IBD Updates December 2019

SR Gupta et al. JPGN 2019; 69: 544-50.  This article reports on preliminary experience in 54 children who received external (non-hospital) infliximab infusions. The average age was 17.6 years. The authors noted no serious safety concerns.  Prior to arranging these infusions, the authors insisted on the following:

  • Infusion services had to guarantee pediatric trained nurses with PALS certification
  • Emergency medications had to be available
  • A plan for emergency communication was arranged
  • Postinfusion communication would occur with each infusion

BN Limketkai et al. Inflamm Bowel Dis 2019; 25: 1828-37.  This study, using Truven Health MarketScan database (2007-16) reviewed proactive or reactive mucosal monitoring after biologic initiation in IBD.  Early (< 6 months) proactive monitoring (88% endoscopy-based) was performed in 11% (n=2195/19,899) of patients with Crohn’s and 12.8% (925/7247) of patients with ulcerative colitis.

  • “Early proactive monitoring was associated with a reduction in disease-related complications for CD (aHR 0.90) and UC (aHR 0.87) and predominantly driven by a reduction in corticosteroid use.”
  • Another interesting finding was that ~40% of patients had biologic therapy initiated without assessment of mucosal disease activity within 6 months.
  • The authors state that disease monitoring is typically more useful in CD than UC because with the latter, cessation of bleeding and diarrhea appear to be adequate surrogates.
  • This study was not able to assess whether a biomarker like fecal calprotectin would be suitable due to its low utilization.

RZ Cohen, BT Schoen, S Kugathasan, CG Sauer. JPGN 2019; 69: 551-6. In this chart review, the authors identified anti-drug antibodies (ADA) in 24.8% (n=58) of patients undergoing therapeutic drug monitoring (n=234) with both infliximab and adalimumab.  54% of this group had antibody suppression with dose optimization. Of note, 37 patients had detectable ADA at time of initial drug monitoring. Dose optimization was 10 mg/kg every 4 weeks with infliximab or 40 mg weekly with adalimumab. Patients who were switched to a second anti-TNF agent (n=23) were not more likely to develop ADA to the second agent (small sample size). Also, the authors caution that in the five patients with ADA levels (>10 U/mL), dose optimization failed and patients required a therapeutic switch. My take: This study provides some useful information about the frequency of ADA.  My view is that the actual drug level is more critical than the presence of ADA; though, the presence of high ADA often precludes the ability to deliver a therapeutic drug level.

Related blog posts:

Disclaimer: This blog, gutsandgrowth, assumes no responsibility for any use or operation of any method, product, instruction, concept or idea contained in the material herein or for any injury or damage to persons or property (whether products liability, negligence or otherwise) resulting from such use or operation. These blog posts are for educational purposes only. Specific dosing of medications (along with potential adverse effects) should be confirmed by prescribing physician.  Because of rapid advances in the medical sciences, the gutsandgrowth blog cautions that independent verification should be made of diagnosis and drug dosages. The reader is solely responsible for the conduct of any suggested test or procedure.  This content is not a substitute for medical advice, diagnosis or treatment provided by a qualified healthcare provider. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a condition.

More Details on Drug-Resistant E coli Transmitted by Fecal Microbiota Transplant

In June 2019, the FDA delivered a warning about the potential danger of transmitting drug-resistant E coli with fecal microbiota tranplantaion (FMT).  (FDA Warning for FMT)

A report on this issue has now been published: Z DeFilipp et al. NEJM 381: 2043-50, editorial M Blaser pgs 264-6.

The authors describe two patients, a 69 year-old with cirrhosis and a 73 year-old sp stem cell transplantation, who developed bacteremia due to transmission of a drug-resistant (extended-spectrum beta-lactamase [ESBL]) E coli following FMT which was delivered by oral capsules. The latter patient died from sepsis. The two patients had a genomicly-identical strain isolated that was also found in the donated aliquot.

In the commentary, a couple of important points:

  • “Up to now, the complications have been infrequent [from FMT], and for recurrent C difficile infection, the benefits of FMT clearly outweigh the risks; however, as the use of FMT is broadened and more compromised patients are treated, complications may be more frequently observed.”
  • “In the short term, improved and uniform screening of FMT material is needed to reduce the risks.”

