Category Archives: Pediatric Gastroenterology Intestinal Disorder

How long does it take the liver to recover from PNALD?

Posted on by

It takes a long time, even when there is no longer biochemical evidence of parenteral nutrition-associated liver disease (PNALD).  A recent study provides long-term data from a population-based, cross-sectional study on liver histology from pediatric intestinal failure (IF) patients (Hepatology 2013; 58: 729-38).  Patients were followed from 1984-2010.  IF was defined as having either >50% small bowel resection or need for PN >30 days.

The 38 IF participants had a median age of 7.2 years.  16 remained on PN after 74 months (range  2.5-204), 22 had weaned off PN 8.8 years (range 0.3-27) earlier after an average of 35 months of PN exposure.

Key findings:

  • Abnormal liver histology was present in 94% of patients on PN and 77% off PN.
  • Nearly 60% of patients on long-term PN had significant or severe fibrosis (Metavir stage ≥2).
  • Significant liver fibrosis and steatosis persisted after weaning off PN. That is, “liver histology remains abnormal up to 9 years after weaning off PN in the majority of IF patients.”
  • One patient off PN developed esophageal varices.
  • Risk factors for increased fibrosis: extensive small intestinal resection, (P=.002) loss of ileocecal valve (P=.048), and recurrent sepsis (P=.002).

Bottomline: While there have been important clinical advances in the management of IF, the data from this study indicate that many patients who have normal liver biochemistries continue to have abnormal liver histology.  Whether this will have an important clinical impact is not known.

Previous related blog entries:

Pediatric Consensus Statement: Perianal Crohn Disease

Posted on by

A recent report provides a useful reference for the often difficult care of pediatric perianal Crohn disease (JPGN 2013; 57: 401-412).

The statement reviews the background, etiology, presentation and classification systems. Most helpful are Figures 2 & 3.

Figure 2 provides an algorithm for assessment and treatment of perianal fistula.

  1. History/Physical (including rectal exam for stricture) along with colonoscopy
  2. Next either exam under anesthesia (with or without endoscopic ultrasound) or MRI
  3. Main treatments:
  • consider antibiotics, anti-TNF, and immunomodulators
  • in some cases a noncutting seton or fistulotomy will be needed
  • consider advancement flap in rectovaginal fistulae

Figure 3 provides an algorithm for assessment and treatment of perianal abscess.

  1. History/Physical (including rectal exam for stricture) along with colonoscopy
  2. Next either exam under anesthesia (with or without endoscopic ultrasound) or MRI
  3. Main treatments:
  • Incision and drainage
  • Noncutting seton if perianal fistula
  • Antibiotics
  • Treatment of intestinal disease

After outlining these algorithms, the report details the treatments.  Almost all treatments that are effective or questionable for Crohn’s disease are discussed.  The report reiterates that ‘corticosteroids must be used with caution in treatment of perianal fistula; studies have shown worse fistula outcomes for steroid-treated patients.

With regard to noncutting setons, the authors note that they do not prevent treatment with biologic agents and help prevent abscess formation.  They “usually deteriorate and fall out on their own in about 1 year.”  Medical therapy often allows for seton removal.

Ostomy diversion can be helpful in patients with severe perianal disease; however, “the risk of the ostomy becoming permanent is significant.”

Rectal strictures are typically dilated with multiple sessions with general anesthesia.  The goal is at least 18 mm in younger patients and at least 24 mm in adolescents.

