- Email: [email protected]
The Relationship Between Self-Efficacy, Quality of Life, and Oral Food Challenge
Abstracts AB135
J ALLERGY CLIN IMMUNOL VOLUME 137, NUMBER 2
High Diagnostic Sensitivity and Specificity By Analysis of IgE to Different Types of Gliadins When Evaluating Wheat Allergy in Children
Sigrid Sjolander, PhD1, Nora Nilsson2, Helena Ekoff3, Sandra Wieser, PhD4, Gunilla Hedlin, MD, PhD5,6, Rudolf Valenta, MD4,7, Magnus P. Borres, MD, PhD, FAAAAI1,8, Caroline Nilsson, MD, PhD9; 1 Thermo Fisher Scientific, Uppsala, Sweden, 2Astrid Lindgrens Childrens Hospital, Stockholm, Sweden, 3Thermofisher Scientific, Uppsala, Sweden, 4Division of Immunopathology, Department of Pathophysiology and Allergy Research, Center of Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria, 5Karolinska Institutet, Stockholm, Sweden, 6Centre for Allergy Research, Karolinska Institutet, Stockholm, Sweden, 7Medical University of Vienna AKH, Wien, Austria, 8Department of Womens and Childrens Health, Uppsala University, Uppsala, Sweden, 9Department of Clinical Science and Education, S€ odersjukhuset, Karolinska Institutet and Sachs Childrens Hospital, S€ odersjukhuset, Stockholm, Sweden. RATIONALE: Wheat sensitization is more common than wheat allergy and as a result the specificity of the IgE antibody (IgE-ab) wheat test is poor. More specific tests, that correctly identify wheat allergic individuals, are needed. Allergens extracted from the gluten fraction of wheat, especially v5-gliadin, have proven useful in several recent studies. In this study we have evaluated the diagnostic performance of three different types of gliadins in a group of wheat allergic children. METHODS: Thirty-one children diagnosed with wheat allergy by either a positive oral wheat challenge or a convincing recent history, and 72 grasspollen allergic children currently eating wheat (controls) were recruited for the study. Sera were analyzed for IgE-ab to wheat, recombinant v5-gliadin, two recombinant g-gliadins and a native gliadin preparation containing a-, b-, g-, and v-gliadins using a cut-off of 0.35 kUA/l. RESULTS: The wheat test had a sensitivity of 100% but a lower specificity of 40%. Native gliadin had a similar sensitivity (94%) but better specificity (96%). Sensitivities were 81% for the two tests measuring IgE-ab to g-gliadin and 68% for the v5-gliadin test. Specificities for these tests ranged from 94 to 97%. CONCLUSIONS: Measurements of IgE-ab to gliadins are useful tools to support the identification of wheat food allergic children. All four gliadin tests evaluated had specificities of more than 94%. The test with native gliadins had the best sensitivity followed by the two g-gliadin tests and the v5-gliadin test.
447
The Relationship Between Self-Efficacy, Quality of Life, and Oral Food Challenge
Matthew J. Greenhawt, MD, MBA, MSc1, Christopher E. Couch, MD2, Timothy J. Franxman, MD3, Audrey Dunn Galvin4; 1Department of Internal Medicine, The University of Michigan Medical School, Division of Allergy and Clinical Immunology, Ann Arbor, MI, 2University of Michigan, Division of Allergy and Clinical Immunology, Ann Arbor, MI, 3University of Michigan, Ann Arbor, MI, 4University College Cork, Ireland. RATIONALE: Food allergy (FA) quality of life (QoL) has been shown to be better in caregivers of children undergoing OFC vs. non-challenged children. Self-efficacy (SE) describes one’s perceived capabilities for disease self-management, and is a powerful influence on coping, motivation and achievement. The relationship between SE, QoL, and OFC is unknown. METHODS: The Food Allergy Quality of Life Parental Burden (FAQLPB) index, Food Allergy Self-Efficacy Questionnaire (FASEQ), and a questionnaire assessing the individual’s food allergy history were administered to n5115 caregivers of peanut, tree nut, milk, and egg allergic children who underwent OFCs between 2001 and 2012 at a referral center, and n5305 unchallenged children. Questionnaire data were verified through chart review. RESULTS: Mean FASEQ score was higher (worse) in the challenged vs. non-challenged population (3.81 vs. 4, p50.02), but not significantly
different based on allergen, anaphylaxis, or age. Within the OFC group, no difference in FASEQ score was noted based on challenge outcome, allergen, presenting symptoms, or age. FASEQ score was negatively correlated with FAQL-PB score (r5-0.38, p<0.001). In an adjusted regression model, OFC and FASEQ were not associated. However, the addition of FASEQ score to a previous model demonstrating a significant relationship between OFC and better QoL strengthened this association, while explaining an additional 9% of the total variance in QoL (adj.R250.3) in the population. CONCLUSIONS: Caregiver SE is worse in challenged vs. nonchallenged populations but unaffected by OFC outcome or allergen. In adjusted models, OFC has no significant effect on SE, but SE significantly moderates the effect of OFC on QoL.