My take: Both of these patients who became developed bacteremia were at risk for more severe infections.  However, we need to remain aware that severe complications can and do occur with FMT.  In context, though, there are risks of severe complications from routine use of antibiotics as well.

Frontenac Hotel, Quebec City

Only 3% Make It Through the Donor Screening Process for Fecal Microbiota Transplantation

A recent letter (Z Kassam et al. NEJM 2019; 381: 2070-2) describes the arduous process involved in being selected as a stool donor for fecal microbiota transplantation (FMT).

In a previous blog (2015), it appeared that 17% of donors were accepted for FMT: Rejected! Most Stool is Not Good Enough for FMT This current review of the donor program from a stool bank (OpenBiome) prospectively evaluated 15,317 donor candidates from 2014-2018.

Key finding:

  • Only 3% (n=386) made it through all the steps to become donors

Reasons for exclusion:

Stage 1: common reasons for exclusion:

  • geographical -living too far away to donate regularly
  • BMI >30
  • social history
  • travel history
  • not in age range

Stage 2: “failing” the 200-item clinical assessment –common reasons for exclusion:

  • lost to followup
  • allergic disorders/asthma
  • receiving medications/supplements
  • mental health concerns
  • infectious disease history
  • social history/sexual history/other reasons

Stage 3: “failing” the stool and nasal screening which included (in 2016) carbapenem-resistant Enterobacteriacea (CRE), extended-spectrum beta-lactamase-producing organisms (ESBL) and MRSA. –common reasons for exclusion:

  • lost to followup
  • infectious disorders (including C diff in 7 patients)

Stage 4: “failing” serological screening

  • lost to followup
  • abnormal LFTs, CBC or infection

Related blog posts:

Island Ford, Sandy Springs, GA

How Genetics Influence Response to PPIs in Eosinophilic Esophagitis

About two years ago, James Franciosi presented research at NASPGHAN meeting indicating that the main difference between children with eosiniophilic esophagitis (EoE) who respond to proton pump inhibitiors (PPIs) compared to those who do not was related to their metabolism of PPIs and not related to the nature of their underlying EoE.

Related blog: #NASPGHAN17 Eosionophilic Esophagitis Session

Now, more has been published on this topic: EB Mougey et al. JPGN 2019; 69: 581-7.

In this study with 92 patients, data was collected from participants in a prospective clinical trial of high-dose PPI for EoE.

Key findings:

  • 57 (62%) were responsive to PPIs and 35 (38%) were not responsive to PPIs
  • Carriage of STAT6 allele variant rs1059513 predicted responsiveness to PPIs with OR of 6.16
  • Carriage of STAT6 rs324011 synergizes with CYP2C19*17 to predict PPI-nonresponsive EoE

Discussion: 

  • Carriers of CYP2C19*17 are more likely to fail PPIs for EoE.  Children with CYP2C19*17 gain of function “have a 7.7 fold better odds of failing PPI therapy” than noncarriers.
  • CYP2C19*17 effects “appears to be exerted within a specific range of PPI doses…and does not appear to exert influence at the low and high ends of this dose range.”
  • STAT6, which in this study is a cofactor, “upregulates transcription of CCL26 (eostaxin-3) 53-fold in esophageal eosinophilia relative to levels in peptic esophagitis and 490-fold over levels found in normal esophageal biopsies.”
  • PPIs effectiveness “does not correlate with esophageal” acid exposure; thus, its effects are mediated via an anti-inflammatory mechanism.

My take: This study indicates that genotype-guided dosing of PPIs for the treatment of EoE is likely to be worthwhile.

 

View from Yonah Mountain, GA

How Bad is Reflux in Children with Esophageal Atresia?

A recent retrospective study (FWT Vergouwe et al. JPGN 2019; 69: 515-22) with 57 children with esophageal atresia (EA) found most children have a normal reflux index.

This study, analyzing data between 2012-2017, reviewed all 24-hour pH-impedance (MII) studies in children at ≤18 months and 8 year olds with EA.  “All children with EA born in our hospital are offered a 24-hour pH-MII study at the age of 0.5 years and 8 years.”  In this institution, PPI treatment is given for at least 6 months after surgery. Of the 57 in the cohort, 20 had completed pH-MII at <18 months of age and 32 at age 8 years.

