Epilepsy is a group of disorders in which there are recurrent episodes of altered cerebral function associated with a seizure. The clinical manifestation of these seizures varies in effect from brief lapses of awareness to prolonged bouts of unconsciousness, lim jerking and incontinence.
There is no clear cause of seizures in many cases. However, in up to 40% of people with epilepsy there is a family history of epilepsy in a close relative. Genetic factors are there before a strong feature in the cause of seizures.
Lesions and seizures
Lesions (caused by either disease or injury) which involve the cerebral cortex are also likely to cause seizures. Partial seizures have the highest incidence of a detectable cortical lesion. This is particularly the case when the lesion is in the temporal lobe. Lesions can be caused by disease, brain damage at any age, meningitis, encephalitis and brain abscess, cerebrovascular disorders (such as stroke), cerebral tumors and degenerative diseases of the brain. However, it is also true that around three-quarters of patients with epilepsy have no evidence of an underlying lesion.
What can precipitate seizures?
A number of precipitating factors may provoke a fit in susceptible people or exacerbate established epilepsy. For example, causes can include sleep deprivation, hyperventilation, hypoglycemia and antidepressant drugs. Other factors which are also proven to provoke fits include alcohol and drug ingestion or withdrawal, high fever, anoxia, physical and mental exhaustion, a flickering light, visual patterns, and even procurement to television screens. Uncommon triggers for a seizure include loud noise, hot baths, music or reading.
Sometimes there can be a single seizure associated with some of these factors, such as a spike in temperature, alcohol use or drug withdrawal. These people would not be given a diagnosis of epilepsy my a medical professional, since epilepsy is by definition a chronic brain disorder characterized by recurrent seizures which occurs intermittently over an extended period of time.
Both children and adults with epilepsy have a higher than expected rate of psychiatric disorder. In children this increase can not simply be attributed as a reaction to the stress of coping with a chronic illness. It has been found that children with epilepsy were five times more likely to have psychiatric disorder than children with chronic handicaps not affecting the brain.