Risk factors for mortality after respiratory syncytial virus lower respiratory tract infection in adults with hematologic malignancies

Background: Respiratory syncytial virus (RSV) lower respiratory tract infection (LRTI) is associated with high mortality in patients with hematologic malignancies (HM). We sought to determine whether allogeneic hematopoietic cell transplant (allo-HCT) recipients would be at higher risk for 60-day mortality. Methods: We examined a retrospective cohort of adults with HM with or without HCT treated for RSV LRTI (n = 154) at our institution from 1996-2013. We defined possible RSV LRTI as RSV detected only in the upper respiratory tract with new radiologic infiltrates and proven RSV LRTI as RSV detected in BAL fluid with new radiologic infiltrates. Immunodeficiency Scoring Index (ISI) and Severe Immunodeficiency (SID) criteria were calculated for HCT recipients. Multivariable logistic regression analyses were performed to identify independent risk factors associated with 60-day all-cause mortality. Results: Mortality was high in HM patients (25%), but there was no difference between those without HCT, autologous or allo-HCT recipients in logistic regression models. Separate multivariate models showed that at RSV diagnosis, neutropenia (OR 8.3, 95% CI 2.8-24.2, P = 0.005) and lymphopenia (OR 3.7, 95% CI 1.7-8.2, P = 0.001) were associated with 60-day mortality. Proven LRTI was associated with higher 60-day mortality (neutropenia model: OR 4.7, 95% CI 1.7-13.5; lymphopenia model: OR 3.3, 95% CI 1.2-8.8), and higher ICU admission. In HCT recipients, high ISI and very severe immuno-deficiency by SID criteria were associated with higher 60-day all-cause mortality. Conclusions: Mortality is similarly high among HM patients without HCT and HCT recipients. High-grade immunodeficiency and detection of RSV from BAL fluid are associated with higher 60-day mortality.