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About gutsandgrowth

I am a pediatric gastroenterologist at GI Care for Kids (previously called CCDHC) in Atlanta, Georgia. The goal of my blog is to share some of my reading in my field more broadly. In addition, I wanted to provide my voice to a wide range of topics that often have inaccurate or incomplete information. Before starting this blog in 2011, I would tear out articles from journals and/or keep notes in a palm pilot. This blog helps provide an updated source of information that is easy to access and search, along with links to useful multimedia sources. I was born and raised in Chattanooga. After graduating from the University of Virginia, I attended Baylor College of Medicine. I completed residency and fellowship training at the University of Cincinnati at the Children’s Hospital Medical Center. I received funding from the National Institutes of Health for molecular biology research of the gastrointestinal tract. During my fellowship, I had the opportunity to work with some of the most amazing pediatric gastroenterologists and mentors. Some of these individuals included Mitchell Cohen, William Balistreri, James Heubi, Jorge Bezerra, Colin Rudolph, John Bucuvalas, and Michael Farrell. I am grateful for their teaching and their friendship. During my training with their help, I received a nationwide award for the best research by a GI fellow. I have authored numerous publications/presentations including original research, case reports, review articles, and textbook chapters on various pediatric gastrointestinal problems. In addition, I have been recognized by Atlanta Magazine as a "Top Doctor" in my field multiple times. Currently, I am the vice chair of the section of nutrition for the Georgia Chapter of the American Academy of Pediatrics. In addition, I am an adjunct Associate Clinical Professor of Pediatrics at Emory University School of Medicine. Other society memberships have included the North American Society for Pediatric Gastroenterology Hepatology and Nutrition (NASPGHAN), American Academy of Pediatrics, the Food Allergy Network, the American Gastroenterology Association, the American Association for the Study of Liver Diseases, and the Crohn’s and Colitis Foundation. As part of a national pediatric GI organization called NASPGHAN (and its affiliated website GIKids), I have helped develop educational materials on a wide-range of gastrointestinal and liver diseases which are used across the country. Also, I have been an invited speaker for national campaigns to improve the evaluation and treatment of gastroesophageal reflux disease, celiac disease, eosinophilic esophagitis, hepatitis C, and inflammatory bowel disease (IBD). Some information on these topics has been posted at my work website, www.gicareforkids.com, which has links to multiple other useful resources. I am fortunate to work at GI Care For Kids. Our group has 17 terrific physicians with a wide range of subspecialization, including liver diseases, feeding disorders, eosinophilic diseases, inflammatory bowel disease, cystic fibrosis, DiGeorge/22q, celiac disease, and motility disorders. Many of our physicians are recognized nationally for their achievements. Our group of physicians have worked closely together for many years. None of the physicians in our group have ever left to join other groups. I have also worked with the same nurse (Bernadette) since I moved to Atlanta in 1997. For many families, more practical matters about our office include the following: – 14 office/satellite locations – physicians who speak Spanish – cutting edge research – on-site nutritionists – on-site psychology support for abdominal pain and feeding disorders – participation in ImproveCareNow to better the outcomes for children with inflammatory bowel disease – office endoscopy suite (lower costs and easier scheduling) – office infusion center (lower costs and easier for families) – easy access to nursing advice (each physician has at least one nurse) I am married and have two sons (both adults). I like to read, walk/hike, bike, swim, and play tennis with my free time. I do not have any financial relationships with pharmaceutical companies or other financial relationships to disclose. I have helped enroll patients in industry-sponsored research studies.

“Mutant Ninja Viruses”

Yesterday’s post “Understanding HCV Treatment Failures with Sofusbuvir” provided a summary of why patients with hepatitis C virus (HCV) genotype 3 may not respond to therapy. Now a terrific article (Hepatology 2015; 61: 471-80, editorial, titled “Mutant Ninja Viruses” 421-23) looks at why some patients with the favorable HCV genotype 2 may fail to respond.

By using extensive genotyping data and sequencing, the authors were able to determine why some patients with genotype 2 did not respond to combination therapy with ribavirin/sofusbuvir.  These patients were characterized by as genotype 2 based on Siemens VERSANT HCV Genotype INNO-LiPA 2.0 Assay.  This assay “looks at conserved sequences in the 5′ region of the virus.” However, these patients were genotyped as well using a technique to examine the 3′ region of the virus.  From among more than 2000 samples, the two assays gave divergent results in 0.5% of the cases with the 5′ end indicating genotype 2 and the 3′ end indicating genotype 1.

