Distribution characteristics and influencing factors of active cytomegalovirus infection in patients with hematological malignancies complicated with sepsis

Background Cytomegalovirus (CMV) tends to reactivate in immunocompromised individuals. Patients with hematological malignancies are at high risk of CMV infection due to treatment-related immunosuppression, and sepsis may further promote latent CMV reactivation via inflammatory disorders. However, research on active CMV infection in patients with both conditions remains limited; Methods: A single-center retrospective cohort study included 119 patients with hematological malignancies complicated by sepsis (Ningbo Medical Center Lihuili Hospital, June 2022–June 2025). Patients were divided into active CMV infection group (plasma CMV DNAemia ≥ 500 copies/mL, 41 cases) and non-active group (< 500 copies/mL, 78 cases) via qPCR. Clinical features, laboratory indicators, treatment, and outcomes were compared; regression analysis screened risk factors, and ROC curves assessed predictive value of indicators; Results: Active CMV infection incidence was 34.45%, with 92.68% occurring within 0–7 days of hospitalization. CMV was detected in lower respiratory tract specimens of 21.84% patients, and plasma CMV load correlated positively with that in these specimens (r = 0.558, P  < 0.001). The active group had lower weight, BMI, hemoglobin, albumin, white blood cell and platelet counts, but higher SOFA scores and body temperature (all P  < 0.05). The active group had higher rates of blood transfusion and immunosuppressant use, longer hospitalization and fever duration, and higher 28-day all-cause mortality (all P  < 0.05); no difference in complication incidence was observed. Decreased white blood cell count was an independent risk factor (β=-0.209, OR = 0.811, P  = 0.021) with optimal predictive value (AUC = 0.746); hemoglobin and platelet count also had good predictive value; Conclusions: Patients with hematological malignancies complicated by sepsis have high active CMV infection incidence (mostly early hospitalization), associated with poor prognosis. Decreased white blood cell count is a useful early screening indicator, requiring early clinical monitoring and intervention.