"Maternal infection during pregnancy may be responsible for some portion of autism..."

The quote heading this post - "Maternal infection during pregnancy may be responsible for some portion of autism..." - comes from the paper published by Benjamin al-Haddad and colleagues [1]. They continue a research theme observing that pregnancy infection may have some quite far-reaching effects on the unborn child and their subsequent risk for various conditions / labels / diagnoses (see here for example).

So: "A total of 1 791 520 Swedish children born between January 1, 1973, and December 31, 2014, were observed for up to 41 years using linked population-based registries." As per use of the term 'population-linked registries', this was another study originating in Scandinavia (this time in Sweden) and their important research registries (see here). The important variables being analysed were the presence of "fetal exposure to any maternal infection while hospitalized during pregnancy" and "diagnosis of autism, depression, bipolar disorder, or psychosis among offspring."

Results: "fetal exposure to any maternal infection increased the risk of an inpatient diagnosis in the child of autism... or depression" but not seemingly for bipolar disorder or psychosis. The magnitude of the risk could be described as 'notable' but perhaps not exceptional. 'Urinary tract infection' (UTI) is mentioned as one infection that seemed to increase the risk of offspring diagnosis; something that has been kinda hinted at in other research literature [2] outside of the classic 'acute psychosis and UTI' research that appears in the peer-reviewed literature (see here).

Mechanisms? Well, it doesn't take a genius to figure out that most infection has a bearing on immune system functions and onward concepts like inflammation. There's quite a long history of immune system 'issues' and inflammatory processes being potentially connected to labels like autism and depression (see here and see here respectively) that provide a template for further investigation. This, bearing in mind, that pregnancy is already a time of 'reprogrammed' immune function so that a mothers body can 'tolerate' the developing fetus. As good as any place to start for further investigations...

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[1] al-Haddad BJS. et al. Long-term Risk of Neuropsychiatric Disease After Exposure to Infection In Utero. JAMA Psychiatry. 2019. March 6.

[2] Hadjkacem I. et al. Prenatal, perinatal and postnatal factors associated with autism spectrum disorder. J Pediatr (Rio J). 2016 Nov - Dec;92(6):595-601.

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"the first nationwide population-based study to investigate the risk of CFS in patients with IBD"

The quote titling this post - "the first nationwide population-based study to investigate the risk of CFS [chronic fatigue syndrome] in patients with IBD [inflammatory bowel disease]" - comes from the research published by Shin-Yi Tsai and colleagues [1].

Inflammatory bowel disease (IBD) covers quite a bit of diagnostic ground, but typically refers to ulcerative colitis (UC) or Crohn's disease (CD). There are many similarities between the conditions, but also some important differences too (see here). Both conditions manifest in the bowel (inflammation) and have pathological effects; both also typically show functional bowel symptoms too.

Utilising that fabulous (but sadly now defunct) research resource that was the National Health Insurance Research Database (NHIRD) in Taiwan, researchers set out to "evaluate the subsequent risk of CFS in patients with IBD" on the basis of "possible common pathophysiology between IBD and CFS" among other things. One of those 'pathophysiological' mechanisms quite prominently featuring in the Tsai article is "a similarity to the impaired intestinal mucosa of IBD." Interesting (see here).

So, from a starting population of a million people (or medical insurance records of a million people), authors whittled the figures down to the thousands in two groups: an IBD group (n=2163) and a non-IBD group (n=8652). All were "newly diagnosed" with IBD apparently; and none had a previous diagnosis of CFS "before the index date." Then: "Both groups were followed from the index date until the diagnosis of CFS, withdrawal from the NHI program, or December 31, 2011" with said CFS diagnosis following the Fukuda/CDC criteria.

Results: before heading into the CFS frequency figures according to group, there was another important observation made, potentially pertinent to a gut-brain connection: "The prevalence of depression, anxiety, [and] sleep disorder... was higher in the IBD group than in the non-IBD group." Indeed, the increased frequency of sleep disorder in the IBD group *might* have some important 'connection' with another diagnosis where sleep and 'gut issues' has been mentioned (see here and see here). And I might as well also mention depression and anxiety in that context too (see here).

Continuing: "After adjustment for age, and comorbidities, the risk of CFS was higher in the IBD group than in the non-IBD group (adjusted HR, 2.25; confidence interval [CI], 1.70–2.99)." There was also a possible sex-linked relationship too: "we identified male sex, advanced age, absence of comorbidities, and CD as the predictors of increased CFS risk." There's a pretty little diagram to accompany the Tsai findings (see here) outlining what *could* be going on with regards to IBD and CFS. Terms like 'bacterial translocation' and 'immunoinflammatory pathways' are used, in line with some other research in this area [2]. There's no mention of any psychobabble 'biopsychosocial' or the like in the Tsai paper which is always a good thing.

What else is there to say? Well authors go on to mention about the possibility of "intrinsic defects in IBD patients that precipitates CFS" which could have some quite profound implications for at least some cases of CFS. They added that future work might want to have a look at what certain immunotherapies indicated for some IBDs * might* mean for CFS and it's potential *treatment* too. We'll have to wait and see.

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[1] Tsai S-Y. et al. Increased risk of chronic fatigue syndrome in patients with inflammatory bowel disease: a population-based retrospective cohort study. Journal of Translational Medicine. 2019; 17:55.

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Gluten, mimicry and schizophrenia

The findings reported by Daniela Čiháková and colleagues [1] provide the rather long blogging fodder today, and some interesting observations on how the immune system 'reacting' to gluten in some cases of schizophrenia might have some pretty far-reaching consequences when it comes to other proteins with a similar chemical structure.

OK, first things first, gluten is a protein. It's made up of long chains of amino acids; the building blocks of proteins. As gluten is digested in the gastrointestinal (GI) tract, various enzymes get to work on the protein to break it down into it's constituent amino acids, forming peptides (short chains of amino acids) along the way. The protein gluten and its components like gliadin has a characteristic shape like every protein has. For reasons that aren't yet completely understood, the immune system of some people can sometimes 'mark' normally fairly harmless proteins like gliadin as something that needs dealing with. It does this via the production of antibodies. Antibodies usually mark pathogens like bacteria or viruses, and by doing so, set off a cascade of biological processes to [try and] ensure that such invaders don't take hold and also to remind the immune system of what to look out for. Marking something like gliadin out (which is neither bacteria nor virus!) probably means that the body is detecting gliadin in places it shouldn't be; something that I'll come back to in a minute.

It's not beyond the realms of possibility that when the immune system marks a specific protein as something to keep an eye on, it can make mistakes. If for example, two proteins 'look' similar to each other in a chemical arrangement sense, despite being different proteins with different functions, the immune system can sometimes become a little confused and start to mark both as being an invader on the basis of one already having 'special interest' status. Several descriptions describe such a process: "cross reactivity or mimicry." This accidental marking can sometimes have important repercussions, where such a process is thought to be a basis for autoimmunity.

