Diffuse alveolar hemorrhage and infection-associated alveolar hemorrhage following hematopoietic stem cell transplantation: related and high-risk clinical syndromes.

Diffuse alveolar hemorrhage (DAH) is a noninfectious pulmonary complication of hematopoietic stem cell transplantation (HSCT) with unclear pathogenesis and treatment. We reviewed prospectively collected data on 1919 consecutive transplants performed between 1995 and 2004 and compared patients with DAH and infection-associated alveolar hemorrhage (IAH) who presented with similar symptoms of hypoxemia, pulmonary infiltrates, and progressively bloody alveolar lavage but also had microorganisms isolated from blood, bronchoalveolar lavage, or tracheal aspirate within 1 week of alveolar hemorrhage. Overall, 116 patients had alveolar hemorrhage (45 with DAH, 71 with IAH). Older age, allogeneic donor source, myeloablative conditioning regimen, and acute severe graft-versus-host disease (GVHD) were independently predictive of an increased risk of post-HSCT alveolar hemorrhage. The DAH and IAH groups were comparable except for a higher proportion of patients receiving umbilical cord blood as a donor source and total-body irradiation-containing conditioning in the IAH group. The probability of 60-day survival from onset of hemorrhage was 16% (95% CI, 6%-26%) for the DAH and 32% (95% CI, 21%-43%) for the IAH group (P = .08). All except 20 patients were treated with a standard regimen of high-dose corticosteroids. Patients who received corticosteroids had 60-day survival of 26% (95% CI, 18%-34%), compared with 25% (95% CI, 6%-44%) for those who did not (P = .28). The pathogenesis of alveolar hemorrhage after HSCT is multifactorial, and we propose that IAH and DAH in HSCT recipients are related clinical syndromes with similar clinical presentation, risks, and associated high mortality.