Absence seizure

(Redirected from Absence epilepsy)
Jump to navigation Jump to search

WikiDoc Resources for Absence seizure

Articles

Most recent articles on Absence seizure

Most cited articles on Absence seizure

Review articles on Absence seizure

Articles on Absence seizure in N Eng J Med, Lancet, BMJ

Media

Powerpoint slides on Absence seizure

Images of Absence seizure

Photos of Absence seizure

Podcasts & MP3s on Absence seizure

Videos on Absence seizure

Evidence Based Medicine

Cochrane Collaboration on Absence seizure

Bandolier on Absence seizure

TRIP on Absence seizure

Clinical Trials

Ongoing Trials on Absence seizure at Clinical Trials.gov

Trial results on Absence seizure

Clinical Trials on Absence seizure at Google

Guidelines / Policies / Govt

US National Guidelines Clearinghouse on Absence seizure

NICE Guidance on Absence seizure

NHS PRODIGY Guidance

FDA on Absence seizure

CDC on Absence seizure

Books

Books on Absence seizure

News

Absence seizure in the news

Be alerted to news on Absence seizure

News trends on Absence seizure

Commentary

Blogs on Absence seizure

Definitions

Definitions of Absence seizure

Patient Resources / Community

Patient resources on Absence seizure

Discussion groups on Absence seizure

Patient Handouts on Absence seizure

Directions to Hospitals Treating Absence seizure

Risk calculators and risk factors for Absence seizure

Healthcare Provider Resources

Symptoms of Absence seizure

Causes & Risk Factors for Absence seizure

Diagnostic studies for Absence seizure

Treatment of Absence seizure

Continuing Medical Education (CME)

CME Programs on Absence seizure

International

Absence seizure en Espanol

Absence seizure en Francais

Business

Absence seizure in the Marketplace

Patents on Absence seizure

Experimental / Informatics

List of terms related to Absence seizure

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Maham Khan [2] Kiran Singh, M.D. [3]

Overview

Absence seizures are one of several kinds of seizures. These seizures are sometimes referred to as petit mal seizures, which is an older term. In absence seizures, the person may appear to be staring into space with or without jerking or twitching movements of the eye muscles. These periods last for seconds, or even tens of seconds. Those experiencing absence seizures sometimes move from one location to another without any purpose.

Classification

Absence seizures may occur in several forms of epilepsy. Absence epilepsy refers to epilepsy in which the only seizures are absence seizures. Absence epilepsy is often characterized by age of onset, e.g., childhood absence epilepsy for epilepsy beginning in childhood between the ages of 3 and 12.

Epilepsy is the most common cause of recurrent seizures, but most seizures are single events that do not recur. Single seizures can be caused by blows to the head, fever (febrile seizure), reactions to medications, tumors, or as a symptom of a larger disease, among other causes.

Just as there are many different kinds of seizures, there are many different kinds of epilepsy. Doctors have identified hundreds of different epilepsy syndromes - disorders characterized by a specific set of symptoms that include epilepsy. Some of these syndromes appear to be hereditary. For other syndromes, the cause is unknown. Epilepsy syndromes are frequently described by their symptoms or by where in the brain they originate. People should discuss the implications of their type of epilepsy with their doctors to understand the full range of symptoms, the possible treatments, and the prognosis.

Presentation

People with absence epilepsy have repeated absence seizures that cause momentary lapses of consciousness. These seizures almost always begin in childhood or adolescence, and they tend to run in families, suggesting that they may be genetic. Some people with absence seizures have purposeless movements during their seizures, such as a jerking arm or rapidly blinking eyes. Others have no noticeable symptoms except for brief times when they are "out of it." Immediately after a seizure, the person can resume whatever he or she was doing. These seizures can happen a few times a day or in some cases hundreds of times a day to the point that the person cannot concentrate in school or other situations. Childhood absence epilepsy usually stops when the child reaches puberty. Absence seizures usually have no lasting effect on intelligence or other brain functions.

It is well known that bright lights, loud noises, and other strong sensory stimuli may trigger seizure episodes.[4]

A person having an absence seizure shows no emotional expressions during the absent period. This indicates that a certain level of consciousness and arousal are needed to experience emotions.

