Efficacy and limitations of preemptive therapy against cytomegalovirus infections in heart transplant patients

Objectives. Cytomegalovirus (CMV) disease often represents a serious complication that promotes opportunistic infections in heart transplant recipients. In this study we evaluated the impact of preemptive gancylovir therapy, guided by pp65 antigenemia on the morbidity associated with viral reactivation. Patients and methods. We have performed a CMV infection surveillance program since March 1999, with antigenemia pp65 determinations weekly for the first 2 months biweekly in the third months, and monthly to the sixth month. Patients with pp65 antigenemia value 10 positive cells per 2 10 5 polymorphonuclear cells (PMN) were treated with intravenous gancyclovir followed by 1 month of oral gancyclovir. Results. Among the 107 patients who underwent the virological monitoring, 80 were pp65 antigenemia-positive with preemptive therapy administered in 48 cases. Five patients displayed symptomatic CMV disease (4.7% vs 18% rate in the period of 1988 to 1998 before the introduction of virologic monitoring; P .01). We observed only one case of gancyclovir-resistant pneumonia which was successfully treated with foscarnet. CMV recurrence in 10 patients required a second cycle of gancyclovir treatment. Our experience included 13 opportunistic infections (12.7%) with 11 antigenemia-positive. Conclusions. Preemptive therapy drastically reduces the incidence of CMV disease and the associated morbidity. Compared to universal prophylaxis, this approach may avoid unnecessary pharmacologic treatment in more than 50% of transplant recipients. Indeed, preemptive therapy does not fully prevent CMV disease, because it may manifest at the first antigenemia determination, and furthermore may select gancyclovir-resistant strains.