Washington Post
In 1970, a Japanese pediatric neurologist named Masaya Segawa examined two girls. The girls were cousins and they seemed to be suffering from the same puzzling ailment: a contraction of the muscles that caused their limbs to twist uncontrollably, a condition known as dystonia. Six years later, Segawa encountered a 51-year-old woman who had been experiencing the same symptoms since the age of 8.
Segawa discovered that in all three cases the symptoms could be controlled by small doses of L-dopa, which the body converts into the neurotransmitter dopamine. The disorder goes by the name dopa-responsive dystonia but it's also known as Segawa's disease, after that observant Japanese doctor, one of the grand old men of pediatric neurology. It affects girls three to four times more frequently than boys. In 1993, researchers were able to find the gene that causes the abnormality, mapping it to chromosome 14q.
In 2003, Morgan Campagna was an 8-year-old girl living in Guantanamo Bay, Cuba, with her mother, Christie, and sister, Ashlyn. From the age of 4, Morgan had been experiencing strange symptoms, including a limp that worsened as the day progressed. Odder still, Morgan would draw her arms up to her chest, her hands twisting in on themselves.
"Doctors would tell me she was going to grow out of it, but nobody would tell me what 'it' was," her mother said.
A Navy doctor visiting the base decided this was not something Morgan was going to grow out of. The doctor arranged for Morgan to be seen by Mark Batshaw at Children's National Medical Center in Washington and his colleague Bennett Lavenstein.
"Dr. Batshaw invited me to see her and asked what I thought of her gait," said Lavenstein, a pediatric neurologist. "We put our heads together and, quite frankly, I thought L-dopa."
Dopamine has a lot of roles in the nervous system. With Segawa's disease, Lavenstein said, "we're focusing on predominantly dopamine in the basal ganglia of the brain, which is inherently responsible for controlling smooth, graded motions, as opposed to concentrations elsewhere, which may relate to attention deficit disorder, schizophrenia or the pleasure centers."
Because of an enzymatic deficiency, Segawa's patients are unable to synthesize dopamine properly, unable to control some of their muscles. The disease is similar to Parkinson's disease, without that ailment's inevitable downward spiral.
Morgan underwent a battery of tests -- liver function, amino acids, copper metabolism -- but her doctors at Children's were pretty sure they knew the answer. The correct diagnosis would be confirmed by the treatment. They started Morgan on a twice-a-day regimen of Sinemet, a pill used to treat Parkinson's. Within a week, her symptoms were almost gone.
Morgan is 16 now. Her family lives in Manassas. She likes science, likes to read, likes to draw her own comic books. She goes on walks without tiring easily, as she once did. She marvels at the fact she was once unable to control her body, remembering how strange it was to look down and find her hands up near her chin when she'd never intended to move them there.
"When I was little, I just thought I was normal," Morgan told me recently. "I didn't really know what normal was."
Segawa discovered that in all three cases the symptoms could be controlled by small doses of L-dopa, which the body converts into the neurotransmitter dopamine. The disorder goes by the name dopa-responsive dystonia but it's also known as Segawa's disease, after that observant Japanese doctor, one of the grand old men of pediatric neurology. It affects girls three to four times more frequently than boys. In 1993, researchers were able to find the gene that causes the abnormality, mapping it to chromosome 14q.
In 2003, Morgan Campagna was an 8-year-old girl living in Guantanamo Bay, Cuba, with her mother, Christie, and sister, Ashlyn. From the age of 4, Morgan had been experiencing strange symptoms, including a limp that worsened as the day progressed. Odder still, Morgan would draw her arms up to her chest, her hands twisting in on themselves.
"Doctors would tell me she was going to grow out of it, but nobody would tell me what 'it' was," her mother said.
A Navy doctor visiting the base decided this was not something Morgan was going to grow out of. The doctor arranged for Morgan to be seen by Mark Batshaw at Children's National Medical Center in Washington and his colleague Bennett Lavenstein.
"Dr. Batshaw invited me to see her and asked what I thought of her gait," said Lavenstein, a pediatric neurologist. "We put our heads together and, quite frankly, I thought L-dopa."
Dopamine has a lot of roles in the nervous system. With Segawa's disease, Lavenstein said, "we're focusing on predominantly dopamine in the basal ganglia of the brain, which is inherently responsible for controlling smooth, graded motions, as opposed to concentrations elsewhere, which may relate to attention deficit disorder, schizophrenia or the pleasure centers."
Because of an enzymatic deficiency, Segawa's patients are unable to synthesize dopamine properly, unable to control some of their muscles. The disease is similar to Parkinson's disease, without that ailment's inevitable downward spiral.
Morgan underwent a battery of tests -- liver function, amino acids, copper metabolism -- but her doctors at Children's were pretty sure they knew the answer. The correct diagnosis would be confirmed by the treatment. They started Morgan on a twice-a-day regimen of Sinemet, a pill used to treat Parkinson's. Within a week, her symptoms were almost gone.
Morgan is 16 now. Her family lives in Manassas. She likes science, likes to read, likes to draw her own comic books. She goes on walks without tiring easily, as she once did. She marvels at the fact she was once unable to control her body, remembering how strange it was to look down and find her hands up near her chin when she'd never intended to move them there.
"When I was little, I just thought I was normal," Morgan told me recently. "I didn't really know what normal was."
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