Arterial tortuosity syndrome (ATS) is a rare connective tissue disorder characterized by tortuosity and elongation of the large and medium-sized arteries and a propensity towards aneurysm formation, vascular dissection, and stenosis of the pulmonary arteries.
Prevalence is unknown but less than 80 cases have been described in the literature so far. The male to female ratio is 1:1.
The clinical manifestations are variable, depending on the arteries affected. Onset usually occurs in infancy or early childhood. The cardiovascular anomalies may lead to right ventricular hypertension, acute respiratory symptoms, ventricular hypertrophy and cardiac failure. Patients are prone to aneurysm formation, dissection and ischemic events. Other typical manifestations are dysmorphic features (including an elongated face, micrognathia, a high palate, and a beaked nose), soft and hyperextensible skin, cutis laxa (see this term), hernias (inguinal, diaphragmatic, or hiatal), skeletal abnormalities, joint hypermobility, congenital contractures, keratoconus and generalized hypotonia.
ATS is caused by mutations in the SLC2A10 gene (20q13.12), encoding the facilitative glucose transporter 10 (GLUT10). So far, 18 SLC2A10 mutations have been reported in 34 families. The role of GLUT10 in the pathogenesis of the disorder is still unknown, but loss-of-function SLC2A10 mutations are likely to influence proteoglycan biosynthesis ultimately leading to disarray of the connective tissue extracellular matrix.
Diagnosis requires further examination by echocardiography (ECG), angiography, and magnetic resonance angiography (MRA) and/or CT scan. Histology shows disruption of elastic fibers of the medial layer of the arterial wall. Detection of mutations in the SLC2A10 gene allows confirmation of the clinical diagnosis, and allows adapted genetic counseling and prognostic information to be provided to the patients.
The differential diagnosis should include Loeys-Dietz syndrome, the vascular type of Ehlers-Danlos syndrome (EDS IV) and Marfan syndrome (see these terms).
Prenatal diagnosis may be suspected by echocardiography and ultrasonography, and can be confirmed by prenatal molecular diagnosis performed on chorionic villi or amniocytes. Pregnancy in ATS requires intensive monitoring of both mother and fetus, cesarean delivery, and multidisciplinary postpartum care.
ATS is transmitted in an autosomal recessive manner.
All ATS patients require regular follow-up (periodic EGC, and MRA and/or CT scan) and may benefit from surgical interventions (aortic root replacement for aortic aneurysms and pulmonary artery reconstruction).
The prognosis can be severe (with a mortality rate of up to 12%, usually before the age of 5 years) with respiratory insufficiency, ventricular hypertrophy resulting in global heart failure, myocarditis, and ischemic events leading to organ infarction being the main causes of premature death.
Last update: November 2009