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Efficacy & Safety of Abbreviated Oral Food Challenges in Ruling Out Food Allergy in a Pediatric Allergy Clinic
Abstracts AB83
J ALLERGY CLIN IMMUNOL VOLUME 131, NUMBER 2
Basophil Allergen Threshold Sensitivity, CD-Sens, and IgE Antibodies to Wheat, Hydrolysed Wheat, v-5 Gliadin and Timothy Grass in Relation to Wheat Challenge Outcome Nora Nilsson; Astrid Lindgrens Childrens Hospital, Stockholm, Sweden. RATIONALE: Wheat is one of the six most common foods causing allergy, requires a wheat free diet and has implications on the quality of life. The diagnosis of IgE-mediated immediate wheat allergy is currently based on oral food challenges which are time consuming, associated with risks and not frequently performed. An improved diagnostic workup is needed for wheat allergy. METHODS: Twenty four children, aged 1-19 years, with a wheat allergy diagnosis underwent a open wheat challenge. CD-sens and IgE- antibodies to wheat, hydrolysed wheat protein (HWP), v-5 gliadin and timothy grass were analysed and related to the challenge outcome. RESULTS: Of the 24 patients 12 children had a positive challenge. IgEantibodies to wheat, v-5 gliadin and HWP but not timothy discriminated between positive and negative challenge to wheat. The children reacting in challenge had a significantly (p<0.001) higher IgE-antibody concentrations and a tendency (p50.075) to higher wheat CD-sens values than the non-reacting children. Almost all children sensitized to timothy had a positive CD-sens to timothy, even those with low concentrations of IgEantibodies to timothy. Seven out of nine challenge positive children had a positive CD-sens to HWP and they all had an IgE-ab concentration to HWP above 10 kUA/L. Five children had IgE-ab to HWP but were negative in CD-sens to HWP. CONCLUSIONS: IgE-antibodies to wheat components and CD-sens could be useful aids in diagnosing and follow-up of wheat allergic children particularly when oral challenges are difficult to perform.
300
Oral Food Challenge: Experience in a Brazilian Food Allergy Outpatient Terciary Service Camila Pereira1, Leila Borges2, Renata R. Cocco1, Lucila Camargo1, Marcia Mallozi1, Dirceu Sole, MD, PhD3; 1Federal University of S~ao Paulo, 2Federal University of Sao Paulo, 3Federal University of Sao Paulo, Sao Paulo, Brazil. RATIONALE: To evaluate the results of oral food challenges (OFC) performed on followed patients in the Food Allergy Outpatient Clinic of the Federal University of S~ao Paulo. METHODS: Retrospective analysis of patients9 records submitted to OFC. From 169 analyzed tests, 4 were excluded due to incomplete data. RESULTS: From June/2007 to June/2012, 165 OFC were performed with cow9s milk (108), egg 18, soy 13, tartrazine 11, peanut 3, wheat 2, coconut 2, cow meat 2, nuts 1, fish 1, chocolate 1, sausage 1, pineapple 1 and wine 1. Male gender was predominant (67,2%), and the mean age was 4,6 year-old. Challenges were positive in 24,2% (n540). The main observed symptoms were cutaneous (80%), nasal (25%), gastrintestinal (22,5%), laryngeal (12,5%) and pulmonary (10%). Anaphylaxis occurred in 7 patients (17,5%), with cow9s milk 4, egg 1, nuts 1 and coconut 1. Anti-histamin was used in 31 patients (77,5%), associated with oral steroid in 18 (45%), and only 3 patients required intramuscular adrenaline (7,5%). Other allergic diseases associated: rhinitis (47,5%), asthma (40%), atopic dermatitis (37,5%) and drug reaction (0,05%). Positive serum specific IgE and/or skin prick test to the suspected food was observed in 59,6% of the patients. CONCLUSIONS: Cow9s milk, egg and soy were the most suspected foods, and cutaneous symptoms were the most common observed reactions. Despite the suggestive food allergy history and presence of specific IgE, about half of the performed OFC resulted negative, reinforcing the importance of this test as the gold-standard method for food allergy diagnosis.
