[Loeys-Dietz syndrome (TGFßR2 mutation) in a 4-year-old child with thoracic aortic aneurysm]. / Syndrome de Loeys-Dietz (mutation TGFßR2) chez une enfant de 4ans avec anévrysme de l'aorte thoracique.

Loeys-Dietz syndrome is a rare form of connective tissue disorder, whose clinical features can resemble those of Marfan syndrome, but with a more unpolished appearance. Recently brought out, this pathology remains little known; however, its consequences may be dramatic. We report on the case of a 4-year-old girl followed for a congenital hip dislocation, in which a systematic exam found increased cutaneous elasticity and a bifid uvula, suggesting a connective tissue disorder. Symptoms were unpolished, as the child's height was normal, without any positive cardiac, rheumatological, or ophthalmological family history. Cardiovascular tests found a thoracic aortic aneurysm at the Valsalva sinus (26mm, Z-score=+4.24). A genetic investigation found a TGFßR2 gene mutation, leading to the diagnosis of Loeys-Dietz syndrome type 2. Skeletal damage associated with bifid uvula and/or hypertelorism and an aneurysm of the ascending aorta should guide the genetic investigation to the search for TGF-ß vasculopathy such as Loeys-Dietz syndrome.