Tag Archives: microbiome

Colic Microbiome

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A new study identifies a potential microbiome signature that is associated with colic (Pediatrics 2013; 131: e550-58). Thanks to Mike Hart for this reference.

With new technology, the microbiome’s role in many gastrointestinal conditions is being unraveled.  For colic, there has been concern about that an abnormal microbiome has been contributing to the pathophysiology.  On a personal level, I have had an interest in this subject for quite a while:

In this current study, the authors serially followed the microbiome infants in a prospective longitudinal project.  Nine stool specimens were obtained from each infant. Four were obtained in the first month at day of life 2, 7, 14, and 28 days.  Five were obtained at 3 to 5 months.  All specimens were stored at -20°C until analyzed by the “Human Intestinal Tract Chip (HITChip).” The HITChip microarray was considered satisfactory if 2 independent hybridizations had >95% correlation.  These microarrays “showed a dynamic range of >10,000-fold and >200 independent microarray readouts were used.”

Of 160 healthy term infants, the authors identified colic in 25% who averaged >180 minutes of crying per day over a four-day period.  Then, the authors selected the 12 infants who cried the most and compared them to the 12 infants who cried the least.

Results:

  • In the infants who were highly similar, the “infants with colic showed a significantly reduced microbiota diversity at 14 and 28 days of life.”  Proteobacteria, including Enterobacter aerogenes, Escherichia coli, and Klebsiella pneumoniae, were increased with more than a doubled abundance.  Bifidobacteria and lactobacilli were decreased in colicy infants.
  • At about 3-4 months of age, the colic group had a similar microbiome as the non-colicy group.
  • The authors speculate that proteobacteria might cause inflammation and may displace helpful bacteria.  Certain butyrate-producing bacteria like Butyrivibrio crossotus and Coprococcus estates were more commonly present in the non-colicy group.  The authors note that butyrate reduces the pain sensation in adults.

Bottom-line:

These results could explain why administration of probiotics (and possibly antibiotics) can result in a decrease in colic symptoms.

Related blog entries:

Additional references:

  • -Pediatrics 2010; 126: e526.  Double-blind randomized placebo-controlled trial of Lactobacillus reuteri.
  • -J Pediatr 2009; 155:823. Increased calprotectin in colicy infants. n=36. editorial pg 772.
  • -J Pediatr 2009; 154: 514-20. Colic and reflux. (Orenstein et al), & 475 (editorial -Putnam). PPIs (lansoprazole) do not help colicy Sx in infants c GERD. n=162. Increased resp infections in pts on PPIs. 44% response in Rx & control group.
  • -J Pediatr 2008; 152: 801. Probiotic helped reduce colic sx in 30 preterm infants, Lactobacillus reuteri
  • -Pediatrics 2007; 119; e124. Probiotics reduced colic in breastfed babies more than simethicone. n=83, lactobacillus reuteri, 10-8th power per day. Decreased crying 18 minutes per day at 1 week compared to simethicone & by 94 minutes/day at 4 weeks (95% response vs 7% of simethicone)
  • -Pediatrics 2005; 116: e709. Low-allergen maternal diet was helpful.
  • -Arch Pediatr Adol Med 2002; 1183 &1172. lack of sequelae on maternal mental health.
  • -Arch Pediatr Adol Med 2002; 156: 1123-1128. colic 24% of infants, breastfeeding did not help.
  • -Pediatrics 2002; 109: 797-805. carbohydrate malabsorption with breath testing in colicy infants, n=30. 2 hour fasting period.
  • -Arch Dis Child 2001; 84: 138-41. Lack of benefit (vs placebo) of chiropractic manipulation for colic, n=100. 86 completed study. 70% improved vs 60% in placebo.
  • -JPGN 2001; 33:110-111. Lack of assoc c GER
  • -Pediatrics 2000; 106: 1349. Use of hydrolysate decreased crying by 63mins/day
  • -Pediatrics 2001; 108; 878-882. No assoc between colic and markers of atopy/asthma/allergy.

Microbiome in pediatric ulcerative colitis

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Alterations in the gastrointestinal tract microbiome may play an important role in many digestive conditions.  A recent article examines microbiome alterations in children with severe ulcerative colitis (UC) (Inflamm Bowel Dis 2012; 18: 1799-1808).

