Ehlers-Danlos syndrome is the name given to a group of conditions that are inherited. Inherited conditions are passed on from your relatives through material in cells, called genes. A faulty inherited gene means that there is a problem with the formation and structure of collagen and connective tissue in the body. This leads to stretchy skin, loose joints and fragile blood vessels and body tissues. Treatment is aimed at trying to protect the skin and joints from further damage.
What is Ehlers-Danlos syndrome and what causes it?
Ehlers-Danlos syndrome (EDS) is the name given to a group of conditions that are inherited through the material contained in the nucleus of a cell, called genes. There is a problem with the formation and structure of collagen and connective tissue in the body.
Connective tissue is a fibrous tissue that gives support and structure and binds, or connects, parts of the body together. Collagen is a type of protein and is one of the main components of connective tissue. There are over thirty different types of collagen, found in different parts of the body. More than 80% of the skin is made up from collagen. Collagen is also found in the tendons, ligaments and cartilage around joints, as well as the blood vessels.
In someone with EDS, faulty genes mean that the amount of collagen in their body can be reduced and/or the collagen and connective tissue can be weaker. It can affect the skin, joints and blood vessels throughout the body leading to:
- Fragile and stretchy (hyperelastic) skin.
- Unstable and loose (hypermobile) joints.
- Fragile blood vessels and body tissues.
There are six main types of EDS that cause different problems and affect the body in different ways. The different types of EDS depend on which of the different types of collagen are affected and in what part of the body.
It is called Ehlers-Danlos syndrome after Edvard Ehlers and Henri-Alexandre Danlos who recognised and described the features of the group of conditions in the early 1900s.
How common is Ehlers-Danlos syndrome and who gets it?
EDS runs in families and is an inherited condition. Inherited conditions are passed from parents through material contained in the nucleus of a cell, called genes. Genes control how the cell and the body work. It used to be said that EDS affected about 1 in 5,000 people. However, one type of EDS (hypermobile EDS) is not diagnosed as often as it should be. Therefore, this condition may affect a lot more people than was originally thought. Even though the problem with connective tissue and collagen is there from birth, the syndrome is not usually diagnosed until early adulthood. This is because it may take some time before the symptoms and signs become more obvious (see below). The arthrochalasia and dermatosparaxis types, however, are diagnosed mainly in childhood.
What are the symptoms of Ehlers-Danlos syndrome?
Not everyone with EDS will have the same symptoms. The symptoms can vary according to the type of EDS that a person has.
The six main types of EDS are known as:
- Classic type
- Hypermobile type
- Vascular type
- Kyphoscoliosis type
- Arthrochalasia type
- Dermatosparaxis type
Below are some of the more common symptoms with EDS. One person may not have all of these symptoms.
The joints are loose (hypermobile) and hyper-extensible which means that they have a greater than normal range and degree of movement - they are very flexible. These joint problems are often described as 'double-jointed' by some people.
Dislocations of joints may easily occur. Joint pains are also common and curvature of the spine (scoliosis) may develop in some people. Children with hypermobile joints can take longer than average to sit, stand or walk. Note: people with the vascular type of EDS often do not develop joint problems.
In all types of EDS except the vascular type, the skin feels soft and stretchy - a bit like dough. It is also very easy to pull the skin upwards and away from the body - it appears to be very elastic. When you let go, the skin immediately returns to its normal position.
The skin may also be very delicate so that it bruises and becomes injured easily. This is because blood vessels near to the skin surface may be very delicate and fragile and can be damaged easily. Problems with skin healing and excessive scarring may be a problem in some people. In the vascular type, the skin may look as if you can see through it (translucent) so that you can see blood vessels underneath the skin.
Weakness of the muscles
This may be noticed perhaps by difficulty walking, falling over frequently or because of problems controlling the movements of the body. In more severe cases, people may need a stick or a wheelchair to help them walk or get about. Poor grip and difficulty writing may also be a problem for some people. Sometimes trouble with speaking can occur because the muscles that help the person to speak are weakened.
Other symptoms and problems
- Firm lumps a few centimetres across over the elbows and the knees develop in some people with EDS.
- Varicose veins may also be more common than in the general population.
- Teeth problems, including delay in teeth coming through (teeth eruption), can occur. Sometimes not all permanent teeth may ever appear.
- In some women with EDS, pregnancy may be difficult and dangerous because there is a risk of bleeding.
- Weak collagen can also lead to problems inside the body. It may make the heart valves or the walls of the large artery leading from the heart (the aorta) weak.
- Collagen weakness of the intestines can cause hiatus hernia, constipation and irritable bowel syndrome.
- People with the hypermobile type can develop asthma-type symptoms due to collagen changes in the lungs.
- The hypermobile type can also be associated with nervous system symptoms such as headaches, persistent body pains and tiredness.
- Psychological difficulties can include anxiety and panic disorders.
- Some types of EDS cause eye changes. The areas around the pupils may be blue rather than white and the eyeballs themselves may be very fragile.
How is Ehlers-Danlos syndrome diagnosed?
EDS is sometimes quite difficult to diagnose. It is usually suspected because of the typical symptoms. The doctor may ask about close family members and any problems and symptoms they may have had with their skin or joints.
Sometimes, a sample (biopsy) of the skin may be suggested to help confirm the diagnosis. The skin biopsy may allow doctors to determine which type of EDS a person has. It is a simple procedure which is usually done under a local anaesthetic. A small sample of skin a few millimetres across is taken (usually from the inner arm). One or two stitches may then be needed to close the skin back up. The skin sample is then examined underneath the microscope in the laboratory. Typical changes in the skin can be seen in the different types of EDS. Skin cells can also be analysed to see whether there are any problems with the material that makes up the cells, called genes.
What is the treatment for Ehlers-Danlos syndrome?
There is no specific treatment for EDS. Treatment is generally aimed at trying to protect the skin and the joints from further damage.
People living with EDS need to think about and use their joints carefully and sensibly. They should be careful to avoid heavy lifting and contact sports, so as to minimise any trauma to their joints. Protective splints and joint supports may be helpful. Physiotherapists may be able to help and advise about the balance between rest and exercise. Walking aids such as sticks and wheelchairs may sometimes be needed. Occupational therapists may be able to advise about home adaptation and aids to help with daily living.
Painkillers may help with joint pains. Sometimes vitamin C supplements may be suggested, as vitamin C may lessen the tendency to bruise easily.
A medication called celiprolol may be given to people with the vascular type of EDS, to prevent the walls of large blood vessels from splitting and bursting.
If someone has EDS, it may be helpful for them to talk to a genetic counsellor to discuss the risk of them passing on EDS to any future children.
What is the outlook (prognosis) for Ehlers-Danlos syndrome?
The outlook depends on which type of EDS a person has. If someone has the type that affects the blood vessels (the vascular type) then there is a risk of bursting (rupture) of large blood vessels in the body. There is also a risk of rupture of the internal organs. With other types of EDS, there is not this same danger. Most people with EDS are generally able to lead healthy and full lives.
Further help & information
Dr Michelle Wright
Dr Laurence Knott
Dr John Cox