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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.

Thiopurines associated with reduced risk of colon cancer

A recent study provides some good news for those using thiopurines (6-mercaptopurine and azathioprine) (Gastroenterol 2013; 145: 166-75).

Using the observational cohort enrolled in the French CESAME study (Cancers et Surrisque Associe aux Maladies Inflammatoires Intestinales En France), the authors followed 19,486 patients with IBD.  60.3% had Crohn’s disease, and 30.1% were receiving thiopurine therapy.  The study period was 2004-2007.  At the start of the study, 2841 patients (14.6%) had long-standing extensive colitis.

Among patients with long-standing extensive colitis, the hazard ratio for colrectal high grade dysplasia and cancer was 0.28 for those who received thiopurine therapy compared with those who never received thiopurine therapy.

Thus, this prospective study showed that while colorectal cancer (CRC) was increased in IBD patients with long-standing colitis, this risk was less among the subset who were treated with thiopurines.  Some previous studies have not found a reduction in CRC risk, though they may have been underpowered and biased as these studies came from referral centers.

The authors also cautioned that more than 1/3rd of CRC cases occurred in those without extensive colitis which may necessitate a lower threshold for screening colonoscopy.

Related blog posts:

Magnets: Clear and Present Danger

As noted in previous blogs (see below for links), ingested magnets represent a significant problem.  Two more studies add data to this issue:

  • JPGN 2013; 57: 14-17.
  • JPGN 2013; 57: 18-22.

The first study relates a retrospective single-hospital experience from 1995-2012 (from Boston).  In total, 112 cases of magnet injuries were identified using an initial computer search followed by manual chart review.  The mean patient age was 6 years.  The incidence rate ratio of 3.44 during the period 2007-2012 indicates a significant uptick in these injuries compared with the prior period. In addition, “office toys” accounted for 18 of 45 injuries during this latter period. Nature of injuries: swallowed magnets accounted for 86% of these injuries with 13 (12%) requiring endoscopic removal and 4 (4%) needing surgical intervention.

The second study analyzed a nationally representative same from the US Consumer Product Safety Commision Database (NEISS) for emergency department (ED) visits involving magnet ingestion in children (< 18 years) from 2002-2011.  NEISS sample includes >100 hospitals and 7 children’s hospitals.  The authors note that searching NEISS is not always straight-forward as specific product codes need to be entered like toy, kitchen gadget, and others.  The findings:

  • 16,386 suspected magnet ingestion related ED visits from 2002-2011
  • 59.4% were boys , 54.7% were younger than 5 years
  • There was a >8-fold increase in visits for these ingestions from 2002 to 2011.
  • Study limitations: NEISS database –likely underestimates problem, and no specific NEISS code for magnets

The authors note that one institution has started screening for magnets prior to MRI after a 5 year-old with unrecognized magnet ingestion developed intestinal perforations after undergoing an MRI for torticollis.

Take-home message: Magnets are, in the words of Tom Clancy, a ‘Clear and Present Danger’ as ingestion of more than one magnet creates a high risk of perforation or fistula.

Related blog posts:

 

 

 

Emerging Targets for Hepatitis C -Part 2

The best review on new therapies for HCV that I’ve read in quite a long time:

Hepatology 2013; 58: 428-38

First the abbreviations:

  • ASV -Asunaprevir
  • BOC -boceprevir
  • DAA -direct-acting antiviral
  • DCV -daclatasvir
  • DNV -danoprevir
  • NI -nucleos(t)ide inhibitor
  • NNI -nonnucleos(t)ide inhibitor
  • SIL -silibinin
  • SOF -sofosbuvir
  • TVR -telaprevir

More terminology:

  • First-generation NS3/4A protease inhibitors (TVR, BOC) are “defined as agents that display potent activity on HCV-1 but oppose a low barrier to selection of resistant viral variants and are not effective on all viral genotypes.”
  • Second generation NS3/4A protease inhibitors are “defined as agents that pose a high barrier to the development of viral resistance, retain activity against the viral variants that are resistant to first-generation compounds, and are active across all HCV genotypes.”
  • First-wave therapies are covalent linear inhibitors and second-wave therapies are either non covalent linear or macrocyclic inhibitors.

What are the weapons?

