Ehlers-Danlos Syndrome
Edited by Frederick A. Matsen, III, M.D. and Gregory C. Gardner, M.D.
Last updated August 31, 2001
About Ehlers-Danlos syndrome

What is it?
Ehlers-Danlos syndrome (EDS) is a group of hereditary disorders that affects mainly the skin and joints, but other organs as well. EDS results in weakness and/or excessive flexibility of the connective tissues of the body. People with EDS are born without the ability to make certain components of the normal connective tissue of the body.

Incidence and risk factors
EDS is a relatively rare disorder, occurring in fewer than 1 in 20,000 people. The various forms of EDS are characterized by abnormalities in the chemical structure of the body's connective tissues (for example, skin, muscles, tendons and ligaments). As a result, skin may become fragile and joints unstable.

Causes

Genetics
This section gives a brief description of how EDS is inherited.

Before reading about heredity, understand that parents have no control over which genes they pass on to their children or receive from their parents. Therefore, parents should not feel at fault if one or more of their children inherits EDS.

An inherited disorder is one that is passed on within families from one generation to the next. It is a result of a change (mutation) in one of the 50,000 or so genes found on the chromosomes (the thread-like structures found in the center of each cell). Genes are like blueprints that direct the development and function of every cell in a person's body.

Genes and chromosomes exist in pairs. At the time of conception, one half of each gene pair is passed on to the child from each parent. The new gene pairs determine which features or traits the child inherits.

Most inherited genes are normal. However, sometimes a gene changes from its original form. This change is called a "mutation." The exact reasons why a mutation occurs are usually unknown. Mutations can occur frequently. Most mutations are not harmful, but occasionally a mutant gene functions improperly and causes a disorder, malfunction or malformation. Different mutations of connective tissue genes cause the distinct forms of EDS.

There are three different ways in which the various types of EDS can be inherited: autosomal dominant, autosomal recessive and X-linked recessive inheritance. A family with one type of EDS will not develop another type, and the inheritance pattern will be the same within a family.

Autosomal Dominant Inheritance is the way in which the most common forms of EDS such as Types I and II are inherited. With this type of inheritance pattern, the EDS gene is dominant. This means it overrides the effects of the other gene in the pair. Therefore, if a parent who has EDS contributes the Ehlers-Danlos gene and the other parent contributes a normal gene, the child will inherit the disorder. This results in a 50% chance of passing EDS on to each child. On the other hand, both parents may contribute a normal gene, so there is also a 50% chance that each child will not have EDS.

Autosomal Recessive Inheritance is the way in which EDS VI, VII and X are inherited. In recessive inheritance, the disorder is only inherited if both genes in the gene pair are EDS genes. For a child to be affected, both parents must pass on an EDS gene. With each pregnancy, there is a 25% chance that each child will have the disorder. There is a 50% chance that a child will not be affected, but will inherit one EDS gene and be a "gene carrier." A carrier is unaffected, but carries the EDS gene which can be passed on to his or her children. A carrier could have children affected with EDS only if the carrier's spouse also carries an EDS gene.

X-Linked Recessive Inheritance is the way in which EDS V is inherited. With X-linked recessive inheritance, genes are transmitted on the "X" chromosome which also carries genes that determine the sex of the child. If a woman carries an EDS gene, there is a 50% chance that her sons will inherit EDS and a 50% chance that her daughters will be gene carriers. If a man carries an EDS gene, all of his daughters would be gene carriers, but none of his sons would be affected and none would be carriers.

This material may not have answered all of your questions. We encourage you to discuss your concerns with a genetic counselor or with a knowledgeable doctor. Contact your local chapter of the March of Dimes for a listing of genetic counseling centers in your area.

Symptoms and diagnosis

 
Figure 1 - Loose, unstable joints

Symptoms
At least 9 different types of EDS have been identified; symptoms vary depending on which type of EDS a person has.

Symptoms vary depending on which type of EDS a person has. The most common forms of Ehlers-Danlos syndrome (EDS Type I and II) are characterized by one or more of the following features:

skin problems
soft velvet-like skin
fragile skin that bruises or tears easily
stretchy rubber band-like skin
easy or severe bruising
poor and slow wound healing (usually taking weeks to months to heal)
small harmless bumps under the skin
joint problems
loose unstable joints causing frequent dislocations usually occurring in the shoulders, knees, hips, collar bone or jaw (see figure 1)
double jointedness (hyper extensible joints), extreme in some cases
joint pain from frequent dislocation
eye problems
nearsightedness, occasionally extreme

Less common symptoms that may occur in the more rare forms of EDS include:

gum disease (EDS) VIII)
curvature of the spine (EDS VI)
problems with blood clotting (EDS X)
more serious eye conditions (EDS VI)
pulmonary (lung) problems (EDS IV)
weak blood vessels, intestines or uterus that may lead to more serious complications (EDS IV)

Diagnosis
Specific diagnostic tests are available for some types of EDS in which there is a known biochemical defect. Doctors will also review your family and medical histories and perform a complete physical examination.

Having EDS is more than being limber or double-jointed. "Over extension" is the ability to flex the joints beyond normal limits.

Sometimes, a skin biopsy may be performed to study the chemical make-up of the connective tissue. (A biopsy is a simple, almost painless procedure in which a tiny piece of skin is removed for examination in the laboratory.).

Health care team
Because Ehlers-Danlos is uncommon, it is important to find a doctor who has experience with its diagnosis and treatment. Many family doctors, pediatricians, arthritis specialists, skin specialists and specialists in medical genetics are able to diagnose and/or treat Ehlers-Danlos syndrome. If you are unable to find a knowledgeable doctor in your area, contact the Ehlers-Danlos National Foundation for a referral.

