What Are Ehlers Danlos Syndromes?

Introduction to Ehlers-Danlos Syndromes (EDS)

Ehlers-Danlos Syndromes (EDS) are a group of connective tissue disorders.¹ Your connective tissues connect, adhere, and support the other structures and tissues that make up your body. EDS can affect any of the connective tissues in your body including your cartilage, bone, blood, and fat.² The EDS are all genetic disorders – they are caused by mutations in the genes that are associated with collagen production.¹ Collagen is an important component of your connective tissue. Collagen has a tough, fibrous structure with gives connective tissues strength.² In EDS, the mutated genes cause weak collagen to be produced or a decrease in the amount of normal collagen in the connective tissue – which leads to the three hallmarks of the disease; skin hyperextensibility (very stretchy, elastic skin); joint hypermobility (very flexible joints), and tissue fragility (easily damaged skin and blood vessels).¹ EDS was first named in 1946. Since then, the EDS has been categorised into 13 different subtypes.³ EDS are rare, it is estimated that, in the general population, 1 in 5000 people have the condition diagnosed.¹ This article will explain the classification, causes, symptoms, diagnosis, and treatment of EDS.  

What are the Subtypes of Ehlers-Danlos Syndromes?

EDS is classified into 13 different subtypes based on symptoms and clinical features. The five most common subtypes are:⁴

• Classical EDS
• Classical-like EDS
• Cardiac-valvular EDS
• Vascular EDS
• Hypermobile EDS

 The less common subtypes are:⁵

• Arthrochalasia EDS
• Dermatosparaxis EDS
• Kyphoscoliotic EDS
• Brittle Cornea Syndrome
• Spondylodysplastic EDS
• Musculocontractural EDS
• Myopathic EDS
• Periodontal EDS

EDS describes a group of conditions (the 13 subtypes) that each have a unique set of symptoms. If you have an EDS, getting an accurate diagnosis is important for your ongoing care – it indicates to clinicians how the condition will progress, and what treatments will be most effective.  

What Causes Ehlers-Danlos Syndromes?

EDS is a genetic condition – it is caused by changes in your DNA sequence (genetic mutations) that occur when your cells make copies of themselves for growth/repair. For EDS, the genetic mutations occur in the DNA sequences that encode the information that allows your cells to produce collagen. There are around 20 known genetic mutations that cause EDS, however, there are still some cases where the specific causal mutation cannot be identified.¹  

What are the Symptoms and Complications of Ehlers-Danlos Syndromes?

Each EDS subtype has its own set of symptoms. If you are diagnosed with an EDS, your healthcare provider will discuss the subtype-specific symptoms with you. Some of the common symptoms include:³

Skin-related Symptoms

• Softer, thinner, or more stretchy skin
• Skin that bruises easily
• Slow wound healing

Joint Symptoms

• Overly flexible
• Unstable joints
• Dislocations
• Joint pain

Cardiac Symptoms

• Fast heartbeat (tachycardia)
• Cardiac valve collapse

Gastrointestinal Symptoms

• Abdominal pain
• Bloating
• Nausea and vomiting
• Reflux symptoms
• Diarrhoea
• Constipation

Gynaecological Symptoms

• Infertility
• Pregnancy complications

Other Symptoms

• Headaches
• Fatigue
• Difficulty concentrating
• Eye problems

It is important that if you do have an EDS diagnosis to keep updating your healthcare team on the severity of your symptoms. Your healthcare team can then make sure that they have the right treatment interventions in place to ensure you maintain a high quality of life.

How are Ehlers-Danlos Syndromes Diagnosed?

The diagnosis of EDS can be a long process. The process usually begins when a clinician notices a patient returning to the clinic with symptoms consistent with EDS. A full medical history and physical examination will then be performed. If it seems likely that EDS is the correct diagnosis, clinicians will identify which areas of the body are affected and complete a full symptom analysis. The outcomes of this will indicate which EDS subtype should be given as the final diagnosis.⁴

In addition, a referral for a CT, MRI and/ or ECG may be recommended to rule out any cardiovascular concerns that can be associated with EDS. For confirmation of a subtype diagnosis, a referral for a genetic test may be given. A genetic test can show which genetic mutation is causing the EDS symptoms.⁴

Many conditions have overlapping symptoms, which can lead to patients receiving an initial misdiagnosis. For EDS, the characteristics of osteogenesis imperfecta, Marfan syndrome, Loeys-Deitz syndrome, and cutis laxa may all be investigated as possible diagnoses. Although most of these alternative diagnoses will be ruled out early in the diagnostic process, it is important that if you do have a diagnosis of any of these conditions( including EDS) tocontinue to discuss your symptoms with your doctor. It means that you can receive the most effective treatments, but also ensures that you have the correct diagnosis.⁴

How are Ehlers-Danlos Syndromes Treated?

There is no cure for EDS. Treatment and management techniques are focused on the prevention of disease progression and complications. Due to the complex nature of the symptoms caused by EDS, the treatment of the condition usually involves a number of different medical professionals from different specialities. For example, joint-related symptoms will be treated by an orthopaedist and cardiac symptoms treated by a cardiologist.⁴

 The prevention strategies recommended for EDS are:⁴

• Screening for heart abnormalities
• Limiting high-risk sports (such as contact sports)
• Prescribing physical therapy

If you have EDS and are worried about passing on the genetic mutation to your biological children, genetic testing can provide some answers. If you are pregnant and have EDS, the pregnancy will be treated as high risk due to the complications that can occur to you or your baby during labour.⁴

If you are worried about symptoms or the impact of the condition on your life overall, it is important that you contact your healthcare team. They will be able to improve your treatment plan, refer you to the relevant medical specialist, and offer psychological support or mental health care.⁴

What is the Prognosis for Ehlers-Danlos Syndrome?

Each subtype of EDS comes with different disease severity, progression, and potential complications. For some subtypes, hypermobile EDS and classic EDS, there is not considered to be a lower life expectancy. However, for vascular EDS there is a high risk of a major vascular event by the age of 40 and a resulting lower life expectancy.⁴  

There are, however, many long-term health considerations for patients with EDS - these include restrictions on activities that increase the risk of injury, medications, and medical appointments that can become overwhelming. The psychological impact of conditions like EDS, where there is no cure, can be substantial. Many services can help – if you do feel overwhelmed, speak to your healthcare team as they can direct you to patient support groups, or mental health services.

Summary

EDS are a group of conditions that are caused by genetic mutations that affect a cell's ability to produce collagen. There are many different symptoms associated with EDS, however, they are all characterised by skin abnormalities, hypermobile joints, and fragile body tissues. There is no cure for EDS. A multidisciplinary healthcare team will work together to support you in symptom management. The success of disease management depends on the subtype of EDS (some subtypes have more complex symptoms than others), and on a patient’s ability to keep up with the physiotherapy, medications, and other treatment strategies. EDS and the treatment of it can become overwhelming for patients, it is important to remember that physical and mental support is available from your healthcare provider.