Decreasing mortality rate in early pneumonia following hematopoietic stem cell transplantation

Pulmonary complications after allogeneic hematopoietic stem-cell transplantation (HSCT) remain 1 of the most important causes of morbidity and mortality. This study evaluates the change over time of incidence, aetiology and risk factors for death related to pneumonia within 3 months after HSCT. 997 patients who underwent HSCT were studied retrospectively. Most patients (83%) had a haematological malignancy. The majority (89%) had an HLA-A, -B, and -DR matched related or unrelated donor. Conditioning consisted of cyclophosphamide and total-body irradiation or busulfan and graft-versus-host disease prophylaxis of cyclosporin and methotrexate in most cases. Death related to pneumonia occurred in 56 (5.6%) patients. Cytomegalovirus (37%) was the main pathogen involved, especially during the first 2 decades studied. In the multivariate risk factor analysis, we found that death from pneumonia was significantly associated with receiving a T-cell depleted graft (p<0.001), bacteraemia (p=0.001), and y of transplantation (p<0.001). In patients receiving a transplant during the last decade, the incidence of death related to pneumonia was 2.8% compared to 8.9% during the first decade. We conclude that the rate of mortality related to pneumonia has decreased over time, possibly as a result of improved diagnostic, prophylactic and therapeutic methods and treatment.