What is Classical EDS?
Classical EDS is a type of EDS, often caused by faulty collagen V.
Classical EDS can be very variable even within the same family. It is a rare condition and therefore many health professionals will not have seen someone with this diagnosis. Classical EDS was previously known as EDS types I and II.
What are the main symptoms and signs of Classical EDS?
Individuals with Classical EDS may have the following features:
What causes Classical EDS?
Classical EDS is a genetic condition caused by an alteration, also known as a mutation, in a gene. Some individuals with Classical EDS have an alteration in either the COL5A1 or COL5A2 genes. These genes are the instructions for making collagen type V. When either gene is altered it causes a lack or deficiency of this collagen. This leads to disordered packing of collagen fibres making the connective tissue less effective, particularly in the skin and joints.
In other individuals with Classical EDS the genetic cause for their condition is not yet known.
How is Classical EDS inherited?
Our bodies are made up of millions of cells and inside almost every cell is a complete set of our genetic material. Genes are the unique instructions which make us each individual. There are many thousands of genes, each carrying a different instruction. We have two copies of each gene. One copy of each pair is inherited from our mother, in the egg, and the other from our father, in the sperm.
An individual with Classical EDS will have an alteration in one copy of a particular gene (sometimes COL5A1 or COL5A2). Classical EDS runs in families following a pattern called autosomal dominant inheritance, because the altered copy of the gene is dominant over the other copy. Autosomal means it can affect, and be passed on by, both males and females. When someone with this condition has children they will pass on one copy of the gene associated with Classical EDS to their child, either the altered or unaltered copy. So in each pregnancy, there is a 50% (1 in 2) chance of a child inheriting the altered copy of the gene and having Classical EDS.
Equally, there is a 50% (1 in 2) chance of a child getting the unaltered copy of the gene and not inheriting the condition. The gene alteration can happen for the first time in an individual, so there may be no previously affected family members.
How can family members find out if this is relevant to them?
If family members would like further information about the implications for them, they should talk to their GP about the possibility of being referred to their local genetics service.
What management is recommended for people with Classical EDS?
Individuals should have an echocardiogram (ultrasound scan) of their heart. If anything unusual is found, treatment may be recommended by the heart specialist.
Careful repair of wounds may help to avoid excessive scarring. Protective clothing may help minimise damage to high risk areas of the body, such as shins. This may be particularly useful for children.
If surgery is being considered, the surgeon must be aware of the diagnosis of Classical EDS because of tissue fragility and they may wish to seek further advice.
Is there anything an individual with Classical EDS should avoid doing?
It is recommended that people with Classical EDS avoid contact sports, such as rugby, football, martial arts or boxing, to minimise the possibility of skin splitting and damage to joint ligaments. However, it is important to maintain a healthy lifestyle so gentle exercise, such as walking, cycling or swimming may be beneficial.
What advice is given to both men and women with Classical EDS who are considering a pregnancy?
Before planning a family it may be helpful to discuss the implications of pregnancy with your family doctor (GP) who can refer you to your local genetics department. The geneticist or genetic counsellor will discuss the options available to you. It is important that the obstetrician and midwives are made aware of the diagnosis of Classical EDS during a pregnancy. Additional care will be needed during delivery of the baby as women with Classical EDS have a higher risk of vaginal and perineal tearing at delivery.
There is an increased risk of early rupture of membranes and premature delivery if either parent has Classical EDS. This is because the membranes surrounding the baby can be weak or fragile.