Autoimmune Brain Disease (ABD)

 

Timothy C. Hain, MD

Last edited: 7/2002. Please read our disclaimer.

Presently not posted

ABD defined How common is it Diagnosis Treatment Education Index

 

Autoimmune Brain disease or "ABD" consists of a syndrome of central nervous system which is caused by antibodies or immune cells which are attacking the brain.

The immune system is complex and there are several ways that it can damage the brain. Traditional "autoimmune diseases" includeas Systemic Lupus Erythematosis (SLE), Sjoegren's syndrome (dry eye syndrome), Wegener's granulomatosis, and rheumatoid arthritis can cause or be associated with ABD.  There are are also organ specific disorders such as Hashimoto's thyroiditis and Celiac disease which occasionally are accompanied by ABD. Antibodies to glutamate receptors have ben reported in cerebellar degenerations (Gahring et al, 1997).

How common is autoimmune brain disease ?

ABD is rare, probably accounting for less than 1% of all cases of central disturbances.

What causes autoimmune brain disease ?

The cause of ABD is generally assumed to be related to either antibodies or immune cells that cause damage to the brain. There are several theories as to how these might arise, analogously to other putatative autoimmune disorders:

Bystander damage: In this theory damage to the nrain causes cytokines to be released which provoke, after a delay, additional immune reactions. This theory might explain the attack/remission cycle of disorders such as Multiple sclerosis.

Cross-reactions: In this theory, antibodies or rogue T-cells cause accidental brain damage because the brain shares common antigens with a potentially harmful substance, virus or bacteria that the body is fighting off.

Intolerance: The brain, like the eye may be only an partially "immune privileged" locus, meaning that the body may not know about all of the brain antigens, and when they are released (perhaps following surgery or an infection), the body may wrongly mount an attack on the "foreign" antigen. In the eye, there is a syndrome called "sympathetic ophthalmia", where following a penetrating injury to one eye, the other eye may go blind. This theory is not presently in favor for the ABD.

Genetic factors: There is increasing evidence that genetically controlled aspects of the immune system may increase or otherwise be associated with increased susceptibility to brain injury.

How is the diagnosis of autoimmune brain disease made?

The diagnosis is based on history, findings on physical examination, blood tests, and the results of other tests.

Blood tests for autoimmune disorders include:

 Blood tests for conditions that resemble autoimmune disorders include:

 How is Autoimmune Brain Disease Treated ?

There are several protocols for treatment. In cases with a classic rapidly progressive impairment, a trial of steroids (Prednisone or Decadron) for 4 weeks may be tried. In persons with response to steroids, in most cases a chemotherapy type of medication such as Cytoxan or Methotrexate will be used over the long term ). It has also recently been reported that plasmapheresis may be beneficial.

Autoimmune brain disease is rare making it difficult to study. One can speculate that there might be effective treatments that simply have not been discovered. For example, there are numerous potential treatments that have not been tried in a formal way. Gamma globulin infusions, given monthly, is useful in numerous autoimmune disorders. This treatment is very expensive, which limits its use. Immune modulating drugs such as are used for treatment of MS (beta-interferon, alpha-inteferon, copaxone) are commonly used. Other medications that have coincidental suppression of immune responses, such as minocycline, might be tried.


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