Endotoxin exposure and symptoms in asthmatic children

Pediatr Allergy Immunol. 1997 Aug;8(3):121-6. doi: 10.1111/j.1399-3038.1997.tb00164.x.


Endotoxins (ET) are pro-inflammatory substances present in house dust which may increase non-specific bronchial reactivity in asthmatic patients. Endotoxins (EU/g) and Der p 1 levels were compared in the homes of ten asthmatic and ten control children, aged 6-16 years, living in São Paulo, Brazil. The houses were visited once a month from February 1993 to February 1994 and dust samples were collected from the bedding and floor of each subject's house. No significant differences were observed in ET and Der p 1 levels in the homes of asthmatics and controls. The highest ET levels were detected in January and November, whereas the lowest levels were detected in April and August (p < 0.05), demonstrating a distinct seasonal distribution. The highest Der p 1 levels in bedding were observed in July and the lowest in February (p < 0.05), while Der p 1 levels in floor did not show significant differences throughout the year. Symptom and medication scores were evaluated monthly in the group of asthmatic children. There was a significant correlation (p < 0.05, r = 0.63) between clinical symptom scores and ET exposure, however no significant correlation was found for mite exposure (p > 0.05, r = 0.19). The results suggest that ET exposure exacerbates asthmatic symptoms in mite allergic, asthmatic children.

MeSH terms

  • Adolescent
  • Allergens / adverse effects
  • Allergens / blood
  • Antigens, Dermatophagoides
  • Asthma / blood*
  • Asthma / complications
  • Child
  • Dust
  • Female
  • Glycoproteins / blood*
  • Humans
  • Immunoglobulin E / blood
  • Immunosorbents
  • Male
  • Prospective Studies
  • Radioallergosorbent Test / methods
  • Statistics, Nonparametric


  • Allergens
  • Antigens, Dermatophagoides
  • Dust
  • Glycoproteins
  • Immunosorbents
  • Immunoglobulin E