EAST Syndrome is a disorder that affects several organs in the body. The name EAST refers to Epilepsy (fits or seizures), Ataxia (impaired movement coordination), Sensorineural deafness (a specific kind of hearing impairment) and Tubulopathy (a kidney problem that affects salt levels in the body).
A diagnosis of EAST Syndrome is made by the combination of all these problems. The severity of symptoms can vary between individuals. Seizures typically start in the first year of life. The movement disorder is typically noted because of delayed childhood development. In ataxia a person’s movements are wobbly and poorly coordinated and often associated with weakness. Blood tests usually show a low concentration of potassium and magnesium and a raised level of bicarbonate plasma (hypokalaemic alkalosis). These features are permanent unless treated. The EAST diagnosis can be confirmed by a genetic test.
The first step is to make the correct diagnosis. EAST Syndrome was only described for the first time in 2009.
There is no current treatment that can cure the condition. However, doctors can improve many of the symptoms:
- Seizures can be treated with anti-epileptic medications. This is usually done under the care of a Neurologist.
- Deafness can be improved with hearing aids. Getting the right prescription requires an audiologist.
- Kidney problems can be helped by providing extra salts, especially potassium and magnesium supplements. Some dietary advice is also needed. Children will require the care of a paediatric nephrologist.
- Child development specialists will coordinate supportive treatments such as physiotherapy.
EAST Syndrome is a life-long condition. Patients need to stay on treatment and have regular hospital appointments and blood tests. The amount of supplements and medicines are likely to change over time.
EAST Syndrome can affect boys and girls equally. It is caused by changes (mutations) in a gene called KCNJ10 that is important for normal brain, ear and kidney function.
Everyone has 2 copies of KCNJ10:
- Healthy people have two normal copies
- Carriers have one copy that works normally and one that doesn’t. Carriers are usually perfectly healthy because the normal copy can still do its job.
- In patients with the condition, neither copy works normally. The gene can’t do its job properly so problems develop.
EAST Syndrome can be passed from parents to children depending on their genes. If both parents are carriers, then there is a 1 in 4 (25%) chance that their child will inherit both copies of the abnormal gene and have the condition. If these parents have an unaffected child there is a 2 out of 3 chance that that individual will be a carrier of the abnormal gene.
The diagram below shows how this works.
A= gene without mutation a = gene with mutation
The unique combination of symptoms should make a diagnosis of EAST Syndrome easily recognizable as long as clinicians know about it. A DNA test may help to confirm the diagnosis. This is a simple blood test that looks at the genes that cause the condition. Some people find this information helpful when planning a family, to see whether their partner is a carrier. Other relatives might also want their DNA examined. This can be arranged through their doctor, a renal clinic, or a geneticist. (Visit the Clinicians page for more information on EAST Syndrome).
The Tubulopathy Rare Disease Group (RDG) is working with international partners with the aim of finding new and improved treatments and to empower patients. A first step is to compare the symptoms and genetic markers of EAST, Gitelman and the various Bartter Syndromes. To do this the RDG is registering patients with these conditions in the National Renal Rare Disease Registry (RaDaR). The registry will be used to find suitable participants for future research trials into the effectiveness of new treatments.
If you are interested in finding out more about RaDaR or the activity of the RDG please visit the Tubulopathy RDG page which covers EAST, Bartter and Gitelman syndromes.