Quantification of cytomegalovirus DNA in BAL fluid - A longitudinal study in lung transplant recipients

Study objectives: Cytomegalovirus (CMV) infection is common in patients rec eiving solid organ transplants, and it is associated with increased morbidi ty as well as risk for development of chronic rejection. A rapid and sensit ive diagnostic method would improve the therapeutic management of CMV infec tion, including the monitoring of treatment effects. We investigated whethe r longitudinal determinations of CMV DNA quantities in BAL fluid could be u seful for this purpose. Design: CMV DNA levels in 340 BAL samples from 35 consecutive lung transpla nt recipients were studied during a median of 18 months. Seventeen (49%) of the patients developed CMV disease with pneumonitis. Twenty-seven CMV dise ase episodes were diagnosed. Results: Patients with CMV disease had a significantly higher mean level of CMV copies per milliliter BAL fluid (1,120 +/- 4,379) compared with those without (180 +/- 1,177, p < 0.01). Viral load as well as acute rejection re quiring treatment (<greater than or equal to> A2) were independent risk fac tors associated with CMV disease. Differences between the groups concerning HLA-DR matching, basic immunosuppressive therapy, and CMV serologic status D/R -/+ vs D/R +/+ were not significant. A diagnostic definition of normal ity based on the mean level of all episodes without CMV disease +2 SD would discriminate only 9 of the 27 CMV episodes. Conclusions: Although the viral load is increased during episodes of clinic al CMV disease in lung transplant recipients, the quantitative PCR assessme nt of CMV DNA in BAL fluid is not discriminative enough to be useful as a d iagnostic tool for CMV disease.