Causes

Life Threatening Causes

Life-threatening causes include conditions which may result in death or permanent disability within 24 hours if left untreated.

Common Causes

Causes by Organ System

Cardiovascular Stroke
Chemical/Poisoning Famine, fetal alcohol spectrum disorder, fetal alcohol syndrome, lindane
Dental No underlying causes
Dermatologic Systemic lupus erythematosus
Drug Side Effect Acetazolamide, beclamide, DPT vaccine, etomidate, heroin, metformin, modafinil, olanzapine, trazodone
Ear Nose Throat No underlying causes
Endocrine Diabetes mellitus, hypoglycemia, ketotic hypoglycemia, oxytocin, polydipsia, prolactin, psychogenic polydipsia
Environmental No underlying causes
Gastroenterologic No underlying causes
Genetic Angelman syndrome, Joubert syndrome, Lennox-Gastaut syndrome, Mowat-Wilson syndrome, spinocerebellar ataxia
Hematologic Porphyria
Iatrogenic No underlying causes
Infectious Disease AIDS, meningitis
Musculoskeletal/Orthopedic No underlying causes
Neurologic Encephalopathy, hydrocephalus, meningitis, porencephaly, postictal state, Rasmussen's encephalitis, shaken baby syndrome, spinocerebellar ataxia, stroke, traumatic brain injury
Nutritional/Metabolic No underlying causes
Obstetric/Gynecologic Menopause
Oncologic No underlying causes
Ophthalmologic No underlying causes
Overdose/Toxicity No underlying causes
Psychiatric No underlying causes
Pulmonary Asphyxia
Renal/Electrolyte Dehydration, systemic lupus erythematosus
Rheumatology/Immunology/Allergy Systemic lupus erythematosus
Sexual No underlying causes
Trauma Traumatic brain injury
Urologic No underlying causes
Miscellaneous No underlying causes

Causes in Alphabetical Order

Complete Differential Diagnosis of causes of Absence seizure

Treatment

The primary goal of treatment of recurrent absence seizures is to prevent accidental injuries that may occur during seizures. For those with frequent seizures the goal of treatment includes preventing the seizures from interfering with learning at school and other activities of daily life.

The goal of treatment with medications for absence seizures is to accomplish the goals above, by eliminating or reducing the frequency of the absence seizures, without causing side-effects more serious than the epilepsy itself.

Certain anticonvulsant drugs are used to minimize the number of seizures episodes. Absence seizures appear to respond well to valproic acid (trade name: Depakote), ethosuximide (trade name: Zarontin), and lamotrigine (Lamictal). Each of these medications has potential side effects, some of them serious. While the most serious side effects are uncommon, a better understanding of the risks and benefits of each of these medications would benefit many parents and guardians in consenting to treatment for their children.

For absence seizures, there is insufficient evidence to know which, if any, of the available medications is best, i.e., having the best combination of safety and efficacy. [5] Nor is it known how long medication must be continued before a trial off medication should be conducted to determine if the individual has outgrown the absence seizures, as children so often do.

To date, there have been no published results of any large, double-blind, placebo-controlled studies comparing the efficacy and safety of these or any other medications for absence seizures.

The U.S. government is currently sponsoring such a study. [6] The purpose of this study is to determine the best initial treatment for childhood absence epilepsy from among valproic acid, ethosuximide and lamotrigine. In addition, the researchers hope to develop methods that may be used in the future to help choose the best medicine for each child diagnosed with absence seizures. The 5-year study began in 2004, and is expected to involve more than 400 children.

Also included in the study will be pharmacokinetics and pharmacogenetics research. Pharmacokinetics is the study of how the body absorbs, distributes, metabolizes, and excretes drugs. Pharmacogenetics is the study of genetic determinants of the response to drugs. Knowledge gained from this study may lead to individualized treatment for children with absence seizures.

Related Chapters

External Links

Template:Diseases of the nervous system Template:Seizures and epilepsy

Template:WH Template:WS sv:Absens