What is happening?

  • Detailed analyses of these discordant viruses showed that they were hybrid viruses with a crossover point located in the NS2/NS3 region.
  • In patients with these hybrid viruses, only 3 of 11 responded to therapy, indicating that they behave like genotype 1 patients.

Bottomline: “These novel viruses are true viral Ninjas hiding a challenging array of ‘difficult-to-cure’ genotype 1 enzymes under an ‘easy-to-cure’ genotype 2 coat.

Understanding HCV Treatment Failures with Sofusbuvir

While the new treatments for hepatitis C have improved dramatically in terms of cure rates and side effects (and pharmaceutical companies bottom-line), there are still patients who do not respond, especially those with genotype 3.  A recent study (Hepatology 2015; 61: 56-65) has provided some information into why this is happening.

A division of the FDA looked into five sofosbuvir (SOF) trials and performed sequencing to characterize potential resistance-associated substitutions.

Key findings:

  • Nonstructural protein 5B (NS5B) substitutions, L159F and V321A, emerged in 2.2%-4.4% of subjects who failed SOF treatment.
  • Baseline substitutions in 316 were associated with a reduced response in HCV genotype 1b subjects.
  • This study identified only 11 patients with genotype 3 with potentially relevant substitutions.

Bottomline: In the vast majority of patients, no resistance-associated substitution could be identified, indicating that we have a lot to learn why some patients are not responding.

Related blog posts:

Theses Eggs Contain Eggs!

Theses Eggs Contain Eggs!  Is the “allergen information” really necessary in this case?

An Oral Oligonucleotide in the Crohn’s Treatment Pipeline & Smart Patients

The preliminary data are in from a phase II study regarding Mongerson, a oral pill for Crohn’s disease.

Here’s the link: Oral oligonucledotide shows efficacy, safety in Crohn’s

Here’s an excerpt from GI & Hepatology News:

Fourteen days of daily treatment with mongersen, an oral, antisense oligonucleotide, safely produced remissions in two-thirds of patients with Crohn’s disease in a phase II study with a total of 163 patients…

Mongensen “is not an anti-inflammatory drug. It removes a brake on the normal immunosupressant mechanism in the gut, and that is why the effect is long lasting. It allows TGF [transforming growth factor]-beta to work again [as an endogenous immunosuppressant] and promote healing,” said Dr. Monteleone, a professor of gastroenterology at the University of Rome Tor Vergata.

Oligonucleotide blockade of the production of the Smad7 intracellular protein prevented the inhibitory effect of Smad7 on TGF-beta and thus allowed TGF-beta to inhibit cytokine production and T lymphocyte signaling (J. Clin. Invest. 2001;108:601-9).

From ImproveCareNow — Smart Patients Online Community -may be helpful resource for families:

There are many social networks and online communities for IBD, but we have chosen to partner with the Smart Patients team because their custom-built, disease-specific forums offer a truly safe, warm and engaging experience for users. Smart Patients also offers conversation tagging, and clearly defined community norms, which means community members are highly likely to find the answers they need and highly unlikely to be trolled. And because the conversations are arranged using tags and completely searchable, you can always find what you’re looking for.

The Smart Patients team and ImproveCareNow have partnered to create an online IBD community that is supportive and also powerful. The Smart Patients IBDcommunity has the power to improve health and health care systems through patient and family peer-to-peer learning.

 

Updated Guidelines on Genetic Testing/Management for Hereditary GI Cancer Syndromes

Here’s a link to abstract: Updated Guidelines on Genetic Testing/Management for Hereditary GI Cancer Syndromes (The American Journal of Gastroenterology 110, 223-262 (February 2015) | doi:10.1038/ajg.2014.435).  This ACG guideline specifically discusses genetic testing and management of Lynch syndrome, familial adenomatous polyposis (FAP), attenuated familial adenomatous polyposis (AFAP), MUTYH-associated polyposis (MAP), Peutz–Jeghers syndrome, juvenile polyposis syndrome, Cowden syndrome, serrated (hyperplastic) polyposis syndrome, hereditary pancreatic cancer, and hereditary gastric cancer.

I glanced at the guideline –it is about 40 pages in length.  It provides a lot of in-depth information on these infrequent disorders.

