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A Puzzling Thing Food Allergies. Mary Beth Feuling, MS, RD, CNSD Clinical Dietitian Specialist Children’s Hospital of Wisconsin Twin Cities District Dietetic Association Meeting September 14, 2010 (No financial relationships to disclose). Tonight’s Objectives:.
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A Puzzling ThingFood Allergies Mary Beth Feuling, MS, RD, CNSD Clinical Dietitian Specialist Children’s Hospital of Wisconsin Twin Cities District Dietetic Association Meeting September 14, 2010 (No financial relationships to disclose)
Tonight’s Objectives: • Discuss the nutritional impact of food allergies • Recognize and understand the role of the Dietitian • Understand allergy testing options and the impact on the food allergy patient • Discuss current issues, controversies and determine myths versus facts
What’s the story? • “Telling Food Allergies From False Alarms”(The New York Times) • “Is Your Kid Truly Allergic? Tests Add to Food Confusion”(The Wall Street Journal) • “Adverse Reactions to Food: Allergies & Intolerance”(Digestive Diseases) • “’Allergic Girl’ teaches how to eat out with allergies”(CNN.com)
What’s the story? • “This allergies hysteria is just nuts”(British Medical Journal) • “Children at risk in food roulette”(ChicagoTribune.com) • “Fear and Allergies in the Lunchroom”(Newsweek) • “Food Allergen’s Attack”(Food Service Director) • “Food Allergies Take a Toll on Families and Finances”(The New York Times)
Key Points to Remember • Medical Nutrition Therapy - Roadblocks • Registered Dietitian – Important Role • Degree of Nutrition Risk • Compounded with other Medical Conditions
History of Food Allergies • 80 years ago Carl Prausnitz (who was not allergic), injected serum from his fish allergic colleague Heinz Küstner into his own abdominal skin. • Prausnitz subsequently ate some cooked fish. After several minutes hives developed at the site of the serum injection.
History of Food Allergies • This clarified the fundamental basis of the allergic mechanism • There was a “serum component” responsible for allergy • In 1966 Ishizaka identified this as IgE • In 2003 first published anti-IgE trial in peanut allergy
How do we answer…? • Is it true that there’s more allergy now than when I was a kid? • Did I eat something while I was pregnant that caused my child’s allergy? I craved peanuts when I was pregnant… • Can peanut allergy be outgrown?
NHANES II vs NHANES III1976-80 vs 1988-94 Arbes SJ Jr et al: Prevalences of positive skin test responses to 10 common allergens in the US population: results from the third National Health and Nutrition Examination Survey. J Allergy Clin Immunol 2005;116:377-83
Sensitization Rates in the USResults of NHANES III • 54.3% of the population have at least 1 positive SPT • Of the allergens tested, prevalence was 2.1-5.5 times higher in NHANES III vs II • 8.6% population have a positive peanut test (not tested in NHANES II) Arbes SJ Jr et al: Prevalences of positive skin test responses to 10 common allergens in the US population: results from the third National Health and Nutrition Examination Survey. J Allergy Clin Immunol 2005;116:377-83
Prevalence Significant rise in atopic conditions in Westernized countries over the past 20 years Prevalence of peanut / tree nut allergy: 0.7% adults, 0.4% children: NY telephone survey Sicherer SH et al: Prevalence of peanut and tree nut allergy in the US determined by a random digit dial telephone survey. J Allergy Clin Immunol. 1999 Apr;103(4):559-62. Prevalence of shellfish allergy: 2% sensitivity to crustaceans (shrimp and lobster) 0.4% to finned fish Sicherer SH et al: Prevalence of seafood allergy in the United States determined by a random telephone survey. J Allergy Clin Immunol 2004;114:159-165.
Isle of Wight Popular from Victorian times as a holiday resort, the Isle of Wight is known for its natural beauty and as home to the Royal Yacht Squadron, home to poet Alfred Lord Tennyson and Queen Victoria's much loved summer residence. Its maritime history encompasses boat building and sail making through to the manufacture of flying boats and the world's first hovercraft.
