Gut Histopathology and other Abnormalities in Autism |
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Symptomatic changesThere has been great argument as to the gastrointestinal (GI) clinical changes that have been considered. One of the problems is that many of the reports by parents were originally considered to be due to psychological changes rather than anything physical. Between 10% and 40% (or greater) of autistic children are considered to have chronic non-specific GI symptoms. Specific Changes. Histopathology: The change in science of autism A few hard working but determined researchers in the field
had created the literature until the reports by the group in London showed
that there were regular physical changes could be shown in the gut wall of symptomatic
children. Following this the amount of
research into autism throughout the world multiplied in many directions, even
though the |
Staining of a
biopsy of the gut wall in autism.
Mucosal cells are blue and the darker cells between the mucosal lines are
areas of the villus in which a greater amount of inflammation is present as
indicated by Class II antigen. |
It
would be ethically difficult to carry out gut biopsies on asymptomatic
children, because and element of risk was involved. As such commonly the only autistic children
that could be tested for gut histopathological changes were ones with
symptomatic changes. Also, controls
would be difficult to find and match for their age, often only resulting from
biopsies taken for other symptoms or conditions or post mortems.
The
statement at a press conference in 1998 that there was a physical difference
between GI symptomatic autistic children and controls was such a surprise and the
possibility that this was associated with MMR vaccine, led to a determination
by the UK Government that this could not be so.
Pressure was put to withdraw the findings but, as they were what the
researchers had found, they were not withdrawn, merely the statement of
involvement with MMR. Several years
(and to some degree this still continues) of denial of the histopathology has
led to research problems, but, as this
is now being repeated elsewhere this appears to be largely accepted.
The
appearance under H and E stain was of a non-specific lymphonodular hyperplasia
and that appeared to alter the surface appearance of the gut wall because of
the hyperplasia underneath it. Attempts
to assess the lymphoid cells, the production of cytokines showed, the basal membrane and other factors
suggested that this was not a classical IBD but rather a separate
condition. Biopsies were generally
taken from the large bowel but samples taken from the duodenum and jejunum also
showed changes indicating an inflammatory change, with increased turnover of
cells. There are many examples of the
appearance as histopathology of the biopsies: see links
or Thoughtful
House which has a good description of what has been found.
Wakefield
AJ, Murch SH, Anthony A, Linnell J, Casson DM, Malik M, Berelowitz M, Dhillon
AP, Thomson MA, Harvey P, Valentine A, Davies SE, Walker-Smith JA. Ileal-lymphoid-nodular hyperplasia, non-specific
colitis, and pervasive developmental disorder in children. Lancet. 1998 Feb 28;351(9103):637-41. (They found this in all 12 of the cases of
autism with chronic gut problems. They
could state that this was odd compared to other cases and stated that the work
should be done again with major control numbers)
White JF. Intestinal
pathophysiology in autism. Exp
Biol Med (Maywood). 2003 Jun;228(6):639-49.
(a review of the pathology seen from the gut in autism and how this may
be a cause of the clinical syndrome).
Diagram 2.
(Left) Biopsy of a villus in autism with a fluorescent stain (red) of
cytokine C1q suggesting that this is created in adequately large amounts to
produce this effect, which is much greater than that seen in a control. 
Diagram 3. (Right) View of terminal ileum as shown through
the endoscope. You can see the lumps in
the surface that might turn out to be lymphoid hyperplasia under the mucosa.
.Ashwood P, Anthony A, Torrente F, Wakefield AJ. Spontaneous mucosal lymphocyte cytokine profiles in children with autism and gastrointestinal symptoms: mucosal immune activation and reduced counter regulatory interleukin-10. J Clin Immunol. 2004 Nov;24(6):664-73. There is a consistent profile of CD3+ lymphocyte cytokines in the small and large intestinal mucosa of these ASD children, involving increased pro-inflammatory and decreased regulatory activities.
Horvath K, Papadimitriou JC, Rabsztyn A, Drachenberg C, Tildon JT. Gastrointestinal abnormalities in children with autistic disorder. J Pediatr. 1999 Nov;135(5):559-63
Horvath
K, Perman JA. Autistic disorder
and gastrointestinal disease. Curr Opin Pediatr. 2002 Oct;14(5):583-7.