Čiháková et al detail findings suggesting that just such a process - mimicry - could well be pertinent to some cases of schizophrenia. As already mentioned, they started with the observation that some people diagnosed with schizophrenia have high levels of specific antibodies to gliadin (see here and see here). This follows quite a lot of history linking gluten and schizophrenia together (see here). They wanted to see if as well as presenting with antibodies to gliadin, a cohort of people diagnosed with schizophrenia might also present with elevated antibodies to something called GRINA - Glutamate Ionotropic Receptor NMDA type Subunit Associated with protein 1. They focused in on GRINA because it has a "similar protein structure to gliadin representing a potential target for cross reactivity or mimicry." GRINA also links into glutamate system functioning, something which has also already been mentioned with schizophrenia in mind (see here).

There's another detail about the Čiháková study which relates to a point I touched upon earlier, on the possible hows-and-whys of gliadin antibodies being found in cases of schizophrenia: enhanced gut permeability a.k.a leaky gut. Researchers also analysed serum samples for the presence of something called Anti-Saccharomyces Cerevisiae antibodies (ASCA) which they say are "related to gut permeability." This follows other research in a similar vein (see here) and the suggestion that something like abnormal gut permeability *could* be implicated in some cases of schizophrenia.

Results: looking at serum samples of 160 people diagnosed with schizophrenia and 80 not-schizophrenia controls, researchers observed "a higher prevalence of positivity to ASCA IgA... and IgG" in those with schizophrenia. This tallies with the leaky gut hypothesis. They also reported that "GRINA IgG was higher in schizophrenia patients than in healthy controls." Putting these results together, they concluded that the mimicry hypothesis might well be pertinent to some schizophrenia.

There is a lot more work required in this area for sure. This will need to involve further investigation of the hows-and-whys of any such mimicry, and whether such a process could be a potential target for intervention. Indeed, in that intervention vein, I'm wondering whether use of a gluten-free diet for some with schizophrenia who have such antibodies (to gluten and other things like GRINA) might be an option. There's also merit in looking further at the issue of gut permeability and schizophrenia; whether again adoption of a gluten-free diet (which can positively affect gut permeability measurements) might be indicated, perhaps alongside other therapeutic targets.

But this area of research is interesting, and adds to the quite long research history linking food components and some behavioural / psychiatric labels...

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[1] Čiháková D. et al. Gut permeability and mimicry of the Glutamate Ionotropic Receptor NMDA type Subunit Associated with protein 1 (GRINA) as potential mechanisms related to a subgroup of people with schizophrenia with elevated antigliadin antibodies (AGA IgG). Schizophr Res. 2019 Jan 23. pii: S0920-9964(19)30007-6.

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"NMDAR-antibody encephalitis might best be described as a mixed mood-psychosis syndrome"

Every once in a while a paper comes along with the potential to 'really shift opinions'. I'm gonna place the publication by Adam Al-Diwani and colleagues [1] in that category, and their (pre-registered) systematic review around the topic of N-methyl-D-aspartate receptor (NMDAR)-antibody encephalitis.

NMDAR-antibody encephalitis reflects a condition characterised by the immune system failing to identify self as self. For whatever reason, the immune system starts treating specific cells of the body as 'enemy' and mounts an immune attack against them. This results in the formation of specific antibodies - "against the NR1 subunit of the NMDA receptor" [2] - also typically resulting in "psychiatric features before progressing to seizures, a complex movement disorder, autonomic dysfunction, and hypoventilation." The book and film 'Brain on Fire' is about as good an education as you might need on the personal costs and effects of NMDAR-antibody encephalitis.

As Al-Diwani et al mention, things are getting rather interesting for NMDAR-antibody encephalitis in psychiatric circles. Awareness of the condition is growing, albeit with further 'flesh on the bones' required in terms of clinical features to look out for which could accompany the biological testing for the condition. Researchers sought to do just that: "the psychopathology of NMDAR-antibody encephalitis needs to be clearly defined to encourage accurate clinical identification and prompt treatment."

They trawled the peer-reviewed scientific literature looking for mention of NMDAR-antibody encephalitis, and eventually settled on over 300 records describing 1100 people in total. Over 460 of those people were identified with "definite NMDAR-antibody encephalitis according to consensus criteria" and their psychiatric features were examined. "The authors extracted 50 lower-level psychiatric features reported in these 464 patients, defined their frequency, and grouped them into eight higher-level features." Further comparisons were made leading to them assessing "whether individual patients were best described by one or by several psychiatric diagnoses" used as comparators.

Various features were potentially important: "The most common higher-level features were behaviour (316 [68%]), psychosis (310 [67%]), mood (219 [47%]), catatonia (137 [30%]), and sleep disturbance (97 [21%]), and these features frequently coexisted in individual patients." Various interesting graphs and figures are presented by the authors to illustrate their findings. The end result was the description of NMDAR-antibody encephalitis as "polymorphic and not to respect traditional psychiatric classifications." That being said, the notion of a "mixed mood-psychosis syndrome" represents as good a description as any based on the Al-Diwani findings.

Other details? "Overall, the age and sex distribution centred around young women, and the frequency of cases was greatly reduced after 40 years of age." Important information there about a potentially vulnerable group. Also: "139 (30%) of 464 cases were associated with ovarian teratoma, seven (2%) with previous herpes simplex virus encephalitis, and 24 (5%) with pregnancy." Ovarian teratoma is described as a rare cancer categorised as a 'germ cell tumour'. The *link* between ovarian teratoma and NMDAR-antibody encephalitis is something that has been of interest for a few years [3] and perhaps provides a clue for further investigation.

I do stand by my 'game-changer' type comment of the Al-Diwani paper. There is of course more to do in this area (including examining a curious link between NMDAR-antibody encephalitis and 'an autistic-like regression' in some children which is becoming all the more prominent in the research literature [4]). Putting all the various features identified by the authors into a useful set of diagnostic criteria is also a next step...

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[1] Al-Diwani A. et al. he psychopathology of NMDAR-antibody encephalitis in adults: a systematic review and phenotypic analysis of individual patient data. The Lancet Psychiatry. 2019. Feb 11.

[2] Finke C. A transdiagnostic pattern of psychiatric symptoms in autoimmune encephalitis. The Lancet Psychiatry. 2019. Feb 11.

[3] Acién P. et al. Ovarian teratoma-associated anti-NMDAR encephalitis: a systematic review of reported cases. Orphanet J Rare Dis. 2014;9:157.

[4] Khundakji Y. et al. Anti-NMDA receptor encephalitis in a toddler: A diagnostic challenge. International Journal of Pediatrics and Adolescent Medicine. 2018; 5: 75-77.

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"parental asthma was associated with slightly elevated risk of ASD in offspring"

The paper by Tong Gong and colleagues [1] provides the blogging fodder today and the finding that "parental asthma was associated with slightly elevated risk of ASD [autism spectrum disorder] in offspring."

As unusual as it might sound to some people that a condition primarily affecting the lungs *might* show a connection to a developmental diagnosis in offspring, this is not the first time that asthma and autism has been talked about on this blog (see here and see here). Granted, much of that previous peer-reviewed research has been looking at the possible *connection* between asthma and autism diagnosed in the same person (albeit not necessarily always describing a link). But there is some research history connecting the two labels. Indeed, one of the primary comorbidities that can follow a diagnosis of autism - attention-deficit hyperactivity disorder (ADHD) - seems to have an even stronger *association* with asthma (see here).

