We may have seen on occasion how someone could stretch their skin to unusual limits, or how some people are able to make twists with different parts of their body that escape most people because they have hyperlaxity.

In most of these cases we see it as a curiosity, and the truth is that about 10% of the population presents this characteristic without having any major problem.

However, there is a much more severe problem that sometimes shares some characteristics with hyperlaxed people, except that in their case it appears along with other symptoms that are detrimental to their quality of life and may even be dangerous for their survival. This is the Ehlers-Danlos syndrome , a strange and unusual genetic disease that we will talk about throughout this article.

What is Ehlers-Danlos syndrome?

It is called Ehlers-Danlos syndrome, a strange and unusual syndrome, of genetic origin, which is characterized by the presence of alterations in the connective tissue and specifically by deficits in the production of collagen . These deficits, which are produced at a generalised level throughout the body, are translated into an affectation at the level of the skin, joints, blood vessels or even organs. It is a disease mainly observed in humans, although some cases have also been seen in other animals.

Although there is a great heterogeneity, among the main and most notorious symptoms of this disorder we can find the presence of hyperlaxity in the joints and ligaments, hyperelasticity of the skin and ecchymosis (lesions in which there are hemorrhages within the skin, such as those produced by a blow), as well as muscle weakness and fragility in the tissues: it is not uncommon for bruises to appear at the slightest blow, pain in the joints, or for dislocations and dislocations to appear easily.

In some cases it can be linked to arthritis, respiratory and vision problems . In severe cases, it can lead to rupture of internal organs, heart problems or deformities, as well as chronic pain or molluscum tumors.

Ehlers-Danlos syndrome is a very rare disease, suffered by only 1 in 5000 people, and seems to occur in higher proportion in women and children. It is common for this problem to arise in a comorbid way with other problems such as chronic fatigue, tendinitis, hearing loss, fibromyalgia or scoliosis. In some cases it is confused with celiac disease or even abuse. As the subjects grow up, the hyperlaxity tends to decrease, but the pain and complications derived from it remain .

It is a syndrome whose variety can vary from a mild problem to, and especially in some subtypes, can have fatal repercussions. This is especially relevant in cases with vascular or organ problems , in which there may be ruptures of blood vessels or the walls of the intestines or the uterus (in this case pregnancy and childbirth may be particularly delicate).

Although in most cases life expectancy is normal and there is no decrease, the symptoms and their possible complications can harm and diminish the quality of life.

Main types

Ehlers-Danlos syndrome is not a homogeneous disorder, but rather presents a high degree of heterogeneity. In fact, rather than a single disorder we could speak of a group of them , with different typologies.

Although the existence of up to thirteen variants was formerly considered, the types of syndrome were later reclassified and reduced to a total of six (being lost or integrated into others such as fragile cornea, spondylic-spondylochial dysplasia, muscular-contractual, periodontitis type or that generated by tenascin-X deficit), which are presented below.

1. Classic type

The so-called classic type is the most common of all the variants of the syndrome, and is characterized by hypermobility of the joints and hyperelasticity and extensibility of the skin , together with the fragility of these tissues. It is common for the fingers to be completely bent and for dislocations, dislocations and sprains to occur, and for benign neoplasms to occur.

Small injuries often result in large bruises , and events such as pregnancy can be dangerous. Mitral insufficiencies may appear as a result of deformations in the heart valves, in addition to frequent hernias in different points of the digestive tract.

2. Hypermobile type

This is the second most common type, and in this case we observe hyperelasticity and mobility of joints (which dislocate easily) especially in areas such as arms and legs, as well as frequent pain and hypersensitivity to it. Unlike the previous type, skin or tissue fragility is not so common .

3. Vascular type

Probably the most serious and dangerous of all the subtypes, although fortunately less frequent than the anteriors, is the Ehlers-Danlos syndrome vascular type.

In this type the skin is not elastic and there is no hyperlaxity in the joints (except perhaps in the fingers), but both this and other tissues are thin and fragile (it is not uncommon to be able to see the veins through the skin). Especially and as can be guessed from the name it highlights the fragility of the arteries and other blood vessels as well as the organs , which causes a great facility for lacerations and rupture.

