2018-19 TOW #29: Food allergy

Next week’s topic is on food allergies, a hot topic with the recently evolving literature and recommendations.

Materials for next week:

A few take-home points:

  1. What’s the epidemiology? As many as 1 in 13 children is thought to have a food allergy. Along with other allergies, the rate of rise of food allergies has been rapid. While well-meaning, the recommendation to delay introduction of foods probably led to an increase in allergy development as children were sensitized through exposure, such as through the skin. Generally, the most common allergens in childhood include egg, milk, peanut, tree nuts, wheat, soy, fish, shellfish,and sesame.
  2. How do we prevent food allergies? We’ve had a recent dramatic change in practice in solid food introduction: we are now recommending solids foods between 4-6 months to “teach the body” during the window of time when less reaction occurs. We should recommend introducing a variety of foods, including foods containing peanuts, eggs, and tree nuts soon after children start solids. Mixing a bit of water into peanut butter to make it soupy is one way to expose infants to peanut butter (more recipes/options in the appendices here). For eggs, baking them into foods denatures the proteins so may be the best initial exposure for babies with a higher food allergy risk based on family history. Also egg yolks are less allergenic than egg whites. Breastfeeding for at least 4 months and when new foods are introduced is associated with decreased risk of atopy, though doesn’t necessarily prevent food allergies.
  3. How do we diagnose food allergies? Symptom reaction to the food: usually these are Type-1 IgE-mediated hypersensitivity reactions that happen within minutes of ingestion: including skin (most common), oral or nasal mucosa, GI, or respiratory reactions, or a combination of these in full anaphylaxis. Typically symptoms resolve within 4-12 hours. There are also Type-4 cell-mediated hypersensitivity reactions to food, such as milk protein allergy, that cause mostly GI symptoms. Some children avoid foods due to symptoms, so pay attention to these behaviors. Once a reaction has occurred, testing may help evaluate the allergy but are not fully diagnostic. A skin-prick test for food is recommended but it’s not 100% specific, with high false positive rate. Serum specific IgE testing is useful for patients who cannot discontinue antihistamine therapy or for those with extensive skin disease or dermatographism. An oral food challenge is considered the gold standard and may be part of making the diagnosis when it’s in question.
  4. How do we manage food allergies? Strict avoidance of the allergenic food is the primary approach. Egg and milk may be tolerated in cooked forms, with exposure helping build tolerance to other forms of the foods. Treatments for allergies are evolving and it’s exciting to see emergence of more success with new immunotherapies.
  5. How do we treat reactions and prevent death from anaphylaxis? Food-induced anaphylaxis is a “rapidly progressive, multiorgan allergic reaction that can result in death.” Recognition and quick response is essential to save lives. Anaphylaxis symptoms may be uniphasic, biphasic, or protracted. In all cases, most important is rapid treatment with IM epinephrine. Repeated epinephrine dosing should be used when symptoms progress or response is not optimal. All patients with any moderate to severe IgE-mediated reactions to foods should have self-administered IM epinephrine available. Mild skin-only reactions may be treated with diphenhydramine.

2018-19 TOW #28: Constipation/Encopresis

Next week we are reviewing constipation/encopresis. Talking about poop may be uncomfortable for our patients, yet we know how important it is for us to be comfortable addressing this issue.

Materials for this week:

Review on constipation in pediatrics:

  1. Epidemiology: Constipation accounts for 3–10% of visits to general pediatric clinics and up to 25% of referrals to pediatric gastroenterologists worldwide. Genetics plays a role, and social/ environment risk factors include low consumption of fiber, low levels of physical activity, living in a highly-densely-populated community, and low parental education. In >90% of children with symptoms, no obvious organic cause is found.
  2. Clinical definition: Pediatric functional constipation is defined as at least 2 of the following (frequencies in parentheses): Two or fewer defecations per week (75%), At least one episode of fecal incontinence per week (75-90%), Stool retentive posturing (35-45%), Painful or hard bowel movements (50-80%), Large diameter stools that could obstruct the toilet (75%), Presence of a large fecal mass in the abdomen or rectum (30-75%).
  3. Physical exam: Many have normal exams. 30-50% have a palpable abdominal mass. 5-25% have anal fissures or hemorrhoids. 3% have anal prolapse. >40% have fecal impaction.
  4. Work-up: Diagnosis can be made with history and exam and rarely requires additional work-up, except for more severe persistent cases. Concerning history would include passage of meconium >48 h after birth, bloody diarrhea, fatigue, fever, bilious vomiting, and eczema.
  5. Management: a 4-step approach is recommended with 1) education, 2) disimpaction, 3) preventing stool reaccumulation, and 4) behavioral therapy. Oral laxatives with Polyethylene glycol (PEG) (1-1.5g/kg/day) or rectal enema are considered equivalent first-line therapy for disimpaction. Maintenance laxatives are needed for most children for months to years. In my experience, there also may be a role for increasing fiber through supplements, such as products like Benefiber, especially for more minor constipation, or when laxatives lead to incontinence. Protocols and education are provided through our GI department including their constipation protocol.