Some second-wave, first generation NS3/4A PIs: faldaprevir, asunaprevir, sovaprevir, simeprevir, danoprevir, and vaniprevir.  These agents have similar clinical efficacy as BOC and TVR but are easier to administer, usually once-a-day.  Some of these agents have better activity  against several genotypes.

MK-5172, 2nd-generation NS3/4A PI,  has pan-genotype activity & maintains antiviral activity against most mutations that confer resistance to 1st-generation PIs.

DCV, a NS5A inhibitor, has potent HCV activity but a low barrier for viral resistance; thus, it is likely to be used in combination with other agents.  Multiple NS5A inhibitors are in development.

SOF, a NS5B polymerase inhibitor, is being studied in interferon-free combinations.  Viral resistance has been rare in clinical studies with this agent.  Multiple other agents in this class are in study.

NS5B polymerase inhibitor NNIs bind to less conserved sites on HCV; thus, initial results have not been as promising.  Several NNIs, including setrobuvir and lomibuvir (& others), are being tested in combination in all-oral, interferon-free regimens.

SIL, a NS4B binding inhibitor, is an intravenous agent that has shown some efficacy in liver transplant patients.  Other oral agents, like clemizole, are being investigated.

How these agents may be useful:

  1. “The first step forward in anti-HCV therapy will be the introduction of a second-wave PI to used in combination with PEG-IFN/RBV.” Simeprevir, faldaprevir, and ritonavir-boosted danoprevir (DNV) will be easier to administer than TVR or BOC as they can be given once-daily.  In addition, these drugs are more active against genotypes 2, 4, 5, and 6.  In fact, ritonavir-boosted DNV in combination with PEG-IFN/RBV had 100% SVR efficacy for patients with HCV-4 in one trial.
  2. Next, will be NS5A and NS5B inhibitors to be used in combination with previous agents.  These agents will compete with second-wave PIs but “whether they will provide a true innovation in terms of viral cure rates, safety profile, or patient tolerability is still to be demonstrated.”  These agents work better with other DAAs.
  3. Finally, all-oral combinations will enter the market.  “The first all-oral anti-HCV regimen will be likely available in 2014 for HCV-2 and HCV-3 patients.”  SOF with RBV has had good success rates in previous studies.

Potential Problems:

  • Many of these investigational agents have been studied in easy-to-cure populations.
  • Lack of data in advanced fibrosis/cirrhosis.
  • Safety questions in post-transplant populations.
  • Affordability.  “It is possible that these innovative regimens will be confined to groups of patients in whom TVR/BOC or PEG-IFN/RBV are either ineffective or unsafe.”  Some patients may receive ‘maginally less effective and less tolerable drugs for cost-containing issues.’
  • Drug resistance.  This is likely to become a clinical problem with all oral IFN-free regimens. with TVR/BOC, resistance has limited significance due to HCV quasispecies reverting back to wild-type virus after stopping TVR or BOC.  It is unclear if this will be the case with other DAAs.

 

 

Emerging Targets for Hepatitis C -Part 1

The latest advances in hepatitis C are related in several recent publications:

  1. Hepatology 2013; 57: 2143-54.
  2. Hepatology 2013; 57: 2155-63.
  3. Clin Gastroenterol Hepatol 2013; 11: 612-619.

The first two studies provide specific information about the effectiveness of Faldaprevir combined with peginterferon alfa-2a/ribavirin (PEG/RBV) in treatment-naive patients and patients with prior nonresponse respectively.  The third reference provides the big picture regarding all of the emerging treatments.

In the first study, the “SILEN-C1” phase 2 trial, 429 patients without cirrhosis were randomized to several treatment arms.  423 of the 429 patients were genotype 1.  This large study involved 89 centers in 15 countries.  All of the treatment groups received PEG/RBV along with either placebo, faldaprevir 120 mg with lead-in (LI), faldaprevir 240 mg LI and faldaprevir 240 mg without LI.   Faldaprevir is a NS3/4A protease inhibitor which can be administered orally once a day.  Results: SVR achieved in 56% (placebo), 72% (faldaprevir 120mg LI), 72% (faldaprevir 240 mg LI), and 84% (faldaprevir 240 mg without LI).  Discontinuation rates were 1%, 4%, 11%, and 5% for the aforementioned treatment groups.