301
Tolerance to Extensively Heated (Baked) Milk-Clinical and Immunologic Phenotype Hugh A. Sampson, MD, FAAAAI1, George N. Konstantinou, MD, PhD, MSc1, Jacob Daniel Kattan, MD1, Madhan Masilamani, PhD1, Beth D. Strong, RN, CCRC2, Elizabeth Paynter, MA3, Tee Bahnson, BS, MPH3, Anna H. Nowak-Wegrzyn, MD, FAAAAI2; 1Mount Sinai School of Medicine, New York, NY, 2Mt. Sinai School of Medicine, New York, NY, 3Rho Federal Systems Division, Inc., Chapel Hill, NC. RATIONALE: We previously reported that 70% of cow milk-allergic children tolerate baked-milk products. We sought to further define clinical and immunologic phenotypes of tolerance to baked-milk METHODS: Children with suspected milk allergy were challenged sequentially over 2 days (up to 2 foods per day) to foods baked under different conditions and containing increasing amounts of milk. Antibody concentrations were measured with UniCAPÒ; T regulatory cells were measured by flow cytometry; skin prick tests were done with commercial extract, unheated milk and boiled-milk. RESULTS: 136 children (70% males) were enrolled (median age: 7 yrs; inter-quartile range, 5-9 yrs). Forty-one (30%) reacted to muffin, 31 (23%) to pizza, 11 (8%) to rice pudding, 43 (32%) to unheated milk; 10 (7%) tolerated unheated milk. Only muffin and pizza reactors required treatment with epinephrine during the challenge; they also more frequently reported prior episodes of milk-induced anaphylaxis compared with other groups. There were no differences in additional clinical parameters. In children tolerating increasing doses of baked-milk, there was a trend for decreasing serum levels of specific cow milk-, casein-, and beta-lactoglobulin-IgE (P<0.0001), casein-IgG4 (P50.029), log ratio casein IgE/IgG4 (P<0.0001), casein-IgA (P50.02), and smaller skin prick test wheal diameters for milk extract, unheated and boiled milk (P<0.0001). There were no differences in peripheral blood T regulatory cells. CONCLUSIONS: Tolerance to increasing doses of less extensively heated milk in baked products is associated with gradually decreasing immunologic parameters and with lower rates of milk-induced anaphylaxis. Tolerance to extensively heated milk defines a milder phenotype of childhood milk allergy.
302
Efficacy & Safety of Abbreviated Oral Food Challenges in Ruling Out Food Allergy in a Pediatric Allergy Clinic Kelly M. Maples, MD1,2, Tyler Thompson1,3, Amy Perkins, MS1,2, Madison Smart, MA1; 1Children’s Hospital of The King’s Daughters, Norfolk, VA, 2Eastern Virginia Medical School, Norfolk, VA, 3Campbell University, Buies Creek, NC. RATIONALE: While the prevalence of food allergy (FA) is increasing, so is misdiagnosis. Indiscriminate use of allergy skin prick (SPT) and IgE testing can lead to false positive results and alone may not be sufficient. Traditional oral food challenges (OFC) are the gold standard for diagnosing FAs but are lengthy, costly, and often unpractical outside large academic centers. Abbreviated oral food challenges (AOFC) may offer physicians a safe and efficient diagnostic method for carefully selected patients. METHODS: A retrospective chart review of children ages 2 to 18 years old, who completed a two-step AOFC at our children’s hospital between January 2010 and March 2012, was performed to assess the safety of performing OFCs in an abbreviated fashion. AOFCs were completed in a 2-step method with a 15-minute interval. Patients’ charts were accessed to collect demographics, history, and challenge results. Sensitizations to allergens were confirmed by SPT and specific IgE testing. Descriptive statistics were calculated, and safety of AOFCs was assessed by the percentage of failed challenges that required epinephrine. RESULTS: 70 patients completed 99 AOFCs. 10 (10.1%) challenges were failed, and 2 patients required epinephrine. No patients required an additional dose of epinephrine. Sixty (85.7%) patients passed each challenge and were able to reintroduce previously avoided foods. CONCLUSIONS: The safety of AOFCs performed at our institution is comparable with published data on the safety of traditional multi-step OFCs. AOFCs are a safe, efficient, and effective diagnostic method to confirm FA in carefully selected patients and are more practical for the community allergist to perform.
