rexresearch.com
Rosa KRAJMALNIK-BROWN,
et al: Fecal Transplants vs
Autism
https://www.rt.com/news/456148-fecal-transplants-autism-breakthrough/
Fecal transplants yield MASSIVE
breakthrough for child autism, 50% reduction in severity
(VIDEO)
Scientists are celebrating a “world-first discovery” which shows
the “highest improvement” in child autism patients, using fecal
transplants to massively curtail symptoms and greatly reduce
suffering.
The results of the initial study involving 18 children show great
promise: 83 percent of the children had “severe” autism symptoms,
but just two years later, only 17 percent had “moderate” symptoms,
while 44 percent fell below the threshold for “mild” autism.
The team recorded a roughly 45-percent drop in language, social,
and behavioural issues in the children over the course of the
study.
The initial success of the microbiota or ‘fecal transfer’ therapy
adds further weight to the theory this, and many other,
neurological conditions may be strongly connected to the gut
rather than the brain.
“We are finding a very strong connection between the microbes that
live in our intestines and signals that travel to the brain,” Dr.
Rosa Krajmalnik-Brown, a microbiologist at Arizona State
University who jointly led the study, said, adding that, “Two
years later, the children are doing even better, which is
amazing.”
In the US, one in every 59 children is diagnosed with some form of
autism, which is a spectrum disorder, a vast increase in diagnosis
from just one in every 150 in 2000. This means that half a million
people on the autism spectrum will become adults in the next
decade, “a swelling tide for which the country is unprepared,”
according to the researchers.
In children with autism, gastrointestinal symptoms such as
constipation and diarrhoea can cause irritability, decreased
attention span, and negatively impact behaviour, exacerbating
other symptoms and making treatment and condition management far
more difficult.
The regimen consists of pre-treatment with a bowel cleanse,
administering a stomach acid suppressant and fecal transplants for
between seven and eight weeks. The ‘donation’ of more diverse gut
bacteria greatly boosts overall health and wellbeing in the
patients.
Much larger trials are required before the treatment is officially
approved by the US Food and Drug Administration.
The treatment was originally pioneered by Dr. Thomas Borody, an
Australian gastroenterologist, who has hailed the results as a
significant breakthrough.
“This is a world-first discovery... I would call it the highest
improvement in a cohort that anyone has achieved for autism
symptoms,” he said.
https://biodesign.asu.edu/news/autism-symptoms-reduced-nearly-50-two-years-after-fecal-transplant
Autism symptoms reduced nearly 50% two
years after fecal transplant
According to the Centers for Disease Control and Prevention, about
one in every 59 children in the U.S. is diagnosed with autism, up
from one in every 150 in 2000. They report that “about half a
million people on the autism spectrum will become adults over the
next decade, a swelling tide for which the country is unprepared.”
The apparent rise in autism spectrum disorder (ASD) and its
stubborn resistance to treatment has spurred a legion of
researchers to enter the field and explore the disability in
innovative ways.
Currently, effective treatments for ASD include behavioral
therapy, speech and social therapy, psychiatric medications, and
dietary and nutritional approaches. However, no medical treatments
have been approved to treat core symptoms of ASD such as social
communication difficulties and repetitive behaviors.
One promising avenue of autism research involves the gut
microbiome, which is the collection of microbes that lives in our
intestines and helps us in many ways including digestion of our
food, training our immune system and preventing overgrowth of
harmful bacteria. Recent research suggests our gut microbiomes
also affect brain communication and neurological health.
Worldwide, interest is growing in the idea that changes in normal
gut microbiota may be responsible for triggering a vast range of
diseases.
In a new study, “Long-term benefit of Microbiota Transfer Therapy
in Autism Symptoms and Gut Microbiota,” published in Scientific
Reports, Arizona State University researchers Rosa
Krajmalnik-Brown, Ph.D., James Adams, Ph.D, and lead author
Dae-Wook Kang, Ph.D, demonstrate long-term beneficial effects for
children diagnosed with ASD through a revolutionary technique
known as Microbiota Transfer Therapy (MTT), a special type of
fecal transplant originally pioneered by Dr. Thomas Borody, an
Australian gastroenterologist. Remarkably, improvements in gut
health and autism symptoms appear to persist long after treatment.
