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Ohtahara syndrome

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Synonyms and keywords: Early Infantile Epileptic Encephalopathy with Burst-Suppression (EIEE)

Overview

Overview

Ohtahara Syndrome (OS) is the earliest-developing age-related epileptic encephalopathy. It is an extremely debilitating progressive neurological disorder, involving intractable seizures and severe mental retardation. No single cause has been identified, although in many cases structural brain damage is present.[1] The syndrome is outwardly characterized by tonic spasms and partial seizures, and receives its more elaborate name from the pattern of burst activity in an EEG.

Pathophysiology

Pathophysiology

Pathology

There is severe atrophy of both hemispheres of the brain.

Causes

Causes

No single cause of OS has been identified. Less often, the root of the disorder is an underlying metabolic syndrome. No genetic connection has been established.[2]

Epidemiology and Demographics

Epidemiology and Demographics

Age

Seizure onset within the first three months (and often first 10 days) of life.

Natural History, Complications and Prognosis

Natural History, Complications and Prognosis

Complications

  • Mental retardation
  • Infections

Prognosis

Infants with Ohtahara syndrome make very little developmental progress. They remain totally dependent on others and often feed poorly. They often die within the first two years of life because of repeated chest infections. Those who do survive will be severely disabled.

Diagnosis

Diagnosis

Symptoms

  • Excessive sleepiness
  • Seizures – generalised tonic clonic type
  • Age-related epileptic encephalophy, with seizure onset occurring within the first three months (and often first 10 days) of life. Many, but not all, cases of OS evolve into other seizure disorders, namely West Syndrome and Lennox-Gastaut Syndrome.[1]

Physical Examination

Appearance of the Patient

Infant is very floppy and excessively sleepy.

Neurologic

Laboratory Findings

EEG

  • OS is characterized by a “burst suppression” pattern
  • High voltage spike wave discharge followed by little brain wave activity.[1]
Treatment

Treatment

Treatment outlook is poor. Anti-epileptic drugs and steroids may be used to try to control the seizures, but their effectiveness is limited. Most therapies are related to symptoms and day-to-day living. Few infants with focal lesions can have surgery to correct underlying abnormality.

References

References

  1. 1.0 1.1 1.2 National Institute of Neurological Disorders and Stroke (February 14), NINDS Ohtahara Syndrome Information Page Check date values in: |date=, |year= / |date= mismatch (help)
  2. Nabbout, Rima, Early infantile epileptic encephalopathy (PDF) Text ” 2004 ” ignored (help); Text ” July ” ignored (help)
  3. Epilepsy.com Professionals, Tonic, retrieved 2007-11-26 Text ” 2007 ” ignored (help)


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