NPR: “Craptastic Voyage” and Fart Analysis

Surely a story for every gastroenterologist: “Before The Gas is Passed, Researchers Aim to Measure it in The Gut.”

An excerpt:

Kalantar-Zadeh and his colleagues propose in a paper in Trends in Biotechnologyonline Thursday two new devices that could keep a vigilant eye, or a nose in this case, on what’s going on deep in the gut….

The jar is pretty straightforward. A spoonful of poop goes in and a technician squeezes on a lid containing a sensor that detects the molecules of gas fuming inside and at what concentration…but he’s most excited about their other invention.

It’s a robotic pill that sniffs its way along a craptastic voyage through the gut. As the pill tumbles through, a membrane on the pill lets gasses pass onto a small molecular sensor inside that serves as its nose. The membrane blocks the other stuff sloshing around in the gut.

The pill notes the gasses that gut microbes produce, including oxygen, methane, hydrogen and hydrogen sulfide, which smells like rotten eggs. The pill’s sensor figures out how much of each gas is present, and beams the information out of the patient’s body through a tiny antenna…

The researchers aim to detect changes in gas content. As people’s health waxes or wanes because of stress or disease their intestinal ecosystems change too. Certain microbes may thrive in the new conditions while others struggle. As the populations shift, so will the concentrations of their distinctive gassy waste products.

My Take: This story reminds me about the joke I heard from a mentor about how can you tell if a person is an optimist.  An optimist is a person who finds a pile of manure under the tree on Christmas morning and declares: ‘Oh boy, I’m getting a pony.’

This story shows us that some researchers are true optimists as well; they see a lot of opportunity in studying stool and intestinal gases. Will this research will be useful or wind up being a pile of stool?

Also on NPR: Why Is Insulin So Expensive in the U.S. -summarizes recent commentary (N Engl J Med 2015; 372:1171-1175). This article is important for anyone concerned about escalating medicine costs.

Related blog post: “There is No ‘Healthy’ Microbiome” | gutsandgrowth

Emigration -One Way to Acquire Inflammatory Bowel Disease

A recent study (Shitrit AB, et al. Inflamm Bowel Ds 2015; 21: 631-35) highlights the phenomenon of acquiring inflammatory bowel disease (IBD) by moving from a non-developed country to a developed country; the implication is that the changes in environment and diet predispose towards the development of IBD.

This study examined Ethiopian Jews who migrated to Israel.  Using a case-control study, the authors compared 32 Ethiopian immigrants to 33 Ashkenazi patients with IBD.

Key findings:

  • No Ethiopian immigrants had a positive family history compared with 42% of Ashkenazi group.
  • Crohn’s disease was more prevalent in the Ethiopian immigrants: 94% versus 73%.
  • The Ethiopian immigrants lived in Israel for at least 8 years before developing IBD an da median duration of 13 years.

The study discusses the difficulty of diagnosing IBD in rural Africa but speculates that rather than an underdiagnosis of IBD, it is likely to have a true low prevalence of IBD.

Take-home message: It takes many years for the environment exposures to allow for the development of IBD.  Additional work is needed to establish the clinical, genetic, and microbial factors that influence the acquisition of IBD in immigrants to developing countries.  Understanding the susceptibility of immigrants would have widespread application.

Related blog posts:

More on Breastfeeding and Intelligence

A recent prospective study with 30 year followup indicates that breastfeeding is associated with improved IQ and income.

A summary of the study from NBC/Today Health.  An excerpt:

Babies who are breastfed for at least a year grow up to be significantly more intelligent as adults and they earn more money, too, a new study shows….

Many experts have questioned whether it’s breastfeeding that makes babies grow up healthier and smarter, or something else that their mothers do — maybe spending more time with them. In other studies done in the U.S. and Europe, mothers who breastfeed longer tend to be more educated and affluent — and that clearly has an effect on their kids.

This study was different.

“What is unique about this study is the fact that, in the population we studied, breastfeeding was not more common among highly educated, high-income women, but was evenly distributed by social class,” Horta said.

