Ehlers-Danlos syndrome (EDS) is a complex group of rare hereditary disorders involving connective tissues. Connective tissues are the tissues that support parts of the body. Examples of connective tissues are skin, tendons, ligaments, and cartilage. EDS usually results in over-flexible (hypermobile) joints, over-elastic (hyperelastic) skin, and fragile tissues. There are at least six different varieties of EDS, classified according to how they are inherited and which structures of the body they mostly involve.

Causes

EDS is caused by defects in the genes that control the formation of connective tissue. The specific genetic defect in most types of EDS affects the production of collagen. Collagen is a structural protein. It strengthens and provides elasticity to connective tissue.

Risk Factors

A risk factor is something that increases your chance of getting a disease or condition. Risk factors for EDS include:

• Family members with EDS

Symptoms

The severity of EDS symptoms varies from mild to very severe and debilitating. Symptoms depend on the specific type of EDS.

The most common symptoms of EDS include:

• Loose, unstable joints that are prone to:

• • Swelling

• • Sprains

• • Dislocations

• • Hyperextension

• • Arthritis

• • Flat feet

• • Deformities of the thoracic spine, such as:

• • Scoliosis – curvature of the spine

• • Kyphosis – a thoracic hump

• Soft, fragile skin that stretches far too easily; as a result:

• • Skin is prone to bruise easily.

• • Minor injuries can result in gaping wounds.

• • Wounds heal slowly and poorly.

• • Suturing skin is difficult because skin tends to tear.

• • Skin scars easily from wounds or stretching.

• • Fleshy outgrowths may form on top of scars.

• • Calcified nodules may form under the skin.

• • The risk for surgical complications is greater due to deep tissue fragility.

Other symptoms of EDS may include:

• Eye problems, such as:

• • Nearsightedness (common in adults with EDS)

• • Epicanthic fold – vertical fold of skin on either side of the nose, sometimes covering the inner corner of the eye (common in children with EDS)

• • Fragile sclera, which forms the white outer coat of the eyeball

• • Perforation of the globe of the eye (rare)

• Lung problems due to lose of normal elastic tissue

• Chronic musculoskeletal pain

• Weak blood vessels, which can lead to aortic aneurysms and spontaneous rupture of large blood vessels

• Problems with blood clotting, leading to easy bruising and bleeding

• Mitral valve prolapse (a heart valve problem)

• Susceptibility to gum bleeding and diseases

• Gastrointestinal problems, such as:

• • Hernias

• • Diverticulosis

• • Perforation or bleeding along the gastrointestinal tract

• Pregnancy-related problems, such as:

• • Premature birth

• • Early rupture of membranes

• • Bleeding during pregnancy and excessive bleeding during or after childbirth

• • Uterine rupture

• • Higher complications from procedures such as episiotomy and Cesarean section

Diagnosis

The doctor will ask about your symptoms and medical history, and perform a physical exam. This is usually sufficient to diagnosis most cases. When the diagnosis is uncertain, tests may include:

• Skin biopsy – removal of a sample of skin tissue to look for abnormalities in the connective tissue

• Detection of specific biochemical defects – available for certain types of EDS

Treatment

There is no known cure for EDS. Treatment usually involves treating symptoms and trying to prevent complications.

Prevention

There is no known way to prevent EDS once a person is born. If you have EDS or have a family history of the disorder, you can talk to a genetic counselor when deciding to have children.

RESOURCES:

Ehlers-Danlos National Foundation
http://www.ednf.org

National Institute of Arthritis and Musculoskeletal and Skin Diseases
http://www.niams.nih.gov

National Organization of Rare Disorders
http://www.rarediseases.org

References:

Ehlers-Danlos Foundation website. Available at: http://www.ednf.org.

National Institute of Arthritis and Musculoskeletal and Skin Diseases website. Available at: http://www.niams.nih.gov.

National Organization of Rare Disorders website. Available at: http://www.rarediseases.org.

The Merck Manual of Medical Information. Simon and Schuster, Inc.; 2000.