Review (discusses the chronic gut symptoms and the histopathology). (he did
more work on the small bowel)
Horvath K, Perman JA. Autism and
gastrointestinal symptoms. Curr Gastroenterol Rep. 2002 Jun;4(3):251-8.
Review. (discusses the chronic gut symptoms and the histopathology,
particularly of the small bowel).
Horvath
K et al, Gastrointestinal abnormalities in children with autistic disorder,” J.
Pediatrics 135 no. 5 (1999) 559-563.
Wakefield
et al., Enterocolitis in children with developmental disorders. Am J
Gastroenterol. 2000 Sep;95(9):2285-95.
Ashwood P, Wakefield AJ. Immune activation of peripheral blood and mucosal CD3+ lymphocyte cytokine profiles in children with autism and gastrointestinal symptoms. J Neuroimmunol. 2006 Apr;173(1-2):126-34.
Ashwood
P, Anthony A, Torrente F, Wakefield AJ. Spontaneous mucosal lymphocyte
cytokine profiles in children with autism and gastrointestinal symptoms:
mucosal immune activation and reduced counter regulatory interleukin-10. J Clin
Immunol. 2004 Nov;24(6):664-73. Duodenal and
colonic mucosal CD3+ lymphocyte counts were elevated in ASD children compared
with noninflamed controls (p<0.03). In the duodenum, the proportion of
lamina propria (LP) and epithelial CD3(+)TNFalpha+ cells in ASD children was
significantly greater compared with noninflamed controls (p<0.002)
Ashwood
P, Anthony A, Pellicer AA, Torrente F, Walker-Smith JA, Wakefield AJ.
Intestinal lymphocyte populations in children with regressive autism: evidence
for extensive mucosal immunopathology. J Clin Immunol. 2003 Nov;23(6):504-17.
Torrente
F, Ashwood P, Day R, Machado N, Furlano RI, Anthony A, Davies SE, Wakefield AJ,
Thomson MA, Walker-Smith JA, Murch SH. Small intestinal enteropathy with
epithelial IgG and complement deposition in children with regressive autism.
Mol Psychiatry. 2002;7(4):375-82, 334.
Torrente
F, Anthony A, Heuschkel RB, Thomson MA, Ashwood P, Murch SH. Focal-enhanced
gastritis in regressive autism with features distinct from Crohn's and
Helicobacter pylori gastritis. Am J Gastroenterol. 2004 Apr;99(4):598-605. (Distinct patterns of gastritis
were seen in the disease states: diffuse, predominantly CD4+ infiltration in H.
pylori, and focal-enhanced gastritis in Crohn's disease and autism, the latter
distinguished by striking dominance of CD8+ cells, together with increased
intraepithelial lymphocytes in surface, foveolar and glandular epithelium.
Proliferation of foveolar epithelium was similarly increased in autism, Crohn's
disease and H. pylori compared to controls. A striking finding, seen only in
20/25 autistic children, was colocalized deposition of IgG and C1q on the
subepithelial basement membrane and the surface epithelium. The idea here was to look for a way at taking
a gastric biopsy for diagnosis rather than doing endoscopy)
Furlano
RI, Anthony A, Day R, Brown A, McGarvey L, Thomson MA, Davies SE, Berelowitz M,
Forbes A, Wakefield AJ, Walker-Smith JA, Murch SH. Colonic CD8 and gamma
delta T-cell infiltration with epithelial damage in children with autism. J
Pediatr. 2001 Mar;138(3):366-72
Wakefield AJ, Puleston JM, Montgomery SM, Anthony A, O'Leary JJ, Murch SH. Review article: the concept of entero-colonic encephalopathy, autism and opioid receptor ligands. Aliment Pharmacol Ther. 2002 Apr;16(4):663-74. Review.
Wakefield
AJ, Ashwood P, Limb K, Anthony A. The significance of ileo-colonic lymphoid
nodular hyperplasia in children with autistic spectrum disorder. Eur J
Gastroenterol Hepatol. 2005 Aug;17(8):827-36.
Wakefield
AJ, Murch SH, Anthony A, Linnell J, Casson DM, Malik M, Berelowitz M, Dhillon
AP, Thomson MA, Harvey P, Valentine A, Davies SE, WalkerSmith JA.
