Intractable Childhood Epilepsy with Generalized Tonic Clonic Seizures (ICE-GTC) is a more severe disorder than GEFS+. The key feature in ICE-GTC is ‘intractable’ seizures, distinguishing it from the milder GEFS+. Intractable means that seizures are hard to control with anticonvulsant medicines. As a result, a person with ICT-GTC has seizures that are more frequent and severe.

The first seizures usually happen before one year of age, with no known cause other than fever or illness. Seizures that are brought on by fever are called febrile seizures. Tonic clonic seizures are seen most often. These involve a stiffening of the arms and legs (tonic phase) and jerking of the arms, legs, and head (clonic phase). Tonic clonic seizures are also called grand mal seizures.

Myoclonic and absence seizures do not usually occur in ICE-GTC, distinguishing it from the more severe form of epilepsy, Severe Myoclonic Epilepsy of Infancy (SMEI, Dravet syndrome).

Children with the diagnosis of ICE-GTC tend to have mild to moderate learning difficulties. Developmental delays are more significant than the GEFS+ group. Language, communication, and thinking and learning (cognitive) skills may be affected. Behavior problems and delays in social skills can occur in children with ICE-GTC.

Genetic studies show SCN1A mutations in 7 out of 10 ICE-GTC patients. These mutations are usually missense. For general information on gene mutations:

• Home Reference: What Kind of Gene Mutations are Possible?
• See Genetics Section

Summary of ICE-GTC

• Febrile seizures
• Seizures begin in infancy
• Intractable seizures
• Tonic clonic seizures
• Seizures become afebrile
• Poor response to treatment
• Mild to moderate developmental delay
• SCN1A mutations