223 Patterns of Skin Prick Test Positivity in 519 Patients with Allergic Rhinitis and Asthma in Mexico City

BACKGROUND: There are studies in Mexico and worldwide about the patterns of positivity of skin prick test and the most frecuently allergens were: Dermatophagoides pteronyssinus (DPT), tree pollens (Ash/Oak in Mexico, Oak in U.S.A, Birch in Europe), grasses (Bermuda in Mexico, Timothy in U.S.A and Lolium in Europe) and thirdly cat ephitelium(CE). The reactivity to allergens was more common in males and the age groups in which there were positive skin test with the highest prevalence was from 5 to 15 years and 21 to 40 years. METHODS: The objective is to determine the pattern of skin prick test reactivity to aeroallergens in patients with rhinitis and asthma allergic in Mexico city, attending in the National Institute of Respiratory Disease (INER). This is a prospective, observational and longitudinal study based on data analysis of skin prick test results of individuals with clinical diagnosis of airway allergy (rhinitis/asthma). We use standardized allergens (alkalbello), detailed clinic history was collected in all cases. The statistical analysis was performed with the program SPSS14. RESULTS: We obtained a total of 519 patients with positive skin prick test between January 2009 and March 2011. This group comprised 47% females and 53% male, with a mean age of 19 years between 3 to 79 years. We have 253patients with allergic rhinitis (AR) and asthma (A), 173 with RA and 93 with A. 55% of the patients reacted to one allergen extract (AE) and 45% of the patients reacted with 2 or more AE. The most frequently indoor allergenswith positive skin prick test were Dpt (65.1%), Dermatophagoides farinae (Df) in 32.3%, CE(31.7%), Cockroach (11.5%). Among the outdoor allergens ash was positive in 23.3%, Ligustrum (18.8%) oak (17.7%) birch (13.6%) Western Juniperus (9.6%), Ulm (8.6%). CONCLUSIONS: The most frequently positivity skin prick test were Dpt, Df, CE, Ash, Privet, Oak. The reactivity to allergens was more common in males, and there are 3 peaks of age of positivity on prick test (7–12 years, 25–29 years and 36 years).