ABOUT STXBP1

SYMPTOMS

Symptoms usually occur in infancy but may begin in childhood or early adulthood. These may change over time.

 

Intellectual Disability:

Moderate to severe, which may be accompanied with behavioural problems such dysregulation and features of autism

 

Seizures:

(there may be more than one type)

  • Absence (staring spells, or petit mal)

  • Myoclonic (quick muscle jerks, outside of sleep)

  • Tonic-clonic (whole body stiffening with rhythmic jerks)

  • Infantile spasm (a few second contraction of the whole body)

  • And others

 

Movement Disorders:

  • Tremor (fine shaking)

  • Ataxia (difficulty with balance and coordinating movements, including walking)

  • Dystonia (abnormal posturing)

  • Bruxism (teeth grinding)

  • Hyptonia (loose muscle tone)

MECHANISM

STXBP1 is involved with the release of neurotransmitters in neurons. Specifically it assists with the binding of vesicles (filled with neurotransmitters) to a neuron's cell membrane for release.

This dysfunction of neurotransmitter release can cause a wide range of symptoms and disorders.

CURRENT TREATMENT

 

Anti-seizure Medication:

Choice depends on the types of seizures, potential side effects and experience of the treating neurologist. Levetiracetam, or a related medication, may be a reasonable first choice as it works in the pathway where the functional problem is. Infantile spasms are treated differently from other seizure types. A “rescue” medication, usually a benzodiazepine, is often provided to use in case of a prolonged seizure. Rarely, drug-resistant seizures may be treated with neurosurgery.

 

Development:

Assessment and therapy are important to maximize the developmental potential. This may include: speech therapy, occupational therapy, and speech-language therapy. Psychology may be involved for behaviour and cognitive evaluation.

 

Specialists:

In addition to developing a good relationship with one’s family physician and paediatrician, one is often followed regularly by a neurologist (adult or paediatric). Other specialists who may consult include: geneticists, developmental paediatricians, psychiatrists, gastroenterologists, orthopaedic surgeons, and neurosurgeons. Most people will have had a MRI of their brain, which is best evaluated by a neuroradiologist.