Related blog post:

Previous references:

  • -Clin Gastro & Hep 2010; 8: 13.  Another algorithm.  For simple fistula, Rx w abx & medical (thiopurine or Remicade).  If not better, fistulotomy, &/or Rx as complex fistula.  For complex fistula, seton placement, abx, anti-TNF.  If not better, consider tacrolimus or proctectomy.
  • -JPGN 2010; 50: 99.  Perianal dz in young children may be due to autoimmune neutropenia.
  • -Clin Gastro & Hep 2009; 7: 1037.  MRI study of choice for perianal fistulas.  Algorithm: If superficial fistula, Rx c fistulotomy & Abx If deeper, noncutting seton c Abx, 6-MP +/- infliximab; if not effective, try tacrolimus; if not effective, surgery
  • -Ann Intern Med 2001; 135: 906-918.
  • -IBD 2008; 14: 1236.  Anal skin tag description
  •  -JPGN 2005; 41: 667.  Discusses several cases of highly destructive perianal dz. -Gastro 2003; 125: 1503-1507, 1508-1530.  Technical review.
  • -Gastro 2003; 125: 291.  Bourne test to detect occult bladder fistula.  Following nondiagnostic barium enema, urine can be collected, centrifuged,  and xrayed to determine if there is  a connection.

 

Abdominal distention – a medical mystery?

Posted on by

A recent ‘think like a doctor’ case in the NY Times involved a patient sent to a pediatric gastroenterologist for abdominal distention.  It’s worth a read (thanks to Ben Enav for sharing this reference).

http://well.blogs.nytimes.com/2013/09/05/think-like-a-doctor-the-gymnasts-big-belly/

With regard to bloating and distention, the ‘smartphrase’ that I use to discuss this issue with parents is based on the “5 Fs” that I learned during fellowship.  I decided to modify the phrase a little bit based on the above case:

” I reviewed the issue of bloating/distention with family. Typically, distention or bloating can be caused by “5 Fs” which include flatus (gas), feces (constipation), fluid, fat, and fetus/masses. Flatus can be caused by swallowing air (aerophagia), malabsorption (celiac, lactose intolerance, parasites), muscular discoordination (abdominal phrenic dyssynergia), and motility problems.”

Are there other etiologies that you discuss with your patients?

Practical Advice on Enteral Nutrition

Posted on by

In a previous post (NASPGHAN: Enteral Nutrition for Crohn’s Remission | gutsandgrowth), this blog provided a link to NASPGHAN information on enteral nutrition. Having reviewed this information further, I wanted to post some more information about one of the references which offers a terrific professional-quality 32 minute video (from IWK Health Centre in Canada).  This You-tube video on tube feeds provides interviews mostly from kids/family members along with some input by physicians and nutritionists; it is a fabulous resource for families weighing the option of tube feeds.  Around minute 23, a teen walks through the process of NG placement including advice on taping.  Around minute 31, a number of written tips are given like cleaning tubing with vinegar (& then rinsing with water).  According to the website there were only 275 views when I had clicked on this.  If that is accurate, it is a real shame.

Here’s the link:

Crohn’s Survival Guide: The Real Deal on Tube Feeds – YouTube

Other information from the NASPGHAN handout (which offers CME) in the link above:

  • Duration of enteral nutrition to induce remission: 8-12 weeks.  Enteral nutrition can induce remission in about 80% and is similar in effectiveness as corticosteroids.
  • Caloric needs: typically 120% of recommended daily allowance
  • Other foods? usually allowed water or clears like sodas, soup broth, and popsicles.  In some studies, up to 10% of energy intake as various other foods have been allowed; however, this creates a lot of difficulty monitoring.
  • Maintenance strategies: partial enteral nutrition (nighttime feeds only) can reduce recurrence.  More typical approaches included maintenance medication for long-term treatment, or enteral therapy in combination with maintenance medical therapy.  Alternatively, maintenance treatment can be instituted with cycles of 1 month exclusive enteral nutrition every few months.
  • What type of formula for NG tube? most commonly polymeric formulas
  • Refeeding syndrome: in children with severe malnutrition institution of tube feedings should be instituted more slowly over several days with electrolyte monitoring.

Tracking down a serial killer

Posted on by

Truth be told, I really do like the murder mystery genre.  In medicine, that particular type of drama is usually absent.  Nevertheless, it is fascinating when epidemiologists can track down an agent responsible for multiple deaths and widespread illness.  The latest example: Listeria monocytogenes (NEJM 2013; 369:  944-53).