Key findings:

  • In children ≤18 months of age, median reflux index was 2.6% (abnormal in 2), median number of retrograde boluses was 61 (62% nonacid, 58% mixed)
  • In the older cohort (~8 years of age), median reflux index was 0.3% (abnormal in 4) and median number of retrograde boluses was 21 (64% nonacid, 75% mixed)
  • Overall, 10 of 57 children (17.5%) had GERD with reflux index >7% (n=6) or positive SI/SAP (n=4).  The authors note that much higher rates of GERD have been found in prior studies.  If they included children with fundoplication who were considered as having GERD (prior to fundoplication), then the GERD rate was 32%.

My take: This study showed that reflux in this cohort of children with EA was similar to the general population and likely indicates that a substantial portion of patients with EA do not need indefinite PPI therapy.  In children with more complex EA, PPI therapy is likely to be more beneficial.

Related blog posts:

Recent (November 4th) GI-Related Tweets:

Diabetes Mellitus Associated with Acute Recurrent and Chronic Pancreatitis

Briefly noted: MD Bellin et al. JPGN 2019; 69: 599-606.

Using the INSPPIRE database with 397 children with either acute recurrent pancreatitis or chronic pancreatitis, the authors examined the frequency of diabetes mellitus (DM).

Key findings:

  •  6% (n=24) had a diagnosis of DM. This is 30-fold higher than the general pediatric population
  • The group with DM was more likely to have elevated triglycerides (OR 5.21) coexisting autoimmune disease (OR 3.94) or pancreatic atrophy (OR 3.64)
  • The group with DM tended to be older with a mean at first diagnosis of acute pancreatitis of 12.9 years compared to 8.7 years in those who did not develop DM

Related blog posts:

 

Frontenac Hotel, Quebec City

Is CMV a Trigger for Necrotizing Enterocolitis?

Previously, it has been recognized that increased rates of necrotizing enterocolitis (NEC) have been associated with viral outbreaks (eg. rotavirus, norovirus) (J Pediatr Surg. 2004;39:453–7 , 2010l;29: 644-7.).

A more recent study (S Panesso-Gomez et al. J Pediatr 2019; 214: 34-40) examines the association between cytomegalovirus (CMV) and NEC.

Key Findings:

  • In this retrospective cohort (2000-2016) with paraffin-embedded samples, the authors detected CMV by PCR or immunohistochemistry (IHC) in 7 (4%) of 178 infants with either NEC (n=143) or spontaneous intestinal perforation (n=35).
  • PCR was more sensitive and was positive in all 7 detected cases whereas IHC identified CMV in 4 of the cases.

One of the limitations of the study was the lack of a control group, though previous reports have found congenital CMV in 0.4% of preterm infants with very low birth weight (<1500 g) and in 0.5-1% of all liver births.

My take: This study shows an association between the presence of CMV and NEC; hence, CMV may be one of many factors which increase susceptibility to NEC.

Related blog posts:

 

 

Yonah Mountain

Esophageal Disorders: POEM in Kids, Mitomycin C for Refractory Strictures

At our recent national meeting, Dr. Peter Kahrilas indicated that POEM (Per-oral Endoscopic Myotomy) was now the treatment of choice for most adults with achalasia (#NASPGAN19 Postgraduate Course -Part 3).

A Chone et al (JPGN 2019; 69: 523-7) provide recent multicenter retrospective data on POEM in the pediatric age group (mean age 14 years), n=117.

Key findings:

  • Clinical success, defined as Eckardt score ≤3 during followup, was achieved in 90.6% of cases. The Eckardt score was >3 in 5 (4.3%) and data was missing in 6 (5.1%)
  • Adverse events included 1 case with significant bleeding, 2 cases of aspiration pneumonia (related to anesthesia), 1 esopleural fistula (managed endoscopically), and 6 mild AEs (4 mucosomtomies, 2 subcutaneous emphysema)

Additional related blog posts:

D Ley et al (JPGN 2019; 69: 528-32) provide retrospective data on 39 patients, median age 19 months, with refractory esophageal strictures which were treated with mitomycin C.  The authors considered mitomycin C after a minimum of two previous dilatations.

Key findings:

  • Etiology: The majority had strictures/stenosis associated with esophageal atresia (n=25) followed by caustic ingestion in 9.
  • Number of stenosis: The majority (n=35) had a single stenosis.
  • In 26 patients (67%), topical application of mitomycin C was considered a success based on a reduction in the number of dilatations.  In this group, the number of dilatations dropped from 102 to 17 over a comparable period.
  • 16 (41%) never required further dilatation following mitomycin C application

My take: This study provides some of the best evidence that mitomycin C may be helpful.  Long-term followup and more studies are needed.

