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A New Model for Anxiety-Avoidance Behaviour in Food Allergy: Cognitive-Emotional Sensitisation in Children
S254 Abstracts
981
Food Allergy Education for Pediatric Dietitians: A Needs Assessment Survey M. Groetch1, L. Christie2, P. Vargas2, S. Mofidi1, S. Jones2, S. H. Sicherer1; 1Mt. Sinai School of Medicine, New York, NY, 2Arkansas Children’s Hospital, Little Rock, AR. RATIONALE: Pediatric dietitians are increasingly needed to manage children with food allergies (FA); we sought to determine their educational preferences. METHODS: An internet-based, anonymous survey distributed by email to the Pediatric Nutrition Practice Group of the American Dietetic Association. RESULTS: Respondents (n 5 311, 50% with >15 years experience) worked primarily in ambulatory (41%) and inpatient (38%) settings. The estimated percent of clients comprised of children with FA was: None (10%), <10% (48%), 10-49% (35%) and 50-100% (7%). On a four point scale of proficiency (High-Mod-Low-None), respondents primarily rated themselves ‘‘moderate’’ for educating families, creating diets, and evaluating safe foods, and ‘‘low’’ for creating diagnostic food challenges. Education had been primarily self-taught (75%), through the Food Allergy & Anaphylaxis Network (59%) and continuing education (52%). Primary sources to update knowledge were: professional publications (85%), materials from advocacy groups (72%) and academic websites (59%). Dietitians primarily educated clients using handouts (92%) and individual teaching (76%). Preferences for future resources included handbooks (77%) and web-based instructional programs (53%); for patient materials, handouts were preferred (89%). Among various modalities to obtain resources, internet access was preferred. On a 4 point scale (‘‘very’’ to ‘‘not at all’’) among practices that included >10% patients with FA, ratings of ‘‘very’’ were selected as follows: need resources to update FA knowledge87%; need for a food allergy ‘‘tool kit’’-84%. CONCLUSIONS: Dietitians generally rate their current proficiency in caring for children with FA as ‘‘moderate’’ and would prefer and likely benefit from internet accessible management handbooks and patient handouts. Funding: NIH-NIAID (U19AI066738) Consortium of Food Allergy Research
982
TUESDAY
Cow's Milk Allergy. Results of Hyposensitization in 13 Children G. B. Pajno, G. Barberio, D. Vita, L. Caminiti; Istituto Clinica PediatricaPoliclinico Universitario-Messina-ITALY, Messina, ITALY. RATIONALE: Cow Milk (CM) allergy usually disappears or attenuates after 3 years of age, but in some cases it persists, with severe or life threatening symptoms and therefore a hyposenstization may be indicated. METHODS: The protocol lasted 180 days with 2 drops of CM diluted 1:25 and progressively increasing until 200 mL of undiluted milk. We treated 13 children (6 male, mean age 6,4 years, range 4 -10 years), among them 6 patients carried out a double blind placebo controlled study. The placebo part of the challenge was soy formula. RESULTS: All children had positive skin tests, CAP-Rast and DBPCFC to CM. Seven patients were treated with open desensitization protocol. Four children had completed the protocol. In the remaining three children the desensitization had to be interrupted, in two at 2 mL and in one at 64 mL of milk because of generalized urticaria, angioedema, rhinitis and asthma. Among children treated with placebo (soy formula) or CM, three tolerated the placebo but showed again symptoms after a repeat ingestion of CM. Two children who received CM had completed the protocol, one child had interrupted the challenge at the dose of 4 mL because of urticaria and wheezing. CONCLUSIONS: Hyposensitization to CM may be fully effective in some children, however other had interrupted the challenge during CM desensitization owing to the appearance of severe adverse events. The placebo part of the challenge was, as expected, ineffective. Funding: University of Messina - ITALY
J ALLERGY CLIN IMMUNOL FEBRUARY 2008
983
A New Model for Anxiety-Avoidance Behaviour in Food Allergy: Cognitive-Emotional Sensitisation in Children A. DunnGalvin, J. O. B. Hourihane; University College Cork, Cork, IRELAND. RATIONALE: Allergists assume, but have never confirmed, that high levels of vigilance in children performs an adaptive protective function. Cognitive emotional sensitisation is a feed forward mechanism where attention is increasingly focussed on processing of fear-related information. METHOD: To ensure comprehensiveness, we used grounded theory to analyse data from10 focus groups with 36 allergic children aged 6 to 12 years. In addition, 36 mothers completed the FAQLQ-PF, a developmentally appropriate quality of life measure for food allergic children with 3 sub-scales; general emotional impact (GEI), food anxiety (FAx), social & dietary restrictions SDR). RESULTS: Maternal (1) and child (2) reports were analogous. (1) We found a strong relationship between maternal report on items concerning general anxiety and items relating to both FAx and SDR (0.823; 0.749 p < .001). A high score on GEI was a strong predictor of parental assessment of total impact on children’s quality of life (OR 5.8;1.5-7.6). Effects were unrelated to time since anaphylaxis (Chi2 5 2.4, p 5 0.25). (2) Uncertainty plays a central role in the modulation of information processing. Restrictions lead to generalised perception of threat. General social anxiety and avoidance, unrelated to actual level of risk, increases with age (6-8 yrs 30% vs. 9-12 yrs 45%). CONCLUSION: Anxiety induced by food allergy is long lasting and pervades all aspects of a child’s development. Cognitive emotional sensitisation explains how initial efforts to adapt to threat of food allergen exposure under conditions of uncertainty, amplified by constant vigilance and restrictions in lifestyle, lead to generalised anxiety avoidance behaviour in food allergic children. Funding: EuroPrevall (EU)