This recent report isolated Listeria monocytogenes as the agent responsible for 147 outbreak-related cases in 28 states; there were 33 deaths.  The investigators used multistage epidemiological, trace-back, and environmental studies.  Molecular finger printing of the cases identified five distinct patterns which defined the outbreak cases. By comparing the outbreak cases to sporadic cases using the “Listeria initiative,” the authors were able to determine that uncut cantaloupe ingestion was much more common among the outbreak-related cases.  Subsequently, the source of the contaminated cantaloupe were traced back to a Colorado  farm that had switched to a different cleaning method in 2011.

Other data:

  • Only 7 cases (5%) were pregnancy-associated; 1 miscarriage occurred
  • The median age was 77 years in this cohort.
  • Most of the deaths were in the elderly, with only 2 deaths occurring in individuals less than 60
  • 143 patients required hospitalization

While this report discussed 147 outbreak-related cases, there were undoubtedly many more outbreak-related cases which were unidentified due to milder illness.

Bottomline: this report provides a framework for identifying outbreaks of contaminated produce.  It reinforces the need for good agricultural practices to minimize food borne-pathogen infections. It is a good read.

Related blog posts:

PPIs in Neonates –Helpful?

Posted on by

Acid suppression in infants has not been proven to be effective in reducing gastroesophageal reflux (GER) symptoms. In a systemic review, this was thought to be either “because the symptoms are not caused by GER or if due to GER, because the symptoms are caused by volume reflux, rather than acidity.”  This quote is noted in the background information of another study which came to the same conclusion (J Pediatr 2013; 163: 692-8).

The pharmaceutical-supported study enrolled neonates (n=52) at 3 centers with gestational ages between 28-44 weeks.  Half of the participants were randomized to esomeprazole (0.5 mg/kg/day) and half placebo.  GER symptoms that were required for enrollment included any 2 of the following:

  • apnea with or without bradycardia
  • apnea with or without oxygen desaturations
  • irritability/pain
  • vomiting/gagging

Participants underwent extensive testing with video monitoring, esophageal pH & impedance testing, and cardiorespiratory monitoring.  They were followed for 14 days.

Findings:

  • There were no significant differences in any GERD-related signs and symptoms.
  • The esomeprazole group had improvement in acid reflux parameters on testing at 7 days, including number of reflux episodes (35 –>23) and mean percent time with pH<4.0.  The latter change was -10.7% was statistically significant (p= .0017) compared to placebo group which had an increase in time with pH<4.0 (2.2% increase).
  • No new safety signals were identified.

Despite its widespread usage, the authors had difficulty enrolling a larger cohort.  The small sample size was one of the study’s limitations along with the 14-day study period.  This limitation also precludes conclusions regarding the safety of these medications in neonates.

Bottomline: this study adds to the growing body of evidence that proton pump inhibitors (PPIs) are not effective in infants with so-called ‘signs and symptoms of reflux.’  PPIs are effective at reducing acid exposure and could be helpful in proven mucosal disease (eg. esophagitis and gastritis).

Related blog entries:

Anti-TNF therapy for IBD

Posted on by

In the same issue as the vedolizumab phase 3 studies, there is a succinct review of tumor necrosis antagonist therapy (anti-TNF) therapy for IBD (NEJM 2103; 369: 754-62).

Useful points about IBD:

  • Prevalence of ulcerative colitis (UC) and Crohn’s disease (CD) in North America: 780,000 and 630,00 respectively
  • In first 10 years of CD, cumulative rate of surgery is 40-55%.
  • In first 20 years of UC, rate of colectomy is ~15%.
  • “Recent meta-analysis do not indicate that this drug (mesalamine) has any clinically relevant efficacy in patients with” Crohn’s disease.

