What Was Causing Little Kelly’s Uncontrollable Muscle Spasms?
The child's debilitating symptoms were a medical mystery, until a doctor discovered a genetic mutation so rare as to be unheard of.
What’s Wrong With Me?
The patient: Kelly (name has been changed), a nine-year-old girl
The symptoms: Uncontrollable muscle contractions
The doctor: Dr. Mary King, pediatric neurologist at Temple Street Children’s University Hospital in Dublin, Ireland
Kelly was a bright, busy toddler. But in 2011, when one of the then 18-month-old’s feet began to turn inwards, her parents became alarmed enough to consult a doctor, especially as the condition slowly spread. Over the next couple of years, both Kelly’s legs twisted painfully and she needed support to walk. When the muscle contractions spread to her hands, they tightened into fists and she could no longer pick up her toys or hold a spoon.
Throughout that time, specialists in England, where the family lived, had few answers. They told Kelly’s parents she had dystonia, which meant her muscles were continually going into spasms, but they couldn’t pinpoint the cause. Repeated brain scans, lumbar punctures, blood tests, urine tests and genetic tests all came back normal, and yet Kelly was clearly getting worse.
Progressive dystonia is practically unheard of in a healthy child. It can be caused by a physical abnormality in the part of the brain that controls movements, but the tests ruled that out. Meanwhile, drugs that often help dystonia symptoms, such as levodopa and baclofen, did nothing; all Kelly’s medical team could do was treat her discomfort with painkillers and muscle relaxants. By age four, Kelly’s condition had spread to her neck and facial muscles, and she could no longer speak.
A Closer Look at Kelly’s Genes
Dr. Mary King works with Irish patients who have very rare genetic diseases. Since Kelly has Irish heritage and was coming to Dublin to visit relatives, King was consulted on the case. She decided to analyze the child’s genome as part of a Genomics Medicine Ireland project she was involved in, which aims to get insights for better treatments by studying people’s genetic material. King enrolled Kelly and had her blood drawn. An analysis was ready within a few months. It was King’s colleague who spotted the anomaly in Kelly’s profile—she had a mutation in a gene known as KMT2B. “When I looked at it, I knew that was probably the answer,” says King. The mutation, which is not inherited, had been identified by other researchers less than a year earlier, and had been shown to cause progressive dystonia.
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Risky Treatment
Even better news for Kelly was that a number of patients with the same genetic mutation had responded well to deep brain stimulation (DBS). In this surgical procedure, electrodes are implanted into the brain to stimulate neurons that aren’t firing normally. “It’s like a pacemaker. It’s almost a rebooting of the neuro surface of the brain,” King explains. DBS isn’t typically tried with children, but it was Kelly’s best chance for recovery. King immediately called Kelly’s doctors in England—and was shocked to learn the young patient was in the hospital’s intensive care unit in a state of constant severe muscle contractions. She was being fed through a tube in her stomach and using a ventilator to breathe. “Her parents were desperate, wondering if she was going to survive,” says King. Without a moment to lose, the British team put her into surgery for DBS.
In the days following the procedure, the change in Kelly was dramatic. “Within a couple of weeks, she was out of bed, sitting up,” says King. The positive progress continued as Kelly’s brain cells formed reconnections and she gradually regained her ability to move. In November of 2017, Kelly said her first word in four years: “Mama.” Today, Kelly can eat and ride a tricycle. The nine-year-old has regular physiotherapy and it may take up to two years to see the maximum benefits of DBS, but her doctors hope she’ll have few, if any, symptoms by then. There’s no question the high-tech surgery has rescued the future of this lively little girl.
Next, read the incredible story of how a mother and son’s mysterious health issues turned out to be connected.