In the second study, the “SILEN-C2” trial, 290 non cirrhotic genotype 1 patients with either no response or partial response to previous treatment underwent a 48 week treatment trial with a similar design as the SILEN-C1. Results: SVR rates among partial responders were 32% (faldaprevir 240 mg LI), 50% (faldaprevir 240 mg without LI), and 42%(faldaprevir 240 mg BID/LI).  Among null responders, SVR rates were 21% (faldaprevir 240 mg LI), 35% (faldaprevir 240 mg without LI), and 29% (faldaprevir 240 mg BID/LI).  Adverse reactions were higher in those on higher doses and included anemia, rash, indirect hyperbilirubinemia, and nausea. Discontinuation rates were 6%, 4%, and 23% for the aforementioned treatment groups.

The third study provides a landscape of current treatment and emerging treatments.  Given the improvement in SVR among genotype 1 patients, the use of either telaprevir or boceprevir in combination with PEG/RBV is the “new standard of care” among adult patients with HCV.  Studies supporting telaprevir include the ADVANCE study, the REALIZE trial, and the OPTIMIZE study.  For boceprevir, its effectiveness was demonstrated with SPRINT-2, and RESPOND-2.

Both boceprevir and telaprevir, are NS3/4A serine protease inhibitors and are considered direct acting antivirals (DAAs). On the horizon:

  • Simeprevir -NS3/4A protease inhibitor.  Studies: PILLAR, ASPIRE.  SVR: 75-86% in treatment-naive patients. Once daily, no rash or increased anemia.  Hyperbilirubinemia can occur.
  • Faldaprevir -see above studies.
  • Danoprevir -NS3/4A protease inhibitor. Study: DAUPHINE. For genotypes 1 and 4. 100% SVR in genotype 4.  Rates of withdrawal with danoprevir were similar to placebo.
  • Daclatasvir -NS5A replication inhibitor. Study: COMMAND-1. For genotypes 1 and 4.
  • Sofosbuvir -NS5B polymerase inhibitor. Studies: PROTON, ATOMIC. For genotypes 1, 4, and 6.
  • Multiple DAAs in combination. Studies: MATTERHORN, INFORM-SVR, AVIATOR, ELECTRON, SOUND-2

Related blog posts:

What is Gluten-Free?

An excerpt from the National Foundation for Celiac Awareness Press Release:

NFCA Press Release about FDA Gluten-Free Labeling Rule

AMBLER, Pa. (August 2, 2013) – The National Foundation for Celiac Awareness (NFCA), a national non-profit organization dedicated to increasing diagnoses and improving quality of life for those with gluten-related disorders, is responding promptly to the U.S. Food & Drug Administration’s (FDA) final rule on gluten-free labeling by announcing new resources for gluten-free consumers to understand the federal regulations.

“For years, gluten-free labels have gone unregulated, putting our gluten-free community in danger,” said Alice Bast, President of NFCA. “We applaud the FDA for finally publishing a standard definition of gluten-free.”NFCA logo

The new regulations state that a food must contain less than 20 parts per million (ppm) of gluten in order to bear a “gluten-free” label. Researchers support less than 20 ppm as a safe threshold for a product to be consumed by individuals with celiac disease and other gluten-related disorders.

“Evidence-based research conclusively supports the 20 ppm level as a safety threshold for gluten-free products,” said Dr. Alessio Fasano, Director of the Center for Celiac Research at MassGeneral Hospital for Children in Boston. “We welcome the new FDA regulations, which will bring us in line with gluten-free labeling regulations for millions of people around the world.”

Related Links:

Thanks to Kayla Lewis for forwarding the press release.

 

TNF Antagonists and Psoriasis

Using data from the adverse event reporting system (AERS) from the FDA, the authors of a recent report identified a large number of psoriasis rashes which developed among patients receiving tumor necrosis factor α (TNF) antagonists (Inflamm Bowel Dis 2013; 19: 1164-72).

From more than 13 million AERS reports (2004-2011), a total of 5432 reports of psoriasis were noted: 1789 for infliximab, 3475 for adalimumab, and 168 for certolizumab compared with 88 for a control group which consisted of the following medications: propranolol, melamine, and lithium. While the absolute number for certolizumab is lower, the relative risk is similar to infliximab when adjusted for frequency of usage.

The AERS database relies on voluntary reporting and there are numerous reporting biases.  Given that AERS captures only a fraction of all true adverse events, the authors extrapolate that more 15,000 psoriasisiform adverse events occur each.  They note that these reactions typically occur in individuals without a personal or family history of psoriasis.  The onset is variable, but typically occurs 9-11 months after initiating therapy.

