Atopic dermatitis and ascariasis in children aged 2 to 10 years

Abstract

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. J Pediatr (Rio J). 2010;86(1):53-58: Atopic dermatitis, ascariasis, prevalence, children. ResumoObjetivo: Avaliar a associação entre dermatite atópica (DA) e ascaridíase em crianças de 2 a 10 anos do bairro do Pedregal, Campina Grande (PB), área de baixos indicadores socioeconômicos.Métodos: Trata-se de estudo transversal a partir da aplicação do questionário padrão do International Study of Asthma and Allergies in Chlidhood (ISAAC) e exame parasitológico de fezes para Ascaris lumbricoides. A variável dependente foi o diagnóstico de DA ausente, DA leve e DA grave. Efetuou-se análise de regressão logística multivariada, bem como análise descritiva das variáveis do estudo. As associações foram estimadas por meio de risco relativo (RR) e razão de chances (odds ratio, OR). A inferência estatística foi baseada em intervalos de confiança de 95% (IC95%). Resultados:Foram avaliadas 1.195 crianças, sendo 51,2% (n = 612) do sexo feminino. A prevalência de DA foi de 24,6%, e a de ascaridíase, de 26,1%. Das crianças com DA leve, 44 (36,7%) eram parasitadas pelo A. lumbricoides, enquanto que 40 (22,9%), com DA grave, apresentavam a mesma geo-helmintose (p = 0,01). Comparando-se os casos negativos para DA com os casos leves e graves, constatou-se que a presença de ascaridíase aumentou a ocorrência de dermatite leve (RR = 1,7; p = 0,009), mas não de DA grave (RR = 0,86; p = 0,46). Avaliando-se apenas os casos positivos de dermatite, DA leve (n = 120;...

Severity of atopic dermatitis and Ascaris lumbricoides infection: an evaluation of CCR4+ and CXCR3+ helper T cell frequency

“…In conclusion, our findings showed a high frequency of CCR4+Th2 cells in the peripheral blood of A. lumbricoides-free AD patients, in agreement with the high propensity for severe skin symptoms 8 . Besides, the finding that atopic dermatitis lowered the blood traffic of Th1 cells in the concomitant infected patients suggested that ascariasis and atopic phenotype can influence each other, modifying the blood traffic of Th2 and Th1 in patients with both diseases.…”

“…For the first time, our results showed that current A. lumbricoides infections in AD children from an urban area decreased the risk of severe AD symptoms 8 . We showed in this study that infected AD patients present a low frequency of CCR4+ lymphocytes, a membrane marker involved in Th2 cell chemotactic influx.…”

“…In contrast, it was demonstrated that previous or current A. lumbricoides infections can reduce the frequency of atopic eczema in schoolchildren 6,7 . Recently, we have observed that ascariasis decreased the frequency of severe dermatitis in children from an urban area endemic for this helminthiasis 8 . In this study, we investigated the frequency of CCR4+Th2 and CXCR3+Th1 cells in the peripheral blood of A. lumbricoides-infected AD children.…”

“…The study was performed in Pedregal, an area of low socioeconomic index in the City of Campina Grande, Brazil, where a high AD prevalence has been observed 8 . All parents or guardians of the children (aged 2 to 10 years), after providing written consent to take part in the study, were asked about AD symptoms through the questionnaire of the International Study of Asthma and Allergies in Childhood (ISAAC) 9 .…”

“…Epidemiological studies on the association between worm infestation and eczema are scarce [5][6][7][8] . For the first time, our results showed that current A. lumbricoides infections in AD children from an urban area decreased the risk of severe AD symptoms 8 .…”