448
Fraction of Exhaled Nitric Oxide (FeNO) and Abdominal Pain and/or Vomiting in Reaction to Oral Food Challenge
Sara C. Slatkin, MD1, Dana Tupa2, Kari C. Nadeau, MD, PhD, FAAAAI3, R. Sharon Chinthrajah, MD3; 1Stanford Hospital and Clinics, Stanford, CA, 2Stanford University, Stanford, CA, 3Stanford. RATIONALE: FeNO is a surrogate marker of eosinophilic inflammation. Its clinical role in asthma is well established, as well as its relationship to peripheral, bronchial biopsy, sputum, and BAL eosinophilia. It has yet to be correlated with gastrointestinal eosinophilia and to be fully characterized in food allergy patients. We hypothesized that patients with elevated FeNO are more likely to have abdominal pain and/or vomiting with oral allergen challenge. METHODS: The Sean N. Parker Center for Allergy Research at Stanford screened 20 pediatric patients for an oral immunotherapy clinical trial and performed 80 FeNO measurements prior to double-blind placebocontrolled food challenges (DBPCFC). FeNO was obtained according to ATS guidelines, using Niox Mino. Exclusion criteria were: FEV1 less than 80% predicted, nitrate-rich food intake, or respiratory distress before or after challenge. RESULTS: FeNO, prior to DBPCFC, predicts abdominal pain and/or vomiting with a specificity of 82% at a cut-off of 60 ppb. Mean FeNO was 52 ppb in patients with abdominal pain and/or vomiting, compared to 41 without. There were no significant differences in gender, age, height, BMI, asthma, allergic rhinitis, atopic dermatitis, FEV1, use of inhaled corticosteroids, nasal steroids, or H2-blockers, and total IgE, as analyzed by Fisher’s exact and the two sample t-tests. CONCLUSIONS: Elevated FeNO was associated with abdominal pain and/or vomiting in DBPCFC, in this pediatric population with food allergies. This result, if confirmed in a larger cohort, will allow use of a non-invasive test for the prediction of GI responses to oral allergen challenge.
SUNDAY
446
J ALLERGY CLIN IMMUNOL VOLUME 137, NUMBER 2
High Diagnostic Sensitivity and Specificity By Analysis of IgE to Different Types of Gliadins When Evaluating Wheat Allergy in Children
Sigrid Sjolander, PhD1, Nora Nilsson2, Helena Ekoff3, Sandra Wieser, PhD4, Gunilla Hedlin, MD, PhD5,6, Rudolf Valenta, MD4,7, Magnus P. Borres, MD, PhD, FAAAAI1,8, Caroline Nilsson, MD, PhD9; 1 Thermo Fisher Scientific, Uppsala, Sweden, 2Astrid Lindgrens Childrens Hospital, Stockholm, Sweden, 3Thermofisher Scientific, Uppsala, Sweden, 4Division of Immunopathology, Department of Pathophysiology and Allergy Research, Center of Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria, 5Karolinska Institutet, Stockholm, Sweden, 6Centre for Allergy Research, Karolinska Institutet, Stockholm, Sweden, 7Medical University of Vienna AKH, Wien, Austria, 8Department of Womens and Childrens Health, Uppsala University, Uppsala, Sweden, 9Department of Clinical Science and Education, S€ odersjukhuset, Karolinska Institutet and Sachs Childrens Hospital, S€ odersjukhuset, Stockholm, Sweden. RATIONALE: Wheat sensitization is more common than wheat allergy and as a result the specificity of the IgE antibody (IgE-ab) wheat test is poor. More specific tests, that correctly identify wheat allergic individuals, are needed. Allergens extracted from the gluten fraction of wheat, especially v5-gliadin, have proven useful in several recent studies. In this study we have evaluated the diagnostic performance of three different types of gliadins in a group of wheat allergic children. METHODS: Thirty-one children diagnosed with wheat allergy by either a positive oral wheat challenge or a convincing recent history, and 72 grasspollen allergic children currently eating wheat (controls) were recruited for the study. Sera were analyzed for IgE-ab to wheat, recombinant v5-gliadin, two recombinant g-gliadins and a native gliadin preparation containing a-, b-, g-, and v-gliadins using a cut-off of 0.35 kUA/l. RESULTS: The wheat test had a sensitivity of 100% but a lower specificity of 40%. Native gliadin had a similar sensitivity (94%) but better specificity (96%). Sensitivities were 81% for the two tests measuring IgE-ab to g-gliadin and 68% for the v5-gliadin test. Specificities for these tests ranged from 94 to 97%. CONCLUSIONS: Measurements of IgE-ab to gliadins are useful tools to support the identification of wheat food allergic children. All four gliadin tests evaluated had specificities of more than 94%. The test with native gliadins had the best sensitivity followed by the two g-gliadin tests and the v5-gliadin test.
