Scimitar syndrome with horseshoe kidney and portal vein thrombosis: A case report

Clinical History

A 17-year-old male patient presented with 2-year history of right chest pain and mild shortness of breath. On clinical examination there were decreased breath sounds on right side of chest.

Imaging Findings

Chest radiograph revealed small right hemithorax with elevated dome of right hemidiaphragm. Contrast enhanced CT examination demonstrated small right hemithorax with hypoplastic right lung and elevated right hemidiaphragm (Figure 1). The right lung was drained by an aberrant vein draining into the inferior vena cava (Figure 2). The right lung was supplied by an anomalous artery arising from abdominal aorta at the level of renal hilum with absent normal right pulmonary artery (Figure 3, 4). Multiple vertebral anomalies were disclosed (Figure 5). Aberrant right subclavian artery was also seen passing posterior to the oesophagus (Figure 6). Abdominal CT revealed horseshoe kidney (Figure 7) and hypoplastic right lobe of liver with thrombus in right branch of portal vein (Figure 8, 9), which are unusual associated anomalies. Subsequent echocardiography was performed in order to investigate any associated cardiac anomalies but it was unremarkable.

Discussion

Scimitar syndrome or pulmonary venolobar syndrome is a syndrome of unknown aetiology [1]. The first reported case of Scimitar syndrome was published in 1836 by Cooper [2]. The most constant and defining components of scimitar syndrome are hypogenetic lung and partial anomalous pulmonary venous return [3]. The name comes from this anomalous pulmonary vein which may be visible on chest radiograph in 1/3 of cases as a curvilinear shadow just above the right hemidiaphragm said to resemble a "scimitar" or Persian sword, “shimshir” [4].
It is also characterised by other major components of absent pulmonary artery, systemic arterialisation of lung, pulmonary sequestration, absent/interrupted inferior vena cava and duplication of diaphragm and minor components include tracheal trifurcation, eventration of diaphragm, partial absence of diaphragm, phrenic cyst, horse shoe lung, oeseophageal/gastric lung, anomalous superior vena cava and absent left pericardium. Other associated anomalies are hemivertebra, scoliosis and congenital heart diseases including septal defects, PDA, tetralogy of fallot and hypoplastic left heart [1].
The age of presentation can be between neonatal period and adulthood. Prognosis of the disease depends on age of presentation and associated anomalies. Based on age of presentation two forms of scimitar syndrome are identified: infantile form presenting within 1 year of life with rapidly progressing congestive heart failure and adult form diagnosed after 1 year of age and presents with mild symptoms or remains asymptomatic for life. The infantile form has poor prognosis and needs early surgical repair while adult form has better prognosis even without surgical correction [5]. Diagnosis is suggested by radiographic findings of hypoplastic right hemithorax and scimitar shaped curvilinear vein along right cardiac border. Traditionally angiography has been the modality of choice to demonstrate vascular anomalies but now multislice helical CT with multiplanar reconstruction allows delineation of complex anomalies seen in pulmonary venolobar syndrome [6]. Echocardiography is recommended for detecting associated cardiac anomalies. Meandering pulmonary vein, dextrocardia, hypoplastic lung and swyer james syndrome should be considered in differential of scimitar syndrome.
Our patient presented at age 17 with 2 years history of shortness of breath and right chest pain, demonstrating hypoplastic right lobe of liver with thrombus in the right branch of the portal vein on contrast enhanced CT, which are unusual associated anomalies in scimitar syndrome.

Differential Diagnosis List

Final Diagnosis

Scimitar syndrome with horseshoe kidney and portal vein thrombosis.

URL:	https://www.eurorad.org/case/10143
DOI:	10.1594/EURORAD/CASE.10143
ISSN:	1563-4086