Related blog posts:

Disclaimer: This blog, gutsandgrowth, assumes no responsibility for any use or operation of any method, product, instruction, concept or idea contained in the material herein or for any injury or damage to persons or property (whether products liability, negligence or otherwise) resulting from such use or operation. These blog posts are for educational purposes only. Specific dosing of medications (along with potential adverse effects) should be confirmed by prescribing physician.  Because of rapid advances in the medical sciences, the gutsandgrowth blog cautions that independent verification should be made of diagnosis and drug dosages. The reader is solely responsible for the conduct of any suggested test or procedure.  This content is not a substitute for medical advice, diagnosis or treatment provided by a qualified healthcare provider. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a condition.

Lincoln Park, Chicago

Why Fewer Children Have Immune-Tolerant Hepatitis B Infection Than Previously

A recent study (KB Schwarz et al. JPGN 2019; 69: 588-94) highlights the chronic hepatitis B virus (HBV) phenotypes from a large pediatric North American cohort (n=371).

  • Immune-tolerant HBV was define by HBe-Ag-positivity along with normal ALT levels.
  • Inactive carrier were HBe-Ag-negative with low HBV DNA/normal ALT.
  • Chronic hepatitis B (HBeAg positive and HBeAg negative) had high HBV DNA and abnormal ALT values.
  • Indeterminant HBV had characteristics did not allow them to classified in these four categories.

Key findings:

  • If local laboratory normative values were used 36% of children would have been classified as immune-tolerant*.  However, this drops down to 12% if updated upper limits of normal (ULN) are used based on Figure 3.
  • Using updated ULN, 62% had immune active HBeAg+ disease, 12% with immune-tolerant HBV, 4% with immune-active HBeAg-negative disease, 6% with inactive carrier, and 16% indeterminant HBV.

*There are a few discrepancies between Figure 3 and the abstract data.  The abstract states that 82% would be considered to have chronic hepatitis B (this is 62% in figure 3). The abstract states that 35% were immune-tolerant based on local lab values.

The data presented were cross-sectional data at time of patient enrollment.

My take: this study shows that very few children in this cohort were immune tolerant based on more precise ULN values.  The authors note that the cohort who were immune tolerant were largely drawn from Asian children (most often infected perinatally).

Related blog posts:

Lincoln Park, Chicago

 

Surprising Genetic Mutations in Polyposis Study

A recent cross-sectional study (PP Stanich et al. Clin Gastroenterol Hepatol 2019; 17: 2008-15, editorial 1942-44) identified a high frequency of genetic mutations among adults with at least 10 colonic polyps (cumulative burden of either adenomatous or hamartomatous).

This study had 3789 subjects who underwent multigene panel testing (MGPT) from 2012-16.

  • All subjects had at least 14 CRC-associated genes tested: APC, BMPR1A, CDH1, CHEK2, EPCAM, MLH1, MSH2, MSH6, MUTYH, PMS2, PTEN, SMAD4, STK11, TP53
  • A subset had 3 more newly recognized polyposis genes: GREM1, POLD1, and POLE

Key findings:

  • A mutation in at least 1 gene was found in 13.7%
  • In those with fewer than 20 cumulative adenomas, 7.6% had a disease-associated genetic mutation with the majority (5.3%) being nonpolyposis CRC genes
  • Younger patients, 18-29, were more likely to have mutations in any gene.  For example, among patients with 10-19 polyps, these younger patients had a mutation in one of these genes in 27.8%; this is more than double the rate in any other age group.
  • Hamartomatous polyps, regardless of number, had a very high yield with genetic testing: 40% with 10-19 polyps and 72% with 20-99 polyps.

Limitations:

  • There is a referral bias in that the population was derived from a testing laboratory (Ambry)
  • In clinical practice, genetic testing frequently results in variants of unknown significance

My take: This study shows that genetic mutations are fairly frequent in patients with cumulative polyp burden of 10 or more, especially in younger age groups.  The surprising finding is the high frequency of nonpolyposis CRC genes.  Thus, in patients with adenomatous polyposis, testing beyond APC and MUTYH may be needed.

Related blog posts:

Atlanta Botanical Garden