Southeast Distrito Federal 9.9% (95% CI, 8.5-11.3%), Toluca 5.9% (95% CI, 5.1-6.7%), Tijuana 8.2% (95% CI, 7.2-9.2%), Veracruz 9.7% (95% CI, 8.4-10.9%).Identified risk factors for the presence of wheezing in the last 12 months were: nasal symptoms accompanied with ocular symptoms (itching and tearing) in the last 12 months, OR 2.31 (95% CI, 2.01-2.66; P # 0.0001). Nasal symptoms (blocked nose, runny nose, and/or itching) in the last 12 months, OR 2.2 (95% CI, 1.66-2.92; P # 0.0001). Hay fever diagnosis by medical staff OR 2.02 (95% CI, 1.72-2.37; P # 0.0001). Atopic dermatitis symptoms (classic morphology and distribution) in the last 12 months, OR 1.65 (95% CI, 1.39-1.96; P # 0.0001). Use of anti- biotics in the first 12 months of life, OR 1.68 (95% CI, 1.48-1.90; P # 0.0001). Use of acetaminophen in the last 12 months, OR 1.49 (95% CI, 1.35-1.65; P # 0.0001). Conclusions: The presence of allergic rhinoconjuntivitis symptoms in the last 12 months doubles the risk for the presence of wheezing in Mexican children. 53 Association Between Eosinophil Apoptosis in Induced Sputum and Asthma Severity in Children Alla Nakonechna, MD, PhD, 1 Yuriy Antipkin, 2 Tatiana Umanets, MD, PhD, 2 Vladimir Lapshyn, 2 and Tamara Zadorozhnaja, MD 2 . 1 Allergy, Royal Liverpool and Broadgreen University Hospitals NHS Trust, Neston, United Kingdom; 2 Institute of Paediatrics, Obstetrics and Gynaecology, Kiev, Ukraine. Background: There is increasing evidence that the disorder of eosinophil apoptosis contributes to the mechanism of prominent airway inflammation in asthma. However the relationship between dysregulation of eosinophil apoptosis and severity of childhood asthma is still unclear. Objective: Investigate the relationship between eosinophil apoptosis in induced sputum and severity of asthma in children. Methods: Eighty-six children aged 6 to 12 years with asthma and 32 age- matched healthy controls were observed. Diagnosis of asthma was made using a clinical questionnaire, physical examination and skin prick tests (SPTs). Lung function, and induced sputum analysis were measured in all patients. Total and antigen specific IgE levels were assessesed by ELISA. Eosonophils apoptosis was determined by staining nuclei with propidium iodide, and analyzed with a FACScan. Expression Apo-1/Fas antigen (CD95) in sputum eosinophils was assessed by immunohistochemical staining techniques. Results: Diagnosis of asthma was confirmed by positive SPT and increased total and specific IgE levels. Asthma severity (assessed by FEV1, peak expiratory flow (PEF) variability and daily symptom scores) complied with mild and moderate asthma. The percentage sputum eosinophils was expressively increased (threshold of ,3%) in all asth- matic children (compared to control group) and directly correlated with peripheral blood eosinophilia, skin sensitization, increased level of total and specific IgE and clinical symptoms of asthma and all of these markers were more significant in children with moderate asthma (P , 0.05). Asthma children showed decreased eosinophils apoptosis (“apoptotic ra- tio”-AR) in induced sputum as compared to controls (P , 0.001), which directly correlated with predicted value of FEV1, PEF variability and in- versely with symptoms score (P ¼ 0.005), and was significantly lower in patients with moderate asthma than those in patients with mild (P ¼ 0.001). More of that, these parameters also correlated with decreased expression of Apo-1/Fas antigen (CD95), especially in moderate asthmatic children (P , 0.05). Conclusions: Our investigation: 1. Confirms that reduced eosinophil apoptosis in induced sputum associated with increased clinical severity of asthma in children. 2. Provides additional evidence that eosinophil apoptosis may be important in the resolution of eosinophilic airway inflammation in asthma, because of their prolonged survival that maintains inflammation. 