SUNDAY
299
J ALLERGY CLIN IMMUNOL VOLUME 131, NUMBER 2
Basophil Allergen Threshold Sensitivity, CD-Sens, and IgE Antibodies to Wheat, Hydrolysed Wheat, v-5 Gliadin and Timothy Grass in Relation to Wheat Challenge Outcome Nora Nilsson; Astrid Lindgrens Childrens Hospital, Stockholm, Sweden. RATIONALE: Wheat is one of the six most common foods causing allergy, requires a wheat free diet and has implications on the quality of life. The diagnosis of IgE-mediated immediate wheat allergy is currently based on oral food challenges which are time consuming, associated with risks and not frequently performed. An improved diagnostic workup is needed for wheat allergy. METHODS: Twenty four children, aged 1-19 years, with a wheat allergy diagnosis underwent a open wheat challenge. CD-sens and IgE- antibodies to wheat, hydrolysed wheat protein (HWP), v-5 gliadin and timothy grass were analysed and related to the challenge outcome. RESULTS: Of the 24 patients 12 children had a positive challenge. IgEantibodies to wheat, v-5 gliadin and HWP but not timothy discriminated between positive and negative challenge to wheat. The children reacting in challenge had a significantly (p<0.001) higher IgE-antibody concentrations and a tendency (p50.075) to higher wheat CD-sens values than the non-reacting children. Almost all children sensitized to timothy had a positive CD-sens to timothy, even those with low concentrations of IgEantibodies to timothy. Seven out of nine challenge positive children had a positive CD-sens to HWP and they all had an IgE-ab concentration to HWP above 10 kUA/L. Five children had IgE-ab to HWP but were negative in CD-sens to HWP. CONCLUSIONS: IgE-antibodies to wheat components and CD-sens could be useful aids in diagnosing and follow-up of wheat allergic children particularly when oral challenges are difficult to perform.
300
Oral Food Challenge: Experience in a Brazilian Food Allergy Outpatient Terciary Service Camila Pereira1, Leila Borges2, Renata R. Cocco1, Lucila Camargo1, Marcia Mallozi1, Dirceu Sole, MD, PhD3; 1Federal University of S~ao Paulo, 2Federal University of Sao Paulo, 3Federal University of Sao Paulo, Sao Paulo, Brazil. RATIONALE: To evaluate the results of oral food challenges (OFC) performed on followed patients in the Food Allergy Outpatient Clinic of the Federal University of S~ao Paulo. METHODS: Retrospective analysis of patients9 records submitted to OFC. From 169 analyzed tests, 4 were excluded due to incomplete data. RESULTS: From June/2007 to June/2012, 165 OFC were performed with cow9s milk (108), egg 18, soy 13, tartrazine 11, peanut 3, wheat 2, coconut 2, cow meat 2, nuts 1, fish 1, chocolate 1, sausage 1, pineapple 1 and wine 1. Male gender was predominant (67,2%), and the mean age was 4,6 year-old. Challenges were positive in 24,2% (n540). The main observed symptoms were cutaneous (80%), nasal (25%), gastrintestinal (22,5%), laryngeal (12,5%) and pulmonary (10%). Anaphylaxis occurred in 7 patients (17,5%), with cow9s milk 4, egg 1, nuts 1 and coconut 1. Anti-histamin was used in 31 patients (77,5%), associated with oral steroid in 18 (45%), and only 3 patients required intramuscular adrenaline (7,5%). Other allergic diseases associated: rhinitis (47,5%), asthma (40%), atopic dermatitis (37,5%) and drug reaction (0,05%). Positive serum specific IgE and/or skin prick test to the suspected food was observed in 59,6% of the patients. CONCLUSIONS: Cow9s milk, egg and soy were the most suspected foods, and cutaneous symptoms were the most common observed reactions. Despite the suggestive food allergy history and presence of specific IgE, about half of the performed OFC resulted negative, reinforcing the importance of this test as the gold-standard method for food allergy diagnosis.
