Diffuse alveolar hemorrhage due to Legionella pneumophila serogroup 3

Legionella pneumophilia remains an important cause of pneumonia that can cause substantial clinical morbidity and mortality. We describe a case involving a 67-year-old woman with legionella pneumonia who developed diffuse alveolar hemorrhage. We also highlight the pitfalls of commonly used legionella urine antigen testing. Furthermore, we explore the role of high-dose steroid therapy as a treatment option for patients with diffuse alveolar hemorrhage secondary to legionella pneumonia who continue to deteriorate in spite of adequate antimicrobial therapy.