54 Antibiotics but not Paracetamol Reduce the Risk for Recurrent Wheezing in Infants Herberto Jose Chong Neto, MD, PhD, Nelson Rosario, MD, PhD, Flávia Carnieli Silva, Lylia Fátima Melniski Bojarski, Emanuel Antonio Grasselli, Cristine Secco Rosario, Bernardo Augusto Rosario, and Fernando Henrique Chong. Allergy and Immunology, Federal University of Paraná, Curitiba, Brazil. Background: Paracetamol (PCM) and antibiotic (ATB) use have been associated with risk for wheezing and asthma in children. The aim of this study was to verify the association of recurrent wheezing ($3 episodes) in infancy and use of ATB or PCM in the first year of life. Methods: Cross-sectional study using a standardized and validated question- naire (EISL: Estudio Internacional sobre Sibilancias en Lactantes) with ques- tions: Has your baby had wheezing or whistling in the chest area or bronchitis in the first 12 months of life? Has your baby had 3 or more wheezing episodes in the first year of life? How often has your baby used antibiotics in the first year of life? How often has your baby used paracetamol in the first year of life? Parents of infants, ages 12 to 15 months that attended to Health Centers for routine immunization were interviewed between September 2009 to September 2010 (EISL Phase III). Risk was demonstrated using Odds ratio and 95% CI. Results: One thousand and 3 parents participated in the survey and 19.8% of infants had recurrent wheezing starting at 6.1 6 3 months. The use of PCM was not related to the presence of recurrent wheezing [No PCM (OR ¼ 0.91; 95% CI, 0.38-2.19; P ¼ 0.83), PCM 1–3 times (OR ¼ 1.21; 95% CI, 0.77-1.91; P ¼ 0.4), PCM 4–6 times (OR ¼ 1.21; 95% CI, 0.77-1.9; P ¼ 0.41) and PCM $7 times (OR ¼ 0.76; 95% CI, 0.51-1.13; P ¼ 0.17)], while more frequent use of ATB reduced the risk of recurrent wheezing in the first year of life [No ATB (OR ¼ 2.18; 95% CI, 1.35-3.51; P ¼ 0.001), ATB 1–3 times (OR ¼ 1.39; 95% CI, 0.93-2.07; P ¼ 0.1), ATB 4–6 times (OR ¼ 0.37; 95% CI, 0.22-0.62; P ¼ 0.001) and PCM$7 times (OR ¼ 0.22; 95% CI, 0.07-0.66; P ¼ 0.001)]. Conclusions: The frequent use of ATB reduced the risk of recurrent wheezing in the first year of life unlike PCM that was not associated with recurrent wheezing in this study population. CONJUNCTIVITIS 55 Ocular Signs and Symptoms Elicited by a Naturalistic Allergen Challenge in an Environmental Exposure Chamber Model Versus a Direct Allergen Instillation Model Michael S. Blaiss, MD, 1 Maria J. Tort, 2 Richard Ornberg, 2 Bruno Lay, 3 Fiona Soong, 4 and Anne Marie Salapatek 4 . 1 Allergy and Asthma Care, Germantown, TN; 2 Alcon Research Ltd, Fort Worth, TX; 3 ADCIS, Hérouville Saint-Clair, France; 4 Cetero Research, Mississauga, ON, Canada. Background: Direct-instillation ocular models are well established for eliciting allergic responses in research and clinical testing. This study compared direct ocular instillation of allergen to a more naturalistic airborne allergen exposure. Methods: Thirteen subjects with histories of ragweed allergy and positive skin prick responses attended screening, dose-finding, dose‑confirmation, and analysis study visits. For conjunctival allergen provocation testing (CAPT), 1 drop of ragweed allergen was administered to each eye, at the lowest possible subject-specific concentration between 1.6 and 100 protein nitrogen units per 25 ml drop. For environmental exposure chamber (EEC) testing, subjects were exposed to continual airborne ragweed pollen at 3500 6 500 par- ticles/m 3 . Symptoms of itching and tearing were self-assessed on diary cards by subjects. Signs of hyperemia, swelling, and mucous discharge were assessed by clinicians. Assessment time points started at 30 minutes before exposure and continued through 180 minutes after exposure. WAO Journal  February 2012 Abstracts Ó 2012 World Allergy Organization S35 Copyright @ World Allergy Organization. Unauthorized reproduction of this article is prohibited. 2012