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Showing posts with label PANDAS. Show all posts
Showing posts with label PANDAS. Show all posts

Saturday 13 November 2021

From PANS to PANDAS? Another Problem Solved

 

Source: EpiphanyASD

 

There is a lot written about PANS (Pediatric Acute-onset Neuropsychiatric Syndrome) and PANDAS (Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections) which is a subset of PANS; however they are still not fully recognized as medical conditions.

I prefer to see PANS/PANDAS in the broader context of autoimmune encephalitis, a collection of related conditions in which the body's immune system mistakenly attacks the brain, causing inflammation. The immune system produces antibodies that mistakenly attack heathy receptors in the brain.  Depending on which types of receptors are targeted, you will get different symptoms, plus you will get symptoms from the inflammation.

If they are NMDA receptors, you may have hallucinations and appear to have developed schizophrenia overnight.

It has been suggested that the definition of PANS is too narrow and a broader term called CANS was proposed.  CANS is not exactly the same as PANS.  PANS is the popular term in the US.

“A 2011 paper by Singer proposed a new, "broader concept o childhood acute neuropsychiatric symptoms (CANS)", removing some of the PANDAS criteria in favor or requiring only acute-onset. Singer said there were "numerous causes for CANS", which was proposed because of the "inconclusive and conflicting scientific support" for PANDAS, including "strong evidence suggesting the absence of an important role for GABHS, a failure to apply published [PANDAS] criteria, and a lack of scientific support for proposed therapies".

Moving from PANDAS to CANS (pay-walled)

I do not see why the focus is always on children, because we know that adults can also be affected.

In children and adults with autism it seems that quite often they may suddenly develop verbal or motor tics, as the obvious symptom of autoimmune encephalitis.  These tics gradually disappear when treated with a short course of oral steroids.

One point emphasized by the likes of Susan Swedo, at the US National Institute of Mental Health, is that PANS/PANDAS is not autism.

Non-autistic children can develop PANS/PANDAS, but so can autistic people.

A non-autistic child with untreated PANS/PANDAS would appear to most people as autistic, so similar are the symptoms.

An adult with NMDA receptors encephalitis will very likely be diagnosed as schizophrenic.

The autistic person who develops PANS/PANDAS appears like an autistic person who has encountered a regression. Many of the symptoms of PANS/PANDAS are common symptoms of autism, so the onset of PANS/PANDAS may just look like the already present symptoms have gotten worse.

Susan Swedo has commented that there is nothing to suggest PANS/PANDAS is more common in children with autism. She states that PANS/PANDAS is a condition of onset in early childhood, which is likely to reoccur when re-exposed to the same trigger, but reoccurrence is much less of a risk after 21 years old.

I think most cases of PANS/PANDAS in people with severe autism are never diagnosed and so never treated.  It is just put down as an autistic regression.  How many of those adults with severe autism and extremely challenging behaviors fall into this category?  Given the enormous cost, up to half a million dollars a year, to house this type of person in a care facility with 24-hour support, you would think a little bit more effort should be given to early diagnosis and treatment.

 

A Sceptical World

One of our neurologist readers commented in this blog about how she successfully treated her child’s PANS episode, even though in her country PANS does not exist as a diagnosis and her colleagues at work had no idea how to treat it. Quick intervention required only minor treatment.

In some countries with free universal healthcare, you only get to diagnose and treat PANS if you go outside that system and pay extra.

In the US there are some pretty expensive tests proposed for PANS and CANS.

In mainstream medicine PANS/PANDAS are not generally accepted as conditions and yet Stanford University has had a PANS/PANDAS clinic for a decade.

https://med.stanford.edu/pans/about.html

 

Time for detective work

 



The usual issue I have to manage in spring/summer is what I call summertime raging and dumber in the summer.  Note that a cognitive regression is a very common symptom of PANS/PANDAS.

My solution to summertime raging and dumber in the summer revolves around allergy, mast cells and reducing pro-inflammatory cytokines.

This year some new symptoms developed after summer:

·        Sensory amplification, in the form of sound sensitivity

·        Clinginess to Mum/Mom and separation anxiety

·        Hair twirling, using fingers to twist hair

·        Nail picking, the medical term is Onychotillomania

·        General anxiety

·        Increased urinary frequency, not due to a UTI (urinary tract infection)

·        Aggression and reactive rage (as opposed to predatory rage)

·        Mood disorder, crying for no apparent reason at school and home 

All the above symptoms can be passed off as autism.

