Isolated major aortopulmonary collateral artery in an infant presenting with recurrent lower respiratory tract infection.

A 5-month-old baby, weighing 4 kg presented with a 3-month history of failure to thrive and recurrent lower respiratory tract infection (RTI). She was delivered at term weighing 2.8 kg and the perinatal period was uneventful. Saturation and clinical examination was normal and there were no abnormal auscultation findings or murmur. Chest x-ray had normal cardiac and pulmonary contours while previous x-rays had evidence of lower RTI involving the right lung. An echocardiogram showed no evidence of congenital heart disease (CHD) with no shunts and there was no evidence of left ventricular volume overload …