Some online resources for similar information:

Family Meals –Protection Against Obesity?

According to a 10-year longitudinal study, increased family meal frequency during adolescence was associated with a reduced odds of overweight or obesity (Berge JM et al, J Pediatr 2015; 166: 296-301, editorial 220-21).

The data from this study derived from Project EAT I and EAT III which examined at baseline middle school and high school students at 31 public schools in Minnesota.  Ultimately the participants (n=2117) were followed over 10 years.

Key finding:

  • “Results showed that eating family meals together, ranging from 1-2 to 5 or more times during 1 week, was significantly predictive of lower odds of being overweight or obese 10 years later.”  This effect was largest among African American participants.
  • Odds ratios for overweight/obesity was similar with any frequency of family meals compared to no family meals: 1-2 times/week OR 0.67, 3-4 times/week OR 0.50, and 5 or more/week OR 0.68

Why does this occur?

There is not an answer to this question.

Speculation from the authors:

  • “Healthier meals”
  • “Opportunities for emotional connection”
  • “Parental modeling”

In my view, family meals may be an epiphenomenon.  It may be a marker for a more organized household which is likely to have some favorable effects.

Bottomline: Another reason to eat together.  Besides having a chance to catch up on your kids, it may keep them healthier.

Related blog posts:

When A Disease Turns Out to Be Fictitious -The Sad Story on Sphincter of Oddi Dysfxn

When parents make up diseases in their children, the consequences can be dire.  What happens when doctors find out that a disease that they have been treating probably doesn’t exist?

  • Cotton PD et al. “Effect of endoscopic sphincterotomy for suspected sphincter of Oddi dysfunction on pain-related disability following cholecystectomy: the EPISOD randomized clinical trial” JAMA 2014; 311: 2101-2109.

A detailed analysis of this study (Gastroenterol 2015; 148: 440-44) and the author’s reply provides some insight into that questions and helps place this study and its results into context.

Key points from the Gastroenterology Selected Summary:

Background:

  • “Sphincter of Oddi dysfunction (SOD) is the term used to describe an episodic abdominal pain syndrome, typically occurring in young to middle-aged women in the setting of prior cholecystectomy…SOD remains a diagnosis of exclusion.”

Design:

  • “The investigators conducted a double-blind, sham-controlled, randomized trial at 7 US tertiary centers, enrolling 214 adult post-cholecystectomy patients with debilitating abdominal pain due to suspected biliary SOD (predominantly type III).” Sham patients underwent ERCP, manometry, and pancreatic duct stenting.
  • Patients were randomized 2:1 to sphincterotomy or sham; those randomized to sphincterotomy and subsequently shown to have a hypertensive pancreatic sphincter were then re-randomized (1:1) to have biliary or combined biliary/pancreatic sphincterotomies.

Results:

  • “Most patients in both study groups experienced considerable reduction in their pain disability scores…the proportion meeting the trial’s 1-year primary endpoint was higher among those treated with sham compared with sphincter ablation (37% vs. 23%, P=.01)”
  • “The manometry findings did not predict treatment success.”  There were no other useful predictors of success identified (eg. elevated liver enzymes, prior stone at cholecystectomy)
  • Adverse effects from procedures included 26 cases of acute pancreatitis (2 severe) and 2 perforations.

Discussion:

  • “The results of this trial are fascinating…the authors, many of whom had dedicated entire careers to the management of these patients using the very procedure they have now conclusively shown to be futile, may be understandably disheartened by the results.”
  • Numerous limitations of the study are noted.  In particular, “the 1-year time frame of the trial is likely to have been too short to capture the deleterious impact of prophylactic pancreatic duct stenting, which…has been associated with interval induction of pancreatic ductal abnormalities mimicking chronic pancreatitis.”
  • It is our view that the authors’ data…provide an unambiguous mandate for imposing an immediate moratorium on subjecting this group of patients to ERCP.

Dr. Cotton’s reply:

  • “It may be premature to discard the whole concept of sphincter dysfunction as a cause of pain.”
  • He indicates that “gallbladder dyskinesia” is another related question and was the reason for surgery in half of EPISOD subjects.
  • The results of the study “clearly show the need for equally stringent studies to answer the many remaining questions.”

For those who read this much of this post:  I wanted to let you know that yesterday’s online post on early peanut introduction was updated with recommendations from the associated editorial.

