Mechanisms of asthma and allergic inflammationSensitization to Ascaris lumbricoides and severity of childhood asthma in Costa Rica
Section snippets
Study population
Children who participated in this study were index cases for a genetic study of nuclear families of children with asthma in Costa Rica. From February 2001 to March 2005, short questionnaires were sent to the parents of 9054 children age 6 to 14 years who were enrolled in 95 schools in Costa Rica. Of the questionnaires distributed, 5355 (59.1%) were returned. Children were eligible for inclusion in the study if they had asthma (defined as physician-diagnosed asthma and at least 2 respiratory
Results
A comparison of selected characteristics of children who were (n = 171) and were not (n = 268) sensitized to Ascaris is presented in Tables I (for categorical variables) and II (for continuous variables). Children who were sensitized to Ascaris were more likely to be boys, to have been hospitalized for asthma in the previous year, and to have at least 1 positive skin test to allergens, a positive IgE to dust mite or cockroach, markedly increased airway responsiveness to methacholine (a 20% fall
Discussion
To our knowledge, this is the first report of an association between sensitization to A lumbricoides and increased asthma morbidity. Among children with asthma in Costa Rica, sensitization to Ascaris was associated with increased odds of allergic sensitization, increased levels of total serum IgE and eosinophils in peripheral blood, increased airway responsiveness and bronchodilator responsiveness, reduced lung function, and hospitalizations for asthma in the previous year.
Studies of children
References (41)
Ascariasis
Gastroenterol Clin North Am
(1996)- et al.
Effect of anthelmintic treatment on the allergic reactivity of children in a tropical slum
J Allergy Clin Immunol
(1993) - et al.
Reduced risk of atopy among school-age children infected with geohelminth parasites in a rural area of the tropics
J Allergy Clin Immunol
(2003) - et al.
Independent effects of intestinal parasite infection and domestic allergen exposure on risk of wheeze in Ethiopia: a nested case-control study
Lancet
(2001) - et al.
Risk factors for wheezing in a subtropical environment: role of respiratory viruses and allergen sensitization
J Allergy Clin Immunol
(2004) - et al.
Ascaris-specific IgE and allergic sensitization in a cohort of school children in the former East Germany
J Allergy Clin Immunol
(1998) - et al.
Which clinical subgroups within the spectrum of child asthma are attributable to atopy?
Chest
(2002) - et al.
Relationship between helminthic infection and IgE response in atopic and nonatopic children in a tropical environment
J Allergy Clin Immunol
(1998) - et al.
Effect of albendazole treatments on the prevalence of atopy in children living in communities endemic for geohelminth parasites: a cluster-randomised trial
Lancet
(2006) - et al.
The evaluation of potential global morbidity attributable to intestinal nematode infections
Parasitology
(1994)
Allergic symptoms, atopy, and geohelminth infections in a rural area of Ecuador
Am J Respir Crit Care Med
Ministerio de Salud. Encuesta Nacional de Nutricion, 1996: Helmintos Intestinales
Normas de Atencion Integral de Salud, Primer Nivel de Atención
Intestinal worms and human allergy
Parasite Immunol
Ascaris lumbricoides infection is associated with increased risk of childhood asthma and atopy in rural China
Am J Respir Crit Care Med
Clinical improvement of asthma after anthelminthic treatment in a tropical situation
Am J Respir Crit Care Med
Worldwide variation in prevalence of symptoms of asthma, allergic rhinoconjunctivitis, and atopic eczema: ISAAC. The International Study of Asthma and Allergies in Childhood (ISAAC) Steering Committee
Lancet
Use of linkage disequilibrium approaches to map genes for bipolar disorder in the Costa Rican population
Am J Med Genet
Collaborative studies on the genetics of asthma: National Heart, Lung and Blood Institute
Clin Exp Allergy
Cited by (0)
Supported by grants HL04370 and HL66289 from the National Institutes of Health.
Disclosure of potential conflict of interest: E. K. Silverman has consulting arrangements with GlaxoSmithKline, has received grant support from GlaxoSmithKline, has received honoraria from Bayer, and received money from Wyeth for a talk on chronic obstructive pulmonary disease genetics. The rest of the authors have declared that they have no conflict of interest.