Late-onset severe pneumonia after allogeneic hematopoietic stem cell transplantation: prognostic factors and treatments

Background In this study, we aimed to evaluate the prognostic factors associated with and treatments for late‐onset severe pneumonia (LOSP) in patients who underwent allogeneic hematopoietic stem cell transplantation (allo‐HSCT). Methods Fifty consecutive patients who underwent non‐T‐cell‐depleted allo‐HSCT at the Peking University Institute of Hematology and met the criterion of LOSP after allo‐HSCT were enrolled. Results The median time from allo‐HSCT to the occurrence of LOSP was 231 (90–1487) days. Twenty‐eight patients harbored 1 or more pathogens (infectious LOSP, I‐LOSP), whereas 22 did not harbor any pathogens (non‐infectious LOSP, NI‐LOSP). The 100‐day survival rate of LOSP patients was 31.1%. Patients smoking before allo‐HSCT (0% vs. 35.4%, P = 0.002) and male gender (20.0% vs. 61.9%, P = 0.026) had lower 100‐day survival rate. Patients with a lower bronchoalveolar lavage fluid (BALF) neutrophil percentage had higher 100‐day survival rate relative to those with higher BALF neutrophil percentage (45.5% vs. 16.7%, P = 0.012). The 100‐day survival rate of patients with I‐LOSP was lower than that of patients with NI‐LOSP (19.1% vs. 46.9%, P = 0.043). Patients given late (≥1 week after LOSP diagnosis) and low‐dose methylprednisolone (MP) therapy (≤2 mg/kg/day) had the best 100‐day survival rate. In the multivariate analysis, nonsmoking before allo‐HSCT and late and low‐dose MP therapy were significantly associated with a better survival after LOSP. Conclusion LOSP is a severe complication after allo‐HSCT. The correct timing and corticosteroid dosage in the context of broad‐spectrum antimicrobial therapy might further improve the outcomes of patients with LOSP.