Sound sensitivity is a common problem in autism, but Monty was getting so sensitive to sounds that he could not tolerate sitting next to someone eating at home. At school, where it is very noisy, this was not a problem.

Clinginess to Mum/Mom rather merged with the aggression and reactive rage symptoms.  Aggression is a very common problem in severe autism and it is usually directed mainly at Mum.  This time it was not just behaviors, but talking in advance about potential aggressive behaviors, this was new and got worse and worse.

Hair twirling has occurred before and is a common expression of anxiety, which then just becomes a habit, like a stim or tic.  This was previously resolved by a haircut.  This time the short hair did not solve the issue.

Nail picking (Onychotillomania) is when use your index finger to pick at the cuticle on your thumb and end up tearing the skin. This is rather like compulsive hair pulling (Trichotillomania) which is a common feature of OCD (obsessive compulsive disorder).  NAC is used to treat Trichotillomania. 

Anxiety is nearly always an issue in all levels of autism. 

The urinary symptoms of PANS/PANDAS are something that I had not paid attention to earlier. 

We covered polydipsia, drinking too much water, in a special post. This is a big problem for some readers of this blog. 

Thirst – Too much or too little (Polydipsia and Hypodipsia) Vasopressin and Angiotensin

People taking Bumetanide for autism will drink a lot, but should do so only in the few hours after taking the therapy, not all day long.

Autistic people with polydipsia are at risk of death due to low sodium levels (hyponatremia).

Monty was drinking so much I was giving him additional sodium and potassium.

Children with autism often use toilet breaks as an escape from whatever task they have been given.  Monty’s assistant had commented on how he seemed to be trying to escape from her.

The mood disorder was very marked and on one occasion Monty cried at school; his classmates were worried about him and did their best to comfort him.  This had never happened before and there was no apparent trigger. The same thing happened at home a few times, normally in the evening.

After a gradual worsening of the above symptoms, Monty had a viral infection, and he informed us that he had a sore throat. Behaviors then got significantly worse and he had a week off school, more for the behaviours than for the mild flu-like symptoms.  Having then announced that his ear was hurting, we took him to the Ear Nose and Throat doctor. To get to see the doctor you first have to go and get a negative Covid test. The diagnosis was a mild ear infection that might not need an antibiotic, but if it got worse take the antibiotic (Cefpodoxime). This is a β-lactam antibiotic. 

We did cover the non-antibiotic properties of this class of antibiotic in a dedicated post, since many antibiotics have profound anti-inflammatory and other effects not related to killing bacteria.  You can never know with 100% certainty which effect is giving you the benefit.

 

Autism and Non-Antibiotic Properties of Common Beta-lactam Antibiotics

 

 



For anyone interested in trivia. The aerobic mold which forms the basis of this antibiotic, cephalosporin C, was found in the sea near a sewage outfall by Cagliari harbour in Sardinia, by the Italian pharmacologist Giuseppe Brotzu in July 1945. 

If you like sandy beaches like Monty, Sardinia is a great place to visit. Cagliari is in the south, the famous part of Sardinia is Costa Smeralda, on the northern coast, where the celebs go to be seen.

Since Monty’s problem was more behavioral than due to pain in his ear, we started the antibiotic without delay.

Over 5 days, the behaviors began to improve and on day 6 the hair twirling vanished entirely for a day, so clearly something new was going on in his brain.

The mood disorder switched to occasional extreme laughter/happiness, rather than the previous tears.

The behavioral regression started well before the viral infection and ear infection, so it is not just a simple case of a sore throat and a strep infection.

Are all the above symptoms due to PANS/PANDAS?

There actually is a 100% overlap between Monty’s recent symptoms and a list of possible PANS/PANDAS symptoms. Every symptom I listed is on the doctor’s checklist below: -

 

Description of PANS Symptoms

 

Description of PANS Symptoms

1) OCD

Traditional OCD presents with mild obsessions and compulsions that become more involved and burdensome over time. In traditional OCD, symptoms tend to be persistent with minor variance in symptoms (often referred to as a waxing and waning). In contrast, PANS OCD presents with a sudden onset typically from mild or no symptoms to debilitating in an abrupt amount of time. Often, parents recall the exact date of symptom onset, and frequently report “it just came on out of the blue.”