At two years post-treatment, most of the initial improvements in
gut symptoms remained. In addition, parents reported a slow steady
reduction of ASD symptoms during treatment and over the next two
years. A professional evaluator found a 45% reduction in core ASD
symptoms (language, social interaction and behavior) at two years
post-treatment compared to before treatment began.
“We are finding a very strong connection between the microbes that
live in our intestines and signals that travel to the brain,” said
Krajmalnik-Brown, a professor at the Biodesign Swette Center for
Environmental Biotechnology at the Biodesign Institute and ASU’s
School for Sustainable Engineering and the Built Environment. “Two
years later, the children are doing even better, which is
amazing.”
“Many kids with autism have gastrointestinal problems, and some
studies, including ours, have found that those children also have
worse autism-related symptoms,” said Krajmalnik-Brown. “In many
cases, when you are able to treat those gastrointestinal problems,
their behavior improves.”
Roughly 30-50% of all people with autism have chronic
gastrointestinal (GI) problems, primarily constipation and/or
diarrhea that can last for many years. That chronic discomfort and
pain can cause irritability, decreased attention and learning, and
negatively impact behavior.
An earlier study with only vancomycin (an antibiotic) had found
major temporary improvements in GI and autism symptoms, but the
benefits were lost a few weeks after treatment stopped despite use
of over-the-counter probiotics.
So, the question at hand was what’s going on in the gut, and how
does it affect both physical and behavioral symptoms of autism,
and how can we develop a long-lasting treatment?
Krajmalnik-Brown, Kang and Adams have shown that by transferring
healthy microbiota to individuals lacking certain gut bacteria, it
is possible to “donate” a more diverse set of bacteria into the
patient and improve gut health.
In Australia, Fecal Microbiota Transplantation (FMT) was initially
developed by Borody. At his Centre for Digestive Diseases in
Sydney, Borody has overseen more than 18,000 FMTs for various
disorders since 1987. He pioneered in Australia the use of FMT for
colitis and Clostridium difficile infection, and was the first to
use oral FMT to treat children with ASD. Only one dose of FMT is
usually enough to cure C. Difficile infections, but his patients
with autism were far harder to treat. He discovered that three
months of daily FMT was required to treat his autism patients, but
eventually resulted in significant improvements in both GI and
autism symptoms.
Based on his experience with his patients, Borody led the design
of the clinical treatment used at ASU for this study. The MTT
approach involves 10 weeks of treatment, including pre-treatment
with vancomycin, a bowel cleanse, a stomach acid suppressant, and
fecal microbiota transfer daily for seven to eight weeks.
The initial open-label study, led by Krajmalnik-Brown and Adams,
and published in the journal Microbiome in 2017, concluded that
“this exploratory, extended-duration treatment protocol thus
appears to be a promising approach to alter the gut microbiome and
improve GI and behavioral symptoms of ASD. Improvements in GI
symptoms, ASD symptoms, and the microbiome all persisted for at
least eight weeks after treatment ended, suggesting a long-term
impact.” The present study now shows the benefits are
extended beyond eight weeks to at least two years post-treatment.
The ASU team compared differences in the microbiome of children
with autism compared to typically developing children. At the
start of the study, children with autism were found to have lower
diversity in their respective gut microbes and were depleted of
certain strains of helpful bacteria, such as Bifidobacteria and
Prevotella. “Kids with autism are lacking important beneficial
bacteria, and have fewer options in the bacterial menu of
important functions that bacteria provide to the gut than
typically developing kids,” Krajmalnik-Brown said.
FMT treatment substantially increased microbial diversity and the
presence of helpful bacteria in the gut, such as Bifidobacteria
and Prevotella. After two years, diversity was even higher and the
presence of beneficial microbes remained.
