Poorly-Conceived Allergy Testing Can Lead to Unnecessary Diet Restrictions and Complications

As noted in previous blog posts (see below), allergy testing can lead to unnecessary food restrictions which can in turn lead to numerous subsequent problems. Case in point: YV Virkud et al (NEJM 2020; 383: 2462-2470) report on A 29-Month-Old Boy with Seizure and Hypocalcemia

This boy presented with severe hypocalcemia, rickets, and seizures one year after allergy testing led to additional dietary restrictions. Also, his mother was a vegetarian. At time of allergy testing, IgE testing suggested allergies to milk, cashews, pistachios, egg whites, almonds, soybeans, chickpeas, green peas, lentils, peanuts, and sesame seeds. Many of these foods caused no symptoms with food challenges.

Besides working through the potential reasons for hypocalcemia, the authors make several key points:

  • Nutritional rickets is NOT a historical relic. Vitamin D deficiency appears to be increasing in high-income countries despite food-fortification strategies.
  • There are frequent misdiagnosis of food allergies. “Clinical and laboratory testing is severely limited by poor specificity…approximately 20 to 25% of children have positive IgE blood tests to specific food allergens, even though the true prevalence of IgE-mediated food allergy is likely closer to 6 to 8%.”
  • Avoid indiscriminate use of IgE blood testing. Allergen panels are “particularly problematic, because they often uncover false positives and lead to unnecessary food avoidance.” Individual IgE testing can be used to help confirm a diagnosis after an allergic reaction to a food trigger.
  • The most accurate diagnostic tool is an oral food challenge.
  • In children with food allergies, supplements are often needed to avoid micronutrient deficiencies and a low threshold is needed for involvement of dieticians.
  • Early introduction of foods can reduce incidence of allergies and periodic reassessment is needed to determine if a child has outgrown an allergy.
Xrays show generalized demineralization. The metaphyses show flaring (dashed arrow) and cupping (arrowbead). The physes are radiolucent and widened (asterisks).

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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

Most Popular 2020 Posts

I want to thank all of you who take an interest in my blog, particularly those who give suggestions, references, and encouragement. The following posts were the most popular from the past year.

Related post: Favorite Posts of 2020

Sandy Springs at Sunrise

Don’t Miss: Annual Aspen Conference on Pediatric Gastrointestinal Disease: Advances in Pediatric Liver Disease and Liver Transplantation (Online)

This year I had planned to go back to what many consider the best learning conference in our field, the Annual Aspen Conference.  This conference alternates yearly between GI topics and liver topics.  What has made this conference so great:

  • Intimate setting
  • Terrific faculty
  • Chance to enjoy the surroundings with friends and families after the lectures

Due to the pandemic, this year’s course will be curtailed and online.  While this changes the setting, it is still a great opportunity and a heck of a lot easier to attend. It will take place 1:00-2:30 pm Tues, Weds, and Thurs next week (July 14-16).  You can register for a day or for all 3 days. Course description and faculty are listed below.

Also, there is a pre-conference SCAVENGER HUNT.  (This appears to be mainly to help with promotion of the conference sponsors.) By participating, attendees will be eligible for  raffle prizes awarded during the webinar:
•  Snowmass Camelback
•  Snowmass Winter Gloves
•  Snowmass Hat
•  Snowmass Socks
The GRAND PRIZE is FREE 2021 CONFERENCE REGISTRATION!

Briefly Noted: Celiac Serology Normalization, Inflammatory Markers in Crohn’s Disease, Nutrition in Neurologically-Impaired

  • DM Isaac et al. JPGN 2017; 65: 195-99.

This retrospective study of 487 pediatric patients shows that it takes a long time to normalize celiac serology/anti-tissue transglutaminase antibody (TTG). The median time was 407 days for the 80.5% of patients that normalized their serology in the study time frame.  The time was 364 days for those who were considered adherent to a gluten-free diet.  Patients with type 1 diabetes were less likely to normalize their TTG levels. Faster normalization occurred in those with lower titers at baseline.

Related blog posts:

  • A Alper et al. JPGN 2017; 65: e25-e27

In this chart review, among 135 children, normal ESR and CRP were observed in 28% of children with Crohn disease and 42% of children with ulcerative colitis.

Related blog post: Do you really need both a ESR and CRP?

  • C Romano et al. JPGN 2017; 65: 242-64

This guideline paper details 31 recommendations (some with multiple parts) for the evaluation and management of children with neurologic impairment.  The recommendations include detailed evaluations including knee heights, skinfold thickness measures, DXA scan, routine micronutrient bloodwork, along with a low threshold for oropharyngeal dysphagia assessment.  The paper has recommendations for evaluations of reflux, constipation, and dental problems.  The authors suggest “considering use of enteral feeding if total oral feeding time exceeds 3 hours per day.”

Related blog post: Surgery for reflux works best for those who need it the least

Why Are So Many “Low Value” Endoscopies Performed?