2018-19 TOW #27: Bone Health

As we are in the thick of winter and lacking sun, it’s a good time to review optimizing bone health for children. The AAP updated its statement in 2014 with higher RDA levels for vitamin D for children, due in part to no “safe” sun exposure. Nonetheless, outdoor play time is still recommended, and can help with bone health, as Drs. Pooja Tandon and Kyle Yasuda (UW professor emeritus and current AAP president) wrote about recently in the Seattle Times!

Materials for this week:

Take-home points:

  1. What are the optimum levels for intake of calcium and vitamin D? Recommended daily allowances (RDA) for vitamin D for children are 400 IU 0-12 months, 600 IU >1 year. Calcium RDAs also increase with age: 700mg for 1-3 yo, 1000 mg for 4-8 yo, and 1300mg for 9-18.
  2. Why are we concerned about these nutrients? In addition to rickets, low Vit D and calcium intake is linked to increased fractures later in childhood/adolescence (and adulthood). Despite the many studies linking low vit D to a host of other conditions, we do not have reliable evidence that they are in fact causally linked.
  3. Who is at highest risk for low levels? Children at higher risk for low vit D include youth with darker pigmented skin, overweight youth, inadequate dietary intake, living in northern latitudes (>33 degrees -that’s us!), taking certain medications (anticonvulsants, steroids, antiretrovirals). Those at high risk for low bone density include children who do not do bone-density strengthening exercise, particularly children who require wheelchairs.
  4. Who should be screened with blood tests? Testing for Vit D levels is not routinely indicated; AAP recommends only for conditions associated with reduced bone mass (malabsorption syndromes, CP, taking medications that interfere with absorption), or recurrent low-impact fractures. (*note Endocrine society also recommends for children with dark skin or with obesity).
  5. When should we recommend supplements? It’s better to receive Vit D and calcium in dietary sources, but there are few sources of vit D in the diet: mainly fortified milk (and some orange juice and yogurts). Supplements are indicated for breastfed babies (until drinking at least 1L per day of fortified formula/milk), and those with low dietary sources or high risk for low bone density. Among children who do not drink much milk (including one of my own kids), I recommend a multi-vitamin supplement with calcium and vitamin D.

2018-19 TOW #26: Childhood Obesity

As the new year begins, we can harness the season’s focus on wellness to offer families encouragement with healthy behaviors. Obesity prevention and intervention is a topic close to my heart, so I am excited to highlight our great local resources. We have many wonderful obesity research experts in our clinics, including Drs. Lenna Liu, Jay Mendoza, and Pooja Tandon. A big thanks to Dr. Allison LaRoche for her help updating materials for this topic. Feel free to email any of us with questions!

Teaching materials for this week:

Take-home points for this week:

  1. What’s the epidemiology of child obesity?: While some progress is being made, with promising data on declines among preschool youth, overweight/obesity rates remain high at 1 in 3 children with a BMI at or above the 85th percentile. Etiology of obesity is multifactorial including important environmental contributors that are affected by social determinants. As pediatricians, we should acknowledge the equity issues reflected in higher rates of obesity among those with more social disadvantage including low-income families, and Hispanic, African American and American Indian youth.
  2. What focused messages can we share in clinic? Focusing on behaviors/ environments that support healthy weight starts from infancy. Teach the Division of Responsibility for feeding in which “parents provide, and child decides.” The parent is responsible for what, where, and when food is served, and the child is responsible for how much to eat. We can use 5210 goals to help guide healthy weight behaviors: 5 fruits and veggies per day, watch no more than 2 hours of screen time, get 1 hour or more of physical activity, and have 0 sugary drinks. The Let’s Go! 5210 campaign was started by a pediatrician in Maine, and they have some great resources like Phrases that Help and Hinder. Families should choose their own goals through motivational interviewing, which has been shown in randomized trials in pediatrics to work in improving weight trajectories.
  3. How can we address this sensitive topic and avoid weight stigma in our practice? Recognize that obesity is highly stigmatizing and bias for weight is among the strongest biases culturally, even among children. We must be aware of our own biases as we treat patients and adopt inclusive, non-judgmental language, as recommended by Health at Every Size (HAES), which seeks to promote health-affirming behaviors and diversity of size, and to decrease weight stigma and emphasis. It’s helpful to acknowledge there are a lot of things outside the control of families (genes, community environment, etc), while also supporting specific behaviors that make a difference for health.
  4. What are the approaches for overweight and obese? For youth with BMI >85th percentile (overweight), and BMI> 95th percentile (obese), follow weight trajectory and family history to assess risk. Screening labs for metabolic risk factors (lipid panel, liver enzymes and A1c and/or glucose) are recommended starting at age 10 if obese (or overweight+risk factors). To promote healthy behaviors, refer to resources like the YMCA ACT! program – ACT! programs are enrolling this winter for 8-14 year olds around our area. We can also refer to SCH Wellness Clinics for multidisciplinary weight management from age 2 through adolescence. When metabolic problems are identified, see this article on treating comorbidities.
  5. What is the role of physical activity? For children at all weights, regular physical activity reduces the likelihood of comorbidities, even without decreasing BMI. It’s important for us to emphasize helping kids and parents find ways to be active and enjoy movement, no matter their body size.