“We originally hypothesized that our therapy would be efficient to
transform the dysbiotic gut microbiome toward a healthy one. In
our original paper in 2017, we reported an increase in gut
diversity together with beneficial bacteria after MTT, and after
two years, we observed diversity was even higher and the presence
of beneficial microbes remained,” Kang said. He added that this
may be one of the reasons for success in improving the gut health,
but further mechanistic studies are warranted to define specific
roles of gut microbes in the context of autism.
The work done at ASU is not only about treating patients but also
about learning from the treatment in order to develop better
formulations and optimize dosing.
“Understanding which microbes and chemicals produced by the
microbes are driving these behavioral changes is at the heart of
our work,” Krajmalnik-Brown said. The team’s new publication
reports that the study demonstrated that two years after treatment
stopped the participants still had an average of a 58% reduction
in GI symptoms compared to baseline. In addition, the parents of
most participants reported “a slow but steady improvement in core
ASD symptoms.”
“Every family completed the study, and every family returned two
years later for a follow-up evaluation,” said Adams, citing the
families’ dedication to the research. “The treatment was generally
well-tolerated with minimal adverse effects.”
"This is a world-first discovery that when we treated the gut
bacteria in these children during our clinical trial two years ago
to reset their microbiome with FMT, positive results are still
continuing to be improving two years from the original treatments.
I would call it the highest improvement in a cohort that anyone
has achieved for autism symptoms,” said Borody.
Professional evaluation revealed a 45% decrease in ASD symptoms
compared to baseline. Researchers note that although there may be
some placebo effect, much of that effect appears to be real.
At the start of the study, 83% of participants were rated as
“severe” autism. At the end of the study, only 17% were
“severe,” 39% were “mild/moderate,” and 44% were below the cut-off
for mild ASD.
Greg Caporaso, at Northern Arizona University, a leading expert in
microbiome data science and a co-author on these studies, helped
to analyze the microbiome data to better understand bacterial
changes as a result of MTT.
“Drs. Krajmalnik-Brown, Kang and I are excited about the results,
but we want to caution the public that we need larger clinical
trials for this to become an FDA-approved treatment,” said Adams.
Professional expertise is required for safe and effective
treatment.
MTT improves GI distress by introducing key strains of beneficial
bacteria and helping to raise levels of biodiversity within the
gut, boosting health overall.
Adams has both professional and personal reasons for doggedly
pursuing ways to help children with autism because he knows the
situation first-hand. His daughter was diagnosed with autism just
before her third birthday. Adams, a President’s Professor at
ASU’s School for Engineering of Matter, Transport and Energy, and
the chair of Materials Sciences, is also president of the Autism
Society of Greater Phoenix, the largest parent support group in
Arizona.
“Dr. James Adams is the reason why I started working on autism,”
Krajmalnik-Brown said. “I had the methods to do all of the
measurements and assessments in the microbiome part of the work,
and he had the autism knowledge.”
Adams recruited patients, supervised clinical work and ASD
assessments, and guided the patients through the trials, and
Krajmalnik-Brown led the microbiome evaluations and helped plan
the study.
All of the participants in the study exhibited chronic GI symptoms
from infancy, including chronic constipation and/or chronic
diarrhea. The treatment benefits extended beyond their physical
symptoms, even causing some parents to note how much their
children’s behavior had improved over time.
“It is very unusual to see steady gradual improvement after the
conclusion of any treatment,” said Adams. “We only conducted the
long-term follow-up study after several families told us that
their child was continuing to improve significantly.”
Krajmalnik-Brown stated that the data suggests that the MTT
intervention transformed the gut environment into a healthier
status, leading to long-term benefit on both GI and ASD symptoms.
Adams said many of the participants in the trial shared common
traits, including birth by C-section, reduced breastfeeding,
increased antibiotics, and low fiber intake by the mother and
child, all of which lead to limited biodiversity in their gut
bacteria. Due to the open label nature of the study and the small
sample size used, more research is needed in order to verify the
usefulness of MTT as a therapeutic.
