U01.01.032 Ehlers-Danlos syndrome

Ehlers-Danlos syndrome (EDS) is a group of connective tissue disorders characterized by defective collagen synthesis, resulting in a variety of clinical manifestations, including hyperextensible skin, hypermobile joints, and a tendency to bleed (easy bruising).

Clinical Manifestations

Hyperextensible Skin (A)
Hypermobile Joints (B)
Tendency to Bleed (Easy Bruising)

Types of Ehlers-Danlos Syndrome

EDS has multiple types with varying severity and inheritance patterns. The types differ in their clinical presentations and the specific mutations involved.

Type	Clinical Features	Genetic Mutation
Hypermobility Type	Most common; joint instability and hypermobility.	Unknown genetic cause.
Classical Type	Joint and skin symptoms, including hyperextensibility of skin.	Mutation in type V collagen (COL5A1, COL5A2).
Vascular Type	Fragile tissues, including vessels (e.g., aorta), muscles, and organs prone to rupture (e.g., gravid uterus).	Mutation in type III collagen (COL3A1).

Inheritance Patterns

Autosomal Dominant: Most common inheritance pattern.
Autosomal Recessive: Less common, can also be observed in some subtypes.

Associated Complications

Joint Dislocation
Berry and Aortic Aneurysms
Organ Rupture (e.g., Gravid Uterus)

Points to Remember

Hypermobility type is the most common form of EDS, characterized by joint instability.
Classical type involves mutations in type V collagen (COL5A1, COL5A2) and presents with both joint and skin symptoms.
Vascular type is associated with fragile tissues and mutations in type III collagen (COL3A1), leading to a high risk of vessel and organ rupture.
Severity and inheritance vary depending on the subtype.

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