Anti-TNF agents:

  • Agents for IBD include infliximab, adalimumab, certolizumab pegol, and golimumab.
  • No head-to-head comparisons have been studied, though the “clinical trials suggest similar efficacy among the available drugs.”
  • Newest approved anti-TNF is golimumab which is administered subcutaneously at a dose of 200 mg at week 0, followed by 100 mg at week 2 and then 100 mg every 4 weeks.
  • A “considerable number of patients with Crohn’s disease (10-40%, depending on selection criteria) do not have a clinically relevant response to currently available TNF inhibitors (primary treatment failure) and among patients with ulcerative colitis, this proportion may be as high as 50%.”
  • “In addition, only about one third to one half of patients with Crohn’s disease have a complete remission, and about two thirds of patients do not have a response that is sustained during 12 months of continuous treatment (secondary treatment failure).”  Many of these patients will respond to dose escalation.
  • The “annual projected cost of each biologic agent for a 70-kg patient with inflammatory bowel disease is approximately $19,000 in the first year and $15,000 in subsequent years.”  These figures exclude the costs associated with administration and dose escalation.

Areas of uncertainty according to the authors:

  • “The value of concomitant treatment with immunosuppressive agents and TNF inhibitors has been debated intensely.”  Combination therapy results in superior efficacy and lower rates of antibodies to anti-TNF agents.  However, “the benefit of combined treatment for more than 12 months is uncertain.”
  • “There are no data to confirm that it (top-down treatment) is actually superior to conventional step-up therapy in terms of disease progression”

Related blog links:

Coming Soon to a Pharmacy Near You (part 2)…

Posted on by

While yesterday’s post reviewed the data that indicate that vedolizumab is likely to be helpful for ulcerative colitis, only small improvements were noted for patients with Crohn’s disease (NEJM 2013; 369: 711-21, GEMINI 2 studies).

Vedolizumab, “a humanized immunoglobulin G1 monoclonal antibody to α4β7 integrin, modulates gut, but not brain, lymphocyte trafficking.”  The GEMINI 2 studies for Crohn’s disease were similar to the GEMINI 1 studies for UC.  However, even more medical centers (n=285) in more countries (n=39) and more patients (n=1115 with 967 receiving study drug) participated.

Baseline characteristics:

  • Median age: 36.1 years
  • Current Smokers: 26.7%
  • Disease location: 16.2% ileum only, 28.3% colon only, 55.4% ileum/colon
  • Median fecal calprotectin: 686 mcg/gram
  • Concomitant medications: 34.2% steroids only, 16.2% immunosuppressives only, 17% both steroids and immunosuppressives, 32.6% neither steroids or immunosuppressives
  • Median steroid dosage: 20 mg
  • Prior TNF antagonist ≥1:  61.8%
  • Prior surgery for Crohn’s disease: 41.8%
  • Prior fistulizing disease: 36.8%

Results:

  • At week 6, 14.5% of vedolizumab-treated patients and 6.8% of placebo-treated patients were in clinical remission (CDAI ≤150).
  • At week 6, 31.4% of study drug group and 25.7% of placebo group had a CDAI-100 response (≥ 100 point decrease in CDAI score).
  • Among patients with an induction response, 39% and 36.4% of vedolizumab every 8 weeks and every 4 weeks, respectively were in clinical remission at week 52, compared with 21.6% of patients assigned to placebo.
  • Vedolizumab-treated patients had increased serious adverse effects including serious infections.  Nasopharyngitis occurred more frequently.
  • Five deaths were noted during the study, four among the treatment group (Crohn’s/sepsis, intentional overdose, myocarditis, and septic shock).
  • No PML cases have been reported among the 3000 patients exposed to vedolizumab

While the response rate to vedolizumab was modest in Crohn’s disease patients, there are some factors that need to be considered in interpreting this data. Unlike in many trials (According to the study which you would never … – gutsandgrowth), this trial included patients with more disease severity.  The authors note that the effects of anti-integrin therapy could be relatively slower acting in Crohn’s disease due to the transmural nature of the disease.  An alternative explanation would be that the gut-selective targeting by vedolizumab is ineffective in most patients with Crohn’s disease due to the need for a more systemic inhibition with transmural disease.