Ileal-lymphoid-nodular hyperplasia, non-specific colitis, and pervasive
developmental disorder in children. Lancet. 1998 Feb 28;351(9103):637-41. (the major article
that started off progressive research in the condition: showing that there was
potentially a gut inflammatory problem in autism)
Kokkonen
J, Ruuska T, Karttunen TJ, Mäki M. Lymphonodular hyperplasia of the
terminal ileum associated with colitis shows an increase gammadelta+ t-cell
density in children. Am J Gastroenterol. 2002 Mar;97(3):667-72.
Balzola
F, Barbon V, Repici A, Rizzetto M, Clauser D, Gandione M, Sapino A. Panenteric IBD-like disease in a
patient with regressive autism shown for the first time by the wireless capsule
enteroscopy: another piece in the jigsaw of this gut-brain syndrome?
Am J Gastroenterol
. 2005 Apr;100(4):979-81.Van
Heest R, Jones
S, Giacomantonio
M. Rectal
prolapse in autistic children
J Pediatr Surg. 2004 Apr;39(4):643-4 (This
is really very uncommon and they report 3 cases that required surgery. They say this is very odd for mentally
retarded groups.)
Krigsman A, Boris M, Goldblatt A. frequency of histologic enterocolitis and
lymphonodular hyperplasia in autistic children presenting for ileogolonoscopy
at IMFAR (May 7th 2004).
Intestinal obstruction in an autistic adolescent.
Serour F, Witzling M, Frenkel-Laufer D, Gorenstein A. Pediatr Emerg Care.
2008 Oct;24(10):688-90. They also
discuss the problems with the apparent gut obstruction that is reported by
parents in these patients.
Getting it wrong.
Autistic enterocolitis: fact or fiction? Galiatsatos P, Gologan A, Lamoureux E. Can J Gastroenterol.
2009 Feb;23(2):95-8. There have been
several reports of a link between autism and chronic gastrointestinal symptoms.
Endoscopy trials have demonstrated a higher prevalence of nonspecific colitis,
lymphoid hyperplasia and focally enhanced gastritis compared with controls.
Postulated mechanisms include aberrant immune responses to some dietary
proteins, abnormal intestinal permeability and unfavourable gut microflora. Two
autism spectrum disorder patients with chronic intestinal symptoms and abnormal
endoscopic findings are described, followed by a review of this controversial
topic
The early stool patterns of young children with autistic
spectrum disorder. Sandhu B, Steer C, Golding J, Emond A. Arch Dis Child. 2009 Jul;94(7):497-500. they tried to find if the stool pattern of
autistic children were similar to those of other enterocolitis (chronic)
children early in life. They found no
difference apart from a few periods.
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Currently (2008) I
could not find measurements of C-reactive protein, acute inflammatory protein
in serum, ESR etc simply looking for signs of the inflammation that may be
taking place. These are found in the
acute exacerbations of other IBDs, but during chronic changes the effect may
not be great.
Fernell E, Fagerberg UL, Hellström PM. No evidence for a clear link between active intestinal inflammation and autism based on analyses of faecal calprotectin and rectal nitric oxide. Acta Paediatr. 2007 Jul;96(7):1076-9. (this is unlike ulcerative colitis in which the protein, an inflammatory protein produced by the body is found in the stool. Also the lack of rectal nitric oxide disagrees. However, this is not all that damaging to the findings of histopathology in autism because of the amount of inflammation is much less and the samples could only be taken as faeces)
Intestinal cytokines in children with pervasive
developmental disorders. DeFelice ML, Ruchelli ED, Markowitz JE,
Strogatz M, Reddy KP, Kadivar K, Mulberg AE, Brown KA. Am J Gastroenterol.
2003 Aug;98(8):1777-82. We have
demonstrated no significant difference in production of IL-6, IL-8, and
IL-1beta between patients with pervasive developmental disorders and
age-matched controls. In general, intestinal levels of IL-6 and IL-8 were lower
in patients with pervasive developmental disorders than in age-matched
controls. These data fail to support an association between autism and GI
inflammation although the numbers were low and the identification of autistic
patients was also low.
