Hemoptysis is a common presenting symptom of hereditary hemorrhagic telangiectasia (HHT), an often overlooked diagnosis in the emergency setting. Patient history often includes telangiectasias, epistaxis, visceral lesions, and a family history of similar findings. Here, we review a case of HHT in a young woman, presenting initially with hemoptysis. Imaging was significant for large left upper lobe arteriovenous malformation (AVM), requiring patient admission and interventional radiology embolization of the AVM. The purpose of this report is to highlight a diagnosis that is important not to miss in the emergency department.TopicsPulmonary arteriovenous malformation, hereditary hemorrhagic telangiectasia, Osler-Weber-Rendu syndrome.