984
Allergen-specific Immunotherapy in Peanut-sensitized C3H/ HeJ Mice Induces Protection More Relevant to Treg Function Than Treg Number Y. Li1, L. Pons1, M. Kulis2, A. W. Burks2; 1Department of Pediatric Allergy and Immunology, Duke University Medical Center, Durham, NC, 2Department of Pediatrics Allergy and Immunology, Duke University Medical Center, Durham, NC. RATIONALE: Regulatory T cells (Tregs) play a key role for peripheral tolerance and the prevention of allergy. Peanut-specific IgG1 and IgE were increased in desensitized mice compared to sensitized mice indicating that protection was conferred at the T cell level, which promoted us to investigate the difference in Tregs. METHODS: Using Foxp3 as a specific marker, Treg numbers were measured in splenocytes and lymph node cells isolated from naı¨ve, peanutsensitized and desensitized mice. Treg proliferation was measured by CFSE dilution assay. Treg suppressive function was assessed in a co-culture proliferation assay with splenocytes from peanut-sensitized mice. RESULTS: Compared to naı¨ve mice, the percentage of Tregs from sensitized and desensitized mice was increased 50% and 30% in lymph node cells, 13% and 32% in splenocytes, respectively. After 3-day stimulation with peanut proteins, approximately 1% Foxp31 cells proliferated in CD41 T cells from both sensitized and desensitized splenocytes. However, there are no differences in Tregs percentage in CD41 cells. Co-culture experiments demonstrated that only Tregs from naı¨ve and desensitized mice inhibited proliferation of splenocytes derived from peanut-sensitized mice. No inhibition was induced by Tregs isolated from sensitized mice. CONCLUSION: A small proportion of Tregs from peanut sensitized and desensitized mice was not anergic and proliferated after peanut stimulation. Rather than their intrinsic numbers, it is the ability of Tregs to suppress effector T cells that contributes to the protection offered by allergen-specific desensitization. Funding: Duke University
981
Food Allergy Education for Pediatric Dietitians: A Needs Assessment Survey M. Groetch1, L. Christie2, P. Vargas2, S. Mofidi1, S. Jones2, S. H. Sicherer1; 1Mt. Sinai School of Medicine, New York, NY, 2Arkansas Children’s Hospital, Little Rock, AR. RATIONALE: Pediatric dietitians are increasingly needed to manage children with food allergies (FA); we sought to determine their educational preferences. METHODS: An internet-based, anonymous survey distributed by email to the Pediatric Nutrition Practice Group of the American Dietetic Association. RESULTS: Respondents (n 5 311, 50% with >15 years experience) worked primarily in ambulatory (41%) and inpatient (38%) settings. The estimated percent of clients comprised of children with FA was: None (10%), <10% (48%), 10-49% (35%) and 50-100% (7%). On a four point scale of proficiency (High-Mod-Low-None), respondents primarily rated themselves ‘‘moderate’’ for educating families, creating diets, and evaluating safe foods, and ‘‘low’’ for creating diagnostic food challenges. Education had been primarily self-taught (75%), through the Food Allergy & Anaphylaxis Network (59%) and continuing education (52%). Primary sources to update knowledge were: professional publications (85%), materials from advocacy groups (72%) and academic websites (59%). Dietitians primarily educated clients using handouts (92%) and individual teaching (76%). Preferences for future resources included handbooks (77%) and web-based instructional programs (53%); for patient materials, handouts were preferred (89%). Among various modalities to obtain resources, internet access was preferred. On a 4 point scale (‘‘very’’ to ‘‘not at all’’) among practices that included >10% patients with FA, ratings of ‘‘very’’ were selected as follows: need resources to update FA knowledge87%; need for a food allergy ‘‘tool kit’’-84%. CONCLUSIONS: Dietitians generally rate their current proficiency in caring for children with FA as ‘‘moderate’’ and would prefer and likely benefit from internet accessible management handbooks and patient handouts. Funding: NIH-NIAID (U19AI066738) Consortium of Food Allergy Research
982
TUESDAY