Gong et al set out to investigate a few important issues: "the association between (a) maternal/paternal asthma and offspring ASD, and (b) prenatal exposures to β2-agonists, other asthma medications and offspring ASD." It would be difficult to describe the Gong study as 'underpowered' given that their use of those fabulous Scandinavian population registries - this time in Sweden - covering "all children (N=1,579,263) born in Sweden 1992-2007." From the total population, researchers identified some 22,000 children diagnosed with an ASD. They looked at their exposure to "parental asthma or prenatal asthma medications" and compared the data with other populations (not diagnosed with autism) including various degrees of siblings and extended family members.

As per the title of this post, a possible *association* was revealed between parental medical history of asthma and offspring risk of a diagnosis of ASD. Asthma in either parent seemed to show a connection, but maternal asthma showed the stronger connection. Also: "The risk of offspring ASD in mothers with asthma showed similar estimates when adjusting for shared familial factors among paternal half-siblings... full-cousins... and half-cousins." This suggests that familial factors were not 'confounding' factors. Another detail is important to mention: "Prenatal exposure to asthma medications among subjects whose mothers had asthma was not associated with subsequent ASD." This is an important detail. It mirrors the findings reported in the paper by Su and colleagues [2] looking at another Scandinavian cohort, and their conclusion: "children born to women who used β2AA [β2-adrenoreceptor agonist] during pregnancy have an increased risk of ASDs in later life" with the caveat that risk of offspring autism was "more likely due to underlying maternal diseases rather than the exposure to β2AA itself."

Implications? Well, several. Not least that more study is required looking at the biological and genetic links between autism and asthma. Y'know, something along the lines of the fact that 'autism genes are probably not just genes for autism' (see here) and how autism has been previously studied in the context of lung architecture too (see here).

What else? How about examining the possibility of some shared biological mechanisms also at work? Perhaps start with inflammation for example [3] and work through other potential immune-related issues as well (see here). And how about also thinking about the possibility of shared 'exposure' events being potentially important? Asthma is a condition affecting the lungs. Something like air pollution is therefore a prime suspect when it comes to the development and continuation of the condition. Likewise, air pollution is no stranger to the autism peer-reviewed research landscape (see here for example). Is it possible that air pollution might be implicated in asthma and autism?

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[1] Gong T. et al. Parental asthma and risk of autism spectrum disorder in offspring: a population and family based case-control study. Clin Exp Allergy. 2019 Feb 11.

[2] Su X. et al. Prenatal exposure to β2-adrenoreceptor agonists and the risk of autism spectrum disorders in offspring. Pharmacoepidemiol Drug Saf. 2017 Jul;26(7):812-818.

[3] Murdoch JR. & Lloyd CM. Chronic inflammation and asthma. Mutat Res. 2010;690(1-2):24-39.

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"people on the autism spectrum have a high prevalence of physical and mental health conditions in midlife and old age"

Should anyone really be that surprised by the findings reported by Lauren Bishop-Fitzpatrick & Eric Rubenstein [1] talking about "a high prevalence of physical and mental health conditions in midlife and old age" when it comes to autism?

Well, yes and no. No, because things like 'psychiatric symptoms and disorders' have already been talked about with regards to older age adults with autism [2] (see here also), alongside various other 'medical comorbidity' being noted in this group (see here). But also yes, because the scale of the physical and mental health conditions identified by Bishop-Fitzpatrick & Rubenstein is quite literally jaw-dropping: "immune conditions (70.6%), cardiovascular disease (49.0%) and its risk factors (46.2%), sleep disorders (85.3%), gastrointestinal disorders (49.7%), neurologic conditions (55.9%), and psychiatric disorders (72.0%) were highly prevalent in our full sample." Said full sample consisted of "de-identified Medicaid claims data for 143 adults with a recorded autism spectrum disorder diagnosis aged 40–88 years."

Researchers also mention how 44% of their sample had an intellectual (learning) disability. This kinda accords with various other data on this topic (see here). Other observations mentioned by the authors also complement existing (peer-reviewed scientific) knowledge that: (a) intellectual (learning) disability seems to bring about an increased risk of epilepsy appearing alongside autism (see here), and (b) depression and anxiety prevalence seems to be particularly elevated in those with autism without any accompanying learning disability (see here) (assuming that depression and/or anxiety are actually being screened for in those with autism + learning disability).

What do the collected data imply? Well, screening is important. Screen and screen and screen and screen. Screen for lots of things, and if something turns up, treat / manage it. If your average Jane or Joe turned up at their Doctors office with a sleep disorder or the symptoms of cardiovascular disease, medical professionals would do something about it. If the Doctor also knew that Jane / Joe might, for example, be more likely than usual to be in receipt of certain classes of medicines that potentially elevates such risks further, they'd be even more keen to screen and intervene. So it should be the same if Joe or Jane is diagnosed with autism or an autism spectrum disorder (ASD).

I'd also suggest that such data should really be leading to a lot more questioning about why? Why do people on the autism spectrum seem to be at particularly high risk of 'immune conditions' or 'digestive disorders'? Are there potential genetic links between autism and such conditions as per the notion that 'autism genes aren't necessarily just genes for autism' (see here) or that such genes might also affect other biological systems as well as the grey-pink matter floating around the skull (see here for example)? Are there other intricate connections between such classes of conditions as per the idea that sleep problems seem to follow gut problems for some (see here)? Why? Pain, discomfort, something else? And don't even get me started on the whole 'immune system - autism' connection (see here for example) which has been known about for many, many, many years. Known about but brushed under the carpet by some.

And whilst talking about the research tag-team that is Bishop-Fitzpatrick & Rubenstein, I once again would direct you to another important paper of theirs [3] about how we need to be very careful about using the word 'comorbidity' when referring to the various mental and physical issues that are over-represented around autism. As we've seen from other research (see here and see here), the core features of autism may very well predispose to a lot more than just autism and, in that respect, this might go way beyond just comorbidity...

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[1] Bishop-Fitzpatrick L. & Rubenstein E. The physical and mental health of middle aged and older adults on the autism spectrum and the impact of intellectual disability. Research in Autism Spectrum Disorders. 2019. Jan 29.

[2] Lugo-Marín J. et al. Prevalence of psychiatric disorders in adults with autism spectrum disorder: A systematic review and meta-analysis. Research in Autism Spectrum Disorders. 2019; 59: 22-33.

[3] Rubenstein E. & Bishop-Fitzpatrick L. A matter of time: The necessity of temporal language in research on health conditions that present with autism spectrum disorder. Autism Res. 2019 Jan;12(1):20-25.

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"Zika Virus as a Possible Risk Factor for Autism"?

The paper by Vianna and colleagues [1] provides the blogging fodder today, discussing a potentially important topic around whether "the fetal brain infection caused by ZIKV [Zika virus] could predispose to ASD [autism spectrum disorder]."

