Extralobar pulmonary sequestration. Unusual presentation and systemic vascular communication in association with a right-sided diaphragmatic hernia.

A 17-day-old infant with a right-sided extralobar pulmonary sequestration associated with an intact diaphragmatic hernia sac presented as an acute respiratory emergency. The diagnosis was obscured by the initial resuscitative treatment of cardiorespiratory arrest necessitating positive-pressure ventilation complicated by bilateral tension pneumothoraces prior to transfer. At operation, unique systemic arterial and venous communications to the sequestration from the dome of the liver through the intact hernia sac were found. A bronchial communication to the right main bronchus was also present. Histologic examination of the sequestration specimen revealed other features common to both intralobar and extralobar sequestration. This case lends support to the hypothesis of a common embryologic basis for both types of sequestration, as well as other congenital pulmonary cystic abnormalities, and the association with diaphragmatic hernia.