Teaching Case

Short history of recurrent pulmonary infections, progressive dyspnea and cough. No asthma, allergy or tuberculosis in the past. Smoked 25 cigarettes per day for several years.

The patient, with a short history of recurrent pulmonary infections, progressive dyspnea and cough was admitted to the hospital. No asthma, allergy or tuberculosis in the past was reported, but she had smoked 25 cigarettes per day for several years. On physical examination no abnormalities were found. Laboratory tests revealed a slightly increased sedimentation rate and a normal white blood cell count. Further investigation included chest radiograph, CT scan of the chest, and digital subtraction angiography (DSA).

Pulmonary sequestration is a congenital pulmonary malformation in which a portion of nonfunctioning bronchopulmonary tissue is separated from the rest of the lung parenchyma. It always has an anomalous blood supply arising from the systemic arterial circulation. The anomaly may be intralobar or extralobar. A pulmonary sequestration is intralobar when its pleural envelope is in continuity with that of the rest of the lung. This type of sequestration is usually located above the diaphragm, in the posterior segment of the left lobe. In exceptional cases it can be found in the anterior segment of the right upper lobe. The anomaly is seldom bilateral. Radiologically, it manifests as single or multiple air-filled cavities or partially filled cystic lesions at the base of the lung. It is usually discovered on a routine chest radiograph, or when complications occur such as infection or hemoptysis. Sequestration, regardless of the type, almost invariably derives its arterial supply from the systemic circulation, most often from lower thoracic and upper abdominal aorta, or its branches. The diagnosis is confirmed by demonstrating an abnormal artery arising from the aorta or its branches, supplying the involved segment. The venous return is pulmonary in intralobar sequestrations.