What is EDS?

Ehlers-Danlos Syndrome (EDS) is a genetic disorder of the connective tissue. I’m going to explain this in two parts. The ‘genetic’ part means that we are born with it – it is in our DNA. Ehlers-Danlos can be recessive gene or a mutation. If it is a recessive gene, this means that you’ve received the EDS gene from a parent who also has EDS. Individuals with EDS have a 50% chance of passing their EDS gene onto their children. EDS varies in severity, so while a parent may have a milder, slower progressing form of the disease the child may be affected more severely. In the same sense parents that are more severely affected by EDS may have children with very mild EDS – or in the case of the other 50%, a child with no EDS at all. My form of EDS is a mutation – there is nobody else in my family with EDS, though my Mum’s side of the family do have the ‘Gorlin’s sign,’ which means they can touch their nose with their tongue. The Gorlin sign is one of the criteria used to diagnose EDS.

The genes responsible for Ehlers-Danlos Syndrome cause the body to generate faulty or defective collagen, and/or proteins that interact with collagen (If you’re interested, the genes affected can be any of the following: COL3A1, TNXB, COL5A1, COL5A2, COL1A1, PL0D1 (rare), COL1A2 (rare) and ADAMTS2 (rare). There are also several other genes that cause even rarer forms of EDS with only one or two cases ever reported). Diseases or conditions of collagen are called connective tissue disorders. Essentially, collagen is the glue that holds the body together. When my doctors have explained EDS to me, they tell me that people without EDS have collagen like super glue – this holds their body together fairly well. In people with EDS, the collagen is like chewing gum and this becomes weaker over time.

When the collagen performs its job like chewing gum, it doesn’t hold the body together and it causes problems all over the body.

• ·         Joints – dislocations, subluxations (partial dislocations), hyperextensions (stretching really far into positions that normal people can’t manage), osteoarthritis, tendon and muscle tears, scoliosis, and kyphosis (curvatures of the spine) and double joints can all occur. People with EDS tend to have a lot of ‘party tricks’ and this impresses people!
• ·         Cardiovascular – fragile veins and autonomic dysfunction cause heart arrhythmias, low blood pressure, tachycardia (fast heart rate) or bradycardia (low heart rate) and poor circulation. In type 4 Vascular Ehlers-Danlos syndrome and severe forms of all types of EDS, serious ruptures can occur which often prove fatal.
• ·         Skin – typically, a very soft complexion due to the fragile nature of the skin. Skin is much more stretchy in those with EDS. Skin breaks, bruises and scars easily. Skin involvement is the universal feature of type 1 and 2 EDS.
• ·         Gastrointestinal – functional conditions such as IBS are common in those with all types. More severe forms of EDS might manifest dysmotility (slow function or paralysis) or complete gastrointestinal failure. This is due to the GI tract becoming more stretchy, floppy and less able to move food through. Ruptures can also occur in the GI tract, commonly in type four, but also in severe forms of all EDS types. Hernias are also common due to the body’s inability to maintain structure.
• ·         Bladder – incontinence, or bladder paralysis.

Each person is affected by EDS differently. There are many different types of EDS – whilst type 4 is serious and life limiting in all cases, other types of EDS range from mild to life threatening. Milder cases still experience extreme pain and frequent dislocations often requiring surgery, whilst severe cases suffer can cause life threatening complications such as dysfunction of important organs like the heart, GI tract and bladder.

There are 8 main types of Ehlers-Danlos Syndrome, and several other extremely rare forms (only one or two cases of which are documented). Here are the 8 main types of EDS:

• ·         Type 1 and 2 – Classical. Primarily skin involvement. Those with type one experience severe skin involvement whilst type 2 experience moderate skin involvement. All other symptoms of EDS may be experienced from mild to life threatening/limiting, though skin involvement is universal.
• ·         Type 3 – Hypermobility type. Joints are universally involved in this type though not always the most severe feature. All other symptoms may be experienced from mild to life threatening/limiting. This is the most common form of EDS, though it is still quite rare affecting around 1 in 10,000 to 15,000. This is the type of EDS that I suffer from.
• ·         Type 4 – Vascular EDS. Fragility of all major organs as well as the skin and joints. Life limited to around 48 years.
• ·         Type 6 – Kyphoscoliosis. Curvature of the spine, muscle weakness and fragile eyes caused by enzyme deficiency. This is extremely rare with only 60 cases reported.
• ·         Type 7A and B – Athrochalasia. Extremely loose joints and almost constant dislocation of both hips. Also very rare with only 30 reported cases.
• ·         Type 7C – Dermatosparaxis. Characterised by loose, fragile and sagging skin.

Testing for EDS involves genetics (through a blood test) and/or skin biopsy. Characteristics are also examined, such as characteristic facial appearance (type 4 – large eyes, small lips, small chin and sunken cheek bones) and Beighton features (for type 3). The Beighton score looks at how many functions on a set list a patient can carry out. If a patient can carry out three or more functions then an EDS diagnosis is considered likely. If a Beighton score of less than three is achieved, then this does not rule out EDS – other symptoms must be considered. Beighton score looks at the flexibility of a patients fingers, arms and legs, their ability to touch the floor without bending their legs and the Gorlin sign. This features demonstrate flexibility caused by the faulty collagen. People with type three often have ‘marfan’ appearance – a small frame with long slim arms and legs.

There is currently no cure for Ehlers-Danlos syndrome, treatment is to slow down disease progression and eases pain. Physiotherapy, surgery and splinting is usually required for joints and muscles whilst stomas (in the stomach, small bowel, large bowel or bladder), heart pacemakers and stomach pacemakers may be necessary interventions for organ complications. Often wheelchairs are required by the time individuals reach adulthood and in some cases, childhood.

As mentioned throughout this blog post Ehlers-Danlos varies depending on type and severity – sadly, in all types of EDS lives are lost through complication or disease progression but many others with milder forms go on to live longer lives. Symptoms and complications of EDS will vary from one person to the next – nobody has identical genes, and that’s what makes everyone unique, whether they have a genetic illness or not.

I hope this helps you to understand a little more about Ehlers-Danlos Syndrome. I feel the science is quite complicated so I've tried to explain it as best as I can and I've tried to explain any medical jargon I may have used. I am open to questions if anybody should have them. My next blog post is going to look at Ehlers-Danlos Syndrome in pictures – I’ll be showing you all the visual ways in which Ehlers-Danlos Syndrome affects me.