 

Many compulsions are either mental rituals (and therefore difficult to observe) or appear as extremes of an acceptable behavior (e.g., compulsive handwashing). Common OCD rituals in children include: washing/grooming, checking (locks, door), counting, ordering/symmetry, hoarding, restrictive eating, and repetitive questioning.

 

Emerging research suggests different treatment options are available for children with PANS OCD than for children with non-PANS OCD. Understanding the difference between the two forms of OCD allows appropriate interventions to be implemented.

 

2) Eating Restriction

PANS children describe various reasons for not eating normally or adequately, such as: fear of vomiting, sensitivity to taste, smell, and texture, fear food is spoiled, or fear of being poisoned. In some cases, the restricted eating is directly related to body image distortions, including concerns about being overweight (even when the child is normal weight and was previously satisfied with their body habitus.)

 

3) Anxiety

Anxiety frequently presents as constant, generalized anxiety or age-inappropriate separation anxiety.

 

4) Sensory Amplification

PANS children may become uncharacteristically and intensely bothered by smells, tastes, sounds, and textures, causing difficulties with daily routines, such as brushing teeth, riding in a car, eating, and dressing.

 

5) Motor Abnormalities

PANS children may exhibit motor and vocal tics, handwriting changes and/or clumsiness.

 

6) Behavioral Regression

PANS children may display regressed behaviors, such as: baby talk, refusal to carry out age-appropriate grooming activities, tantrums, clinginess, and/or separation anxiety.

 

7) Deterioration in School Performance

Psychological testing of children with PANDAS, a subset of PANS where strep is the infectious trigger, has found impairments on a visual-spatial recall test, on measures of executive function, and on a dexterity test. PANS children may also experience a decreased processing speed, memory issues, and/or difficulty in math and calculation.

 

8) Mood Disorder

Depression, mania, irritability, hypersexuality, emotional lability, and rage have been noted during a PANS exacerbation. Moods may change from happy to sad to angry in moments. Reactive rage (as oppose to predatory rage) may start instantaneously and stop as quickly, leaving the child remorseful and confused.

 

9) Urinary Symptoms

An initial complaint may be urinary frequency. A careful history will often expose additional symptoms. PANS children may develop polyuria (up to many times per hour), frequent urges to urinate, and/or day and night secondary enuresis. These urinary symptoms are not due to UTI, anxiety or OCD type worries.

 

10) Sleep Disturbances

Polysomnography has demonstrated a variety of sleep abnormalities in children with PANS, including initial and middle insomnia, REM behavior disorder, parasomnias, and/or sleep phase shifting. 

 

Since I did introduce the term CANS, here is a comparison of PANDAS, PANS and CANS from a recent Italian paper:- 


CANS: Childhood acute neuropsychiatric syndromes

 

Table 1 - Criteria for PANDAS, PANS, and CANS 

 

PANDAS

1. Presence of OCD and/or a tic disorder

2. Pediatric onset (Symptoms of the disorder first become evident between 3 years of age and the puberty.)

3. Episodic course of symptom severity Abrupt onset of symptoms or dramatic symptom exacerbations. Often, the onset of a specific symptom exacerbation can be assigned to a particular day or week, at which time the symptoms seemed to ‘‘explode’’ in severity. Symptoms usually decrease significantly between episodes and occasionally resolve completely between exacerbations.

4. Association with Streptococcal infection Symptom exacerbations must be temporally related to Streptococcal infection

5. Association with neurological abnormalities During symptom exacerbations, patients will have abnormal results on neurological examination. Motor hyperactivity and adventitious movements

 

PANS

1. Abrupt, dramatic onset of OCD or severely restricted food intake

2. Concurrent presence of additional neuropsychiatric symptoms, with similarly severe and acute onset, from at least two of the following seven categories

1) Anxiety

2) Emotional lability and/or depression

3) Irritability, aggression and/or severely oppositional behaviors

4) Behavioral (developmental) regression

5) Deterioration in school performance

6) Sensory or motor abnormalities

7) Somatic signs and symptoms, including sleep disturbances, enuresis or urinary frequency.

3. Symptoms are not better explained by a known neurologic or medical disorder (Such as Sydenham's chorea, systemic lupus erythematosus, Tourette disorder, or others).

