Facts you should know about Ehlers-Danlos syndrome
Joint hypermobility is a sign of Ehlers-Danlos syndrome.
- Ehlers-Danlos syndromes are a group of disorders which share common features including easy bruising, joint hypermobility (loose joints), skin that stretches easily (skin hyperelasticity or laxity), and weakness of tissues.
- Ehlers-Danlos syndromes are inherited in the genes that are passed from parents to offspring.
- Ehlers-Danlos syndromes symptoms and signs are joints that are more flexible than normal and loose skin that stretches away from the body.
- The diagnosis of Ehlers-Danlos syndrome is based upon the clinical findings of the patient and the family history.
- Ehlers-Danlos syndromes are treated according to the particular manifestations present in a given individual.
What is Ehlers-Danlos syndrome?
Ehlers-Danlos syndromes are a group of disorders which share common
features including easy bruising, joint hypermobility (loose joints),
skin that stretches easily (skin hyperelasticity or laxity), and weakness of tissues.
The Ehlers-Danlos syndromes are inherited in the genes that are passed from parents to offspring. They are categorized according to the form of genetic transmission into different types with many features differing between patients in any given type. The fragile skin and loose joints is often a result of abnormal genes that produce abnormal proteins that confer an inherited frailty of collagen (the normal protein "glue" of our tissues).
In 2001, researchers discovered a new form of Ehlers-Danlos syndrome that is caused by an inherited abnormality in a protein other than collagen that also normally plays a role in binding together the cells of our tissues (including the skin, tendons, muscle, and blood vessels). Abnormalities in this protein, called tenascin, also lead to a form of Ehlers-Danlos syndrome. Researchers suspect that tenascin could play a role in regulating the normal distribution of collagen in the connective tissues of the body.
A bruise is a traumatic injury of the soft tissues that results in breakage of the local capillaries and leakage of red blood cells. In the skin, bruising can be seen as a reddish-purple discoloration that does not blanch when pressed upon. This discoloration leads to the classic "black and blue" appearance. When a bruise fades, it becomes green and brown as the body metabolizes the blood cells and bilirubin pigment in the skin.
What are the types of Ehlers-Danlos syndromes?
(formerly types I & II)
- Marked joint hypermobility, skin hyperextensibility (laxity), and fragility are characteristic of the classic type of Ehlers-Danlos syndrome.
- The smooth, velvety skin is fragile and tears or bruises easily with minor trauma.
- Joint dislocations and scoliosis are common.
- Joint instability can lead to sprains and strains.
- This classical type is inherited as an autosomal dominant genetic trait (directly passed on from one parent to child).
(formerly type III)
- Joint hypermobility is the major manifestation of this form of Ehlers-Danlos syndrome.
- Any joint can be affected, and dislocations are frequent.
- This type is also inherited as an autosomal dominant genetic trait.
(formerly type IV, the arterial form)
In this form of Ehlers-Danlos syndrome, spontaneous rupture of arteries and bowel is a serious manifestation that can lead to death.
- Clubfoot can be present at birth.
- Skin laxity is of varying degrees.
- Veins can be very visible through the skin.
- It is primarily inherited as an autosomal dominant (directly passed on from one parent to child) genetic trait, but recessive (not seen in family members or only in one generation of members of the same family, meaning that an individual must inherit two copies of the mutation, one from each parent) trait inheritance has been described.
(formerly type VI)
- Fragile globe of the eyes, significant skin and joint laxity, and severe curvature of the spine (scoliosis) are typical features.
- Its inheritance pattern is autosomal recessive.
(formerly type VIIB, arthrochalasis multiplex congenita)
- Patients are short in height and severely affected by joint laxity and dislocations.
- Skin involvement is variable.
- Both autosomal dominant and recessive inheritance is possible.
- A skin biopsy can be used to diagnose this disorder.
(formerly type VIIC)
- Patients have severely fragile skin that is soft and doughy with sagging and folding.
- This rare form of Ehlers-Danlos syndrome can be diagnosed with a skin biopsy.
Tenascin-X deficient type
- Joint hypermobility, hyperelastic skin, and fragile tissue are seen.
- Patients with this type lack the multiple shrinking (atrophied) scars in the skin that are often seen in classic Ehlers-Danlos.
- It is inherited as an autosomal recessive genetic trait.
Other rare variant types have been reported in single families.
The term arthritis refers to stiffness in the joints.
What are the signs and symptoms of Ehlers-Danlos syndrome?
Symptoms of Ehlers-Danlos syndromes include
- loose skin that stretches away from the body easily and excessively.
- The skin can appear saggy and soft and may tear easily and be fragile.
Signs of Ehlers-Danlos syndromes include
- easy bruising without significant trauma and joints that can move beyond the normal range of motion.
- Joint hypermobility in Ehlers-Danlos syndromes can lead to multiple joint dislocations.
How do doctors diagnose Ehlers-Danlos syndrome?
The diagnosis of Ehlers-Danlos syndrome is based upon the clinical findings of the patient and the family history. For some types of Ehlers-Danlos syndrome, a skin biopsy to determine the chemical makeup of the connective tissue can help to suggest the diagnosis.
What is the treatment for Ehlers-Danlos syndrome?
Ehlers-Danlos syndromes are treated according to the particular manifestations present in a given individual.
- Skin protection (from injury of trauma and sun, etc.) is critical.
- Wounds must be tended with great care and infections treated and prevented.
- Suturing can be difficult as the skin can be extremely fragile.
Joint injury must be avoided for a person with Ehlers-Danlos syndromes.
- Occasionally, bracing may be necessary to maintain joint stability.
- Exercises that strengthen the muscles that support the joints can help to minimize joint injury. Contact sports and activities involving joint impact should be avoided.
Medically Reviewed on 8/20/2020
Medically reviewed by LaTonya B. Washington, MD; Board Certification in Internal Medicine and Pediatrics
"Clinical manifestations and diagnosis of Ehlers-Danlos syndromes." UpToDate.