Loeys-dietz syndrome

Loeys, 2005

Rare multi-organ disease that clinically overlaps with Marfan syndrome (MFS) in some organ manifestations. However, the lens shift, which is one of the diagnostic criteria in MFS, is always absent. On the other hand, LDS presents with symptoms that are uncommon in MFS.

People with Loeys-Dietz syndrome often develop immunological disorders: food allergies, asthma or signs of atopic dermatitis or inflammatory bowel disease.

To date, five different genotypes are known in Loeys-Dietz syndrome, referred to as types I through V.

The five types of Loeys-Dietz syndrome are distinguished according to their genetic cause:

• TGFBR1 gene mutations cause type I
• TGFBR2 gene mutations cause type II
• SMAD3 gene mutations cause type III
• TGFB2 gene mutations cause type IV
• TGFB3 gene mutations cause type V.

These five genes play a role in the TGF-β signaling pathway, which controls the functions of body cells during growth and development. This signaling pathway also regulates the formation of the extracellular matrix. The defective proteins encoded by these genes lead to a pathological increase in the activity of the TGF-β signaling pathway. This disrupts the development of the extracellular matrix and various body systems.

The signs and symptoms of Loeys-Dietz syndrome can occur from childhood into adulthood. The severity varies.

Hypertelorism and a split uvula or cleft palate are particularly noticeable.

The following symptoms can also occur, but are not necessarily present in every patient:

• Aneurysm of the aortic root and other vascular areas
• Dissections of the aorta and other major vascular systems
• Tortuosity of the arteries
• Retinal detachments
• Blue shimmering leather skin (sclera)
• Striae cutis distensae
• Translucent veins
• Tendency to hematomas
• Soft, delicate skin with atrophic scars
• Curvature of the spine
• Deformation of the sternum inwards or outwards
• Clubfoot
• Narrow, high palate
• Hypermobility of the joints
• Slender hands with long fingers (spider fingers)
• Skull malformations due to premature ossification (craniosynostosis)

Causal therapy not possible. Organ-related clinical controls and therapies.

As in Marfan syndrome, the prognosis of the disease depends on the cardiological involvement.

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