  

Idiopathic CANS

Acute onset before age 18 of behavioral and motor signs encompassing

1. Primary criterion OCD

2. Secondary criteria

1) Anxiety

2) Psychosis

3) Developmental regression

4) Sensitivity to sensory stimuli

5) Emotional lability

6) Tics

7) Dysgraphia

8) Clumsiness

9) Hyperactivity

3. Mono- or polyphasic cours




Treatment

Susan Swedo advises to treat PANDAS with 3 weeks of antibiotics.

Monty’s 2 previous cases of sudden onset motor/verbal tics were resolved by 5 days of Prednisone.  This is a common therapy for a PANS flare-up.  There is a study from Stanford on its benefit.  The sooner you use this therapy, the greater the benefit.

The most important thing with all forms of autoimmune encephalitis seems to be speedy treatment so the condition does not become chronic.  Then you have to use much more invasive and expensive therapies like IVIG and Plasmapheresis.

It is clear that PANS/PANDAS is likely to reoccur.

In Monty’s case the first two instances were very similar.  They were both acute onset tics. The third instance was very different.

Given that Monty’s antibiotic very obviously had a behavioral benefit, we will follow Swedo’s advice and continue for 3 weeks, which is 2 weeks longer than the standard ear infection therapy.

The short course of Prednisone will hopefully complete the therapy and life will go back to normal.

I recall that our neurologist reader, with those sceptical colleagues, did not even need steroids to resolve her child’s problems, NSAIDs were sufficient.  The sooner you treat the symptoms, the less potent the therapy needs to be and the more effective it seems to be.  Some people commence treatment years after the symptoms emerge.

 

Conclusion

One conclusion to this post might have been along the lines of “My god, whatever next?” as if autism brings never-ending problems.

I rather see it as, why did it take me so long to recognize the symptoms?

The answer to that one is that PANS/PANDAS/CANS, or indeed the broader Autoimmune encephalitis, is a family of conditions.  Just because you saw one set of broad symptoms earlier, does not mean you will not face a different subset of symptoms next time.

The urinary symptoms of PANS were a surprise and worth highlighting.

Autistic regressions should be investigated and treated.

On the one hand, doctors, particularly in the US, do like expensive diagnostic tests.  They want certainly and often struggle to treat ill-defined conditions that they have not been taught about.  They prefer not to tinker around, in fact tinkering is frowned upon.

On the other hand, when very expensive testing is done and it identifies in someone a combination of rare genetic dysfunctions associated with autism, nobody thinks to look up each gene and see how to compensate for the usual loss of function - that does not seem to count as medicine.  The genetic diagnosis is crystal clear, but the therapy would definitely require some tinkering around, to perfect it.  But, such tinkering is so frowned upon that the “specialist” just stands well clear and moves on to the next patient.   

Tinkering around is an essential part of fixing practical problems.

In my case of autism, I have not paid $925 for the Cunningham Panel of PANS/PANDAS tests, or even a strep test, or a urine culture test.

The cost of treating the 2 apparent PANS episodes in previous years was about $5 dollars each time.  The cost of the current episode was more, about $15, plus the cost of a visit to the ENT doctor and the required Covid test.  Our neurologist reader likely spent even less for her NSAIDs.

PANDAS, PANS, CANS or just autoimmune encephalopathy, it does not really matter what you call it, prompt intervention will likely resolve the symptoms.





 

Thursday 17 August 2017

Viruses, Bacteria, Fungi, Parasites and Altered Gene Expression, Relevant to Autism






Today’s post started life as a review of how some viruses affect gene expression and may help cause, or just trigger flare-ups in, some neurological disorders ranging from autism to MS (multiple sclerosis). 
Some people with autism are treated with anti-viral drugs and, anecdotally, some do respond well.  This is not yet an area with hard facts and definitive clinical trials.  
It is actually better to first take a few steps back and consider how all microorganisms can play a role in human health by modifying the gene expression of the host (which is you).  There are four broad categories of microorganism.
Each type of microorganism can be countered by a matching category of pharmaceutical.

