A Bloody Cough and Clouded Lungs: Uncovering a Systemic Culprit in an Adolescent.

Hemoptysis secondary to diffuse alveolar hemorrhage (DAH) is uncommon in children. When it does occur, extensive investigations are often required to determine the underlying cause. We present a unique case of a 17-year-old previously healthy male adolescent with a history of allergic rhinitis, who initially presented with pneumonia in the setting of influenza A. He subsequently developed DAH, prompting further diagnostic evaluations that ultimately revealed a rare condition with long-term morbidity.