Coverage of story from NY Times with link to original study: an excerpt:

The study, in the April issue of Lancet Global Health, began in 1982 with 5,914 newborns. The duration of breast-feeding and the age when the babies began eating solid foods was recorded. Thirty years later, researchers were able to interview and test 3,493 of the original group….

Still, the authors acknowledge that this is an observational study, and that many other unmeasured factors could have influenced their results.

Related blog posts:

How Common are Clostridium difficile infections?

In 2011, Clostridium difficile was estimated, by a recent report from the CDC (NEJM 2015; 372: 825-34) to result in 453,000 infections in the U.S. based on surveillance data from 10 geographic regions.

Other key findings:

  • Approximately 29,000 deaths were attributed to Clostridium difficile infections
  • 65.8% of cases were health care associated.
  • 24.2% had onset in the hospital
  • Increased risk was particularly notable among the elderly, with an rate ratio of 8.65 in those 65 years of age or older
  • The aggressive NAP1 strain was evident in 30.7% of health-care associated infections compared with 18.8% of community-associated infections

Related posts:

Note to blog followers: Yesterday’s blog was retitled to “Radiologic Image for St. Patrick’s Day” rather than “Endoscopic Image for St. Patrick’s Day”

Withdrawing Therapy Leads To Relapse, Even if in Deep Remission

A recent study, presented as an oral abstract (thanks to Jeff Lewis for forwarding this reference), indicates that even in patients in deep remission, withdrawal of anti-TNF therapy leads to relapse in about 50% even when thiopurines are continued; this is in agreement with previous posts (see below).

Full abstract: OP007 Relapse after Deep Remission in Crohn’s disease. Here are the results and conclusion from the abstract:

Results

Sixty one patients were included and followed-up for a median of 28 months (range 7-47). After withdrawal of anti- TNFa therapy (44 infliximab and 17 adalimumab) 47 (77%) patients continued thiopurines. 32 (52.5%) patients relapsed until the end of follow-up with a median time to relapse of 8 months (range 1-25). The cumulative probability of maintaining remission was 82% at 6 months, 59% at 1 year and 51% at 2 years. Analysis of 28 patients who were in deep remission (endoscopic healing; faecal calprotectin <150mg/kg; CRP <5mg/l) revealed no better survival (82%, 64% and 40% at 6 months, 1 and 2 years, respectively). Four (8%) of relapsing CD patients required surgery 5 to 19 months after anti-TNFa cessation (2 for new stricture development, 1 for medically refractory flare and 1 for high grade dysplasia). In multivariate model only disease localization was risk factor of disease relapse (colonic vs. ileal/ileocolonic: OR 0.16, 95%CI: 0.03-0.72; p=0.02). Type of anti- TNFa preparation, smoking, disease behaviour, corticosteroid or thiopurine therapy, biological markers and anti-TNFa trough levels did not impact disease relapse.

Conclusion

Approximately half of CD patients relapsed within 2 years after anti- TNFa discontinuation despite being in endoscopic remission when anti-TNFa was stopped. The highest relapse rate was observed during the 1st year. Ileal disease increased the risk of disease flare, while no other risk factor was identified.

Related blog posts:

Bryce Canyon

Bryce Canyon

Breath Testing for Bacterial Overgrowth

A recent review (Clin Gastroenterol Hepatol 2014; 12: 1964-72) provides useful advice on testing for bacterial overgrowth and explains the limitations/obstacles in determining whether bacterial overgrowth is present.

Their recommendations:

  • Preparation: avoid antibiotics for 4 weeks prior to testing, avoid bismuth for 2-4 weeks, avoid probiotics for 2-3 weeks before testing, avoid consumption of non absorbable carbohydrates (eg. pasta, bread, fiber cereal, beans) the night prior
  • Glucose substrate for hydrogen breath testing is likely most suitable.  50 g in 250 mL.  Check baseline and then every 15 minutes over 120 minute testing interval.  Positive study: increase of 12 ppm (or more) over baseline and/or baseline >20 ppm (if proper test conditions)
  • Glucose breath test (GBT): sensitivity 20-93%, specificity 30-86%.  False-positive results can occur with rapid small-bowel transit.  GBT may not detect distal small bowel bacterial overgrowth.  Lactulose breath test (LBT) generally has lower specificity.
  • If breath testing is not available, small-bowel aspiration for quantitative culture is a reasonable consideration (challenging methodology).  Alternatively, a trial of empiric antibiotics may be considered if pretest probability is high.