·        Antibacterials/antibiotics for bacteria

·        Antifungals to kill or prevent further growth of fungi

·        Antivirals to minimize (but often not eradicate) viruses

·        Antiparasitics to kill parasites  (protists)

All of the above categories of microorganism can affect the expression of multiple genes. By either up or down-regulating important genes at critical times during development, long lasting effects can be created, or there may be just transient effects.
Changes in gene expression likely play a role in many neurological conditions and in particular in what I call “flare-ups”, for example in autism, PANS, PANDAS and indeed schizophrenia.
Not all changes in gene expression are bad. The TSO parasites that do seem to help some people’s autism, by down regulating their immune response, very likely are modifying the host’s gene expression, which then reduces their immune response. This is the mechanism developed by the parasite to protect itself from the host (you) and ensure it is not eradicated.
Steroids affect the expression of multiple genes. When a bacteria of virus triggers PANDAS/PANS the positive effect of steroid therapy may well be by “resetting” the expression of certain important genes.  Here again, even though PANDAS/PANS is now treated clinically in the US, much remains unknown.
For those interested, earlier this summer revised treatment guidelines were published for PANDAS/PANS.

In "
Part I–Psychiatric and Behavioral Interventions," Margo Thienemann, MD, Stanford University and coauthors present consensus guidelines for treating the psychiatric and behavioral symptoms of children with PANS/PANDAS. Symptom improvement is aimed at decreasing suffering, improving functioning, and making it easier for the children to adhere to therapeutic interventions.

In "
Part II–Use of Immunomodulatory Therapies," Jennifer Frankovich, MD, and coauthors provide recommendations to help guide the use of therapies targeting the neuroinflammation and post-infectious autoimmunity that are common in PANS-PANDAS.

In “
Part III–Treatment and Prevention of Infections," Michael Cooperstock, MD, MPH, University of Missouri School of Medicine (Columbia) and coauthors representing the PANS PANDAS Consortium, present a consensus guideline for managing the infection components of these neuropsychiatric conditions.

There is research on what virus/bacteria affects which specific gene, but this area of science is in its infancy.
MS (Multiple Sclerosis) a condition that features faulty remyelination, is likely a much simpler condition than autism and yet nobody knows for sure what causes it. It has been suggested that a virus may be the trigger of at least some types of MS, but researchers are decades away from proving anything. So when it comes to microorganisms and autism, it is mainly a case of speculation and the odd N=1 case study. 

Viral triggers of multiple sclerosis 


The relationship between infections and autoimmune diseases is complex and the mechanisms by which infectious pathogens could trigger MS are likely dynamic, i.e., they might change over time and not be mutually exclusive. Epidemiological observations indicate that viral infections could contribute to MS development not only as triggers of disease exacerbations but also as etiological agents, i.e., long before the disease becomes clinically apparent. The two- to three-folds increased risk of developing MS among individuals with history of IM compared with subjects who acquired EBV without symptoms, the almost universal seropositivity for EBV in adults and children with MS, and the steep and monotonic increase in MS risk with increasing titers of antibodies to EBV in apparently healthy adults could suggest that EBV infection is causally linked to MS development. The mechanisms responsible for this association are far from understood. Moreover, the incidence of IM in Western countries (≥ 5%)  exceeds the prevalence of MS in comparable populations (0.1%) by far (more than 50-fold) suggesting that yet unidentified genetic and/or additional environmental factors determine whether symptomatic EBV infection indeed predisposes to MS.

Although one particular MS-causing agent might still be discovered, current data suggest that multiple infections along with noninfectious environmental factors trigger the development of MS. These factors are likely ubiquitous, i.e., highly prevalent in the general population, and they require a permissive genetic background that predisposes for MS development. Future studies investigating infectious pathogens in a complex and heterogenous disease such as MS will benefit from careful and detailed clinical, pathological, and neuroimaging-based patient characterizations and from reproducibility in different study populations. In addition, novel humanized animal models of autoimmune diseases that are simultaneously permissive for viral pathogens which usually infect only humans  should allow investigation of specific aspects of host–pathogen interactions during autoimmune CNS inflammation in vivo. The integration of these data might eventually allow us to better define the role of viruses in the etiology and pathogenesis of MS and how virus–host interactions could be targeted for MS therapy.  

The ubiquitous human herpesvirus 6 may play a critical role in impeding the brain's ability to repair itself in diseases like multiple sclerosis. These findings may help explain the differences in severity in symptoms that many people with the disease experience
What is still not fully understood is the relationship between the extent of the viral infection in the brain and the severity of diseases like multiple sclerosis and other demyelinating diseases such as leukodystrophies and Vanishing White Matter disease. For example, do the number of infected cells need to reach a certain threshold before OPC function is impeded? Are individuals who have congenital HHV6 more vulnerable to severe forms of these diseases?
"More research is needed to understand by which mechanisms the virus impedes the function of OPCs and what impact this has on the progression of these diseases," said Mayer-Proschel. "But it is clear that HHV6, while not necessarily the cause of demyelinating diseases, is limiting the ability of the brain to repair damage to myelin thereby potentially accelerating the progression of these diseases."  