After reading a few commentaries regarding value in medicine (which I will summarize tomorrow), it made me think a little more about value in pediatric gastroenterology.

I recently observed that a pediatric gastroenterologist in another group had a pattern of scheduling a lot of procedures.  In pediatric gastroenterology, we are not doing endoscopies to screen for malignancy.  The majority of children evaluated in our offices do not have organic disease.  In addition, there are a number of variables that can be used to select patients who are most likely to benefit from evaluation. In fact, much of our value comes from this selection process, because non-physicians can be taught to be endoscopic technicians.

My reaction to this volume of cases was that I thought either this practitioner was seeing a ton of patients, had been away and had accumulated a number of cases, or that this was low value care.  Though, another possibility is that the physician may be influenced by the “illusion of control” or “therapeutic illusion.” (NEJM full text: The Science of Choosing Wisely –Overcoming the Therapeutic Illusion).  According to a recent editorial, “When physicians believe that their actions or tools are more effective than they actually are, the results can be unnecessary and costly care.”

“The therapeutic illusion is reinforced by a tendency to look selectively for evidence of impact — one manifestation of the “confirmation bias” that leads us to seek only evidence that supports what we already believe to be true.”

Whatever the circumstances with regard to endoscopy volume, my intent is not to single out an individual or specific group.  My impression is that there are a lot more pediatric endoscopies being done these days and many are not needed.  While I recognize that clinicians recommend endoscopy with a great deal of variation, my suspicion is that those who use endoscopy less frequently are likely to see similar outcomes.  So, why are there so many low value endoscopies performed?

  1. The entire system is incentivized to do more procedures.  Physicians and hospitals are compensated more for doing these procedures.
  2. Families and sometimes referring physicians think these procedures are necessary.  In fact, there are studies that generally indicate higher levels of patient satisfaction when more diagnostic tests are done even if they are unnecessary.
  3. Physicians have a great deal of knowledge asymmetry in healthcare compared with families and it is expected that they will use their knowledge to help families pursue appropriate care.  While all physicians may have some lapses, some physicians skirt this part of their job.  One physician described this type of pediatric GI practice to me: “Scope first, think second.”

This blog has highlighted numerous aspects of health care economics.  Pharmaceutical companies and hospitals have been criticized for gaming the system.  The blog has discussed efforts to improve value like the “Choosing Wisely” campaign.  Though, it is interesting to note that even with this campaign, most physician groups rarely identified areas that would affect their financial bottom-line.  Among pediatric gastroenterologists, a frequent concern that I hear regards the overuse of CT scans by emergency room physicians.

When I take my car for repairs, I don’t want them doing an expensive overhaul unless it is really needed.  If a car needs a muffler change, but the repairman recommended a few thousand dollars of repairs, that would be outrageous.  Yet, in many cases with children, who are more precious than cars, the main difference with excessive endoscopic procedures, is that health insurance covers the majority of the costs.

I wonder too whether the frequency of endoscopy procedures actually discourages some families from having endoscopic procedures when they are clearly needed (eg. suspected celiac disease, suspected inflammatory bowel disease).

My take: Financial resources are limited.  When physicians do not help utilize resources well, this results in poor care, whether families realize this or not.  Ultimately, this will result in increased regulatory burdens for all physicians to more carefully justify what they are doing and/or result in efforts to eliminate financial incentives for unnecessary care.  However, as noted previously (Do deductibles work to improve smart spending on health care?), financial incentives often affect both low value and high value care.

Any readers care to comment?

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ViK Muniz Art -done completely from chocolate syrup

ViK Muniz Art -done completely from chocolate syrup -see the picture below for comparison.

The Vik Muniz piece is modeled after this photograph of Jackson Pollack

The Vik Muniz piece above is modeled after this photograph of Jackson Pollack

Picky Eating and Underlying Psychological Problems

Several news outlets have summarized a recent study which showed increased risk of psychological problems associated with being a picky eater.

An excerpt of a summary is from NBC news:

Picky eating, even at moderate levels, is linked with psychiatric problems, including anxiety and symptoms of depression in kids, according to a study published Monday in the journal Pediatrics. It found the mental problems worsened as the picky eating became more severe.

“We need to do a better job of giving advice to these parents,” Nancy Zucker, study co-author and associate professor of psychology at Duke University, told NBC News.

“The first take-home message is that you’re not to blame. The second take-home message is that it’s more complicated than we think.”

The study screened more than 1,000 children ages 2 to 5, and found 20 percent were picky eaters. The researchers stress this goes beyond kids who just hate broccoli or have certain dislikes.

More than 17 percent of kids were classified as moderate picky eaters: These children had a very limited range of foods they would eat and they would not try anything else, Zucker said.

About 3 percent were considered severe picky eaters: Their sensitivities to smell or taste were so strong that even eating outside of the home was difficult. As they get older, it could be hard for them to go out with friends or eat at school. …

The researchers also note the term “picky eating” may now be obsolete. They suggest the condition might be better described as avoidant/restrictive food intake disorder (ARFID).

