Glut1 Deficiency is a rare genetic condition that affects brain metabolism. It is caused by a mutation in the SLC2A1 gene, which regulates the glucose transporter protein type 1 (Glut1). Glut1 is the principal transporter of glucose, the primary source of energy, across the blood-brain barrier. More than 100 different types of mutations and deletions of this gene have been found to date in Glut1 Deficiency patients.
Impaired glucose transport associated with Glut1 Deficiency creates an energy crisis in the brain and often results in seizures, movement disorders, and developmental delays. The standard of care treatment is a ketogenic diet. This low carbohydrate, moderate protein, high fat diet causes the body to produce ketones, which are used as an energy source by the brain and other tissues when glucose is limited. The diet helps most patients with most symptoms and helps preserve brain growth and development, so early diagnosis and treatment is critical.
Could it be Glut1 Deficiency?
The hallmark symptoms of Glut1 Deficiency are seizures (90% of patients), a complex movement disorder, developmental delay, and speech/language disorders. There is a great deal of variance across a wide spectrum in both the combination and severity of symptoms from one patient to another, and symptoms may evolve over time.
Some of the other suggestive symptoms seen in many Glut1 Deficiency patients:
- paroxysmal exercise-induced dystonia/dyskinesia (PED)
- early onset absence seizures before the age of 3
- treatment resistant seizures/epilepsy at any age
- fluctuation of symptoms with hunger, fatigue, heat, illness, anxiety, excitement
- symptoms worse just after waking in the morning
- symptom improvement after eating
- opsoclonus-like eye movements (aberrant gaze saccades)
- paroxysmal neurological symptoms
(seizures, movement disturbances, headaches, energy levels, confusion, mood)
Other conditions sometimes diagnosed in patients with Glut1 Deficiency:
- cerebral palsy
- hemolytic anemia
- alternating hemiplegia of childhood