heart transplant recipients can be obtained by antigenemia and IWB-IgM.