Diffuse Alveolar Hemorrhage in Acute Myeloid Leukemia.

Diffuse alveolar hemorrhage is a potentially fatal pulmonary disease syndrome that affects individuals with hematological and nonhematological malignancies. The range of inciting factors is wide for this syndrome and includes thrombocytopenia, underlying infection, coagulopathy, and the frequent use of anticoagulants, given the high incidence of venous thrombosis in this population. Dyspnea, fever, and cough are commonly presenting symptoms. However, clinical manifestations can be variable. Obvious bleeding (hemoptysis) is not always present and can pose a potential diagnostic challenge. Without prompt treatment, hypoxia that rapidly progresses to respiratory failure can occur. Diagnosis is primarily based on radiological and bronchoscopic findings. This syndrome is especially common in patients with hematological malignancies, given an even greater propensity for thrombocytopenia as a result of bone marrow suppression as well as the often prolonged immunosuppression in this patient population. The syndrome also has an increased incidence in individuals with hematological malignancies who have received a bone marrow transplant. We present a case series of 5 patients with acute myeloid leukemia presenting with diffuse alveolar hemorrhage at our institution. A comparison of clinical manifestations, radiographic findings, treatment course, and outcomes are described. A review of the literature and general overview of the diagnostic evaluation, differential diagnoses, pathophysiology, and treatment of this syndrome are discussed.