Misplaced pulmonary arteries in an adult patient with pulmonary hypertension.

Misalignment of pulmonary vessels, with or without alveolar capillary dysplasia, is a rare cause of persistent pulmonary hypertension in the newborn. The prognosis is poor, with virtually all patients succumbing to unremitting hypoxaemic respiratory failure and death during the newborn period. We report the CT and histological findings of misplaced pulmonary arteries in a previously healthy young adult patient who presented with pulmonary arterial hypertension. Contiguous high-resolution spiral CT angiography showed small pulmonary arteries coursing within the interlobular septa and enlarged central pulmonary arteries. Surgical lung biopsy demonstrated anomalous muscularised pulmonary arteries in the interlobular septa. This is, to our knowledge, the first report of misplaced pulmonary arteries presenting in an adult patient and may represent a forme fruste of the neonatal vascular anomaly. A possible association with pulmonary arterial hypertension is also suggested in this case.