The initial study involved a “first-generation” estimate as to
optimal dose and duration of treatment, and it was enough for 90%
of the children to have substantial benefit. The team is now
working on optimizing the dosing and duration to try to improve
benefits even more, and to determine if booster doses may be
needed in some cases.
Krajmalnik-Brown and Adams are working now on a larger
placebo-controlled trial in adults with ASD to verify their
results. More information on that study is available at
autism.asu.edu. They also hope to do another study for children
with ASD pending future funding...
https://www.youtube.com/watch?v=UEOtCT8cohE
The Gut Microbiome: Opening new
possibilities for autism treatment
Professors Rosa Krajmalnik-Brown and James Adams discuss their
research that may change the way we treat symptoms of autism in
the future.
https://www.nature.com/articles/s41598-019-42183-0
Scientific Reports, volume 9, Article number: 5821
(2019)
Long-term benefit of Microbiota Transfer
Therapy on autism symptoms and gut microbiota
Dae-Wook Kang, James B. Adams, Devon M.
Coleman, Elena L. Pollard, Juan Maldonado, Sharon
McDonough-Means, J. Gregory Caporaso & Rosa
Krajmalnik-Brown
Abstract
Many studies have reported abnormal gut microbiota in individuals
with Autism Spectrum Disorders (ASD), suggesting a link between
gut microbiome and autism-like behaviors. Modifying the gut
microbiome is a potential route to improve gastrointestinal (GI)
and behavioral symptoms in children with ASD, and fecal microbiota
transplant could transform the dysbiotic gut microbiome toward a
healthy one by delivering a large number of commensal microbes
from a healthy donor. We previously performed an open-label trial
of Microbiota Transfer Therapy (MTT) that combined antibiotics, a
bowel cleanse, a stomach-acid suppressant, and fecal microbiota
transplant, and observed significant improvements in GI symptoms,
autism-related symptoms, and gut microbiota. Here, we report on a
follow-up with the same 18 participants two years after treatment
was completed. Notably, most improvements in GI symptoms were
maintained, and autism-related symptoms improved even more after
the end of treatment. Important changes in gut microbiota at the
end of treatment remained at follow-up, including significant
increases in bacterial diversity and relative abundances of
Bifidobacteria and Prevotella. Our observations demonstrate the
long-term safety and efficacy of MTT as a potential therapy to
treat children with ASD who have GI problems, and warrant a
double-blind, placebo-controlled trial in the future.
Introduction
The human gut and brain interact in complex ways, and abnormal
conditions in the gut may predispose individuals to
neurodevelopmental disorders1,2. Individuals with Autism Spectrum
Disorders (ASD)3, Parkinson’s disease4, and Alzheimer’s disease5,
for example, have been known to experience chronic
gastrointestinal (GI) symptoms as a common co-occurring medical
condition, suggesting the presence of a gut-brain axis. Hallmayer
et al.6 investigated 192 twin pairs and found that both genetic
and environmental factors contribute to the etiology of ASD. The
gut microbiome represents an important environmental factor that
may exert an influence on symptoms, and a growing number of
research groups have observed that children with ASD have
distinctive gut microbiomes compared to neurotypical
children7,8,9,10,11. Moreover, multiple mouse studies have
reported that gut microbes and their metabolites can impact
behavior through the gut-brain axis, including for ASD12,13,14.
