Unilateral primary pulmonary agenesis and hypoplasia in monozygotic twins

Abstract

We describe 10-month-old identical female twin infants, one with primary left-sided pulmonary agenesis and the other with primary left-sided pulmonary hypoplasia. They came to our outpatient clinic complaining of persistent dry cough. The clinical examination revealed decreased air entry over the left hemithorax. Chest x-rays showed complete left-sided radio-opacity in both the twins. The chest computed tomography scan with contrast confirmed the diagnoses of left-sided pulmonary agenesis (twin A) and left-sided hypoplasia (twin B). No other associated congenital anomaly was noted in either of the twins. To our knowledge, such a condition in live monozygotic twins has not been previously reported in published studies.

Figure 1

Selected images of contrast enhanced computed tomography (CECT) scan of the chest with Twin A demonstrating a completely absent left lung, left main pulmonary artery and left main bronchus. Large right main pulmonary artery (*), right bronchial branches (tiny white arrows), organized sequestrated lung tissue (black arrow), with arterial blood supply from ascending aorta (long white arrows). Twin B CECT scan of the chest demonstrates hypoplasia of left lung (black dotted arrows), tracheal bifurcation (black arrows), large right main pulmonary artery (*). Absent left main pulmonary artery.