“…9 However, any large vessel may be affected, including the PA. Involvement of the PA may lead to the development of pulmonary nodules, pleural effusions, aneurysms, thromboses, perfusion defects and pulmonary hypertension, and presents with nonspecific chest pain, dyspnea, cough, or hemoptysis secondary to pulmonary hemorrhage. [10][11][12][13] Although not common, isolated PA involvement has been reported. 10,12 Consistent with this patient's presentation, pleural effusions have been described as the initial presentation of TA given the close proximity of the left PA to the parietal pleura.…”