Effective treatments for ASD include behavioral therapy, speech
and social therapy, and dietary/nutritional/medical treatments,
but no medical treatment has been approved to treat core symptoms
of ASD15, such as social communication difficulties and repetitive
behaviors. Considering the link between the gut and brain,
modulating the gut microbiome by antibiotics, probiotics,
prebiotics, and/or fecal microbiota transplant (FMT) could be a
viable therapeutic option. In FMT, a large diversity and number of
commensal microbes from a healthy donor are used to transform a
dysbiotic gut microbiome into a healthy microbiome. In fact, FMT
is the most effective therapy to treat recurrent Clostridium
difficile infection16 and has shown varying levels of success for
treating other GI disorders17, which has drawn attention to the
method for use beyond GI-associated disorders18. Previously, we
performed a pioneering open-label modified-FMT trial with an
intensive combination called Microbial Transfer Therapy (MTT)
consisting of two-week vancomycin treatment followed by a bowel
cleanse and then high dose FMT for 1–2 days and 7–8 weeks of daily
maintenance doses along with a stomach-acid suppressant,
administered to children with ASD and chronic gastrointestinal
problems19. After this 10-week MTT treatment and an eight-week
follow-up observation period (18 weeks in total), we observed an
80% reduction in GI symptoms and a slow but steady improvement in
core ASD symptoms. At the same time, we learned that gut microbial
diversity, including potentially beneficial microbes,
significantly increased after MTT19. Two years after this original
clinical trial was completed, we re-evaluated the participants to
determine whether observed improvements in behavior and GI
symptoms persisted, and to ascertain the long-term impact of MTT
on the gut microbiome of the study participants.
Results and Discussion
Improvements in GI and ASD symptoms remained two years
after the MTT stopped
Two years after the MTT was completed, we invited the 18 original
subjects in our treatment group to participate in a follow-up
study, and all provided informed consent. We performed the same GI
and behavior tests that we employed previously19. 12 of 18
participants made some changes to their medication, diet, or
nutritional supplements, but these changes were well documented
and were mostly minor (Supplementary Table S1). We note that due
to the open-label nature of this initial trial, all of the
assessments are subject to placebo effect, however the long-term
improvements we observed here are promising. Two years after
treatment, most participants reported GI symptoms remaining
improved compared to baseline (Fig. 1a and Supplementary Fig. S1).
The improvement was on average 58% reduction in Gastrointestinal
Symptom Rating Scale (GSRS) and 26% reduction in % days of
abnormal stools (Daily Stool Record or DSR) relative to baseline,
and this result is similar to what we observed at the end of
treatment. The improvement in GI symptoms was observed for all
sub-categories of GSRS (abdominal pain, indigestion, diarrhea, and
constipation, Supplementary Fig. S2a) as well as for all
sub-categories of DSR (no stool, hard stool, and soft/liquid
stool, Supplementary Fig. S2b), although the degree of improvement
on indigestion symptom (a sub-category of GSRS) was reduced after
2 years compared with weeks 10 and 18. This achievement is
notable, because all 18 participants reported that they had had
chronic GI problems (chronic constipation and/or diarrhea) since
infancy, without any period of normal GI health (Supplementary
Table S2). The families generally reported that ASD-related
symptoms had slowly, steadily improved since week 18 of the Phase
1 trial, and this was consistent with the data reported in Fig.
1b–f. Based on the Childhood Autism Rating Scale (CARS) rated by a
professional evaluator, the severity of ASD at the two-year
follow-up was 47% lower than baseline (Fig. 1b), compared to 23%
lower at the end of week 10. At the beginning of the open-label
trial, 83% of participants rated in the severe ASD diagnosis per
the CARS (Fig. 2a). At the two-year follow-up, only 17% were rated
as severe, 39% were in the mild to moderate range, and 44% of
participants were below the ASD diagnostic cut-off scores (Fig.
2a). The parent-rated Social Responsiveness Scale (SRS) assessment
revealed that 89% of participants were in the severe range at the
beginning of the trial, but the percentile dropped to 47% at the
two-year follow-up (Fig. 2b), with 35% in the mild/moderate range
and 18% below the cut-off for ASD. For the parent-rated Aberrant
Behavior Checklist (ABC), total scores continued to improve, and
were 35% lower relative to baseline (versus 24% lower at the end
of treatment, relative to baseline; Fig. 1d). The Parent Global
Impressions-III (PGI-III) scores remained similar to the scores at
the end of treatment (week 10) of the open-label (Fig. 1e). The
Vineland Adaptive Behavior Scale (VABS) equivalent age continued
to improve (Fig. 1f), although not as quickly as during the
treatment, resulting in an increase of 2.5 years over 2 years,
which is much faster than typical for the ASD population, whose
developmental age was only 49% of their physical age at the start
of this study. Moreover, we observed improvement in behaviors in
most sub-categories (Supplementary Figs S2c,d, and S3 for ABC,
SRS, and VABS, respectively).