Also from NPR: When a Child’s Picky Eating Becomes More Than a Nuissance

 

Reaching Consensus on Bariatric Intervention in Children and Adolescents

A recent medical position paper (Nobili V, et al. JPGN 2015; 60: 550-61) provides guidance for bariatric surgery intervention in children and adolescents with and without nonalcoholic fatty liver disease (NAFLD).

While the authors acknowledge that bariatric surgery can “dramatically reduce the risk of adulthood obesity and obesity-related diseases,” they advocate its use in adolescents with the following:

  • BMI >40 kg/m-squared with severe comorbidities: type 2 diabetes mellitus, moderate-to-severe sleep apnea, pseudotumor cerebri, or NASH with advanced fibrosis (ISHAK score >1)
  • BMI >50 kg/m-squared with mild comorbidities: hypertension, dyslipidemia, psychological distress, gastroesophageal reflux, anthropathies, NASH, impairment in activities of daily living, mild obstructive sleep apnea, panniculitis, chronic venous insufficiency, urinary incontinence
  • Additional criteria: have attained 95% of adult stature, failed behavioral/medical treatments, psychological evaluation perioperatively, avoid pregnancy for 1 year after surgery, will adhere to nutritional guidelines after surgery, informed assent from teenager (along with parental consent)

Key points:

  • “There is a lack of randomized controlled trials examining the effects of bariatric surgery on NAFLD or NASH.”  In Table 3, the authors provide a summary of 16 previous studies/outcomes; though none of the studies enrolled more than 60 patients.
  • In an adult prospective study with 381 patients (Mathurin P et al. Gastroenterol 2009; 137: 532-40), there was a significant decline in the severity/prevalence of steatosis and resolution of NASH at 1 and 5 years.
  • Bariatric surgery, in adult studies, have improved diabetes, insulin resistance, hypertension, and dyslipidemia.
  • Patients who have “undergone bariatric surgery show higher suicide rates than the general population.”  Psychological evaluation should be integrated with surgical decision.
  • Type of surgery: Roux-en-Y Gastric Bypass (RYGB) is favored by the authors; they also discuss studies with Laparoscopic Adjustable Gastric Banding (LAGB).  “RYGB and LAGB are the 2 main surgical procedures that have been used in pediatric obesity.  RYGB is considered a safe and effective option for adolescents with extreme obesity, as long as appropriate long-term follow-up is provided. LAGB has not been approved by Food and Drug Administration for use in adolescents, and there should be considered investigational only.”

It is interesting that the authors are so deferential to the Food and Drug Administration.  It is clear from their position paper that LAGB has similar evidence supporting its use in adolescents as RYGB.  They even note that it has potential for reversibility and “an excellent safety profile with a lower risk of postoperative vitamin deficiencies when compared with biliopancreatic diversion and RYGB.”

Bottomline: Given the continuation of the obesity epidemic, additional pediatric medical expertise will be needed to help evaluate adolescents for bariatric surgery and to follow them postoperatively.

Related blog posts:

Parenteral Lipids & Cholestasis –a Little More Data

A recent publication in JPGN indicates that resuming low dose soy-based parenteral lipid can be effective in patients (n=7) whose cholestasis had resolved on a fish oil-based parenteral lipid. It does not resolve the larger question of whether fish oil-based parenteral lipids are truly more effective than soy-based parenteral lipids (see previous blog links below).

Here’s the abstract:

Objectives: Intestinal failure associated liver disease (IFALD) contributes to significant morbidity in pediatric intestinal failure (IF) patients. However, the use of parenteral nutrition (PN) with a fish oil-based IV emulsion (FO) has been associated with biochemical reversal of cholestasis and improved outcomes. Unfortunately, FO increases the complexity of care: as it can only be administered under FDA compassionate use protocols requiring special monitoring, is not available as a 3-in-1 solution and is more expensive than comparable soy-based lipid formulation (SO). Due to these pragmatic constraints a series of patient families were switched to low-dose (1 g/kg/day) SO following biochemical resolution of cholestasis. This study examines if reversal of cholestasis and somatic growth are maintained following this transition.

Methods: Chart review of all children with IFALD who switched from FO to SO following resolution of cholestasis. Variables are presented as medians (interquartile ranges). Comparisons performed using Wilcoxon signed-rank test.

Results: 7 patients aged 25.9 (16.2,43.2) months were transitioned to SO following reversal of cholestasis using FO. At a median follow up 13.9 (4.3,50.1) months there were no significant differences between pre- and post-transition serum alanine and aspartate aminotransferases, direct bilirubin, and weight-for-age z-scores. Due to recurrence of cholestasis, one patient was restarted on FO after four months on SO.

Conclusions: Biochemical reversal of IFALD and growth were preserved after transition from FO to SO in 6/7 (86%) patients. Given the challenges associated with the use of FO, SO may be a viable alternative in select home PN patients.

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