Clinical outcomes and prognostic factors in hematologic malignancy patients with probable CMV pneumonia

Cytomegalovirus (CMV) infection is an important cause of morbidity and mortality among immunocompromised patients, particularly those with hematologic malignancies. The present study aims to evaluate the clinical features, laboratory parameters, and treatment characteristics associated with 30-day and 90-day mortality in patients with hematologic malignancies diagnosed with probable CMV pneumonia.

We conducted a retrospective cohort study including 61 patients with hematologic malignancies who were diagnosed with probable CMV pneumonia between January 2018 and October 2023. Demographic data, underlying disease characteristics, laboratory parameters, CMV DNA levels in blood and bronchoalveolar lavage fluid, co-infections, and antiviral treatment features were recorded. The primary outcomes were all-cause mortality at 30 and 90 days. Factors associated with mortality were evaluated using univariate analyses and multivariate time-dependent Cox proportional hazards regression models to account for potential immortal-time bias related to antiviral treatment duration.

The median age was 57 (19-84) years, and 65.6% of patients were male. All-cause mortality was 29.5% at 30 days and 62.2% at 90 days. In the time-dependent Cox regression analysis, longer antiviral therapy duration was significantly associated with lower 30-day mortality, with each additional treatment day reducing the risk by approximately 8.3% (HR 0.917; 95% CI 0.866-0.971; p = 0.003). A similar protective trend was observed for 90-day mortality, although the association did not reach statistical significance (HR 0.957; 95% CI 0.912-1.004; p = 0.074). Higher serum urea levels were independently associated with increased 30-day mortality, whereas no significant association was observed with 90-day mortality. Baseline CMV DNA levels and longitudinal viral load changes during treatment were not significantly associated with mortality.

Patients with hematologic malignancies and probable CMV pneumonia experience high early and mid-term mortality. A longer antiviral treatment duration was associated with improved short-term survival, even after adjustment for immortal-time bias, whereas baseline virologic burden was not associated with mortality. These findings suggest that treatment feasibility and host-related factors may have a greater prognostic impact than initial CMV viral load in this patient population.