Cytomegalovirus antigenemia surveillance in the treatment of cytomegalovirus disease in AIDS patients

Objective: Surveillance of quantitative cytomegalovirus (CMV) antigenemia among AIDS patients with CMV treated complications in order to determine its value in assessing the response to treatment and survival. Methods: A longitudinal follow-up of antigenemia measurement at diagnosis, after induction therapy with ganciclovir or foscarnet, and every 3 months during maintenance therapy was carried out in 25 patients with CMV retinitis and in 8 with extraocular CMV disease. Positive antigenemia was defined as the presence of any amount of immunofluorescent pp65-positive leukocytes /10(5) cells. Results: Mean antigenemia values were: 77+/-148 /10(5) leukocytes at retinitis diagnosis; 45+/-114 after induction therapy; and 7+/-18 and 1.5+/-4 after 6 months and one year of therapy, respectively. Patients achieving undetectable antigenemia increased from 44% at baseline to 68% at postinduction and 80% during follow-up, Seven patients (28%) who remained free of relapses presented significant minor baseline antigenemias and became negative after induction therapy. Patients with extraocular disease showed erratic antigenemia values and absent therapeutic response. CMV blood cultures before and after induction therapy were positive in 39% and 21% of patients, respectively. Kaplan-Meier analysis revealed a significantly longer survival for patients with retinitis when compared to those with extraocular complications, and for patients with negative antigenemia after induction in comparison with those who failed to achieve it. Conclusions: Low basal antigenemia and antigenemia clearance after induction therapy are variables directly related to good response to treatment and survival. Continuous surveillance of antigenemia during treatment could permit designing of individual strategies to obtain a better response.