Bronchopulmonary sequestration: an unusual presentation.

We have described a case of extralobar sequestration involving the left upper lobe in a 4-year-old boy. The etiology of this anomaly remains obscure, but it may result from a supranumerary lung bud arising from the pharynx. Unlike intralobar sequestrations, extralobar sequestrations frequently have associated anomalies. Clinically the symptoms are variable. Our patient was cured by surgical excision of the lesion.