Abstract
Diffuse alveolar hemorrhage (DAH) can result from autoimmune disorders, drugs, toxins, and rarely infections. Autoimmune & infection-mediated DAH have different pathophysiology and thus contrasting management. Autoimmune-DAH results from capillaritis and is treated with immunosuppressives, occasionally combined with plasmapheresis. Conversely, infection-related DAH results from cytotoxin-mediated diffuse alveolar damage and is treated with antibiotics. DAH caused by Mycoplasma pneumoniae (MP) is exceptionally rare. This report describes a fatal case of MP infection-related DAH and highlights its management challenges.
A 64-year-old male with heart failure with preserved ejection fraction (HFpEF), chronic obstructive pulmonary disease (COPD), presented with acute on chronic hypoxic and hypercapnic respiratory failure requiring intubation. Empiric broad-spectrum antibiotics, including atypical coverage with azithromycin, were initiated. Chest imaging showed diffuse bilateral infiltrate. Bronchoscopy showed bloody aspirate; sequential BAL became progressively hemorrhagic. He received high-dose methylprednisone for DAH. Autoimmune work-up was negative; infectious work-up was positive only for Mycoplasma IgM. Despite a lung-protective ventilator strategy and other supportive measures, his clinical condition deteriorated. His spouse declined ECMO, respecting his prior expressed wish. He died 7days after hospitalization despite appropriate supportive care.
Antibiotic resistance may be a concern if infection-related DAH does not improve with antibiotic therapy. Macrolide-resistant MP (MRMP) is prevalent in eastern Asia, but rare in the US. The role of steroids in infection-related DAH is extrapolated from pneumonia trials. ARDS-net ventilation protocols are recommended for DAH, given similar pathophysiology. Although ECMO with systemic anticoagulation may exacerbate alveolar bleeding, the potential of ECMO with regional anticoagulation warrants further investigation.
•Consider infection in DAH, even when autoimmune causes seem likely.•Mycoplasma pneumoniae can rarely cause fatal DAH in adults.•Sequential BAL with progressive bloody return confirms DAH.•Differentiate autoimmune from infection-related DAH, as treatment differs.•Steroids, plasmapheresis, and ECMO have uncertain roles in infectious DAH.