Objective: To assess the association between atopic dermatitis (AD) and ascariasis in 2 to 10-aged children from the neighborhood Pedregal, in the city of Campina Grande, Brazil, an area of low socioeconomic index.
Methods: Cross-sectional study conducted with the use of the standard questionnaire from the International Study of Asthma and Allergies in Childhood (ISAAC) and stool parasitological exam for Ascaris lumbricoides. The dependent variable was AD diagnosis: absent, mild, and severe. Multivariate logistic regression and descriptive analysis of the variable were used. Associations were estimated using relative risk (RR) and odds ratio (OR). The statistical inference was based on 95% confidence intervals (95%CI).
Results: We assessed 1,195 children, 612 (51.2%) female. The AD prevalence was 24.6%, and ascariasis prevalence was 26.1%. In the mild AD group of children, 44 (36.7%) were infected by A. lumbricoides while in the severe AD group, 40 (22.9%) had the same geohelminthosis (p = 0.01). Comparing negative cases of AD between mild and severe forms, the infection with A. lumbricoides increased the frequency of mild AD (RR = 1.7; p = 0.009), but not the severe form (RR = 0.86; p = 0.46). Evaluating only the positive cases of dermatitis, 120 mild AD (40.8%) and 176 with severe AD (58.2%), it can be said that the exposure to the parasite decreased the frequency of the severe form of dermatitis (RR = 1.46; p = 0.016).
Conclusion: There is a high prevalence of AD and of ascariasis in the population studied. The severe AD is related to lower parasitemia of A. lumbricoides.