Cow's Milk Allergy. Results of Hyposensitization in 13 Children G. B. Pajno, G. Barberio, D. Vita, L. Caminiti; Istituto Clinica PediatricaPoliclinico Universitario-Messina-ITALY, Messina, ITALY. RATIONALE: Cow Milk (CM) allergy usually disappears or attenuates after 3 years of age, but in some cases it persists, with severe or life threatening symptoms and therefore a hyposenstization may be indicated. METHODS: The protocol lasted 180 days with 2 drops of CM diluted 1:25 and progressively increasing until 200 mL of undiluted milk. We treated 13 children (6 male, mean age 6,4 years, range 4 -10 years), among them 6 patients carried out a double blind placebo controlled study. The placebo part of the challenge was soy formula. RESULTS: All children had positive skin tests, CAP-Rast and DBPCFC to CM. Seven patients were treated with open desensitization protocol. Four children had completed the protocol. In the remaining three children the desensitization had to be interrupted, in two at 2 mL and in one at 64 mL of milk because of generalized urticaria, angioedema, rhinitis and asthma. Among children treated with placebo (soy formula) or CM, three tolerated the placebo but showed again symptoms after a repeat ingestion of CM. Two children who received CM had completed the protocol, one child had interrupted the challenge at the dose of 4 mL because of urticaria and wheezing. CONCLUSIONS: Hyposensitization to CM may be fully effective in some children, however other had interrupted the challenge during CM desensitization owing to the appearance of severe adverse events. The placebo part of the challenge was, as expected, ineffective. Funding: University of Messina - ITALY
J ALLERGY CLIN IMMUNOL FEBRUARY 2008
983
A New Model for Anxiety-Avoidance Behaviour in Food Allergy: Cognitive-Emotional Sensitisation in Children A. DunnGalvin, J. O. B. Hourihane; University College Cork, Cork, IRELAND. RATIONALE: Allergists assume, but have never confirmed, that high levels of vigilance in children performs an adaptive protective function. Cognitive emotional sensitisation is a feed forward mechanism where attention is increasingly focussed on processing of fear-related information. METHOD: To ensure comprehensiveness, we used grounded theory to analyse data from10 focus groups with 36 allergic children aged 6 to 12 years. In addition, 36 mothers completed the FAQLQ-PF, a developmentally appropriate quality of life measure for food allergic children with 3 sub-scales; general emotional impact (GEI), food anxiety (FAx), social & dietary restrictions SDR). RESULTS: Maternal (1) and child (2) reports were analogous. (1) We found a strong relationship between maternal report on items concerning general anxiety and items relating to both FAx and SDR (0.823; 0.749 p < .001). A high score on GEI was a strong predictor of parental assessment of total impact on children’s quality of life (OR 5.8;1.5-7.6). Effects were unrelated to time since anaphylaxis (Chi2 5 2.4, p 5 0.25). (2) Uncertainty plays a central role in the modulation of information processing. Restrictions lead to generalised perception of threat. General social anxiety and avoidance, unrelated to actual level of risk, increases with age (6-8 yrs 30% vs. 9-12 yrs 45%). CONCLUSION: Anxiety induced by food allergy is long lasting and pervades all aspects of a child’s development. Cognitive emotional sensitisation explains how initial efforts to adapt to threat of food allergen exposure under conditions of uncertainty, amplified by constant vigilance and restrictions in lifestyle, lead to generalised anxiety avoidance behaviour in food allergic children. Funding: EuroPrevall (EU)
984
Allergen-specific Immunotherapy in Peanut-sensitized C3H/ HeJ Mice Induces Protection More Relevant to Treg Function Than Treg Number Y. Li1, L. Pons1, M. Kulis2, A. W. Burks2; 1Department of Pediatric Allergy and Immunology, Duke University Medical Center, Durham, NC, 2Department of Pediatrics Allergy and Immunology, Duke University Medical Center, Durham, NC. RATIONALE: Regulatory T cells (Tregs) play a key role for peripheral tolerance and the prevention of allergy. Peanut-specific IgG1 and IgE were increased in desensitized mice compared to sensitized mice indicating that protection was conferred at the T cell level, which promoted us to investigate the difference in Tregs. METHODS: Using Foxp3 as a specific marker, Treg numbers were measured in splenocytes and lymph node cells isolated from naı¨ve, peanutsensitized and desensitized mice. Treg proliferation was measured by CFSE dilution assay. Treg suppressive function was assessed in a co-culture proliferation assay with splenocytes from peanut-sensitized mice. RESULTS: Compared to naı¨ve mice, the percentage of Tregs from sensitized and desensitized mice was increased 50% and 30% in lymph node cells, 13% and 32% in splenocytes, respectively. After 3-day stimulation with peanut proteins, approximately 1% Foxp31 cells proliferated in CD41 T cells from both sensitized and desensitized splenocytes. However, there are no differences in Tregs percentage in CD41 cells. Co-culture experiments demonstrated that only Tregs from naı¨ve and desensitized mice inhibited proliferation of splenocytes derived from peanut-sensitized mice. No inhibition was induced by Tregs isolated from sensitized mice. CONCLUSION: A small proportion of Tregs from peanut sensitized and desensitized mice was not anergic and proliferated after peanut stimulation. Rather than their intrinsic numbers, it is the ability of Tregs to suppress effector T cells that contributes to the protection offered by allergen-specific desensitization. Funding: Duke University