Airway compression following thymus hyperplasia in an infant with Pierre Robin sequence and congenital diaphragmatic hernia.

A female infant with respiratory embarrassment due to external compression of the tracheobronchial tree by the thymus is presented. After successful intrauterine drainage of pleural effusions, she was born with a diaphragmatic hernia and Pierre Robin sequence, which required long-term mechanical ventilation and several surgical interventions, including tracheostomy, until she breathed spontaneously. At age 7 months, she was rehospitalized in respiratory failure because of pneumonia. At this time, thymus hyperplasia was first diagnosed, which had caused tracheobronchomalacia and displacement of the tracheobronchial tree. Weaning from the ventilator was unsuccessful for 8 weeks. She underwent thymectomy, following which impairment of breathing resolved immediately. Different manifestations of thymus enlargement and their relation to impaired breathing are discussed.