Ehlers-Danlos Syndromes (EDS)

Overview

• EDS consists of 13 heritable connective tissue disorders caused by genetic changes.
• Common features across all types include:
  • Joint hypermobility
  • Skin hyperextensibility
  • Tissue fragility

Key Features

Joint Hypermobility

• Greater range of motion in joints; can be painless or cause joint instability.
• Joint instability leads to subluxations, dislocations, sprains, injuries, and pain.
• Hypermobility varies by type, commonly observed in hands and feet.

Skin Hyperextensibility

• Skin stretches beyond normal range, measured at forearm.
• Mild to severe hyperextensibility varies, certain EDS types show more.
• Other skin symptoms: unusual texture, fragility, thinness, poor wound healing, abnormal scarring.

Tissue Fragility

• Organs and structures are more vulnerable to damage.
• Symptoms include easy bruising and poor wound healing.
• Severe fragility affects skin, blood vessels, organs, eyes, gums, bones.

Types of EDS

• Hypermobile EDS (hEDS): Most common, generalized joint hypermobility, instability, chronic pain.
• Classical EDS (cEDS): Fragile skin, atrophic scarring, stretchy skin.
• Vascular EDS (vEDS): Arterial fragility, organ rupture, extensive bruising.
• Other types include rare forms with specific genetic mutations and distinct symptoms.

Prevalence

• hEDS: 1 in 3,100-5,000 (most common).
• cEDS: 1 in 20,000-40,000.
• vEDS: 1 in 100,000-200,000.
• Other types: Less than 1 in 1,000,000.

Causes

• Variants in genes affecting collagen and connective tissue proteins.
• Genetic causes of hEDS are unidentified but suggest a dominant inheritance pattern.

Inheritance Patterns

• Dominant: One copy needed; each child has a 50% inheritance chance.
• Recessive: Two copies needed, one from each parent.
• De novo mutations can occur.

Symptoms

• Symptoms vary by type; common signs include joint hypermobility, pain, fatigue.
• Other conditions often coexist, such as dysautonomia and mast cell diseases.

Diagnosis

• Each EDS type has specific clinical diagnostic criteria.
• Genetic testing confirms diagnosis except for hEDS.
• hEDS diagnosed through clinical criteria; no genetic test available.
• Hypermobility spectrum disorders (HSD) considered for symptomatic joint hypermobility not meeting EDS criteria.

Management

• No disease-specific treatments; symptom-based management.
• Requires a multi-specialty care team.
• Individualized care plans.

History

• Named after Dr. Edvard Ehlers and Dr. Henri-Alexandre Danlos.
• Classification evolved over time, latest in 2017.
• 2017 classification includes 13 types, introduces HSD.

Classification

• Current classification uses descriptive names, no Roman numerals.
• Research ongoing to identify new genetic variants possibly indicating new EDS types.

Other Information

• Emphasizes the importance of awareness, support groups, and research.