Prevalence Rising prevalence (U.K.): 1246 children skin tested on the Isle of Wight Same geographic area evaluated 1989 & 1994 2 fold increase of reported peanut allergy 3 fold increase of peanut skin test sensitization Grundy J et al: The rising prevalence of allergy to peanut in children: Data from 2 sequential cohorts J Allergy Clin Immunol 2002;110:784-9
Prevalence • In 2007, 3 million children (4%) under 18 years of age • 18% higher than 1997 • Children = higher incidence of food allergies than adults • Children under 5 years of age = higher rates of food allergies than those > 5 yrs • Most children will “outgrow” their food allergies
Did I eat something while I was pregnant that caused my child’s allergy? I craved peanuts when I was pregnant…
Avoidance Diets and Prevention • Most studies show a protective effect on atopy by exclusive breast feeding • However, delaying initial exposure to cereal grains after 6 months may increase the risk of developing wheat allergy • Does low level exposure oral or via breast milk or topical promote sensitization or tolerance? Friedman NJ, Zeiger RS: The role of breast feeding in the development of allergies and Asthma. J Allergy Clin Immunol 2005;115:1238-48 Poole JA et al: Timing of initial exposure to cereal grains and the risk of wheat allergy. Pediatrics 2006;117:2175-82
Back to the Isle of Wight • In 1998 the UK issued advice that pregnant or nursing women with family history of atopy may wish to avoid eating peanuts • 858 births followed and SPT performed on 658 at age 2 • 65% mothers avoided PN (1st time moms more likely) • 13 / 658 positive: incidence risk 2% • In 10/13 (77%) of positive children, mothers had avoided PN Dean T, et al: Government advice on peanut avoidance during pregnancy-is it followed correctly and what is the impact on sensitization? J Hum Nutr Diet 2007;20:95-9
Is delivery by cesarean section a risk factor for food allergy? • Norwegian Birth Registry, 2803 children; 328 c-section births • In the atopic mothers 4 fold increase egg allergy • Positive association between C-section and persistent cow’s milk allergy (CMA) Eggesbø M et al J Allergy Clin Immunol. 2003 Aug;112(2):420-6 Allergy. 2005 Sep;60(9):1172-3
Summary of Recommendations for Prevention of Food Allergy • There is no evidence supporting avoidance or delays in food introduction in children who are not high risk • Definition of high-risk infants: • At least one parent or sibling with documented allergic disease • Maternal Lactation Diet: • No dietary restrictions • Exclusive Breast Feeding: • At least 4 months • Avoid Soy Formula: • No *There is no convincing evidence for using soy based infant formulas for allergy prevention. • Not Breast Fed or Supplemental Formula is needed: • use hydrolyzed formula • (extensively hydrolyzed/elemental is better than partially hydrolyzed; however must weigh benefit versus cost) • Delay introduction of solids: introduce solids between 4-6months of age. No current convincing evidence that delaying their introduction beyond this period, including those that are considered to be highly allergenic (egg, fish and foods containing peanut protein). (American Academy of Pediatrics Clinical Report January 2008; www.aap.org)
Timing of reaction: onset and duration Organs affected: localized vs systemic Location of reaction: home vs restaurant Severity of the reaction and response to treatment Prior history of food related reactions What was eaten? Amount eaten Allergy history: Asking the right questions
What is a food allergy? • Individual’s immune system is over-reacting to what is normally a harmless food • Response is related to the protein component of a food • Different from a “food intolerance” • Lactose intolerance: GI symptoms from milk sugar not protein – not an immune response. Often can tolerate 8 oz milk, low lactose cheese (cheddar, colby) and yogurt with live, active culture. • Can be life threatening
Immunologic Reactions to Foods IgE-Mediated Non-IgE Mediated • Protein-Induced Enterocolitis • Protein-Induced Enteropathy • Eosinophilic proctitis • Dermatitis herpetiformis • Eosinophilic esophagitis • Eosinophilic gastritis • Eosinophilic gastroenteritis • Atopic dermatitis • Oral Allergy Syndrome • Anaphylaxis • Urticaria
What is not a food allergy? • Oral Allergy Syndrome • Onset: older children and adults • Relation to hay fever (sometimes) • Symptoms • Oral scratchiness and redness around the lips • Treatment • Avoidance Common pollen – food associations (grasses = tomato; ragweed = melons, kiwi, banana)
What is not a food allergy? • Irritant Dermatitis • Not a food allergy • Acidic foods cause red patches around mouth and chin • Grapefruit • Orange • Tomato
Food Allergy in the United States • 6-8% of children under age 4; 4% of adults • Perception of the public 20-25% • 1 in 17 children under 3 years of age has food allergy • 8 foods account for 90% of all food-allergic reactions • Some food allergies persist throughout life Source: NCHS Data Brief, No. 10, October 2008
Major Food Allergens • Egg • Milk • Peanut/Tree nut • Fish/Shellfish • Soy • Wheat
