Journal of Dr. NTR University of Health Sciences

CASE REPORT
Year
: 2017  |  Volume : 6  |  Issue : 1  |  Page : 52--54

Extralobar pulmonary sequestration in adults


Ravikanth Reddy 
 Post-graduate Student in Radiology, St. John's Medical College, Bengaluru, Karnataka, India

Correspondence Address:
Ravikanth Reddy
Post-graduate Student in Radiology, St. John's Medical College, Bengaluru - 560 034, Karnataka
India

Abstract

Pulmonary sequestration is defined as a nonfunctioning mass composed of dysplastic lung parenchyma, embryologically detached from the tracheobronchial tree and receiving its own blood supply from a systemic artery, usually the thoracic or abdominal aorta. It may be intralobar or extralobar depending on the presence of an independent pleural envelope. Extralobar sequestration is a much rarer entity, and diagnosis is usually made antenatally or in early life. Here, we present a rare case of extralobar pulmonary sequestration in an adult.



How to cite this article:
Reddy R. Extralobar pulmonary sequestration in adults.J NTR Univ Health Sci 2017;6:52-54


How to cite this URL:
Reddy R. Extralobar pulmonary sequestration in adults. J NTR Univ Health Sci [serial online] 2017 [cited 2019 Jul 22 ];6:52-54
Available from: http://www.jdrntruhs.org/text.asp?2017/6/1/52/202578


Full Text



 Introduction



Pulmonary sequestration is an uncommon congenital anomaly of the primitive foregut. Extralobar pulmonary sequestration is rare and often found between the lower lobe and diaphragm. The sequestered segment of the lung is completely separated and enclosed in its own pleural investment. The definite diagnosis of pulmonary sequestration depends on the demonstration of the systemic arterial supply and venous drainage. Here, we present a rare case of extralobar pulmonary sequestration in an adult.

 Case Report



A 32-year-old woman presented to the emergency department with a 2-month history of left thoracic pain, cough, anorexia, and weight loss. Preoperative chest X-ray done showed a wedge-shaped opacity in the left lower zone causing obliteration of the left costophrenic angle and loss of clarity of the adjacent hemidiaphragm [Figure 1]. Multidetector contrast-enhanced computed tomography (CECT) of the thorax was performed, which revealed a wedge-shaped heterogeneously enhancing soft tissue attenuation mass [Figure 2] and [Figure 3], measuring 6.0 × 3.0 × 5.5 cm (AP × ML × CC) with a central nonenhancing hypodense area. The lesion was noted to derive arterial supply from the thoracic aorta at the level of D9 vertebra. Imaging did not reveal any evidence of air bronchograms communication with the tracheobronchial tree or left pleural effusion. In addition, CECT of the abdomen and pelvis was done to screen for associated congenital anomalies, and a gastric duplication cyst measuring 6 × 5 cm was visualized [Figure 4]. The patient underwent surgery for the extralobar lung sequestration, and a hard mass located above the left hemidiaphragm was resected. A 1-cm diameter arterial vessel supplied the lesion, and venous drainage via the pulmonary veins to the left atrium was confirmed. Pathological examination revealed a mass composed of dysplastic pulmonary tissue with an independent pleural envelope, thus confirming the diagnosis of pulmonary sequestration of the extralobar type. Postoperative chest X-ray done 2 weeks apart showed mild hypovascularity in the left lower lobe following resection of the extralobar pulmonary sequestration [Figure 5].{Figure 1}{Figure 2}{Figure 3}{Figure 4}{Figure 5}

 Discussion



Pulmonary sequestration is a nonfunctioning lung tissue that is not in normal continuity with the tracheobronchial tree deriving its blood supply from systemic circulation. It constitutes 0.15–6.4% of all congenital pulmonary malformations.[1] Extralobar pulmonary sequestration occurs more frequently in males than females with a male-to-female ratio of 4:1.[2] Extralobar sequestration is the result of an anomalous or supernumerary lung bud that derives its blood supply from the primitive splanchnic vessels that surround the foregut. The anomalous arterial supply of the sequestration is usually from the dorsal aorta.[3] Clinical manifestations usually occur in the newborn period or early infancy with symptoms of respiratory distress, repeated infections, high output congestive heart failure, and spontaneous pulmonary or pleural hemorrhage. Treatment consists of complete surgical excision of the extralobar sequestration. Congenital anomalies occur more frequently in patients with extralobar sequestration than intralobar lung sequestration. Associated anomalies include congenital cystic adenomatoid malformation, congenital diaphragmatic hernia, vertebral anomalies, congenital heart disease, pulmonary hypoplasia, colonic duplication, tracheoesophageal fistula, bronchogenic cyst, pericardial defects, and congenital megacolon. Approximately 50–60% of the patients have associated malformations, the most common being congenital diaphragmatic hernia with the esophagus or stomach.[4] Type II cystic adenomatoid malformation of the lung has been reported in 15–25% of patients with extralobar sequestration. Our case demonstrated a gastric duplication cyst.

 Conclusion



In conclusion, the diagnosis of pulmonary sequestration relies on the demonstration of aberrant systemic arterial supply to a pulmonary or juxtapulmonary mass on imaging. Differential diagnosis of extralobar pulmonary sequestration is consolidation, intrathoracic kidney, and hepatic herniation through the diaphragm. Complete surgical excision of the sequestrum is the treatment of choice to reduce the risk of repeated infections.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1Lin CH, Chuang CY, Hsia JY, Lee MC, Shai SE, Yang SS, et al. Pulmonary sequestration-differences in diagnosis and treatment in a single institution. J Chin Med Assoc 2013;76:385-9.
2Wei Y, Li F. Pulmonary sequestration: A retrospective analysis of 2625 cases in China. Eur J Cardiothorac Surg 2011;40:e39-42.
3Andrade CF, Ferreira HP, Fischer GB. Congenital lung malformations. J Bras Pneumol 2011;37:259-71.
4Sulhyan KR, Ramteerthakar NA, Gosavi AV, Anvikar AR. Extralobar sequestration of lung associated with congenital diaphragmatic hernia and malrotation of gut. Lung India 2015;32:381-3.