Sensitization to Ascaris lumbricoides and severity of childhood asthma in Costa Rica.
BACKGROUND
Little is known about sensitization (defined as a positive IgE) to helminths and disease severity in patients with asthma.


OBJECTIVE
To examine the relationship between sensitization (defined as a positive IgE) to Ascaris lumbricoides and measures of asthma morbidity and severity in a Costa Rican population with low prevalence of parasitic infection but high prevalence of parasitic exposure.


METHODS
Cross-sectional study of 439 children (ages 6 to 14 years) with asthma. Linear regression and logistic regression were used for the multivariate statistical analysis.


RESULTS
After adjustment for parental education and other covariates, sensitization to Ascaris lumbricoides was associated with having at least 1 positive skin test to allergens (odds ratio, 5.15; 95% CI, 2.36-11.21; P < .001), increased total serum IgE and eosinophils in peripheral blood, reductions in FEV(1) and FEV(1)/forced vital capacity, increased airway responsiveness and bronchodilator responsiveness, and hospitalizations for asthma in the previous year (odds ratio, 3.08; 95% CI, 1.23-7.68; P = .02).


CONCLUSIONS
Sensitization to Ascaris lumbricoides is associated with increased severity and morbidity of asthma among children in Costa Rica. This association is likely mediated by an increased degree of atopy among children with asthma who are sensitized to Ascaris.


CONCLUSIONS
In areas with a low prevalence of helminthiasis such as Costa Rica, Ascaris sensitization may be an important marker of severe atopy and disease morbidity in children with asthma.
Hunninghake
Gary M
GM
Channing Laboratory, Division of Pulmonary and Critical Care Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
Soto-Quiros
Manuel E
ME
Avila
Lydiana
L
Ly
Ngoc P
NP
Liang
Catherine
C
Sylvia
Jody S
JS
Klanderman
Barbara J
BJ
Silverman
Edwin K
EK
Celedón
Juan C
JC
D000485:Allergens / Q000276:immunology*; D000818:Animals; D017164:Ascaris lumbricoides / Q000276:immunology*; D001249:Asthma / Q000150:complications* / Q000453:epidemiology*; D001993:Bronchodilator Agents / Q000494:pharmacology; D002000:Bronchospirometry; D002648:Child; D003364:Costa Rica / Q000453:epidemiology; D004804:Eosinophils / Q000166:cytology; D005260:Female; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000150:complications* / Q000276:immunology; D007073:Immunoglobulin E / Q000097:blood; D007958:Leukocyte Count; D008168:Lung / Q000187:drug effects / Q000503:physiopathology; D008297:Male; D015995:Prevalence; D012882:Skin Tests
D000485:Allergens; D001993:Bronchodilator Agents; D007073:Immunoglobulin E