Additional references:

  • -IBD 2011; 17: 2512.  n=50.  Skin reactions with adalimumab.  62% of pts develop skin reactions: eczema, acne-like dermatitis, psoriasis-like (6 of 50).  Adalimumab d/c’d in 22%.
  • -JPGN 2010; 52: 230. 6 of 73 pts (8%) developed IFX-induced psoriasis -managed with topical Rx.
  • -Clin Gastro & Hep 2010; 8: xxiv. Image of psoriaform rash assoc with infliximab
  • -Aliment pharmacol Ther 2009; 29: 921-27. Review of psoriaform rash assoc with infliximab. Majority improved when TNF stopped.  Options: Rx w steroids for 3 days around Rx or add MTX.
  • -NEJM 2009; 361: 496. Review of psoriasis.

Unrelated link:

For those of you who do not have teenage sons, perhaps you are not familiar with Jimmy Kimmel’s:  This Week in Unnecessary Censorship – YouTube

What to do with ALTEs?

While apparent life-threatening events (ALTEs) in infants are quite disturbing, the best management for these events is far from clear. A recent systematic review of ALTEs in infants was undertaken and included studies from 1970-2011 (J Pediatr 2013; 163: 94-9). The authors ultimately identified 37 relevant studies: 18 prospective observational studies and 19 retrospective observational studies.

Results:

  • None of the 37 studies yielded “a high level of evidence for diagnostic or prognostic investigations.”
  • Risk factors for ALTE: prematurity, previous ALTEs, and suspected child maltreatment.
  • Routine screening for gastroesophageal reflux, meningitis, bacteremia, and seizures are “highly unlikely to be helpful in patients who are well-appearing and have no other findings suggestive of a diagnosis.”
  • Testing for GERD “is unnecessary in children with ALTEs.”  “A positive test does not necessarily inform management because causation cannot be established.”  Patients with recurrent ALTEs “may benefit from pH monitoring in combination with symptom recording.

Additional references:

NASPGHAN Consensus guidelines on GERD (2009)

Link: Gastroesophageal Reflux Disease in the Pediatric  – NASPGHAN.o

  • In premature infants, a relationship between GER (i.e. reflux) and pathologic apnea and/or bradycardia has not been established.Despite a lack of convincing evidence, if pathological apnea occurs in the face of pre- existing reflux, then the following two statements are the most common features:
  • Although reflux causes physiologic apnea, it causes pathologic apneic episodes in only a very small number of newborns and infants.
  • When reflux causes pathological apnea, the infant is more likely to be awake and the apnea is more likely to be obstructive in nature.
  • A diagnosis of an acute life-threatening event (ALTE) warrants consideration of causes other than GER (i.e. reflux).Reflux of gastric acid seems to be related to ALTEs (episodes of combinations of apnea, color change, change in muscle tone, choking, and gagging) in < 5 % of infants with ALTE. 
  • -J Pediatr 2009; 155: 516. Bradycardia not improved in preemies treated for GER. n=18. Editorial 464 urges not using GER Rx in neonates –outside clinical trials.
  • -J Pediatr 2009; 154: 374. Apnea associated with reduction in LES tone in premature infants; therefore, GER may be secondary to apnea rather than the reverse. Small study -12 apneic event in 7 infants.
  • -J Pediatr 2008; 152: 365. Compared risk factors with SIDS. One of 153 (0.6%) with ALTE died.
  • -Pediatrics 2005; 116: 1059 & 1217 (editorial). Apnea in preemies is unrelated to GER.
  • -Pediatrics 2004; 113: e128-132. Apnea is unrelated to GER in most preemies; airway problems due to GERD is hard to establish.
  • -J Pediatr 2000; 137: 321 & 298. Poor temporal association between GER & apnea in ALTE patients.
  • -J Pediatr 2001; 138: 355. Metoclopropramide/cisapride do not help apnea in preemies with GER
  • -Pediatrics 2002; 109: 8-11. GER does not cause apnea of prematurity.

