MedlinePlus Medical Encyclopedia: Organic brain syndrome

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Organic brain syndrome

Contents of this page:
Illustrations Alternative names Definition Causes, incidence, and risk factors Symptoms	Signs and tests Treatment Expectations (prognosis) Complications Calling your health care provider

Illustrations

Brain

Alternative names Return to top

OBS; Organic mental disorder; Chronic organic brain syndrome

Definition Return to top

Organic brain syndrome is a general term referring to physical disorders (usually not psychiatric disorders) that cause decreased mental function.

Causes, incidence, and risk factors Return to top

OBS is a common diagnosis in the elderly. It is not an inevitable part of aging, however. OBS is not a separate disease entity, but is a general term used to categorize physical conditions that can cause mental changes.

Disorders associated with OBS include, but are not limited to:

Degenerative disorders:
Cardiovascular disorders:
- Arrhythmias -- may cause some types of OBS
- Cardiac infections (endocarditis, myocarditis, etc.) -- may sometimes cause OBS
- Hypertensive brain injury
- Multi-infarct dementia (multiple strokes)
- Stroke
- TIA
Trauma-induced brain injury:
- Chronic subdural hematoma (blood clot causing pressure on brain)
- Concussion
- Intracerebral hemorrhage
- Subarachnoid hemorrhage
Dementia due to metabolic causes
Respiratory conditions -- may cause or aggravate OBS
- Hypoxia (decreased oxygen in the body)
- Hypercapnia (increased carbon dioxide levels in the body)
Infections
- Any acute or chronic infection
- Septicemia (presence in the bloodstream of toxic by-products caused by infection)
- Meningitis
- Encephalitis
Drug and alcohol related conditions
- Intoxication, drug abuse, or alcohol use
- Long-term effects of alcohol, Wernicke-Korsakoff syndrome
- Alcohol withdrawal state
- Withdrawal from drugs (especially sedative-hypnotics and corticosteroids)
Parkinson's disease

Other conditions that may be related to organic brain syndrome include: depression, neuroses, and psychoses of various types, which may occur simultaneously with the OBS.

Symptoms Return to top

Symptoms vary with the specific disease. In general, organic brain syndromes cause varying degrees of confusion, delirium (severe, short-term loss of brain function), agitation, and dementia (long-term, often progressive, loss of brain function).

Signs and tests Return to top

Testing and physical examination vary depending on the specific disorder.

Treatment Return to top

Treatment varies with the specific disorder. Many of the disorders have nonspecific treatments -- primarily supportive care to assist the person in areas where brain function is lost.

Medications may be needed to reduce aggressive behaviors typical of some of the conditions in this category.

Expectations (prognosis) Return to top

See the specific disorder. Some disorders are acute and treatable, but many are chronic or progressive.

Complications Return to top

Loss of ability to interact or function independently is common.

Calling your health care provider Return to top

Call your provider if:

Organic brain syndrome has been diagnosed and you are uncertain of the actual, specific diagnosis
You have symptoms which suggest this problem
You have been diagnosed with OBS and symptoms become worse

Update Date: 8/10/2004

Updated by: Joseph V. Campellone, M.D., Division of Neurology, Cooper University Hospital, Camden, NJ. Review provided by VeriMed Healthcare Network.

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. Copyright 2002 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.