Overall, the most substantial improvements observed were on the
CARS assessments, which was conducted by a professional evaluator
and is less susceptible to placebo-effect20. CARS is a stable and
consistent diagnostic tool with high predictive validity21 and has
been used to evaluate participants before and after therapeutic
interventions in multiple studies20,22,23. For the follow up CARS,
the evaluator collected current information based on each
question’s unique criteria. After the interview was complete for
each question, the evaluator reviewed the information initially
collected at baseline and used it for calibrating the final
evaluation.
Improvements in GI and ASD symptoms were significantly
correlated
We performed statistical analyses to assess whether improvements
in GI and ASD severity were correlated. As shown in Fig. 2c–e,
percentage changes in CARS, SRS, and ABC scores were positively
correlated with percent changes in GSRS scores (Spearman
correlation test, 2-tailed p?<?0.005 and r?>?0.7), implying
that GI relief provided by MTT may ameliorate behavioral severity
in children with ASD, or vice versa, or that both may be similarly
impacted by another factor. Another GI assessment, DSR, however,
showed that there was no significant correlation. Although the
direction of the influence is not clear, a potential clinical link
between GI and behavior severity is consistent with what previous
studies have reported24,25.
ASD fecal bacterial diversity was higher two years after the MTT
stopped
16 out of 18 original ASD participants provided an additional
fecal sample two years after the open-label trial. Based on 16S
ribosomal RNA (rRNA) gene amplicon sequencing analysis, most
participants maintained higher gut microbiota diversity two years
after treatment relative to baseline. Interestingly, for many
individuals, the bacterial diversity was higher at two years than
at the week 18 follow up as measured by Faith’s Phylogenetic
Diversity (Fig. 3a and Supplementary Fig. S4a) and Observed OTUs
(Supplementary Fig. S5a). Considering low gut bacterial diversity
in individuals with ASD26 and other human disorders27,28,29, an
increase in diversity after MTT may reflect that MTT intervention
successfully transformed gut environment into a healthier status
and led to a long-term benefit on GI and behavior symptoms
Upon completion of the original MTT treatment, we observed that
the unweighted UniFrac distance30 between the gut microbiota of
MTT recipients and their corresponding donors was smaller than
before treatment, suggesting some engraftment of the donor
microbiome into the recipients by MTT19. Interestingly, two years
after the trial, the recipients were as different from the donor
microbiome as they were pre-treatment as measured by unweighted
UniFrac distance (Fig. 3b, Supplementary Fig. S4b) and several
other metrics of community dissimilarity (Supplementary Fig.
S5b–e). This suggests that the recipients didn’t retain completely
the donated microbiome, but rather retained some features of it
such as increased overall diversity, and increase in some
important microbes such as Prevotella, while finding a new state.
Bifidobacterium and Prevotella relative abundances remained higher
in feces of participants with ASD two-years after MTT stopped
Three taxa that were noticeably enhanced in MTT recipients at the
conclusion of the original clinical trial19 were revisited during
the two-year follow-up. Notably, compared to baseline, median
relative abundances of Bifidobacteria and Prevotella increased
4-fold and 712-fold at week 10, and 5-fold and 84-fold at two
years, respectively (Fig. 4a,b). Desulfobivrio relative abundance
decreased since week 18 (Fig. 4c), but at the two-year follow-up
was still marginally higher compared to baseline (two-tailed
Wilcoxon signed-rank test, p?=?0.07) and higher than neurotypical
controls (two-tailed Mann-Whitney U test, p?<?0.05). An
increase in Prevotella after MTT is noteworthy, since its lower
abundance in feces of children with ASD compared with neurotypical
children has been confirmed in two different cohorts26,31. A
recent study also found reduced levels of Prevotella in the oral
microbiome of children with ASD32. Prevotella may be involved in
butyrate production33, a key nutrient for the intestinal
epithelial cells34. In addition, its co-occurrence with
Desulfovibrio may reflect a synergistic advantage to outcompete
other commensal microbes that utilize mucin as nutrients35,
although more research is needed on how their ecological niche in
mucin desulfation could contribute to an integrity of gut
epithelial cells36 as well as to the improvement on GI and
behavior symptoms we observed. Further mechanistic studies with
multi-omic approaches are warranted to define the roles of
Prevotella and Desulfovibrio in the context of autism.
