Watching and Waiting

Learn More About Glut1 DSNot that long ago, Brennan’s father Ryan and I watched helplessly as Brennan struggled to meet developmental milestones. Despite the doctors’ reassurance that “every child develops at their own pace,” my instinct told me that something was wrong. Thankfully, we listened to our intuition.

Brennan was born five weeks early with underdeveloped lungs, and spent the first three days of life in the Neonatal Intensive Care Unit. At 15 months, Brennan had yet to take his first steps so we proceeded to physical therapy. We were relieved when he started walking in time for his 18-month check-up, but soon had a new cause for concern. Brennan began to awkwardly hold his arm behind his back when he walked, like a bird with a broken wing.

Choosing Action

We were done waiting and hoping for the best – something wasn’t right and we were determined to find out what.

With our pediatrician’s guidance, we saw a neurologist who knew within the first two minutes that something was very wrong. Our son had a muscle disorder. “We need to do a lumbar puncture,” the neurologist said. My heart sank – essentially, the doctors didn’t know what exactly Brennan had. To find out, they would place a needle into my son’s spinal canal to extract some of the fluid that surrounds the brain and spinal cord. To this day, I recall how scared and unnerved we were as the doctor spoke.

Thankfully, things came into clearer focus after that day. The lumbar puncture confirmed Brennan had low glucose levels, prompting a genetic test that came back positive for Glut1 Deficiency Syndrome (Glut1 DS). The neurologist explained that Brennan had an extremely rare condition that prevents an adequate amount of glucose from getting to the brain, often causing developmental delays, movement disorders and seizures.

Trusting Your Intuition

“I never, ever lose sight of how lucky we were to reach a diagnosis so quickly. Most families of people with rare diseases are not so fortunate, and often endure about six years of uncertainty and strain.”

The best advice Ryan and I can give to other parents is to be your child’s advocate. Talk to your doctor if something doesn’t seem right, and don’t shy away from difficult questions. Nobody knows your child better than you.

glut1-ds support

Glut1 Deficiency Syndrome (Glut1 DS)

What is it?

Glut 1 DS is rare, genetic disorder that prevents enough glucose (sugar) from getting to the brain, leaving the brain starving for energy.

What causes it?

People with Glut 1 DS have a mutation in a gene that controls the Glut1 transporter, which is the “vehicle” in the body that moves sugar into the brain. The genetic mutation causes the Glut 1 transporter to work improperly.

What are some of the common symptoms?

  • Seizures
  • Delay in speaking
  • Movement disorders
  • Learning difficulties

How many people have it?

Between 3,000 and 7,000 people in the U.S. have Glut1 DS.

Common names for Glut1 DS1

  • De Vivo disease
  • Encephalopathy due to GLUT1 deficiency
  • G1D
  • Glucose transport defect, blood-brain barrier
  • Glucose transporter protein syndrome
  • Glucose transporter type 1 deficiency syndrome

1 GLUT1 deficiency syndrome. National Institutes of Health: Genetics Home Reference Website. Published March 2014. Updated March 19, 2019. Accessed March 29, 2019.

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