Just before anyone gets the impression that a *link* has been found between Zika virus exposure and autism or autism spectrum disorder (ASD), I'm going to say no, not yet. The current peer-reviewed evidence at the time of writing this post has not identified autism as an outcome following exposure to the Zika virus. That's not to say that various other neurodevelopmental issues have not been associated with Zika virus exposure (see here for example) or that Zika virus exposure might not have biological consequences akin to that noted in some autism [2]. But as far as I'm aware, there is no peer-reviewed science yet suggesting that autism is for example, over-represented among those exposed to Zika virus in-utero. Not yet anyway.

Nonetheless, Vianna et al go through a number of lines of evidence suggesting how autism *could* be an outcome of Zika virus exposure. They start by talking about how Zika virus exposure during pregnancy can have a devastating effect on the developing child (see here) as a function of its teratogenic status. Severe microcephaly (small head size), a cardinal feature linked to infants' Zika virus exposure during pregnancy, has notable effects on the brain and its development, and is one of the more noticeable effects associated with Zika virus exposure in-utero. But further: "this phenotype is now considered only “the tip of the iceberg” and there is a spectrum of less severe abnormalities after congenital Zika infection."

Authors go on to talk about how pregnancy is a time of 'change' when it comes to maternal immune system functions, as a reprogrammed immune system has to become 'tolerant' of the developing foetus. Such reprogramming means that the foetus can survive and thrive. It also however means that the maternal immune system might be more susceptible to certain infections, where for example "opportunistic infections... take advantage." This is also the point where autism enters into the conversation, and the idea that exposure to various infections (viral and bacterial) occurring during pregnancy "can alter [offspring] brain development and are associated with alterations, such as brain calcifications, microcephaly, and neurodevelopmental disorders." I've covered a few possible examples on this blog with autism in mind (see here and see here).

Putting all this together, as well as talking about some of the immune system chemistry that *might* link Zika virus exposure and autism, and the authors come up with a model of 'neuroimmunomodulation' talking about "an ineffective anti-viral response" and increased levels of pro-inflammatory cytokines as being potentially important. I'll also provide another quote from Vianna which is similarly intriguing: "Moreover, in the case of ZIKV, previous infections with other flaviviruses, such as dengue virus and yellow fever, may trigger a secondary immune response of differential magnitude given the great molecular similarity of some immunogenic epitopes among these correlated viruses."

Reiterating that there is currently no link between Zika infection and risk of autism, I do find the Vianna paper interesting. It offers some testable hypotheses that could examined in the lab and beyond. It also provides some further support for the various surveillance and monitoring initiatives that remain in place with regards to Zika virus and the promise of further important data to come from them.

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[1] Vianna P. et al. Zika Virus as a Possible Risk Factor for Autism Spectrum Disorder: Neuroimmunological Aspects. Neuroimmunomodulation. 2019 Jan 10:1-8.

[2] Beys-da-Silva WO. et al. Zika Virus Infection of Human Mesenchymal Stem Cells Promotes Differential Expression of Proteins Linked to Several Neurological Diseases. Mol Neurobiol. 2018 Oct 30.

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"maternal obesity and overweight were significantly associated with [offspring] increased ASD risk"

The title heading up this brief post - "maternal obesity and overweight were significantly associated with [offspring] increased ASD [autism spectrum disorder] risk" - comes from the results published by Xian-Yang Lei and colleagues [1].

Under systematic review and meta-analysis conditions, researchers basically found what many people had suspected for quite a while, insofar as maternal weight, before or during pregnancy, being a 'risk factor' for an offspring diagnosis of autism or ASD. They arrived at their conclusion based on "13 eligible studies for meta-analysis (involving 943,293 children and 30,337 cases)" which collectively found that "both maternal obesity... and maternal overweight... were significantly associated with ASD, while maternal underweight was not associated with ASD." Researchers also looked at paternal weight as a possible risk factor for offspring autism but found no statistical association between paternal obesity, overweight or underweight based on the available data (limited to only three studies).

Mindful of the potential for 'stigma' to set in with such investigation, and likewise being careful not to generalise too much from such findings, the Lei results point to both the requirement for more research in this area and a possible 'intervention' route towards reducing the risk of offspring autism: "pre-pregnancy weight control is suggested." I've covered this topic numerous times on this blog (see here and see here and see here for examples) and have concluded that whilst correlation is not the same as causation and that pre- and peri-pregnancy weight is often intricately tied into other features of the condition known as metabolic syndrome, immune function and in particular inflammation, are perhaps important areas for further assessment. Research should perhaps head in that direction, and see what further crops up...

And as if to further prove the point [2]...

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[1] Lei XY. et al. Association between parental body mass index and autism spectrum disorder: a systematic review and meta-analysis. Eur Child Adolesc Psychiatry. 2018 Nov 23.

[2] Windham GC. et al. Maternal Pre-pregnancy Body Mass Index and Gestational Weight Gain in Relation to Autism Spectrum Disorder and other Developmental Disorders in Offspring. Autism Res. 2018 Dec 21.

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"by the time ongoing fatigue was established, the immune activation was no longer present"

The quote heading this post - "by the time ongoing fatigue was established, the immune activation was no longer present" - comes from some media coverage of the paper published by Alice Russell and colleagues [1]. Said paper observed some interesting results in relation to the use of interferon-alpha (IFN-α) "used in the treatment of chronic Hepatitis C Virus (HCV) infection" and what this *could* mean in relation to a "proxy model of chronic fatigue syndrome."

The long-and-short of the Russell results and their possible application to chronic fatigue syndrome (CFS) is that for quite a few years now there have been rumblings that at least some cases of CFS (also known as myalgic encephalomyelitis, ME) might be *associated* with a viral hit-and-run encounter. By saying 'hit-and'run' I mean that an initial viral or bacterial infection is experienced which induces the symptoms of CFS. Said infection then eventually disappears for whatever reason(s) but leaves persisting symptoms such as long-term fatigue and more. Further explanation of this hypothesis can be seen in another of my posts on CFS (see here).

So: "Fifty-five patients undergoing IFN-α treatment for chronic HCV were assessed at baseline, during the 6–12 months of IFN-α treatment, and at six-months post-treatment." The use of IFN-α is clinically indicated for HCV infection as part of an antiviral therapeutic regime ("IFN-α and ribavirin"). Various biological parameters were assessed in the 55 participants as well as in separate groups of those diagnosed with CFS and so-called "healthy volunteers."

Treatment with IFN-α induced fatigue in quite a few of those being treated for HCV infection. Most cases of fatigue resolved at 6-months post-treatment but for some, fatigue remained and for about 30%, levels of fatigue were "higher six-months post-treatment than at baseline." The authors looked at the biological results obtained for those with 'persistent fatigue' (PF) and compared them with those with 'resolved fatigue' (RF) to see if they could discern some differences.

They came up with a few important group observations: "Subjects who later develop PF have higher fatigue in response to IFN-α", "Subjects who later develop PF have higher IL-10 levels before treatment, and IL-6 and IL-10 levels in response to IFN-α", and "Psychosocial and clinical risk factors do not distinguish PF from RF subjects." What this all amounts to is that within quite a small participant group: "findings from this study support the hypothesis that abnormal immune mechanisms are important in CFS, but only early in the course of the illness, around the time of the trigger, rather than when the syndrome is established." Further the study: "confirms the importance of the acute fatigue response to the trigger, rather than of the recovery period preceding the illness."

