Ehlers-Danlos syndrome (EDS) is the name given to a group of genetic disorders characterized by weakness in the connective tissue which makes up joints and blood vessels, and holds tissues together. While the symptoms of the different types of EDS often overlap, dermatosparaxis EDS (dEDS) is mainly characterized by soft doughy skin that is very fragile, as well as hernias and joint hypermobility (when joints can move farther than they should).
dEDS is extremely rare, with only a few cases having been reported in the literature.
What causes dEDS?
dEDS is caused by mutations in a gene called ADAMTS2, which encodes for an enzyme that is involved in the process of making collagen, an important structural protein. The ADAMTS2 enzyme processes immature collagen proteins and turns them into their functional form — a strong, slender fiber that provides elasticity to tissues.
Collagen is an important component of the connective tissue that gives shape to muscles and joints, holds organs together, and provides structure to the skin. In dEDS, the connective tissue is not formed correctly, which leads to the symptoms of the disease.
How is dEDS inherited?
Most dEDS is inherited, but the patients’ parents may have had no symptoms of the disease. In some very rare cases, the disease can develop as a result of a new mutation.
For most genes in the body, humans have two copies — one inherited from each parent. dEDS is passed on in an autosomal recessive manner, meaning that patients must have a disease-causing mutation in both copies of the ADAMTS2 gene to develop the disease — one from the mother and one from the father. Most likely, the parents never experienced any disease symptoms themselves, because each had only one copy of the disease-causing mutation and one healthy copy of the gene.
If both parents are carriers (that is, each parent has one copy of the disease-causing mutation), their children have a one-in-four chance of inheriting two copies of the disease-causing gene mutation and developing dEDS, and a one-in-two chance of inheriting only one copy of the disease-causing mutation and being carriers just like their parents.
What are the symptoms of dEDS?
People with dEDS have soft, doughy skin that is very fragile. Many patients have saggy excess skin that develops folds, especially on the face, and leads to a characteristic appearance. They bruise easily and often develop hernias — a condition in which the intestines push through the muscle of the abdomen in the stomach or groin area.
dEDS patients also have joint hypermobility — their joints can bend more than normal, leading to frequent dislocations. These dislocations may need to be treated surgically to reset the joint. Frequently, dEDS patients have abnormalities in the shape and angle of their hip joints, making those joints more likely to dislocate.
How is dEDS diagnosed?
dEDS is diagnosed with a physical examination, which includes a test of joint mobility called the Beighton scoring system. To perform the test, the angle to which patients can bend their joints without pain is measured for each joint: fingers, thumbs, elbows, knees, and spine. The patient gets a score for each joint that can be bent more than normal, and the combined score is used as a measure of hypermobility.
To confirm a diagnosis of dEDS, the physician can order a genetic test in which a small sample of blood is drawn from the patient and sent to a laboratory to be examined for any mutations in the ADAMTS2 gene. The test results are usually available within four to six weeks. The doctor then meets with the patient to discuss the results and whether any further testing is needed.
How is dEDS treated?
With no cure currently available for dEDS, patient care is targeted at reducing the symptoms of the disease.
Patients can undergo physiotherapy to strengthen their muscles and reduce the frequency of joint dislocations. Surgery may be needed for some people with dEDS to correct problems such as hernias or dislocated joints.
Last updated: Oct. 31, 2019
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Ehlers-Danlos News is strictly a news and information website about the disease. It does not provide medical advice, diagnosis, or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.