Asymptomatic Unilateral Pulmonary Hypoplasia/Agenesis in Adults: A Report of Six Cases

Bilateral pulmonary agenesis is incompatible with extrauterine life. Unilateral pulmonary hypoplasia or agenesis is rare, the vast majority of cases presenting in the newborn, infancy, or early childhood, with respiratory symptoms. Pulmonary hypoplasia or agenesis presenting in adults is extremely rare, and the initial chest radiographs may present significant interpretation challenges. We report six patients encountered incidentally in a 10-year period, during which approximately 400,000 routine adult chest radiographs were reported. In all six cases, the chest X-ray films were equivocal, and multidetector computed tomography (CT) was required to settle the diagnosis. The cases are presented to draw the attention of radiologists and physicians to this rarity and to avert the kind of initial errors that we made in interpreting their chest radiographs. The invaluable role of multidetector CT in resolving this potential confusion is emphasized. A brief review of the relevant literature is undertaken.