Saving Livers and Saving Lives -An Insider’s View

Pediatric Hepatology hep26580

The link above provides a terrific overview (Hepatology 2013; 58: 458-476) of the development of pediatric hepatology as a subspecialty.  For someone who was incredibly fortunate enough to train in the mid-1990s (right place, right time, right colleagues), I enjoyed finding out more about the decades that preceded my fellowship.  In addition, the article provides insight into the personal background of one of my mentors (thanks for Figure 1) and about a few patients that provided the clinical challenge for furthering the understanding of the pathophysiology of hepatobiliary disorders.

Remission in Crohn’s Disease

A recent article highlights the issue of remission in Crohn’s disease (CD) (Inflamm Bowel Dis 2013; 19: 1645-53).

As noted in previous blog entries (see links below), improvements in remission with ImproveCareNow and with previous drug trials have several limitations due to the current definition of remission.  Currently, even during periods of clinical remission (defined currently mainly by symptoms), laboratory or endoscopic evidence of persistent inflammation can be seen.  Persistent inflammation is likely to lead to progressive bowel damage. With the advent of more effective treatments as well as better biomarkers, a more objective measure of remission is needed.

“Remission is an evolving concept in CD. At its most fundamental level, remission should be a state with little or no risk of disease progression, likely implying the absence of biological evidence of inflammation.”

The authors proposed definitions of remission based on whether the patient has “early” disease or “late” disease.  Early disease “may be defined as disease duration ≤18 months without previous exposure to immunosuppressants or biologics.”

Early disease:

  • Biologic remission (inflammation control): a) mucosal healing on colonoscopy (no ulcers with the exception of a few aphthous ulcers <5 mm in diameter) and/or b) improvements in serum and fecal biomarkers: CRP < 5 mg/L, fecal calprotectin <250 mcg/g
  • Clinical remission in practice (symptom control): complete absence of symptoms; 1-2 formed stools per day without abdominal pain.  In a clinical trial, CDAI <150 points.
  • Outcomes: no disease progression or complications, normal quality of life

Late disease:

  • Biologic remission (inflammation control): a) mucosal healing on colonoscopy (no ulcers with the exception of a few aphthous ulcers <5 mm in diameter) and/or b) improvements in serum and fecal biomarkers: CRP < 5 mg/L, fecal calprotectin <250 mcg/g
  • Clinical remission (symptom control): a: inflammatory symptom improvement (may have residual symptoms due to previous damage or surgery). In clinical trial, CDAI 150-220 points.
  • Outcome: stabilization of noninflammatory symptoms and no progression of structural damage, improved quality of life

The authors goal is to rework remission to include symptom control and histologic/mucosal healing.  This concept is not novel.  Investigators in the adalimumab EXTEND study coined the term “deep remission.” This term referred to patients with both CDAI remission and complete mucosal healing.  Patients who achieved deep remission had improved outcomes, including fewer hospitalizations and fewer surgical resections (Gut 2010; 59: A80).

Bottomline: Improvements in both objective measures of biologic inflammation along with resolution of clinical symptoms are needed to change the long-term outcome for patients with Crohn’s disease.  The definition of remission should reflect this reality.

“When you can measure what you are speaking about and express it in numbers, you know something about it; but when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind” –Lord Kelvin 1883

Related blog entries:

Fewer Intern Hours & No Change in Patient Safety

Excerpt from Gastroenterology & Endoscopy News (Shorter Workweeks for Interns Do Not Promote Patient Safety) :

A policy to shorten the workweek for interns in the United States has failed to improve their quality of life and has possibly put patients at greater risk for medical errors, a new study has found (Sen S et al. JAMA Intern Med 2013;173:657-662).

The 2011 policy change, recommended by the Accreditation Council for Graduate Medical Education, capped at 16 continuous hours the longest shift a first-year resident could work in the hope that doing so would ease the strain on physician trainees.

But although the new rules have shortened the typical intern’s workweek from 67 to 64.3 hours, they haven’t encouraged residents to sleep more, helped them to avoid depression or increased their overall sense of well-being, the study found…The study was based on email surveys of 2,323 residents …entered training in 2009, 2010 and 2011, after the rule change.

“Given that increased sleep was a key [mechanism] through which the new duty-hour restrictions were intended to improve the health of residents, the lack of such an effect in the postimplementation cohort in our study is a cause for concern,” wrote the authors, led by Srijan Sen, MD, PhD, a psychiatrist at the University of Michigan in Ann Arbor. “Designing work schedules that account for circadian phase and explicitly training residents on practices to increase sleep time and improve sleep quality may be necessary.”