Related blog posts:

Another headline from Freaknomics Website follows. Of course I probably should think twice about poking fun at typos given the volume of them on this blog.

Screen Shot 2015-02-22 at 9.33.13 AM

The Peanut Story -From NEJM Blog

If you listen to any news source over the last day, there is a buzz about a new study regarding early peanut exposure in the prevention of peanut allergy.  A link to a blog that summarizes the study and the associated editorial:  NEJM Blog -Peanut Consumption in Infants For those who prefer a 1 minute video summary: Here’s a brief excerpt: The Learning Early About Peanut Allergy (LEAP) study, now published in NEJM, was a randomized, open-label, single-center study designed to compare two strategies to prevent peanut allergy: consumption or avoidance of peanuts. The trial enrolled children 4-11 months of age who were thought to be at high risk for developing a peanut allergy based on a history of severe eczema or egg allergy.  Participants were given a skin prick test to evaluate for sensitivity to peanut.  Children with a negative skin prick result (meaning no measureable skin wheal) or moderately positive (1-4mm wheal) were included in the study; children with a highly positive result (wheal >4mm) were excluded.  Infants were then stratified based on their skin prick test results. 530 infants in the skin prick test negative group and 98 infants in the skin prick test positive group were randomly assigned to either consume 6g of peanut protein per week or to avoid peanuts.  The primary outcome was the proportion of participants with a peanut allergy at age 5, determined by response to an oral peanut protein challenge. The results were impressive:  in the negative skin prick test group, the prevalence of peanut allergy at age 5 was 13.7% in the avoidance group versus 1.9% in the consumption group (P<0.001).  In the positive skin prick test group, 35.3% of those who avoided peanuts were allergic as compared with 10.6% of the consumption group (P=0.004).

This study (NEJM 2015; 372: 803-13) showed that the early introduction of peanuts (median age 7.8 months) significantly decreased the frequency of the development of peanut allergy among children at high risk for this allergy.  These results will result in changes in practice recommendations.  It is noted that approximately 10% of children who had a wheal of more than 4 mm develop after skin-prick testing were excluded.  The associated editorial (pages 875-77) by Rebecca Gruchalla and Hugh Sampson recommends a cautious approach: “any infant between 4 months and 8 months of age believed to be at risk for peanut allergy should undergo skin-prick testing for peanut. If the results are negative, the child should be started on a diet that includes 2 g of peanut protein three times a week for at least three years.” For those with mild positivity, “the child should undergo a food challenge…by a physician who has experience performing a food challenge.”

Marketing to Doctors -Informative Satire

One of my colleagues recently shared a youtube link that I recommend highly to anyone who is concerned about the relationship between pharmaceutical companies and physicians.  As with any good piece of satire, it is both funny and thought-provoking.  As one would question the impartiality of politicians who receive funds from constituents with a specific agenda, likewise patients may question whether physicians are unduly influenced by their relationship with pharmaceutical companies.

For those too busy to enjoy the entire ~17 minutes, watch the last three minutes:

 

Taking One ‘Bite’ At A Time -For Celiac Diagnosis

A small study (reference from KT Park’s Twitter feed –Gastrointestinal Endoscopy DOI: http://dx.doi.org/10.1016/j.gie.2014.10.024) suggests that taking a single biopsy per pass rather than two biopsies per pass results in better quality specimens:

Link: Endoscopic Biopsy Technique in the Diagnosis of Celiac Disease

Here are the results and conclusion of the abstract:

Results

Patients (N = 86) were enrolled, 47% with known celiac disease, 36% with suspected celiac disease, and 17% with an unknown celiac disease status. Well-oriented biopsy specimens were noted in 66% of patients with the single-biopsy technique and 42% of patients with the double-biopsy technique (P < .01). Analysis of matched pairs showed improved orientation with the single-biopsy technique (odds ratio 3.1; 95% confidence interval, 1.5-7.1; P < .01). This persisted in subgroup analysis of patients with known celiac disease (P = .02), villous atrophy (P = .02), and a final diagnosis of celiac disease (P < .01).

Conclusion

The single-biopsy technique improves the yield of well-oriented duodenal biopsy specimens. Endoscopists should consider taking only 1 biopsy specimen per pass of the forceps in patients undergoing biopsies of the duodenal mucosa.

Related blog posts:

I'm the one on the right

I’m the one on the right