Exposure to house dust endotoxin and allergic sensitization in adults

Allergy. 2004 Sep;59(9):946-52. doi: 10.1111/j.1398-9995.2004.00551.x.


Background: It has been suggested that exposure to elevated levels of endotoxin decreases the risk of allergic sensitization.

Objective: To examine the associations between current exposure to bacterial endotoxin in house dust and allergic sensitization in adults.

Methods: In 1995-1996, we conducted a nested case-control study following a cross-sectional study performed within the European Community Respiratory Health Survey (ECRHS). Data of 350 adults aged 25-50 years was analysed. Allergic sensitization was assessed by measurement of specific immunoglobulin E (IgE) against several inhalant allergens. Living room floor dust samples were taken. The endotoxin content was quantified using a chromogenic kinetic Limulus amoebocyte lysate test.

Results: Multiple logistic regression analysis showed a negative association between exposure to house dust endotoxin and severe allergic sensitization. Odds ratios (95% CI) adjusted for place of residence, gender, age, and 'caseness' were 0.80 (0.64-1.00) for sensitization to >/=1 allergen and 0.72 (0.56, 0.92) for sensitization to >/=2 allergens using 3.5 kU/l as a cut-off value for sensitization. With regard to single allergens, the protective effect of endotoxin was strongest for pollen sensitization [aOR (95% CI) = 0.74 (0.58, 0.93)].

Conclusion: Our results indicate that current exposure to higher levels of house dust endotoxin might be associated with a decreased odds of allergic sensitization in adults.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Allergens / immunology
  • Case-Control Studies
  • Cross-Sectional Studies
  • Dust / immunology*
  • Endotoxins / pharmacology*
  • Female
  • Humans
  • Hypersensitivity / prevention & control*
  • Immunoglobulin E / blood
  • Logistic Models
  • Male
  • Middle Aged


  • Allergens
  • Dust
  • Endotoxins
  • Immunoglobulin E