This is the most lethal of all subtypes and the only one that reduces life expectancy, with the cause of death usually being ruptured veins and arteries of the intestines or uterus (again, the risk during pregnancy is high).

4. Kypho-scholastic type

A very rare subtype (in which there are hardly any diagnosed cases) which presents characteristics similar to the classic one, with the added feature of the presence of a congenital scoliosis that gets worse over time.

Increased muscle weakness, osteopenia, and possibly psychomotor retardation are common. In some cases, the ability to walk may be lost.

It can lead to symptoms typical of Marfan syndrome, from typical morphology (extremely long limbs) including the risk of involvement of the aortic artery. They may also have visual problems, including a ruptured eyeball, although this is not as common.

5. Arthrocalasic type

Another unusual subtype is characterized by hyperlaxity in the joints, osteopenia and, as a rule, the presence of congenital or frequent dislocations in both hips . There also tends to be hypotonia.

6. Dermatosurgical type

Possibly the least common and with hardly any recognized cases , this subtype is characterized by skin fragility and laxity, with frequent herniations and loss of elasticity. It is very common to suffer from hematomas.

What are its causes?

Ehlers-Danlos syndrome is, as we have said, a disorder, or rather a group of disorders, of genetic origin . Thus, the problems in the synthesis of collagen that generate most of the above-mentioned symptoms derive from the presence of mutations in different genes in the organism.

Some of the genes whose mutations have been associated with this type of syndrome are COL5A1, COL5A2, ADAMTS2, COL1A1, COL1A2, PLOD2 or TNXB. However, in some cases it is not known what genetic alterations may be producing the problem.

Although there are cases of de novo in people without a family history, the findings seem to indicate that in many cases we are dealing with an inherited disorder . In the most common subtypes, inheritance is autosomal dominant (especially in the classic or hypermobile types), while in the less frequent ones, inheritance is autosomal recessive (something that occurs in the dermatosparaxis type or in the vascular or kyphoscoliosis types).

Treatment of this syndrome

Ehlers-Danlos syndrome is a disorder of genetic origin that does not have a curative treatment, being the existing treatments those directed to correct or palliate the symptoms and alterations that it generates .

Each specific case will require a specific and specialized treatment. For example, occupational therapy or physiotherapy can be performed to improve motor difficulties or psychomotor delays , or surgery can be used to correct heart problems, drain bleeding, install prostheses or braces or remove tumours.

Furthermore, it should be taken into account that both patients and their environment may present psychological problems such as anxiety, depression, self-esteem problems and difficulties in different areas of their day-to-day life. In this sense, psychoeducation and the application of different psychological therapies may be useful, depending on the case.

Bibliographic references:

  • Beighton, P., De Paepe, A., Steinmann, B., Tsipouras, P., Wenstrup, R.J. (1998). Ehlers-Danlos syndromes: revised nosology, Villefranche, 1997. Ehlers-Danlos National Foundation (USA) and Ehlers-Danlos Support Group (UK). Am J Med Genet 77 (1): 31-7.
  • Genetic and Rare Diseases Information Center (2017). Ehlers-Danlos syndrome. National Center for Advancing Translational Sciences. [Online]. Available at: https://rarediseases.info.nih.gov/espanol/12323/sindrome-de-ehlers-danlos#diseaseCausaSection
  • Krakow, D. (2017). Heritable diseases of connective tissue. In: Firestein GS, Budd RC, Gabriel SE, McInnes IB, O$0027Dell JR, eds. Kelly and Firestein$0027s Textbook of Rheumatology. 10th ed. Philadelphia.
  • Puerto Martínez, M. (2017). Clinical characterization and management of Ehlers Danlos Syndrome. Journal of Medical Sciences of Pinar del Río, 21 (4).
  • Steinman, B., Royce, P.M. and Superti-Furga, A. (2002). The Ehlers Danlos Syndrome. Connective Tissue and Its Heritable Disorders. pp. 431-523. Wiley-Liss, In.