[Pulmonary sequestration and enteric cyst, 2 expressions of the same abnormality].

We report the case of an 18-month-old boy operated on for a right lower lobe bronchopulmonary sequestration. At the immediate postoperative check-up, a septic right thoracic effusion appeared, connected to a cystic mediastinal retrocrural formation on CT. After a drainage attempt and medical therapy, the abdominal lesion was resected. Histological examination showed that the cyst cavity was lined with pseudostratified non-ciliated epithelium, without cartilage, consistent with an enteric cyst. Regardless of the embryological theory, a literature review confirmed that in presence of one of these two lesions, one should systematically look for the other.