Children struck down by a devastating muscle disorder are walking again after doctors discovered how to diagnose and treat their condition.
About 70,000 people in Britain suffer from dystonia, a genetic condition which causes a wide range of disabling symptoms, including painful muscle spasms and abnormal postures, and can affect walking and speech.The disorder leaves many youngsters struggling to walk, feed and dress themselves and symptoms gets steadily worse over time.
However, the condition is difficult to diagnose, particularly in children, and sufferers are often wrongly labelled as having cerebral palsy, Huntington’s or Parkinson’s disease, meaning they get the wrong treatment.
But now scientists have discovered that sufferers carry a specific gene mutation, so for the first time it is possible to diagnose the condition, and also treat it, using deep brain stimulation – a therapy which targets the part of the brain responsible for spasms.
“Through DNA sequencing, we have identified a new genetic movement disorder that can be treated with deep brain stimulation,” said Dr Manju Kurian, paediatric neurologist at Great Ormond Street Hospital and researcher at UCL Institute of Child Health.
“This can dramatically improve the lives of children with the condition and enable them to have a wider range of movement with long-lasting effects.”
It means that children like 12-year-old Katie Alexander, from Cornwall, finally have hope.
Katie’s mother Sarah first noticed there was something wrong when her daughter kept falling over at just two years old. By the time she reached five, she had begun toppling backwards while standing.
Specialists initially diagnosed dyspraxia, and then said it could be a host of other conditions, including Wilson’s disease and cerebral palsy. But after 10 years of searching for an answer, doctors finally diagnosed dystonia this year.
Researchers at University College London, who were looking for a genetic reason behind the illness, found a tiny abnormality in Katie’s DNA which allowed them to cross-check it with 18 others suffering the disease. They found that all the patients carried a mutation of the KMT2B gene.
Katie, who uses a wheelchair and struggles to control her muscles below her neck, will undergo deep brain stimulation in May which could allow her to walk again unaided.
“Even if she could just sit up by herself, it would be wonderful,” said Mrs Alexander, 45. “The not knowing was the worse part of it all. We didn’t know what it was. I used to look at Katie when she was sleeping at night and think, ‘Are you dying?’
“She was my first child so I always worried if I had done something wrong. Was I feeding her correctly? So it’s such a relief knowing that it is not something that we did to her.
“She can only walk about five to 10 steps unaided and it isn’t really safe for her to do that. We have to do everything for her and, at the moment, she doesn’t mind but she is getting to an age where she won’t want that much longer, so we are hopeful that this treatment will work. “
The teams at Great Ormond Street and UCL have been carrying deep brain stimulation for several years and have seen astonishing results. The treatment either restored or significantly improved walking and hand and arm movement.
“Many patients did not show any response to the usual medications that we use for dystonia, so we knew we would have to consider other strategies,” added Dr Kurian.
“We know, from our experience with other patients with dystonia, that deep brain stimulation might improve our patients’ symptoms, so were keen to see what response patients would have to this type of treatment.
“Remarkably, nearly all patients who had deep brain stimulation showed considerable improvements. One patient was able to walk independently within two weeks; in five patients, the improvement has lasted for more than three years. It is an astounding result.”