To the best of our knowledge, long-term follow-up studies are rare
for medical treatment of individuals with ASD. In treatments with
vancomycin37 or phytochemical sulforaphane38, benefits were lost
within two or four weeks, respectively, of the treatments being
discontinued. Thus, the long-term benefits observed here two years
after MTT stopped are very encouraging, and MTT-driven gut
microbiota transformation seems robust and long-lasting for the
treatment of ASD. Despite steady and continuous improvement in
behaviors over two years, we must underscore that the original
clinical trial and current follow-up study are open-label trials
without a control for placebo effect. Autism symptoms are
relatively stable over time without a major intervention: for
example, a trajectory study with 345 children with ASD showed that
more than 80% of participants with ASD retained unexpectedly
stable core symptoms severity over 8 to 12 years39. The VABS
observations indicate that the improvements in adaptive behaviors
observed here were substantially more than expected for children
with ASD over two years. A limitation of this study is that 12 out
of 18 participants made one or more changes to their medications,
nutritional supplements, and diets between the end of the original
MTT trial and the two-year follow-up since the treatment stopped
(Supplementary Table S1). As described in detail in the methods
section, participants were asked to rate the perceived
effectiveness on GI and ASD symptoms (on a scale of 0–4) caused by
changes in medications, diet, or nutritional supplements. Although
the scale on the perceived effectiveness is still subjective and
difficult to interpret, low scores received (1.1 for GI and 0.8
for ASD symptoms) suggest that these treatments on average could
have only “slight effect”. Thus, it appears that most of the
changes observed were probably due to the MTT, although we still
need follow-up studies to understand whether the improvement by
MTT were solely from vancomycin, MoviPrep, Prilosec, Standardized
Human Gut Microbiota (SHGM), or a combination of these individual
factors. For example, some participants in our study could have GI
symptoms that were acid-peptic in nature, and their improvements
on GI symptoms might be solely attributed to the administration of
stomach-acid suppressant (Prilosec)40. We hypothesize that MTT may
also be beneficial for children with ASD who do not have obvious
GI symptoms but have low diversity of gut bacteria, as our
previous study26 found that most children with ASD had low gut
bacterial diversity, regardless of whether they have GI problems.
Here, we also would like to address a potential study limitation
interpreting the improvement on GI symptoms after MTT, since these
heterogeneous GI symptoms could reflect a wide range of underlying
etiological GI pathologies. Although we reviewed medical histories
to exclude children with known gastrointestinal diagnoses (such as
ulcerative colitis, Crohn’s Disease, celiac disease, eosinophilic
gastritis, or similar conditions)19, we did not conduct additional
GI diagnostic evaluations, which is a limitation of this study.
Thus, we want to underscore need of follow-up studies embracing
more thorough examination of participants’ GI pathologies in order
to better understand effectiveness of MTT.
Conclusions
In summary, all 18 participants with ASD were re-evaluated two
years after MTT treatment stopped, and we observed significant
improvements both in GI and behavior symptoms as compared with
baseline measurements collected at the beginning of the original
open-label trial. GI benefits were mostly maintained from the end
of treatment, and autism symptoms were reported to have improved
significantly since the end of treatment. Changes in gut
microbiota persisted at two years, including in overall community
diversity and relative abundances of Bifidobacteria and
Prevotella. These encouraging observations demonstrate that the
intensive MTT intervention is a promising therapy for treating
children with ASD who have GI problems. We recommend future
research including double-blind, placebo-controlled randomized
trials with a larger cohort...