301
Tolerance to Extensively Heated (Baked) Milk-Clinical and Immunologic Phenotype Hugh A. Sampson, MD, FAAAAI1, George N. Konstantinou, MD, PhD, MSc1, Jacob Daniel Kattan, MD1, Madhan Masilamani, PhD1, Beth D. Strong, RN, CCRC2, Elizabeth Paynter, MA3, Tee Bahnson, BS, MPH3, Anna H. Nowak-Wegrzyn, MD, FAAAAI2; 1Mount Sinai School of Medicine, New York, NY, 2Mt. Sinai School of Medicine, New York, NY, 3Rho Federal Systems Division, Inc., Chapel Hill, NC. RATIONALE: We previously reported that 70% of cow milk-allergic children tolerate baked-milk products. We sought to further define clinical and immunologic phenotypes of tolerance to baked-milk METHODS: Children with suspected milk allergy were challenged sequentially over 2 days (up to 2 foods per day) to foods baked under different conditions and containing increasing amounts of milk. Antibody concentrations were measured with UniCAPÒ; T regulatory cells were measured by flow cytometry; skin prick tests were done with commercial extract, unheated milk and boiled-milk. RESULTS: 136 children (70% males) were enrolled (median age: 7 yrs; inter-quartile range, 5-9 yrs). Forty-one (30%) reacted to muffin, 31 (23%) to pizza, 11 (8%) to rice pudding, 43 (32%) to unheated milk; 10 (7%) tolerated unheated milk. Only muffin and pizza reactors required treatment with epinephrine during the challenge; they also more frequently reported prior episodes of milk-induced anaphylaxis compared with other groups. There were no differences in additional clinical parameters. In children tolerating increasing doses of baked-milk, there was a trend for decreasing serum levels of specific cow milk-, casein-, and beta-lactoglobulin-IgE (P<0.0001), casein-IgG4 (P50.029), log ratio casein IgE/IgG4 (P<0.0001), casein-IgA (P50.02), and smaller skin prick test wheal diameters for milk extract, unheated and boiled milk (P<0.0001). There were no differences in peripheral blood T regulatory cells. CONCLUSIONS: Tolerance to increasing doses of less extensively heated milk in baked products is associated with gradually decreasing immunologic parameters and with lower rates of milk-induced anaphylaxis. Tolerance to extensively heated milk defines a milder phenotype of childhood milk allergy.
302
Efficacy & Safety of Abbreviated Oral Food Challenges in Ruling Out Food Allergy in a Pediatric Allergy Clinic Kelly M. Maples, MD1,2, Tyler Thompson1,3, Amy Perkins, MS1,2, Madison Smart, MA1; 1Children’s Hospital of The King’s Daughters, Norfolk, VA, 2Eastern Virginia Medical School, Norfolk, VA, 3Campbell University, Buies Creek, NC. RATIONALE: While the prevalence of food allergy (FA) is increasing, so is misdiagnosis. Indiscriminate use of allergy skin prick (SPT) and IgE testing can lead to false positive results and alone may not be sufficient. Traditional oral food challenges (OFC) are the gold standard for diagnosing FAs but are lengthy, costly, and often unpractical outside large academic centers. Abbreviated oral food challenges (AOFC) may offer physicians a safe and efficient diagnostic method for carefully selected patients. METHODS: A retrospective chart review of children ages 2 to 18 years old, who completed a two-step AOFC at our children’s hospital between January 2010 and March 2012, was performed to assess the safety of performing OFCs in an abbreviated fashion. AOFCs were completed in a 2-step method with a 15-minute interval. Patients’ charts were accessed to collect demographics, history, and challenge results. Sensitizations to allergens were confirmed by SPT and specific IgE testing. Descriptive statistics were calculated, and safety of AOFCs was assessed by the percentage of failed challenges that required epinephrine. RESULTS: 70 patients completed 99 AOFCs. 10 (10.1%) challenges were failed, and 2 patients required epinephrine. No patients required an additional dose of epinephrine. Sixty (85.7%) patients passed each challenge and were able to reintroduce previously avoided foods. CONCLUSIONS: The safety of AOFCs performed at our institution is comparable with published data on the safety of traditional multi-step OFCs. AOFCs are a safe, efficient, and effective diagnostic method to confirm FA in carefully selected patients and are more practical for the community allergist to perform.
SUNDAY
299