There is more to do in this area bearing in mind that CFS is a pretty heterogeneous condition both in terms of symptom onset and the course of the illness. Researchers also admit that they "can only speculate at this stage on whether or not the mechanisms underlying the persistence of fatigue in CFS and IFN-α induced PF are related" and their suggestion of a proxy model. Others who have covered this study have said similar things (see here). This is also important given other results reported by the authors on those diagnosed with CFS compared with those 'healthy' controls/volunteers.

Still, there are some interesting observations made by Russell et al and once again, such results hopefully move CFS further away from the biopsychosocial (BPS) model of old that has seemingly done considerable damage to those diagnosed (see here and see here). Indeed, such post-infective thinking kinda brings CFS back full circle...

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[1] Russell A. et al. Persistent fatigue induced by interferon-alpha: a novel, inflammation-based, proxy model of chronic fatigue syndrome. Psychoneuroendocrinology. 2018 Dec 17.

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Pioglitazone for autism?

Enjoyed Christmas? Welcome back. Onward...

"Pioglitazone is well-tolerated and shows a potential signal in measures of social withdrawal, repetitive, and externalizing behaviors."

So said the findings reported by Lucia Capano and colleagues [1] (open-access) describing preliminary efforts to "elucidate the maximum tolerated dose, safety, preliminary evidence of efficacy, and appropriate outcome measures in autistic children ages 5–12 years old" taking the hypoglycemic medicine called pioglitazone. The results obtained from this phase II pilot study - "a 16-week prospective cohort, single blind, single arm, 2-week placebo run-in, dose-finding study of pioglitazone" - suggest that further research on this medicine in the context of autism is warranted.

Capano et al provide quite a lot of information about the whys-and-wherefores of pioglitazone use in the context of autism. They talk about immune system 'issues' and inflammation being no strangers to autism research. They talk about various findings in relation to immune signalling and autism, drawing on data from several investigations that have looked at compounds like the cytokines and chemokines. Pioglitazone fits into this story by way of it being "an agonist of peroxisome proliferator activated receptor (PPAR)-ϒ." Activation of PPAR-ϒ leads to "insulin sensitization and enhances glucose metabolism." It also seemingly has an anti-inflammatory role to play too. Through the use of  pioglitazone ramping up the action of PPAR-ϒ, so researchers opined that this could be useful for some people diagnosed with autism where immune system and behaviour might meet...

Unlike other trials of pioglitazone in the context of autism [2], the Capano study was more exploratory than 'gold-standard' in it's design. It did however include both behavioural and biological components, where various behavioural outcome measures were included alongside the describing of various "research bloodwork" that included various cytokines ("IL1-β, IL-10, and TNF-α in plasma; IL-6 in serum") that have been discussed in other studies with autism in mind (see here for example).

Alongside those initial results mentioned in the opening sentence of this post, there are a few other important points to make. So: "Overall, pioglitazone was well tolerated." Welcome news indeed. Researchers also noted that: "There were no serious adverse events (SAEs) in any of the doses within the range tested (0.25 mg/kg, 0.5 mg/kg, and 0.75 mg/kg)." This is important in the context that all medicines have the propensity for 'adverse effects' for some people, and pioglitazone is no different. Given also the focus on medication and weight gain in the context of autism (see here for example), it's a bit of relief to see that, for the study period at least, authors reported that: "BMI [body mass index] did not change significantly during the study."

I'm not going to go to heavily into the behavioural changes noted over the study period on this occasion, because these are preliminary and one has to be careful with any interpretation. I do however want to mention some of the biological results; namely: "Significant changes with treatment occurred with both IL-6 and IL-10" and "IL-1β and TNF-α did not change significantly with treatment." The authors note that the IL-6 and IL-10 findings - "decreasing IL-6 and increasing IL-10" - were "consistent with the known effect of PPAR-gamma agonists like pioglitazone." This is an interesting finding.

Cumulatively, such results suggest that quite a bit more research focus is needed on pioglitazone in the context of [some] autism. But for now, it looks quite promising (again [3])...

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[1] Capano L. et al. A pilot dose finding study of pioglitazone in autistic children. Molecular Autism. 2018; 9: 59.

[2] Ghaleiha A. et al. A pilot double-blind placebo-controlled trial of pioglitazone as adjunctive treatment to risperidone: Effects on aberrant behavior in children with autism. Psychiatry Res. 2015 Sep 30;229(1-2):181-7.

[3] Boris M. et al. Effect of pioglitazone treatment on behavioral symptoms in autistic children. J Neuroinflammation. 2007;4:3.

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"Anti-Candida albicans IgG antibodies in children with autism spectrum disorders"

The quote titling this post - "Anti-Candida albicans IgG antibodies in children with autism spectrum disorders" - reflects the title of the paper by Paul Ashwood & Heather Hughes [1] who set out to "determine if children with ASD [autism spectrum disorder] exhibit elevations in antibodies that target C. albicans, indicating current or previous overgrowth of this fungal species." Such work is based on the still developing idea that "individuals with ASD have significant aberrations in the composition of their gut microbiota, known as dysbiosis" and part of that dysbiosis might also stretch to fungal as well as bacterial species.

Candida albicans also known as C. albicans is described as a 'opportunistic pathogenic yeast' quite readily observed in quite a large proportion of 'healthy adults'. For most people, this yeast does not cause any issues. On occasion however, C. albicans can lead to problems, particularly among those who are described as 'immunocompromised'. This is not the first time that C. albicans has been examined in the context of autism. Granted, the studies so far have been relatively small scale [2] and in requirement of follow-up [3] but this topic is no stranger to the peer-reviewed science literature. The Ashwood & Hughes paper should also be viewed in the context of other science discussions from this authorship group [4]; indeed several [5].

So: "We measured anti-C. albicans immunoglobulin (IgG) in plasma from eighty children enrolled in the UC Davis MIND Institute CHARGE study." IgG antibodies, represent 'immune status' with regards to a history of encountering specific pathogens. So, being positive to "anti-C. albicans immunoglobulin (IgG)" means that someone has been exposed to C. albicans at some point in their lifetime and retained something of an 'immune memory' to it. This subsequently means that your immune system is 'primed' in case that specific pathogen is encountered once again.

Results: "Plasma anti-C. albicans antibody positivity was found in 36.5% (19/52) of children with ASD. Anti-C. albicans antibodies in typically developing controls was (14.3%; 4/28)." I'm sure that you can see the disparity between the groups, bearing in mind that this was not an 'all-or-nothing' finding in relation to the separation of the groups. I should also mention that researchers also reported that gastrointestinal (GI) symptoms, also examined in this cohort, did not seemingly play a role in C. albicans antibody positivity.

Where next for this area of investigation? Well, alongside perhaps taking these results into consideration with other findings from this research group (see here), the authors mention that "exploring fungal composition within the gut as well as metabolic byproducts of yeast species such as d-arabinitol and ethanol, and identifying associations these might have with behaviors in ASD" could be one direction. In light of other independent research (see here), I'd say that was a sensible next step to take.

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[1] Ashwood P. & Hughes HK. Brief Report: Anti-Candida albicans IgG antibodies in children with autism spectrum disorders. Front. Psychiatry. 2018. Nov 26.

[2] Ekiel A. et al. Intestinal microflora of autistic children. Med Dosw Mikrobiol. 2010;62(3):237-43.

[3] Iovene MR. et al. Intestinal Dysbiosis and Yeast Isolation in Stool of Subjects with Autism Spectrum Disorders. Mycopathologia. 2017 Apr;182(3-4):349-363.

[4] Hughes HK. et al. The Gut Microbiota and Dysbiosis in Autism Spectrum Disorders. Curr Neurol Neurosci Rep. 2018 Sep 24;18(11):81.

[5] Hughes HK. et al. Immune Dysfunction and Autoimmunity as Pathological Mechanisms in Autism Spectrum Disorders. Front. Cell. Neurosci. 2018.

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"a 256-peptide immunosignature with the ability to separate ME/CFS cases from controls"

The findings reported by Oliver Günther and colleagues [1] (open-access available here) really interested me. They interested me because they talked about the "hit and run" hypothesis being pertinent to myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), where "a pathogen or other immunological insult experienced by a subject may be gone, but leaves behind physiological disequilibrium." They interested me because researchers turned to "an immunosignature assay (ISA) that employs a microarray of thousands of random-sequence peptides to interrogate antibodies in a broad and unbiased fashion" to try and pick out the biological effects of the 'hit and run' hypothesis in relation to ME/CFS. And they interested me because researchers reported that they were able to identify "a 256-peptide signature that separates ME/CFS samples from healthy controls, suggesting that the hit-and-run hypothesis of immune dysfunction merits further investigation." Lots of interesting things (honest!).

The Günther paper is open-access so doesn't really need too grand an explanation from me. The long-and-short of it was that following the adoption of a discovery and validation methodology (an increasingly favoured option in ME/CFS research circles), authors came up with a sort of 'biological fingerprint' "optimally separating ME/CFS cases and controls" based on the examination of serum samples. They also noted that in amongst their 256-peptide signature, one particular peptide - "LRVVWLSGVASG" - was also mentioned in another independent study with similar aims [2] perhaps therefore requiring further research focus. For those who might not be totally au fait with peptide designation, that string of letters is not meant to be pronounced, but rather each letter corresponds to an amino acid making up that particular peptide.

Whilst this is great work and indeed, represents some really quite detailed analysis, the authors caution that the science is not quite there yet when it comes to a 'biological test' for ME/CFS. So: "the heterogenous nature of ME/CFS clinical presentation and the variance natural present amongst control samples means that group labels in the Discovery and Validation Sets are not based on any gold standard." Diagnosis of ME/CFS still remains a point of real contention in various circles (see here) given the variety of diagnostic criteria available. Indeed, some commentators have suggested that the combination of 'ME/CFS' as a unified diagnostic label simply cannot ever exist (see here). The authors further note that: "Even the best research case definitions are often subjective and—in the absence of clear biomarkers—any group of ME/CFS cases likely comprise a heterogeneous set of pathologies."

I'm also minded to suggest that as per the lessons being learned in connection to autism biomarker research for example (see here), one needs to perhaps think about getting different research groups together who are looking at ME/CFS from different angles (see here). Y'know, sort of combining various different biomarker studies looking at various different biological 'angles' and sorta meta-analysing all the collected data to see if a larger, grander, range of variables might provide a more accurate biomarker picture of the condition(s)...

Still, the Günther study represents some good science and good value-for-research-money. It stresses how, by utilising the pretty sophisticated analytical equipment available these days, one can start creeping ever closer to some of the possible biochemistry that underpins ME/CFS (or at least some ME/CFS) and perhaps then also start some conversations centred on what can be done to alleviate symptoms and cure such a devastating illness.

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[1] Günther OP. et al. Immunosignature Analysis of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). Mol Neurobiol. 2018 Oct 8.

[2] Singh S. et al. Humoral Immunity Profiling of Subjects with Myalgic Encephalomyelitis Using a Random Peptide Microarray Differentiates Cases from Controls with High Specificity and Sensitivity. Mol Neurobiol. 2018 Jan;55(1):633-641.

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Helminthic Trichuris Suis Ova vs. placebo for repetitive behaviours in adult autism

The trial results published by Eric Hollander and colleagues [1] were not entirely unexpected. I had previously mentioned their study on the "use of the immunomodulator Trichuris Suis Ova (TSO)" with autism in mind in another post (see here) but, at that time, still awaited the peer-reviewed publication version to appear. I wait no longer.

OK, Trichuris suis (T. suis) is a parasite. It makes its home in the deepest, darkest recesses of other creatures, apparently also having the rather important evolutionary advantage of being able to stay in egg form for quite a long time 'awaiting ingestion'. But just before you turn away John Hurt style (no, I'm not going to link to the 'chest-buster' scene), this particular parasite might not be 'all bad'. I'm specifically talking about some preliminary data suggesting that T. suis *might* have some important immunological effects [2] when ingested in a controlled manner under certain clinical circumstances.

Hollander et al took things one stage further by their insinuation of a link between use of an "immunomodulator" such as T. suis and their study to determine "the effect sizes for TSO vs. placebo on repetitive behaviors, irritability and global functioning in adults with ASD [autism spectrum disorder]." And just before you question the idea that immune function might be something important to some overt behaviour(s), there is other research out there discussing the possibility of such an effect (see here and see here) specifically with autism in mind.

"A 28-week double-blind, randomized two-period crossover study of TSO vs. placebo in 10 ASD adults, ages 17 to 35, was completed, with a 4-week washout between each 12-week period." This was a 'gold-standard' trial design albeit with a very, very small participant group who represented only a specific 'part' of the autism spectrum [3]. The trial was also registered for all to see the proposed hows-and-whys (see here) including the detail: "Have a personal or family history of allergies" as part of the inclusion criteria.

Results: "Differences between treatment groups did not reach statistical significance." This is an important point highlighting how use of T. suis ("the eggs of intestinal helminthes (trichuris suis ova) administered as 2500 ova doses every two weeks") did not translate into statistically significant group differences across measures looking at the social communication aspects of autism for example. I say this bearing in mind that the Hollander study was a cross-over trial too.

But... "Large effect sizes for improvement in repetitive behaviors (d = 1.0), restricted interests (d = 0.82), rigidity (d = 0.79), and irritability (d = 0.78) were observed after 12 weeks of treatment." What this means is that when comparing participants using T. suis vs. their baseline measurements, they seemed to do better on the T. suis portion of the trial across various different types of behaviour. Importantly too we are told that "TSO had only minimal, non-serious side effects" bearing in mind this included various gastrointestinal (GI) side-effects (and knowing that GI issues are already 'a thing' when it comes to autism).