Management and treatment

Treatment
Treatment will vary, depending on how EDS affects you. One or more of the following treatments and precautions may be recommended.

Because serious complications can occur in the more rare forms of EDS, regular check-ups with specialists familiar with EDS are recommended. Ask your doctor to describe the symptoms of any possible complications and what to do should these occur.

Surgery
People with EDS may need surgery to correct fractures and dislocated joints. If you are scheduled for any type of surgery be sure to tell the surgeons that you have Ehlers-Danlos syndrome so that surgeons may choose to use staples or tape (rather than stitches) to close wounds. Surgeons should also be alerted to any vascular or bleeding problems.

Pregnancy
Some forms of EDS (especially EDS IV) can cause serious complications such as bleeding or tearing during childbirth or premature births. Any woman who has Ehlers Danlos syndrome should discuss pregnancy with a doctor who is familiar with EDS and its complications.

Exercise
Joint stability may be improved through prescribed exercise programs that strengthen the muscles. But avoid weightlifting. It puts too much strain on your joints. In fact, any exercises that cause you to put pressure on locked joints should be avoided. Check with your doctor or physical therapist to learn appropriate strengthening exercises and the proper way to do them.

Self-management
Learning how to protect your joints will help prevent further injury, reduce pain, conserve energy and enable you to stay as active as possible. Recognize activities that cause joint pain and find less painful ways to move and perform tasks.

Avoid activities that cause you to overextend or "lock" your joints. Frequent over extension of the joints may cause chronic "traumatic" arthritis. For example, avoid leaning on or pushing off with the palms of your hands. These movements cause fingers to hyperextend.

Prevent slips and falls at home by keeping walkways, entrances and exits clear of toys and other objects. Don't use scatter rugs and avoid using slippery floor polish. Toddlers and young children should be encouraged to wear knee pads to protect their knees if they do fall.

Consider using self-help devices, such as long-handled combs and reachers, if reaching or stretching puts your joints at risk for injury or dislocation. Most devices can be found in hardware or variety stores, pharmacies or medical supply shops.

How you store routinely used items can also make a difference. Are items within easy reach? If not, rearrange storage areas and place items at comfortable heights. If stair-climbing puts excessive strain on your knees or hips, consider placing a ramp over the steps. Duplicate items upstairs and downstairs to avoid frequent trips up and down steps. Identify other ways to make your home or work area safe and comfortable. Be creative and see what works for you.

Eye treatments

Children and adults should have regular eye exams. Nearsightedness (myopia) is a common condition and can be corrected with prescription glasses or contact lenses. People with EDS VI are particularly at risk for more serious eye conditions and need to consult a doctor who has experience treating EDS.

Vitamin C

Vitamin C (ascorbic acid) may or may not be effective in reducing the severity of symptoms for some people with EDS VI and possibly other types. Be sure to check with your doctor before taking supplemental doses of vitamin C.

Sun exposure

Premature aging due to sun exposure is a risk for many people with Ehlers-Danlos syndrome. When out-of-doors during peak daylight hours use a sunscreen with a protection factor of 15 or above and wear long sleeves, long pants and a wide brimmed hat.

Coping with EDS

Coping
If you or your child has EDS, you know that it may present many challenges.

Adults and children may initially react with feelings of fear, anger or depression. Children may also feel self-conscious about having the disorder. Try to remember that it often takes time to adjust to having a chronic (long-lasting) disorder, but that many people with Ehlers-Danlos syndrome are able to live full, relatively active lives.

 

If you have EDS you might have concerns about managing pain, maintaining independence, financial strain or family worries. Discussing your problems and learning new ways to manage daily activities will help you cope more effectively. Your family may be one of your best sources of support. Discuss these issues with them, and ask for their support.

 

It is important that parents discuss their child's symptoms with teachers, neighbors, relatives, baby-sitters and friends. They need to understand that cuts and bruises are common features of the Ehlers-Danlos syndromes, and not signs of child abuse. They also need to know about the following:

The degree to which your child can participate in physical education classes, playground and other recreational or special activities.
Medications your child must take during the day.
Routine precautions such as:
discouraging your child from overextending his or her joints as entertainment for siblings and other children
avoiding rough-housing or wrestling with siblings and other children
joint protection techniques and other safety precautions

 

Although children with EDS may need special protection, they also need to play and have friends. Involve your children in activities they can safely enjoy. Ehlers-Danlos syndrome does not affect intelligence, but medical problems may interfere with progress in school or the child's social or psychological adjustment.

 

Children with disabilities have legal rights to a free and appropriate public education, along with special services. For further information about special needs of children and educational rights, consult our article on juvenile arthritis.

 

For more information on parent advocacy, contact your local chapter of the Arthritis Foundation or the American Juvenile Arthritis Organization (AJAO).

Asking for help
You might find it helpful to talk with a health professional such as a medical social worker, psychologist, genetic counselor, or clergyman about your illness and how it affects you and your family. Ask your doctor for a referral or contact your local church or family social service agency.

Many people gain support by sharing their concerns with other people who have the disorder. The Ehlers-Danlos National Foundation can provide you with names of both children and adults with EDS who live in your area. Children, especially, may wish to talk to other children who have EDS.

Support services exist for people who may be more severely disabled. For more information, contact the State Crippled Children's Services, Department of Vocational Rehabilitation or the Social Security Administration's Supplemental and Disability Insurance Income Program.

Research

Medical researchers are studying inherited disorders of connective tissue. By analyzing the chemical make-up of connective tissue and the results of gene mutations, they will some day find ways to treat EDS more effectively, and perhaps cure or prevent these disorders.

Credits
Some of this material may also be available in an Arthritis Foundation brochure.