Bottom-line: Among the small percentage of patients who have a response to vedolizumab at week 6, the rates of clinical remission at week 52 were significantly higher than those who received placebo.

Coming Soon to a Pharmacy Near You (part 1)…

Posted on by

Vedolizumab!

Two articles indicate that Vedolizumab will be an important agent for treating Ulcerative Colitis (UC).  The first article, NEJM 2013; 369: 699-710, describes two integrated studies (GEMINI 1 studies) in the use of this agent for induction and then for maintenance therapy of UC.

Background: Vedolizumab is a gut-selective blocker of lymphocyte trafficking (see previous post: Vedolizumab -another new IBD treatment | gutsandgrowth).  It is similar to natalizumab which was approved in 2008 for Crohn’s disease.  In phase 3 trials, natalizumab was demonstrated a response in 48% of patients with moderate-to-severe disease, but its large-scale use has been precluded by the potential for reactivation of the John Cunningham (JC) virus and progressive multifocal leukoencephalopathy (PML).

Study design: this study was a phase 3, randomized, double-blind, placebo-controlled study conducted at 211 medical centers in 34 countries from 2008-2012.  At baseline some of the assessments included blood tests, stool for enteric pathogens, chest radiography, stool calprotectin, QuantiFERON-TB Gold assay and sigmoidoscopy.  Intravenous vedolizumab was administered at a dose of 300 mg or placebo at days 1 and 15 during induction; also patients were stratified for glucocorticosteroids, use of immunosuppressives and prior use of TNF antagonists.  In total, 746 patients received vedolizumab and 149 received placebo.

Some of the baseline patient characteristics:

  • Mean age: 40.3 yrs
  • Median prednisone dose: 20 mg
  • Average fecal calprotectin: 899 mcg/gr.
  • Site of disease: 37% pancolitis, 13% rectum/sigmoid only, 37.9% left-sided disease, 12.2% disease proximal to splenic flexure.
  • Prior anti-TNF therapy: 48.2%

Results:

  • Induction: at week 6, 47.1% of vedolizumab and 25.5% of placebo-treated patients had a clinical response
  • Maintenance: at week 52, of patients randomly assigned to continue receiving vedolizumab, 44.8% every 4 weeks, 41.8% every 8 weeks were in clinical remission compared with 15.9% receiving placebo
  • Glucocorticoid-free remission at 52 weeks in 45.2% of patients receiving vedolizumab every 4 weeks, 31.4% receiving every 8 week treatment, and 13.9% of placebo-treated patients.
  • Figure 1 details important changes in Partial Mayo score, IBDQ score, Fecal calprotectin, and prednisone dose changes.  With regard to fecal calprotectin, at week 6 the median calprotectin level had dropped approximately 70%.  Smaller decreases were noted in patients continuing vedolizumab at week 52.
  • Safety: “no important differences” according to the authors between vedolizumab and placebo.  Specifically, there were no cases of PML; however, routine JC virus testing was not performed in this study.  Infusion reactions were seen in three cases (two with detectable antibody). a mild increase in nasopharyngitis was noted.
  • Cancer: 1.1% of placebo-treated patients developed a malignancy (1 colon cancer, 1 transitional-cell carcinoma, 1 squamous-cell carcinomas of skin) and 0.2% of vedolizumab (1 colon cancer)
  • Drug levels: mean vedolizumab concentrations at every 4 week dosing: 38.3 mcg/mL and at every 8 week dosing: 11.2 mcg/mL
  • Antibodies: 3.7% had samples that were positive for anti-vedolizumab antibodies at any time.  1% developed persistent antibody positivity.

Bottom-line: This large study shows that vedolizumab is effective in a large number of patients with UC, many who were refractory to other treatments, including anti-TNF agents.

Related blog posts: