CLINICAL AND VIROLOGICAL MONITORING OF HUMAN CYTOMEGALOVTRUS INFECTION IN 294 HEART TRANSPLANT RECIPIENTS

Abstract

Two hundred and ninety-four heart transplant recipients (HTR) were followed prospectively for a mean of 44.9±28.4 (range 1.0–100.8 months) after transplantation (tx). Immunosuppression was based on cyclosporine, azathioprine, and steroids, supplemented by a 7-day course of antithymocyte globulins. All patients were virologically monitored by inoculating aliquots of 2 × 105 peripheral blood polymorphonuclear leukocytes (PMNs) onto human embryonic lung fibroblasts monolayers grown in shell vials for early cytomegalovirus (CMV) identification and quantification (viremia). The same number of PMNs was cytocentrifuged onto glass slides for direct CMV pp65 antigen detection and quantification (antigenemia). Heparinized blood samples were collected weekly during the first 3 months following tx and at least twice a week if antigenemia and viremia levels were increasing. After 3 months, samples were collected if antigenemia and viremia persisted or when clinically indicated. The overall incidence of CMV infection was 53.4% (157/294). Only 32.4% (51/157) of the viremic patients required antiviral treatment because of symptomatic infection. Of the remaining 106 untreated CMV viremic HTR, 104 were asymptomatic while 2 had only mild clinical symptoms. The overall incidence of CMV infection in pre-tx CMV seropositive (CMV+) HTR was 50.9% (136/ 267); 75.7% (103/136) were asymptomatic and 24.3% (33/ 136) were symptomatic. The overall incidence of CMV infection in pre-tx CMV-seronegative (CMV-) HTR was 77.8% (21/27; P=0.007 vs. seropositive HTR). Among 22 CMV“ HTR with CMV+ donor, 20 (90.9%) had a CMV infection and all of them were symptomatic (versus 1 of 5 (20%) CMV- HTR with CMV- donor; P=0.002, Fisher's exact test). The median numbers of circulating CMV-infected PMNs detected at the onset of clinical symptoms by the antigenemia and viremia assays were 385/2 x105 and 100/2X105, respectively.