So, there we have it. The results of the first (small scale) clinical trial using Trichuris Suis Ova (TSO) helminthic style with autism in mind. Obviously a lot more research is required before this type of intervention goes anything like 'mainstream'. Alongside there is also the 'acceptability' factor to consider: how many people would actually want to ingest a parasite such as T. suis? Indeed, one of the next courses of study is perhaps to see 'why' such helminthic therapy has the effect that it has on behaviour, and whether such an effect can be replicated in a medicine or other formulation rather than ingesting a parasite?

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[1] Hollander E. et al. Randomized Crossover Feasibility Trial of Helminthic Trichuris Suis Ova vs. Placebo for Repetitive Behaviors in Adult Autism Spectrum Disorder. World J Biol Psychiatry. 2018 Sep 19:1-25.

[2] Jouvin MH. & Kinet JP. Trichuris suis ova: testing a helminth-based therapy as an extension of the hygiene hypothesis. J Allergy Clin Immunol. 2012 Jul;130(1):3-10.

[3] Hollander E. et al. Trichuris Suis Ova (TSO) as an immune-inflammatory treatment for repetitive behaviors in ASD. European Neuropsychopharmacology. 2016; 26: 891.

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Regressive vs. non-regressive autism: limited chemical differences noted

The paper published by Antonio Gomez-Fernandez and colleagues [1] examining whether or not there may be some potentially important biological differences as a function of reported regression vs. no regression in autism provides the blogging fodder today. Not for the first time has the immune system and 'regressive autism' been mentioned in the peer-reviewed science literature (see here and see here), but the current work focuses on the examination of various immune system and other related compounds: in a seemingly well-defined cohort: "Analyses of plasma molecules, such as cathepsin, IL1β, IL6, IL8, MPO, RANTES, MCP, BDNF, PAI NCAM, sICAM, sVCAM and NGF."

"Fifty-four children (45 males and nine females) aged 2-6, who were diagnosed with ASD [autism spectrum disorder], and a control group of 54 typically-developing children of similar ages were selected." Authors relied on quite an extensive battery of assessments looking at behaviour, alongside their use of the DSM-5 diagnostic criteria for autism (see here). Also accompanying physical examination "with a special emphasis on neurological and nutritional status", authors garnered blood samples from participants (overnight fasting) for their immune system and related functioning evaluations.

"The group of ASD children was further divided into two subgroups based on the presence or absence of neurodevelopmental regression during the first two years of life, which was assessed using a five-item questionnaire following the guidelines used by the Autism Diagnostic Interview-Revised (ADI-R) for the evaluation of this process." The ADI-R has been previously discussed on this blog in relation to regression in autism (see here). And just in case you might not be totally convinced that regression can be part of a pathway to autism, here's some more evidence for you (see here)...

Results: "there were 20 children included in the AMR [neurodevelopmental regression] subgroup and 32 in the ANMR [without neurodevelopmental regression] subgroup; two children could not be classified in these subgroups because they were adoptees, allocated by a national adoption agency." Bearing in mind that we cannot rule out any recruitment bias that might have leaned towards including those with regressive autism on the Gomez-Fernandez study, the figure of approaching 40% of their cohort showing such a regressive profile is notable. I'd also draw your attention to the finding that the behavioural profile for the regressive group (AMR) was also significantly different from the non-regressive group (ANMR) insofar as perhaps painting a picture of greater [group] autism severity...

Interestingly, the study did not show too many immune system and other compound differences between those diagnosed with autism and the asymptomatic (for autism) control group. So: "No differences were found between the two groups in terms of the cytokine and adhesion molecule levels studied, except for NGF [nerve growth factor], in which the group of ASD children was found to have twice the plasma levels compared to the control group." NGF is no stranger to autism research, and other studies have come to a similar conclusion [2].

When it came to examining results based on comparing the regressive (AMR) and non-regressive (ANMR) groupings, things got slightly more interesting but again no complicated pattern of difference was noted. So, for the ANMR (non regression) grouping: "lower plasma levels of the NCAM adhesion molecule were detected compared to the levels in the AMR subgroup and the control group. This ANMR group also exhibited higher NGF levels than the typically-developing children, which could indicate an alteration in neuronal development." Again, adhesion molecules have been mentioned in other autism research (see here).

"In conclusion, the results of this study show that there is not a typical profile for the expression of relevant plasma cytokines, adhesion molecules or growth factors in children with ASD compared with that in typically-developing children." OK, there are caveats to the phrasing used by the authors; not least that the participant numbers were quite small in the Gomez-Fernandez study and the idea that within the very heterogeneous autism spectrum, there may be smaller groupings (phenotypes) that perhaps show a tendency to greater immune system and related 'issues' (see here). But there are also some strengths attached to the Gomez-Fernandez study; not least the study "benefits from a careful selection of children of similar ages, as well as the complete diagnosis of ASD with multiple tests, clinical follow-up and associated complementary tests."

Questions still remain. Perhaps an important one is the question around why some children show a regressive pattern of behaviour as part of their path to a diagnosis of autism? Yes, issues such as infection do seem to be part-and-parcel of the clinical profile for some (see here and see here for examples) and perhaps more detailed focus is required in such areas. But much like a group showing the opposite of regressive autism - those who seemed to 'grow out' of autism - currently thought to include as many as one in ten (see here), a wider range of biological as well as psychometric measures are required to help pick out potentially important mechanisms pertinent to the idea that autism is not necessarily 'hard-wired' for all...

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[1] Gomez-Fernandez A. et al. Children With Autism Spectrum Disorder With Regression Exhibit a Different Profile in Plasma Cytokines and Adhesion Molecules Compared to Children Without Such Regression. Front. Pediatr. 2018. September 26.

[2] Dinçel N. et al. Serum nerve growth factor levels in autistic children in Turkish population: a preliminary study. Indian J Med Res. 2013 Dec;138(6):900-3.

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"C-Reactive Protein as a Peripheral Biomarker in Schizophrenia"

The results of the 'updated systematic review' published by Guillaume Fond and colleagues [1] looking at the "relationships between elevated blood C-reactive protein (CRP) levels and schizophrenia (SZ) onset risk, illness characteristics and treatments, cognition and physical health" provides the blogging fodder today.

Fond (a name not unfamiliar to all-things schizophrenia) et al dip into a topic with more than its fair share of research 'uncertainty' (see here and see here for examples) on whether or not C-reactive protein (CRP), a marker of systemic inflammation, shows a connection to schizophrenia. On this particular research occasion, no new data is added to the debate, but rather authors looked at the collected peer-reviewed data (up to November 2017) to see if any 'general opinions' could be discerned from the collected works.

Results: based on over 50 studies included in their review, authors concluded that it was 'reasonable' to assume that high-sensitivity CRP (hs-CRP) may be a marker for 'schizophrenia onset risk'. The caveat to that statement is that CRP is probably not something 'schizophrenia-specific' in terms of elevations of CRP being indicative of a inflammatory state. So increased hs-CRP may well be a risk factor for "increased positive symptoms, cognitive impairment, hypovitaminosis D, microbiota disturbances, cardiovascular and metabolic syndrome risk in SZ subjects, and increased nicotine dependence in SZ smokers."