Mainstream and “Alternative” Research  
Not all published research fits with the current mainstream scientific consensus. The mainstream is clearly moving towards the realization that all kinds of things can affect gene expression. One currently fashionable area is the gut microbiota, as in this article:-

Some researchers develop hypotheses that go much further, like this one regarding autism’s elder brother, schizophrenia.


Many genes have been implicated in schizophrenia as have viral prenatal or adult infections and toxoplasmosis or Lyme disease. Several autoantigens also target key pathology-related proteins. These factors are interrelated. Susceptibility genes encode for proteins homologous to those of the pathogens while the autoantigens are homologous to pathogens' proteins, suggesting that the risk-promoting effects of genes and risk factors are conditional upon each other, and dependent upon protein matching between pathogen and susceptibility gene products. Pathogens' proteins may act as dummy ligands, decoy receptors, or via interactome interference. Many such proteins are immunogenic suggesting that antibody mediated knockdown of multiple schizophrenia gene products could contribute to the disease, explaining the immune activation in the brain and lymphocytes in schizophrenia, and the preponderance of immune-related gene variants in the schizophrenia genome. Schizophrenia may thus be a “pathogenetic” autoimmune disorder, caused by pathogens, genes, and the immune system acting together, and perhaps preventable by pathogen elimination, or curable by the removal of culpable antibodies and antigens.

And this one by the same author:-

Herpes simplex virus 1 (HSV-1) can promote beta-amyloid deposition and tau phosphorylation, demyelination or cognitive deficits relevant to Alzheimer's disease or multiple sclerosis and to many neuropsychiatric disorders with which it has been implicated. A seroprevalence much higher than disease incidence has called into question any primary causal role. However, as also the case with risk-promoting polymorphisms (also present in control populations), any causal effects are likely to be conditional. During its life cycle, the virus binds to many proteins and modifies the expression of multiple genes creating a host/pathogen interactome involving 1347 host genes. This data set is heavily enriched in the susceptibility genes for multiple sclerosis (P = 1.3E-99) > Alzheimer's disease > schizophrenia > Parkinsonism > depression > bipolar disorder > childhood obesity > chronic fatigue > autism > and anorexia (P = 0.047) but not attention deficit hyperactivity disorder, a relationship maintained for genome-wide association study data sets in multiple sclerosis and Alzheimer's disease. Overlapping susceptibility gene/interactome data sets disrupt signalling networks relevant to each disease, suggesting that disease susceptibility genes may filter the attentions of the pathogen towards particular pathways and pathologies. In this way, the same pathogen could contribute to multiple diseases in a gene-dependent manner and condition the risk-promoting effects of the genes whose function it disrupts.

Back to Autism
As we have seen previously in this blog, autism is usually polygenic, meaning very many different genes are affected. This does not mean that anything is necessarily defective in those genes, it just means those genes are either over or under-expressed, this means you end up with either too much, or too little, of whatever that gene makes.
So for a polygenic condition, where in one person hundreds of your 22,000 individual genes are likely over or under-expressed, we really do not want anything to come along and further miss-express critical genes.
Many genes are inter-related and so miss-expression of one can trigger a wave of further effects. This can be either good or bad.
The science is still in its infancy, so it will be many decades before it is translated into medicine, but we can certainly already say what may be happening.
The interactome is a relatively new word to describe the whole set of molecular interactions in a particular cell.
 For example, the well-known bacteria H.pylori that can cause stomach ulcers:- 

Over 1,200 interactions were identified between H. pylori proteins, connecting 46.6% of the proteome.