Related blog post:

Two Shorts -Minimal Hepatic Encephalopathy and Fish Oil Protection

Briefly noted: JPGN 2014; 59: 689-94.  In this study, the authors took a consecutive sample of 13  children (ages 4-18 years) with non cirrhotic extrahepatic portal vein portal vein obstruction (EHPVO).  Three tests (fasting ammonia, quantified EEG, a psychometric battery) identified that minimal hepatic encephalopathy (MHE) affects approximately 50% of children with EHPVO.

Also: JPGN 2014; 59: 708-13.  In this study in 7-day old rabbits, those who receive TPN with fish oil-based lipid emulsion had protection against biochemical and liver histologic damage in comparison to rabbits who received TPN with soybean oil. Given the lack of head-to-head randomized studies in infants, this study provides some important evidence of fish oil benefit compared with standardized soybean lipid emulsion.

Related blog posts:

In NASH, is ALT Wrongly Used as a Marker of Liver Injury?

According to a recent report (Hepatology 2015; 61: 153-60), elevation of alanine aminotransferase (ALT) which is frequently used as an indicator to select patients for further investigations (eg. liver biopsy) is NOT a good indicator of liver parenchymal injury in patients with nonalcoholic fatty liver disease (NAFLD).

The researchers enrolled 440 patients and divided them into three groups: no NAFLD (n=60), NALFLD with normal ALT (n=165), and NAFLD with elevated ALT (n=215). The patients were overweight/obese patients prospectively recruited from newspaper ads, general medicine clinics and hepatology clinics at several VA hospitals. Those with history of alcohol abuse were excluded.

Numerous investigations were performed including liver fat by proton magnetic resonance spectroscopy (H-MRS), liver biopsy (n=293), and insulin resistance measurements.

Key findings:

  • NAFLD & NASH patients with elevated ALT had higher liver triglyceride content (P<0.0001), worse adipose tissue insulin resistance (ATIR) (P<0.0001), and lower plasma adiponectin (P<0.05).
  • Steatosis was worse on liver biopsy in those with NASH and elevated ALT (P<0.0001).
  • There were no differences in liver inflammation (P=0.62), ballooning (P=0.13), or fibrosis (P=0.12). Thus, patients with normal versus elevated ALT had similar severity of NASH liver histology.

Take-home message:  In adults, ALT values are “poor surrogate markers of disease activity” in NAFLD.  ALT values, in these patients, are indicative of metabolic disease.  Given the staggering numbers of individuals, adults and children, with fatty liver disease, the lack of simple screen tool is quite problematic.  Equally problematic is a lack of a simple treatment approach.

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Refractory Constipation -Terrific Update

Recently I attended a terrific talk by my partner, Jose Garza.  This lecture provided a great deal of information on refractory constipation for both pediatricians and pediatric gastroenterologists alike.

Elements of the talk included diagnosis, pathophysiology and differential diagnosis.

Rome III Criteria -Helpful in Diagnosis of Constipation

Rome III Criteria -Helpful in Diagnosis of Constipation

JG1 pathophys

Is it Hirschsprung's Disease?

Is it Hirschsprung’s Disease?

Some of the more useful points.

  1. AXR should not be used to make diagnosis of constipation.
  2. Many refractory constipation patients are stooling fine and actually labeled as constipation instead of a functional abdominal pain disorder.  That is, they are complaining of stomach pain and have been erroneously told they are constipated (see point #1).
  3. Miralax remains a 1st line agent for constipation. In individuals with fecal soiling, if miralax is not working and they have had appropriate cleanout, then senna laxative may be helpful.
  4. Sitz markers are particularly helpful in proving stooling when teenager claims to not be stooling for a month and in proving functional fecal retention rather than nonretentive soiling.
  5. If good treatment is not working, then refer to neurogastroenterology.

Related blog posts:

JG3 -Help