I'm pretty happy with the Fond results and interpretation as they stand. They suggest that CRP probably does show some sort of connection to schizophrenia and onward, points to an immune system connection to at least some cases (see here and see here). At the same time, they also imply that certain other observations around schizophrenia - such as a link with certain physical health issues (see here) and/or vitamin D deficiency (see here) - probably also contribute to the elevations of CRP noted in relation to cases of schizophrenia. They also imply that moves to reduce levels of CRP in relation to schizophrenia may well have various other 'knock-on' effects on those other risk factors associated with the condition/diagnosis. This 'double hit' effect could be quite useful.

And with that last sentence in mind, and accepting that consistently high levels of CRP are probably good for no-one, the next question: what can we do about elevated CRP levels in relation to schizophrenia and further, the immune system issues also being co-expressed? Lots, is my impression; perhaps also learning from other labels where immune function (and dysfunction) has been noted [2] and intervention is similarly indicated.

And there's more to come from this authorship group on this blog soon...

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[1] Fond G. et al. C-Reactive Protein as a Peripheral Biomarker in Schizophrenia. An Updated Systematic Review. Front. Psychiatry. 2018. Aug 23.

[2] Marchezan J. et al. Immunological Dysfunction in Autism Spectrum Disorder: A Potential Target for Therapy. Neuroimmunomodulation. 2018 Sep 5:1-20.

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Results "provides support for the possibility that some children with ASD may benefit from IVIG": but do they?

I had high hopes for the paper by Kathleen Connery and colleagues [1] titled: "Intravenous immunoglobulin for the treatment of autoimmune encephalopathy in children with autism." It talked about screening for various "brain-targeted autoantibodies" under the label of autoimmune encephalopathy (AIE) and the use of intravenous immunoglobulin (IVIG) as an intervention, all in the context of autism. Important and timely issues.

Unfortunately, after having read the paper a few times, high hopes dissipated somewhat in terms of some of the methodology employed and the 'support' provided by some of the test results obtained for using something like IVIG...

AIE covers quite a bit of diagnostic ground. First and foremost, it represents a disease where a person's own immune system starts to recognise 'self' as 'other' and starts attacking healthy brain cells, leading to inflammation of the brain. AIE is a serious condition that in some cases leads to death. Other symptom manifestations include seizures accompanied by various cognitive, behavioural and psychiatric consequences. In short, it is not something that anyone would want. It also requires prompt identification and treatment. If you need a good example of this, type in the words 'brain on fire' into your search engine and read on...

I've talked quite a bit on this blog about encephalitis (brain inflammation) in the context of autism (see here and see here for examples). Indeed, some big names in autism research are coming around the idea that brain inflammation in the context of some autism is a very real concept (see here). Although correlation does not necessarily equal causation, the coincidence of autistic signs and symptoms appearing alongside cases of encephalitis is hard to ignore. Particularly when some authors have talked about an 'autistic regression' [2] in the context for example, of N‐methyl‐d‐aspartate receptor antibodies (NMDAR‐Ab) encephalitis. In the same breath, some of those peer-reviewed documented cases of encephalitis and autism co-occurring have also talked about treatment. And in some cases, the treatment of choice was immunotherapy including IVIG.

So, back to the Connery paper. Some 80 children diagnosed with an autism spectrum disorder (ASD) were included for study. They were all evaluated at a "multispecialty clinic for AIE." They were (variably) screened for various autoantibody markers "by several panels." This included "antineuronal nuclear, anti-glial nuclear, Purkinje cytoplasmic, P/Q and N-type calcium, and VGKC antibodies as well as GAD65, AMPA, NMDA, and GABA-B receptor antibodies" headed under the term 'Paraneoplastic panel'. Something called the 'Cunningham panel' was also undertaken: "antidopamine D1 receptor (D1R), antidopamine D2L receptor (D2R), anti-lysoganglioside GM1, anti-tubulin, CaMKII." I believe that one of the authors on the Connery paper was also an inventor of this Cunningham panel. I should also reiterate that participants were 'variably' screened using the different panels. What this means is that not every child received the total panel of screening available

Results: perhaps most importantly we are told that within this cohort: "very few demonstrated autoantibodies usually associated with AIE in children." Having already focused in on NMDA receptor encephalitis, researchers observed that none of their cohort (who were tested) showed a positive result for NMDA receptor autoantibodies: "NMDA receptor autoantibodies were negative in all of the 34 patients in which it was tested."

Further: Using pre-defined criteria for being positive, "the Cunningham panel was positive in 44 (57%) of the 77 patients in which it was performed." I don't know too much about the Cunningham panel outside of what the company who offer it say about it on their website. I did happen upon one study [2] which looked at its use for potentially diagnosing Pediatric Acute Neuropsychiatric Syndrome (PANS) and concluded that 'must do better' was the best opinion to be given; also observing that "pathological Cunningham Panel results were present in 18 of 21 healthy controls." To provide some balance, there was some further correspondence linked to the Hesselmark/Bejerot paper (see here) regarding incorrect methodology being used. But even after this, the authors still concluded that: "Our results indicate that the [Cunningham] panel does not contribute to correct diagnosis in a clinical setting."

No mind, IVIG was eventually recommended for 49 participants (60% of the cohort). Those autoantibody panels were not however, the only route to receiving an IVIG recommendation, as authors also mention that "patients with severe behavioral or medical symptoms including drug-resistance epilepsy and/or immunodeficiency were considered candidates for IVIG treatment." In all, results are reported for 31 children who received IVIG under the watchful eye of the authors' care team.

So what happened when IVIG was given? Well, this is perhaps also where the Connery paper has perhaps over-stretched itself in terms of what results are presented. Various cognitive and behavioural outcomes are reported on as a function of 'before' and 'after' use of IVIG. The authors for example, talk about use of the SRS - "for measuring the social aspects of ASD" - and observed evidence of statistically significant differences. But one needs to bear in mind that this was not a blinded trial and therefore to say that any gains were present as a direct result of IVIG treatment is pushing it a little. I'm also left slightly unimpressed with the idea of 'best responders' on the basis of such immunological and behavioural results too on the basis of this study alone. At least however, the authors don't shy away from the quite frequently reported adverse effects *correlating* with IVIG use: "Sixty-five percent (20/31) of patients reported adverse effects, most commonly headaches and vomiting" and the need for caution when considering IVIG in the context of some autism.

As I said, I did initially have high hopes for the Connery results and indeed, there are some important research directions they raise which need appropriate follow-up. One of them is the possibility that PANS *might* be something not uncommon to the autism spectrum (see here). I did however come away less than impressed with elements of the design of their study and some of their interpretations of their findings. I don't want to poo-poo the idea that some manifestations of autism might be linked to the presence of AIE or that IVIG might be an intervention option for some. Unfortunately however, the Connery paper does not really provide the ideal evidence for either concept, which is a pity...

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[1] Connery K. et al. Intravenous immunoglobulin for the treatment of autoimmune encephalopathy in children with autism. Transl Psychiatry. 2018 Aug 10;8(1):148.

[2] Hesselmark E. & Bejerot S. Biomarkers for diagnosis of Pediatric Acute Neuropsychiatric Syndrome (PANS) - Sensitivity and specificity of the Cunningham Panel. J Neuroimmunol. 2017 Nov 15;312:31-37.

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