Just this one common bacterium affects half of the entire set of proteins expressed by a genome (the so called proteome).
So we should not be surprised if some bacteria or viruses have a bad, or indeed good, effect on autism.
This also bring us back to the idea of the holobiont and hologenome, which was introduced in an earlier post. The idea is that what really matters in human health is not just your genome, but the totality of what surrounds you, so that means everything living in you, on you and around you. That includes bugs, bacteria and also those of your pet dog.
All of these factors influence how your genes are expressed. During evolution your body has got used to things and if you make rapid changes, you may indeed upset the balance. So while chlorinating water may have an overall good effect, by killing all those bacteria your body had been expecting, there may be some negative effects. Humans evolved living close to animals, be it dogs or farm animals. We saw earlier that pregnant mothers who live with pets produce children with a lower incidence of asthma.
We also reviewed the hygiene hypothesis, which basically says that a bit of dirt is good for you.
So this post, rather than narrowing things down, really broadens them out.  Everything affects everything.  If you rock the evolutionary boat, don’t be surprised if strange things happen.
Taking Somali refugees to live in Sweden increased their incidence of autism. Is that really a surprise? Recall the Somali autism clusters in Sweden and San Diego.
Apparently, the Amish in the US have a low prevalence of autism. Is that really a surprise?  One reader recently suggested sending autistic people to live with the Amish, as a therapy. The possibly effective therapy would have been to send the parents to live with the Amish for a couple of years before the child was born.
So perhaps we should consider much autism, and indeed conditions like asthma, as collateral damage from modern living?  Life expectancy has risen, infant mortality has been greatly reduced, but the downside is that we now have much more autoimmune disease and that includes autism.

Autism and Microorganisms
Now back to autism and the four categories of microorganism.
Can parasites cause autism? Actually we know they can; for example cerebral malaria can result in it. But how often is this case? Probably very rarely.
Can fungi cause autism? Perhaps, but we know from many examples (including in the comments on this blog) that some fungi can make autism worse.  Is the fungus candida albicans growing in the intestines really an issue in most autism? I seriously doubt it, but oral thrush/candidiasis caused by inhaled steroids does seem to make autism worse and is reversible by removing the fungus. The effect seems more likely to be from the candida than the steroid, since inhaled steroids only mildly enter the bloodstream.
Can bacteria cause autism? Well streptococcus bacteria can cause OCD and cognitive impairment (PANDAS).
Can a virus cause autism? Antonio Persico, one of the more serious autism researchers, has suggested that some autism may be caused by polyomaviruses transmitted at conception from father to mother.
https://spectrumnews.org/news/could-a-virus-cause-autism/

Can the rubella virus cause autism? Some serious people do see a possibility, even in people who have been vaccinated.

These both remain controversial hypotheses; but can viruses cause flare ups in autism, later in life? This is also controversial, but I think quite plausible.  It all depends which genes the virus causes to get miss-expressed.
Enough is known to say that odd changes in autism may potentially be triggered by the appearance of specific types of microorganism, but quite possibly most microorganisms have little, or no, negative effect in most people. So it is not a case of all viruses/bacteria will make autism worse, but it is likely true that some may have the potential to do so.
In trying to figure out possible causes of autism flare-ups, due consideration should be given to microorganisms.  This is another case of personalized medicine, with all its potential pitfalls.
The big risk is potentially becoming obsessed with non-existing bacteria, viruses, fungi or parasites.  


Back to Antivirals and Autism 
Finally we come back to where the original idea for this post came from; is there any basis of the use of antiviral drugs to treat autism?
DAN-type doctors do prescribe the antiviral drugs Valtrex, Famvir or Acyclovir.


Antiviral drugs do not destroy their target virus they just inhibit its development.
Most of the antiviral drugs now available are designed to help deal with HIV, herpes viruses, the hepatitis B and C viruses, and influenza A and B viruses.
You identify a virus by looking for antibodies to that specific virus in the blood. You can test for antibodies that suggest if the infection is new and active, called IgM antibodies and you can test for antibodies that show the infection occurred sometime in the past, called IgG antibodies.
You would need to know which virus to test for, the common ones are:-

HSV 1:  Herpes Simplex Virus 1 causes canker sores in the mouth

HSV 2: Herpes Simplex Virus 2 causes genital herpes.

HHV 6: Human Herpes Virus 6 is commonly known as Roseola virus

EBV: Epstein-Barr Virus, causes the illness known as infectious mononucleosis

Measles

Rubella  


“We’re not saying that HSV-2 is responsible for infecting the [fetal] brain and causing autism,” stresses senior author Ian Lipkin, an infectious disease expert and epidemiologist at Columbia. Indeed, fetal infection with HSV-2 is so serious that it frequently leads to miscarriages or stillbirths. Rather, Lipkin suspects that HSV-2 is just one among many environmental insults that, when they arrive at a vulnerable point in fetal development in women predisposed to damaging reactions, may trigger ASD in the fetus.” 