447
The Relationship Between Self-Efficacy, Quality of Life, and Oral Food Challenge
Matthew J. Greenhawt, MD, MBA, MSc1, Christopher E. Couch, MD2, Timothy J. Franxman, MD3, Audrey Dunn Galvin4; 1Department of Internal Medicine, The University of Michigan Medical School, Division of Allergy and Clinical Immunology, Ann Arbor, MI, 2University of Michigan, Division of Allergy and Clinical Immunology, Ann Arbor, MI, 3University of Michigan, Ann Arbor, MI, 4University College Cork, Ireland. RATIONALE: Food allergy (FA) quality of life (QoL) has been shown to be better in caregivers of children undergoing OFC vs. non-challenged children. Self-efficacy (SE) describes one’s perceived capabilities for disease self-management, and is a powerful influence on coping, motivation and achievement. The relationship between SE, QoL, and OFC is unknown. METHODS: The Food Allergy Quality of Life Parental Burden (FAQLPB) index, Food Allergy Self-Efficacy Questionnaire (FASEQ), and a questionnaire assessing the individual’s food allergy history were administered to n5115 caregivers of peanut, tree nut, milk, and egg allergic children who underwent OFCs between 2001 and 2012 at a referral center, and n5305 unchallenged children. Questionnaire data were verified through chart review. RESULTS: Mean FASEQ score was higher (worse) in the challenged vs. non-challenged population (3.81 vs. 4, p50.02), but not significantly
different based on allergen, anaphylaxis, or age. Within the OFC group, no difference in FASEQ score was noted based on challenge outcome, allergen, presenting symptoms, or age. FASEQ score was negatively correlated with FAQL-PB score (r5-0.38, p<0.001). In an adjusted regression model, OFC and FASEQ were not associated. However, the addition of FASEQ score to a previous model demonstrating a significant relationship between OFC and better QoL strengthened this association, while explaining an additional 9% of the total variance in QoL (adj.R250.3) in the population. CONCLUSIONS: Caregiver SE is worse in challenged vs. nonchallenged populations but unaffected by OFC outcome or allergen. In adjusted models, OFC has no significant effect on SE, but SE significantly moderates the effect of OFC on QoL.
448
Fraction of Exhaled Nitric Oxide (FeNO) and Abdominal Pain and/or Vomiting in Reaction to Oral Food Challenge
Sara C. Slatkin, MD1, Dana Tupa2, Kari C. Nadeau, MD, PhD, FAAAAI3, R. Sharon Chinthrajah, MD3; 1Stanford Hospital and Clinics, Stanford, CA, 2Stanford University, Stanford, CA, 3Stanford. RATIONALE: FeNO is a surrogate marker of eosinophilic inflammation. Its clinical role in asthma is well established, as well as its relationship to peripheral, bronchial biopsy, sputum, and BAL eosinophilia. It has yet to be correlated with gastrointestinal eosinophilia and to be fully characterized in food allergy patients. We hypothesized that patients with elevated FeNO are more likely to have abdominal pain and/or vomiting with oral allergen challenge. METHODS: The Sean N. Parker Center for Allergy Research at Stanford screened 20 pediatric patients for an oral immunotherapy clinical trial and performed 80 FeNO measurements prior to double-blind placebocontrolled food challenges (DBPCFC). FeNO was obtained according to ATS guidelines, using Niox Mino. Exclusion criteria were: FEV1 less than 80% predicted, nitrate-rich food intake, or respiratory distress before or after challenge. RESULTS: FeNO, prior to DBPCFC, predicts abdominal pain and/or vomiting with a specificity of 82% at a cut-off of 60 ppb. Mean FeNO was 52 ppb in patients with abdominal pain and/or vomiting, compared to 41 without. There were no significant differences in gender, age, height, BMI, asthma, allergic rhinitis, atopic dermatitis, FEV1, use of inhaled corticosteroids, nasal steroids, or H2-blockers, and total IgE, as analyzed by Fisher’s exact and the two sample t-tests. CONCLUSIONS: Elevated FeNO was associated with abdominal pain and/or vomiting in DBPCFC, in this pediatric population with food allergies. This result, if confirmed in a larger cohort, will allow use of a non-invasive test for the prediction of GI responses to oral allergen challenge.
SUNDAY
446