What is Loeys-Dietz Syndrome?

Loeys-Dietz Syndrome is also a genetic Connective Tissue Disorder with some similarities to Marfan syndrome, with patients sometimes referred to as atypical Marfan syndrome patients.  The disorder was first discovered and named by Dr Bart Loeys and Dr Hal Dietz who both noted a specific gene mutation (change) at the Johns Hopkins School of Medicine, Baltimore, USA in 2005.  The first genetic information was then confirmed in 2006. 

Loeys-Dietz syndrome is the result of a mutation of either of five currently known genes - transforming growth factor beta receptor 1 and transforming growth factor beta receptor 2 (TGFBR 1 and TGFBR 2), SMAD3, TGF Beta2 and TGF Beta 3.  As with Marfan syndrome, it is an autosominal dominant disorder, meaning an affected person has a 50/50 chance of passing directly to children.  The syndrome does not skip generations.  Again, similarly to Marfan syndrome it is expected that 75% of cases are directly inherited and 25% are spontaneous mutation (first occurrence in the family).

Loeys-Dietz Syndrome is known to affect the –

• Cardiovascular System (Heart and Blood Vessels) - Aortic dilation or aneurysm;  Aortic dissection; Mitral Valve Prolapse.  Unlike with Marfan Syndrome, Loeys-Dietz Syndrome affects the main arteries throughout the body, including the brain.  This means that aneurysms can be found outside of the Aorta.  Congenital heart defects such as PDA can also be linked to Loeys-Dietz Syndrome.

• Skeletal System (Bones and Joints) – Tall and thin stature; Scoliosis or Kyphosis; Pectus Excavatum or Pectus Carinatum; Long fingers and toes; Hypermobile joints; Flat feet; Overcrowding of teeth; cleft palate; split uvula; craniofacial deformities – flat cheekbones, blue tinge to the white of the eyes, early fusion of skull bones, small chin.

• Ocular System (Eyes) – Severe Myopia; wide spaced eyes, blue sclera (white of eyes with a blue tinge)

• The following can also be found – Dural Ectasia; wide/stretched scarring; soft and translucent skin; easy bruising; hernias. 

• Research is also currently being carried out into a possible link between allergies and gastrointestinal problems in patients with Loeys-Dietz Syndrome

• The intestine, spleen and uterus may be prone to rupture.