PANDAS is NOT currently classified as encephalitis. However, in the acute case histories you’ve read about on this site, PANDAS can cause an Encephalitic-like Sudden Onset.
Dr. Russell C. Dale, Institute of Child Health, University College London, and colleagues have written up groundbreaking work on the nature a form basal ganglia autoimmune encephalitis caused by a virus, Von Economo’s, and its similarities to PANDAS symptoms.
The first commentary with excellent explanation of the basal ganglia: R.C. Dale (2003) Autoimmunity and the Basal Ganglia: New Insights into an Old Disease.
The second study with colleagues is: R.C. Dale, et al (2004) Encephalitis Lethargica Syndrome: 20 New Cases of Evidence of Basal Ganglia Autoimmunity.
Again, typical Encephalitis is different than PANDAS. It is an inflammation caused by a viral or bacterial infection that is present in the brain and physical deterioration is often rapid and severe and it is easily detected via an MRI. This dangerous elevation of symptoms does not seem to occur in PANDAS.
Why can’t we see Basal Ganglia Inflammation with an MRI? Two well-respected Pediatric Neurologists have told me: “It is difficult to prove inflammation because NERVES do not show up in an MRI. The studies have shown some changes in the Virchow Robin Spaces and a Swedo study did show increase volume of basal ganglia. With the brain, we cannot take tissue out and look at under a microscope for inflammation. We must use our own brains to think logically instead.”
One of the Swedo studies the above doctor is referring to is Swedo, et al (2000) – MRI Assessment of Children with OCD or TICS Associated with Streptococcal Infections.
As parents, when we face doctors who will not help us with treatment, it can be helpful to use the words, “an encephalopathic-like episode” has occurred in your child. Encephalitis can be either caused by: 1) Viral 2) Bacterial or even 3) Autoimmune response to a bacteria or virus (as in the rare illness ADEM, Acute Disseminated Encephalomylitis. In ADEM, the white matter of the brain is injured and inflamed). In PANDAS, the basal ganglia are irritated and sets up a negative autoimmune response to the strep bacteria.
The medical community reaction: In all fairness, doctors are perplexed with our children because they do not develop severe/rapid mental and physical debilitation – they relapse and remit in their symptoms. Some children respond rapidly to 10 days of antibiotics. Most children require a longer course of antibiotics. Why this is – is not yet clear – though doctors have observed this to be true. PANDAS’ sudden attacks then slow, relapsing-remitting course is NOT how inflammatory brain illnesses are currently thought about by the medical community.
The topic of encephalitis is brought up only to explain that there is precedent for strange and varied psychological behaviors stemming from brain inflammation, especially where the basal ganglia are involved and that a bacterial irritation with ensuing autoimmune responses can be the culprit.
In PANDAS, initially, the episode is a negative autoimmune response in the basal ganglia to the strep bacteria. It is in the basal ganglia area only. It is not in the white or gray matter itself. There is no infection in the brain. **
* * NOTE: Very rarely, it has happened that in a few PANDAS, an MRI has picked up white or gray matter inflammation and the children are in those cases in need of and will receive immediate treatment for encephalitis.
Attached is a description of encephalitis syndromes where psychological symptoms are nearly identical to that of PANDAS. This is a publication by Oxford University.
Please read this as precedent-only for psychological symptoms, i.e., in Von Economo’s Enceph – for PANDAS-like behaviors, as described by Dale above.
In this viral form of enceph, the basal ganglia are assaulted and the viral infection is also present in the brain. Details in this PDF download of The Oxford Encephalitis Article