When the Unexpected Happens: Diffuse Alveolar Hemorrhage in Negative-Pressure Pulmonary Edema.

Negative-pressure pulmonary edema (NPPE) is an uncommon complication of acute airway obstruction, classically resulting in non-cardiogenic pulmonary edema. Diffuse alveolar hemorrhage (DAH) occurring in the setting of NPPE is exceedingly rare but can be life-threatening. We present the case of a young adult who developed NPPE complicated by DAH following a brief episode of acute upper airway obstruction. The patient exhibited sudden hemoptysis and respiratory failure, with imaging confirming pulmonary edema and new bilateral infiltrates consistent with hemorrhage. Bronchoscopic evaluation and laboratory workup excluded other causes of DAH. Supportive management, including airway protection, mechanical ventilation with positive end-expiratory pressure, and careful hemodynamic support, led to rapid clinical improvement. The patient made a full recovery with complete resolution of pulmonary infiltrates. This case underscores that even short-lived airway obstruction can precipitate DAH via NPPE, highlighting the importance of prompt recognition and management of this unexpected complication.