Stool samples from 26 healthy children and 27 children with severe UC were prospectively studied.  After DNA extraction, PCR amplification and microarray hybirdization were performed and analyzed.   None of the patients in the study had received antibiotics or probiotics in the preceding month.

Key findings:

  • There were substantial reductions in “richness,” diversity, and evenness of the gut microbiome in UC patients.  (Richness is a term used to reflect the number of detected phylospecies.)
  • There was a decrease in signal in almost all  phylospecies.
  • The number of phylospecies was reduced in UC (266 ± 69) vs controls (758 ± 3)
  • Steroid responders had even fewer phylospecies compared with responders (142 ± 49  vs. 338 ± 62)

It is not surprising that the stools from these children are much different.  The issues of causation and whether a snapshot of the microbiome diversity will have clinical relevance is not clear.  It is possible that antimicrobials may make an individual more susceptible to inflammatory bowel disease by altering the individual’s microbiome.

Related blog entries:

Eat your veggies…if you don’t want to get sick | gutsandgrowth

Why are we seeing so many more cases | gutsandgrowth

Eat your veggies…if you don’t want to get sick

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Maybe your mother was right –you should eat your vegetables!   For a long time, it has been known that dietary changes can be used to treat Crohn’s disease.  The specifics about what type of diet and the reasons for how diet promotes a healthy gastrointestinal tract are being unraveled.  A person’s diet affects their microbiome; and, a number of recent articles have highlighted the microbiome in both functional and nonfunctional disorders (see below).

An even more fascinating article is in last week’s New England Journal of Medicine (NEJM 2012; 366: 181).  This article discusses two publications which show how certain dietary components interact with intestinal immune receptors.

  • Kiss EA et al. Science 2011 October 27 (Epub ahead of print).
  • Li Y et al. Cell 2011; 147: 629-40.

This NEJM article implicates a typical ‘Western’ diet as a contributor to inflammatory bowel disease (IBD).  However, a diet high in vegetables may prevent or reduce inflammation.  One mechanism whereby vegetables affect the GI tract is through the AhR (aryl hydrocarbon) receptor.  Some vegetables, like broccoli, cabbage, and brussel sprouts, are natural ligands for this receptor.  A mouse model has shown that AhR deficiency “results in increased epithelial vulnerability, immune activation, and altered composition of the microbiota.”  In addition, AhR is down-regulated in the intestinal tissue of persons with IBD.  AhR ligands are associated with increased interleukin-22 which promotes intestinal integrity.

Additional work regarding the optimal diet are ongoing.  There has been an interest in a ‘carbohydrate specific diet.’  This year’s NASPGHAN meeting (abstract #48)  presented data on this diet from a retrospective study.  This poster described five patients on monotherapy (diet alone) and at 6 months –good results in four patients (80%).  A few prospective studies are underway; in fact, a prospective study with patients from our office will be presented at this year’s DDW.  Initial results look promising (personal communication from lead investigator, Stan Cohen).

Additional references:

  • -Gastroenterology 2010; 139: 1816, 1844.  Microbiome & affect on IBD vs mucosal homeostasis.
  • -J Pediatr 2010; 157: 240.  Microbiota in pediatric IBD -increased E coli and decreased F praunsitzil in IBD pts.
  • -Gastro 2011; 141: 28, 208.  GM-CSF receptor (CD116) defective expression & function in 85% of IBD pts. n=52.
  • -Scand J Gastro 2001; 36: 383-8.  Elemental & polymeric diets successful in maintaining remission in ~43% of adults with complete steroid withdrawal.
  • -Clin Gastro & Hepatology 2006; 4: 744.  10 weeks of exclusive modulen (along with clears) had 79% response rate (n=37).  Better histologic response than steroids.
  • -J Pediatr 2000; 136: 285. Nutritional treatment w polymeric diet is effective w/in 8 weeks in 32/37.
  • -JPGN 2000; 31: 3 & 8.  EN about as effective as steroids for primary Rx.
  • -Can J Gastroenterol 1998; 12(8):544-49. Patients, diets and preferences in
    a pediatric population with Crohn’s disease.
  • -Gastroenterology 1988; 94:603-610. Chronic intermittent elemental diet improves growth failure in  children with Crohn’s disease.
  • -JPGN 1989; 8:8-12. Nutritional support for pediatric patients with inflammatory bowel disease.
  • -J Pediatr 2000; 136: 285-91. The role of nutrition in treating pediatric Crohn’s disease in the new millennium.