The Turkish Journal of Pediatrics
2009 , Vol 51 , Num 3
Exposure to house dust endotoxin and allergic sensitization in allergic and nonallergic children living in Adana, Turkey
Division of Pediatric Allergy and Immunology, Department of Pediatrics1,Department of Pubic Health, Çukurova University Faculty of Medicine, Adana, Turkey2,
It has been suggested that exposure to elevated levels of endotoxin decreases
the risk of allergic sensitization. The objective of our study was to analyze
associations between house dust endotoxin levels and allergic sensitization
in children.
One hundred children with self-reported allergic diseases and 100 healthy
children were randomly selected from a list of a previous prevalence study in
school children. These children attended the study center again to complete
a detailed questionnaire and medical examination including skin prick test
and pulmonary function test. Of these children, 65 had allergen sensitization.
Parents of a total 100 children (50 allergic and 50 healthy) agreed to house
dust sampling in their homes. Thirty-five allergic children had asthma and
25 had rhinitis. Thirteen allergic and 14 healthy children lived in rural areas.
The endotoxin content was quantified using a chromogenic kinetic Limulus
amoebocyte lysate test.
Endotoxin was at a detectable level in all dust samples. Endotoxin levels
ranged from 0.05 to 309 EU/ml, with a geometric mean of 61.8 (confidence
interval [CI] %) (50-73) EU/ml. There were no differences in house dust
endotoxin levels between allergic and nonallergic children (p=0.153). On the
whole, the mean level of endotoxin in rural homes was higher than that of
urban homes, but this was not statistically significant (p=0.354). The highest
endotoxin level was found in the homes of nonallergic children living in the
rural areas and the lowest level in the homes of allergic children living in an
urban area; however, this was not important statistically (p=0.320). Exposure
to endotoxin was not associated with a risk of allergic sensitization (odds
ratio [OR]=0.98; 95% CI: 0.91-1.05, p=0.609).
In conclusion, supposing that the current level of endotoxin may reflect that
in the past, the levels of endotoxin in living room floor dust of homes of
allergic and nonallergic children in our study population were not associated
with allergic sensitization. Further studies are needed on this topic.
Keywords :
allergy, asthma, endotoxin, children.