Prevention of occupational rhinitis and asthma in sensitized workers exposed to laboratory animals

Abstract

Background: In this work we propose to evaluate the effect of probiotics on the onset of asthma and rhinitis due to contact with laboratory animals. This will be a pioneering study on probiotics in atopic adults. Potentially, probiotics can become a preventive treatment for asthma, with reduced cost and no side effects. Objective: To know the effect of probiotics on the development of asthma and rhinitis in sensitized workers exposed to laboratory animals. Methods: This is a randomized, controlled study with students and workers who have exposure to laboratory animals and who have a positive allergic skin test to at least one of these animals: rat, mouse, hamster, guinea pig or rabbit. Recruitment and study will take place at university with volunteers who do not have asthma or rhinitis defined by symptoms. These volunteers will be divided into 2 groups, treatment group (n = 100) and control group (n = 100), both will be followed for 2 years. The treatment group will receive a daily capsule containing 3 strains of probiotics, 10 (to the nineth) colony forming units (CFU) of Lactobacillus rhamnosus HN001, Lactobacillus paracasei Lpc-37 and Bifidobacterium animalis ssp lactis HN019. The control group will receive a placebo capsule. The intervention and control groups will be followed up for 2 years and will be evaluated by questionnaires, spirometry, bronchial challenge test with methacholine for confirmation of asthma, immediate hypersensitivity skin test for common allergens and for specific allergens (animals of interest), blood count, measurement of total and specific IgE to these animals, parasitological stool and PCR (faeces) to identify colonization by these strains of probiotics. Data analysis: The groups will be compared by means of the chi-square test for categorical variables, for example, asthma prevalence and by the unpaired Student t test for continuous variables, for example, spirometric values. These same comparisons will be made at the beginning of the study to assess homogeneity between groups.