Conclusion: Rate of contact with HSV1 and HSV2 assessed by the mean of detection of specific antibodies was similar between children with ASD and healthy controls.

Conclusion: Levels and seropositivity rate of antibodies to HHV-6 and HHV-8 do not differ between children with ASD and controls.
CONCLUSION: Titre and seropositivity rate of antibodies to CMV and EBV are similar between children with ASD and healthy controls.


Valtrex 
Valtrex seems to be the antiviral most commonly prescribed in autism.  This is an off-label use, meaning Valtrex is not approved to treat autism.  Valtrex is active against most species in the herpesvirus family. In descending order of activity:

So we might assume the people with autism who respond to Valtrex might have one of the above, or similar, viruses. Unless Valtrex has some other modes of action, unrelated to being an anti-viral, which remains a possibility. 

Mitochondrial Disease and Viral Infections
Since this post is already full of speculation, I will add some more. Some people say that their child’s mitochondrial disease was preceded by a viral infection, so how likely is it that a virus can trigger mitochondrial disease and then autism?  Again, this is not something anyone can prove, one way or the other, but it does look like your mitochondria are particularly vulnerable to viruses.
The virus will exploit the mitochondria to further its own development, perhaps in doing so, in some people with a pre-disposition, this triggers a process to chronic mitochondrial dysfunction.  Read the papers below for more on this subject.


Highlights


Mitochondrial dynamics influences mitochondrial and cellular functions.
Mitochondrial dynamics is affected during viral infections.
Viruses exploit mitochondrial dynamics and mitophagy to benefit infectious process.
Virus-altered mitochondrial dynamics determines the outcome of infection.
Disruption of mitochondrial dynamics promotes viral pathogenesis.

If a virus can trigger mitochondrial disease, as we have seen a vaccination can, is there any possible merit in using antivirals years later?
Is there merit treating regressive autism, which is likely to be mitochondrial disease, immediately with antiviral drugs?
Is there merit treating autism flare-ups, that do not respond to PANDAS/PANS therapies, with antiviral drugs?
Is there merit treating MS (multiple sclerosis) immediately on diagnosis with antiviral drugs? Would MS flare-ups respond to antivirals?

My take
If I was to develop MS tomorrow, given there is currently no cure, I think I might want to try an antiviral, just in case it might actually do some good.
My son with classic autism did have a PANDAS-like regression last year, with sudden onset OCD and strange verbalizations. It all went away after a couple of weeks, having been treated as a PANDAS flare-up, as documented in an old post on this blog. If after a viral infection he developed a sudden onset regression I would certainly reread this post.
Readers of this blog with a clear case of mitochondrial disease might want to check for the commonly implicated viruses, since if one was never suppressed this might be something to consider.
So do antivirals have a place in treating autism?  There is no hard evidence to support their use, but I would not at all be surprised if a minority do genuinely benefit. I think the most likely group might be those who have a sudden regression from near typical. As with PANDAS/PANS, the sooner the treatment commences, the better the likely outcome. 
Could antivirals help control flare-ups that can occur in those already with autism? They could well help; ideally you would confirm the presence of the virus first.   

Conclusion
I recently watched an expert clinician talking about irritable bowel syndrome (IBS); he was very open about his opinion that science likely only understands about 30% of the disorder. When it comes to autism I think science may be only at the 10% mark. As a result you have to be very careful about saying anything definitive.
We know that very many things contribute to the prevalence of autism.  It looks more than likely that viruses, bacteria, fungi and parasites may, on occasion, play a role in some people’s autism.
But, just like we know that in some people vaccination can trigger mitochondrial disease and result in an autism diagnosis, this does not mean it is a common cause of autism. Vaccinations have saved hundreds of millions of lives, but it has long been known that they can have side effects and that is why there is a large industry-funded compensation scheme in the US.
So while parasites can in some circumstances lead to autism, this does not mean feeding bleach to children with autism is a clever idea. Nor does filling them with antibiotics to treat a non-existing bacteria.
You can see why mainstream medicine is not eager to treat autism.
Nonetheless, applying that meagre sounding 10% of understanding can yield results, when applied with caution.