Diffuse Alveolar Hemorrhage: An Unusual Presentation of Recurrent Malignant Melanoma.

Diffuse alveolar hemorrhage (DAH) is a syndrome characterized by bleeding into the alveolar spaces of the lungs, secondary to disruption of the alveolar-capillary basement membrane. While numerous disease processes have been associated with DAH including certain malignancies, to the best of our knowledge, recurrent malignant melanoma has not been previously described in the literature as a cause of DAH. Here, we present a case of a 73-year-old female with a history of malignant melanoma of the left shoulder status post wide local incision two years prior, who presented with complaints of progressive shortness of breath without productive cough or hemoptysis. On examination, she was hypoxemic and required high-flow nasal cannula initiation. Initial investigation revealed a hemoglobin of 4.6 g/dL. Computed tomography of the chest with contrast revealed multiple areas of rounded infiltrates with air bronchograms, mediastinal adenopathy, and a right pleural effusion. Diagnostic bronchoscopy revealed findings of recent bleeding throughout the tracheobronchial tree with progressively bloody bronchoalveolar lavage (BAL) suggestive of DAH. BAL cytology was positive for malignant melanoma. After a comprehensive workup that excluded the common causes of DAH, we present the first case of DAH caused by recurrent malignant melanoma.