Rasmussen's Aneurysm: A Rare but Life-Threatening Complication of Pulmonary Tuberculosis - A Case Report

Rasmussen's aneurysm is a rare but potentially fatal complication of pulmonary tuberculosis. It represents a pseudoaneurysm of a pulmonary arterial branch caused by erosion of the arterial wall secondary to chronic inflammation within a tuberculosis cavity. Although uncommon, especially in non-endemic regions, rupture of this aneurysm can result in massive hemoptysis and carries a high mortality if not promptly recognized and managed. We report a case of a healthcare worker in the United States, a non-endemic region, who presented with massive, life-threatening hemoptysis. She was found to have active pulmonary tuberculosis. Computed tomography angiography demonstrated a 10-mm pseudoaneurysm arising from the apical branch of the left pulmonary artery protruding into a cavitary lesion in the left upper lobe. Four months prior to presentation, she had been diagnosed with latent tuberculosis but had declined treatment. The patient was started on anti-tuberculosis therapy after presenting with hemoptysis. Endovascular embolization of the left upper-lobe subsegmental pulmonary artery was successfully performed, resulting in complete resolution of hemoptysis. Rasmussen's aneurysm, though rare, can occur outside endemic regions and may follow a rapid progression from latent to active tuberculosis. Awareness, early imaging, and prompt endovascular intervention are crucial to reduce morbidity and mortality. Screening and treatment of latent tuberculosis remain essential to prevent progression to active disease and such severe complications.