Association between giardiasis and allergy.
BACKGROUND
Previous studies have indicated that there may be an association between infection by the intestinal protozoan Giardia lamblia and the expression of allergic disease.


OBJECTIVE
We evaluated a group of children who attended the Outpatient Clinic of the Children's Hospital in Caracas, Venezuela, a group in which both allergic disease and giardiasis were common.


METHODS
We performed feces examination and measured total and specific serum IgE (immunoglobulin E) in these children.


RESULTS
We found that 70% of the children infected with G. lamblia presented symptoms of allergy, in contrast to 43% of the non-Giardia parasitized group (P <.05). In addition, the G. lamblia parasitized children showed significantly higher levels of total serum IgE (1194 IU/mL) than the non-Giardia group (822 IU/mL) (P <.005). Children infected with G. lamblia showed higher levels of specific serum IgE antibody against food allergens compared both with the non-parasitized group (P <.0001) and children infected with parasites other than Giardia (P <.05). In contrast, IgE responses against the house dust mite Dermatophagoides pteronyssinus were similar in all the groups studied.


CONCLUSIONS
These results reveal a clear relationship between giardiasis and allergy, possibly because infection by this protozoon enhances sensitization towards food antigens, due to increased antigen penetration through damaged intestinal mucosa.
Institute of Biomedicine, Central University of Venezuela, Caracas.
M C
MC
Di Prisco
I
I
Hagel
N R
NR
Lynch
J C
JC
Jiménez
R
R
Rojas
M
M
Gil
E
E
Mata
D000913:Antibodies, Protozoan / Q000097:blood; D002648:Child; D002675:Child, Preschool; D005260:Female; D005512:Food Hypersensitivity / Q000469:parasitology; D005873:Giardiasis / Q000097:blood / Q000453:epidemiology* / Q000276:immunology*; D006801:Humans; D006967:Hypersensitivity / Q000453:epidemiology* / Q000469:parasitology; D007073:Immunoglobulin E / Q000097:blood; D008297:Male; D012130:Respiratory Hypersensitivity / Q000469:parasitology; D014687:Venezuela / Q000453:epidemiology
D000913:Antibodies, Protozoan; D007073:Immunoglobulin E