Diagnosis of Intra-Abdominal Extralobar Pulmonary Sequestration by means of Ultrasound in a Neonate

Pulmonary sequestration is a congenital abnormality consisting of a mass of pulmonary tissue that presents an abnormal connection with the tracheobronchial tree, with a blood supply coming from an anomalous artery derived from the systemic circulation. Extralobar pulmonary sequestration is characterized by having pleural coverings that are independent of the normal lungs, with vascular supply usually coming from the aorta or from one of its branches. This diagnosis can be suspected prenatally if an abdominal mass, generally below the diaphragm, is seen. Here, we present a case of a neonate on the second day of life, with ultrasonography showing extralobar pulmonary sequestration located above the left adrenal gland that prenatally simulated a neuroblastoma. 1. Introduction Pulmonary sequestration is an uncommon congenital abnormality consisting of a mass of pulmonary tissue that presents an abnormal connection with the tracheobronchial tree, with a blood supply coming from an anomalous artery derived from the systemic circulation. This condition can be classified as extralobar or intralobar, according to its location in relation to the normal lung and its coverings of visceral pleura [1]. Intralobar pulmonary sequestration is characterized by sharing the same visceral pleural coverings that normal lungs have. It is most frequently located in the posterolateral segment of the left lower lobe. In 75% of the cases, its blood supply is derived from the aortic artery, while in the remainder of the cases the blood supply is derived from other thoracic or abdominal vessels. The venous drainage usually takes place through the pulmonary veins. In around 90% of the cases, it is presented as an isolated finding, without other echographic signs [2, 3]. Extralobar pulmonary sequestration is characterized by having pleural coverings that are independent of the normal lungs, with vascular supply usually coming from the aorta or from one of its branches. The venous drainage may take place through the azygos, hemiazygos, portal, or pulmonary vein system. The commonest location is the posterior part of the chest, and in 80 to 90% of the cases, it is on the left side. In up to 15% of the cases, it may be located below the diaphragm. In around 60% of the cases, it shows associations with other abnormalities such as congenital diaphragmatic hernia, hydrops, and vertebral and cardiac malformations [3]. Extralobar pulmonary sequestration is generally diagnosed prenatally from the second trimester onwards. On ultrasound, it is usually viewed as a small echodense solid mass