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The most obvious
treatments might be the ones being used in other IBDs e.g. steroids, 5-ASA,
thalidomide, anti-immune drugs, specific
antibodies against cytokines. However
few have been tried. Also, changes in gut
flora might be of significant. See treatment.
Schneider CK, Melmed RD, Barstow LE, Enriquez FJ, Ranger-Moore J, Ostrem JA. Oral human immunoglobulin for children with autism and gastrointestinal dysfunction: a prospective, open-label study. J Autism Dev Disord. 2006 Nov;36(8):1053-64. (Following eight weeks of treatment, 50% of the subjects met prespecified criteria for response in GI signs and symptoms and showed significant behavioral improvement as assessed by the Autism Behavior Checklist and parent and physician rated Clinical Global Impression of Improvement.)
Welch MG, Welch-Horan TB, Anwar M, Anwar N, Ludwig RJ, Ruggiero DA. Brain effects of chronic IBD in areas abnormal in autism and treatment by single neuropeptides secretin and oxytocin J Mol Neurosci. 2005;25(3):259-74. (an attempt was may to use rat model inflammatory bowel disease – and the mental effects that they claim – and attempts to treat it using oxytocin and secretin, which are also found in the brain. They fully discuss the problems with the model and realise that work with clinical children would be of more value than the current model that they could put forward.
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The parents for a long time were quite aware of this but in text books from th 1980s and 1990s it was hardly mentioned. Several major assessments have been made of this but a good review has been by Valincenti. Argument as to the proportion of cases with GI symptoms has been great, probably simply because of the definition given to the parents of what the interviewer was looking for.
Valicenti-McDermott M, McVicar K, Rapin I, Wershil BK, Cohen H, Shinnar S. Frequency of gastrointestinal symptoms in children with autistic spectrum disorders and association with family history of autoimmune disease. J Dev Behav Pediatr. 2006 Apr;27(2 Suppl):S128-36. A history of GI symptoms was elicited in 70% of children with ASD compared with 28% of children with typical development. Abnormal stool pattern was more common in children with ASD (18%) than controls (typical development: 4%, p =.039; DD: 2%, p =.021). Food selectivity was also higher in children with ASD (60%) compared with those with typical development (22%, p =.001)
Molloy CA, Manning-Courtney P. Prevalence of chronic gastrointestinal
symptoms in children with autism and autistic spectrum disorders. Autism. 2003 Jun;7(2):165-71. (shows that 24 percent had a history
of at least one chronic gastrointestinal symptom. The most common symptom was
diarrhea, which occurred in 17 percent. There was no specific association
between chronic gastrointestinal symptoms and a history of developmental
regression. This figure has been argued
in that others have found that constipation was more prevalent than diarrhoea,
but they also found that this gut syndrome was different from the non-ASD
population i.e. it is a symtom of the ASD condition)
Afzal
N, Murch
S, Thirrupathy
K, Berger
L, Fagbemi
A, Heuschkel
R. Constipation
with acquired megarectum in children with autism Pediatrics. 2003 Oct;112(4):939-42. (they discuss the problem with constipation
being repeatedly reported in autistic children but to see a megarectum is
uncommon. The histopathology is looked
into but, being a single case it is difficult to interpret)
Sandhu B, Steer C, Golding J, Emond A. The early stool patterns of young children
with autistic spectrum disorder. Arch Dis
Child. 2009 Jul;94(7):497-500. Epub 2009 Mar 26 They
could find no specific signs of enterocolitis except for minor diarrhoea at
specific weeks of age in these children.
However it was done in retrospect, and was difficult to carry out. This was directly in disagreement with the
earlier work of other authors.
http://adc.bmj.com/cgi/content/abstract/94/7/497?maxtoshow=&HITS=10&hits=10&
Incidence of gastrointestinal symptoms in children with
autism: a population-based study. Ibrahim SH, Voigt RG, Katusic SK,
Weaver AL, Barbaresi WJ. Pediatrics. 2009 Aug;124(2):680-6. They found a specific increase in
constipation amongst the autistic group compared to controls (agreeing with
groups earlier apart from Sandu).
However, the ASD type or psychological form of the autism could not be
associated with the type of bowel form.
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