Allergenic Foods • Almost every major food allergen identified is a protein or glycoprotein • Tend to resist denaturation by heat or acid • Less common: other legumes, sesame, poppy seed, sunflower seed, pine nuts, mustard seed
Table of cross reactive foods Sicherer SH: J Allergy Clin Immunol, 2001
How are food allergies diagnosed? • Blood tests • RAST (Radioallergosorbent test) • Serum IgE levels • Skin tests • Scratch tests (Skin Prick Test) • Food Challenge • Controlled • Parental observations • Clinical symptoms
Skin prick testing Photos with patient permission
Symptoms of Food Allergy (when exposed) • Hives • Eczema (dry, itchy skin) • Asthma • Vomiting, diarrhea, abdominal cramping • Red rash around mouth • Anaphylaxis (a life-threatening reaction)
Logarithm for the evaluation of suspected foodreactions Complete history and physical exam Skin prick testing (SPT) or R.A.S.T. Positive (?) Histor y Negative or low +RAST Food elimination diet Consider non - Nutritional evaluati on Consider GI evaluation Repeat SPT/RAST at intervals Nutritional evaluation Unchanged/increasing Decreasing levels Negative SPT or accidental ingestion Continue elimination diet without symptoms Food challenge Positive Negative Continue Oral tolerance elimination demonstrated diet Periodic food challenge -IgE diseases
Development of Tolerance • 10-20% Peanut allergic • 80% by 8-10 years of age for other foods • 50% by 5 years of age • Based on office food challenge
Fatalities in Anaphylaxis • Food anaphylaxis is the leading cause of anaphylaxis treated in ED: 30,000/yr with 150-200 deaths (Sampson et al. Pediatrics 2003 111:1601-8) • Peanut, tree nut, seafood account for most of these reactions
Fatal Food-Induced Anaphylaxis • 32 cases of fatal anaphylaxis reviewed • Most were adolescents or young adults • Peanuts, tree nuts caused >90% of reactions • 2/3 with asthma • Most did not have epinephrine available or did not use it. (Bock SA, et al. J Allergy Clin Immunol 2001;107:191–193)
Food-induced Anaphylaxis: Prevention • Learn to read product labels • Avoid high-risk foods that are more likely to contain a food allergen • (e.g, baked goods, foods from deli’s) • Avoid sharing food, utensils, or food containers • Must always be prepared to treat a reaction • Have an emergency action plan • Keep epinephrine on hand at all times • Train caregivers and teachers on epinephrine use • Wear MedicAlertbracelet
EpiPen® 2-Pak Twinject®or Adrenaclick® autoinjector
Question: The first step in the use of the EpiPen auto injector in the treatment of acute anaphylaxis is: A. Prep the skin with alcohol B. Grip the “pen” with thumb on the black cap C. Pull off the gray cap D. Take a deep breath and check your pulse
EpiPen/EpiPen Jr: Directions for Use Remove the Gray or Blue safety / activation cap. Black or Orange tip should NOT be touched. (Pressure will cause the needle to come forward and epinephrine will be ejected.)
EpiPen/EpiPen Jr: Directions for Use Place the Black or Orange tip near the fleshy outer portion of the thigh. It is not necessary to remove clothing or to prep the skin.
EpiPen/EpiPen Jr: Directions for Use Push firmly at a 90 degree angle to the thigh Hold for 10 seconds Call 911
Treatment of Food allergies The only treatment for food allergies at this time is to totally avoid ingestion and exposure to identified allergen. - Avoid the food - Careful meal planning - Read food labels - Ask about food preparation - Be prepared for emergencies
Allergist and Dietitian • Accurate diagnosis of causative foods • Institution of elimination/prevention diet • Assessment of proper emergency treatment and development of “action plans” • Treatment of associated atopic disorders • Assessment of nutritional status • Education
Nutrition and Food Allergies • Restricted diets will affect nutrient intake • Feeding a child safe food can be difficult with a food allergy diagnosis • Diagnosis of food allergies can increase stress for both the patient and family • With education, many, many, people live full and happy lives with food allergies!
Food allergies in children affect nutrient intake and growthL. Christie; R.J. Hine; J.G. Parker; W. Burks • Compared height, weight, and BMI of children with food allergies to control subjects • Results: • children with >2 food hypersensitivity (FH) were shorter than those with 1 FH • >25% children in both groups consumed <67% DRI for calcium, Vit. D, Vit. E • Less possibility of low calcium or vitamin D intake with nutrition counseling or if prescribed a safe infant/toddler formula or fortified soy beverage • Conclusion • Children diagnosed with food allergy need an annual nutrition assessment to prevent growth problems or inadequate nutrient intake J Am Dietetic Assoc;2002
Nutrition Principles • All children require same nutrients for growth, development, and health • Children with special needs may require more or less of specific nutrients • Nutrients can be adequately provided with a variety of feeding plans • Focus on “key” nutrients to decrease risk of nutrition-related problems
Nutrients Calories Protein Carbohydrate Fat Vitamins (13) Minerals (19) Water Key Nutrients Calories Protein Fat Calcium Iron Zinc Fluid Fiber Nutrition Principles