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Ehlers-Danlos Syndromes


Frank Pessler

, MD, PhD, Helmholtz Centre for Infection Research

Reviewed/Revised Dec 2022
Topic Resources

Ehlers-Danlos syndromes are rare hereditary disorders of connective tissue that result in unusually flexible joints, very elastic skin, and fragile tissues.

  • These syndromes are caused by a defect in one of several genes that control the production of connective tissue.

  • Typical symptoms include flexible joints, a humpback, flat feet, and elastic skin.

  • The diagnosis is based on symptoms and results of a physical examination.

  • Most people with this syndrome have a normal life span.

  • There is no cure for Ehlers-Danlos syndromes.

Ehlers-Danlos syndromes are caused by an abnormality in one of the genes that controls the production of connective tissue. Connective tissue Overview of Connective Tissue Disorders in Children Connective tissue is the tough, often fibrous tissue that binds the body's structures together and provides support and elasticity. Muscles, bones, cartilage, ligaments, and tendons are built... read more is the tough, often fibrous tissue that binds the body's structures together and provides support and elasticity.


There are 6 major types of Ehlers-Danlos syndrome and 7 less common types. They involve different genes and vary widely in severity. Although the types have slightly different symptoms, they all result in abnormally fragile connective tissue, which causes problems in joints and bones and may weaken internal organs.

Symptoms of Ehlers-Danlos Syndromes

People with an Ehlers-Danlos syndrome usually have very flexible joints, abnormal scarring, poor wound healing, fragile blood vessels, and very elastic skin. The skin can be stretched up to several inches but returns to its normal position when released.

Some people develop small, hard, round lumps under the skin.

In a small number of people, the blood does not clot normally, so bleeding from minor wounds may be difficult to stop.

Complications of Ehlers-Danlos syndromes

Ehlers-Danlos syndromes may alter the body’s response to injuries. Minor injuries may result in wide gaping wounds. Although these wounds usually do not bleed excessively, they leave wide scars.

Sprains and dislocations develop frequently.

Sometimes weak tissue in a heart valve causes the valve to leak.

If a pregnant woman has an Ehlers-Danlos syndrome, delivery may be premature Preterm Labor Labor that occurs before 37 weeks of pregnancy is considered preterm. Babies born prematurely can have serious health problems. The diagnosis of preterm labor is usually obvious. Measures such... read more . The mother's fragile tissues increase risk that her uterus may rupture during labor. Poor skin healing may make an episiotomy or cesarean delivery (C-section) problematic. If the fetus has an Ehlers-Danlos syndrome, the amniotic sac may rupture early (prelabor rupture of membranes Prelabor Rupture of the Membranes (PROM) Prelabor rupture of the membranes is the leaking of amniotic fluid from around the fetus at any time before labor starts. After the membranes rupture, labor often soon follows. If labor does... read more ). A mother or baby who has an Ehlers-Danlos syndrome can bleed excessively before, during, and after delivery.

Diagnosis of Ehlers-Danlos Syndromes

  • A doctor's evaluation

  • Genetic testing

  • Skin biopsy

  • Imaging tests to detect complications

A doctor bases the diagnosis of an Ehlers-Danlos syndrome on the symptoms and results of a physical examination.

To confirm the diagnosis, genetic tests are usually done.

The doctor can identify some of the types of Ehlers-Danlos syndrome by taking a sample of skin to examine under a microscope (biopsy).

Other tests are done to check for conditions that are associated with complications. For example, echocardiography Echocardiography and Other Ultrasound Procedures Ultrasonography is a type of medical imaging that uses high-frequency (ultrasound) waves to produce a moving image of internal organs and other tissues. Echocardiography is ultrasonography of... read more Echocardiography and Other Ultrasound Procedures and other imaging tests are usually done to detect problems with the heart or blood vessels.

Prognosis for Ehlers-Danlos Syndromes

Despite the many and varied complications people with an Ehlers-Danlos syndrome may have, their life span is usually normal.

However, potentially fatal complications (usually bleeding) occur in certain types.

Treatment of Ehlers-Danlos Syndromes

  • Injury prevention

There is no way to cure an Ehlers-Danlos syndrome or to correct the abnormalities in the connective tissue.

Injuries can be treated, but it may be difficult for a doctor to stitch cuts because stitches tend to tear out of the fragile tissue. Usually, using an adhesive tape or medical skin glue closes cuts more easily and leaves less scarring.

Special precautions should be taken to prevent injuries. For example, children with severe forms of Ehlers-Danlos syndromes can wear protective clothing and padding.

Surgery requires special techniques that minimize injury and ensure that a large supply of blood is available for transfusion.

An obstetrician (a doctor who specializes in childbirth and in caring for and treating women who are giving birth) must supervise pregnancy and delivery.

Genetic counseling for family members is suggested.

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