Congenital agenesis of the right pulmonary artery in an 18-year-old female presenting with hemoptysis and shortness of breath: a case report

Unilateral absence of a pulmonary artery (UAPA), also termed unilateral pulmonary artery agenesis, is a rare congenital vascular anomaly. When it occurs in isolation it involves the right pulmonary artery in about two-thirds of cases, whereas left-sided absence is more often associated with congenital heart disease. Presentation ranges from an incidental imaging finding to hemoptysis, exertional dyspnea, recurrent infection and pulmonary hypertension. We report the case of an 18-year-old female with no prior medical history who presented with shortness of breath and hemoptysis of one-month duration. The hemoptysis was scant, consisting of blood-streaked sputum, with approximately 5–10 mL of blood expectorated over 24 h. CT pulmonary angiography showed agenesis of the right pulmonary artery with systemic supply to the right hilum through hypertrophied bronchial arteries, a hypoplastic right lung with ipsilateral parenchymal changes, and compensatory hyperinflation of the left lung. Transthoracic echocardiography showed no structural heart disease and a low echocardiographic probability of pulmonary hypertension. She was managed conservatively with bed rest, oral tranexamic acid and cough suppression and had no further episodes of hemoptysis over six months of follow-up. Congenital agenesis of the right pulmonary artery should be considered in young patients with unexplained hemoptysis, particularly in tuberculosis-endemic settings where a small, abnormal lung is easily attributed to previous infection. CT pulmonary angiography can establish the diagnosis and help distinguish it from conditions that mimic it. Echocardiographic screening for pulmonary hypertension and a defined follow-up plan should accompany the diagnosis.