For the first time, German researchers have demonstrated that exposure to house dust endotoxin is associated with a lower prevalence of allergic sensitization in school children. The researchers compared the effects of house dust endotoxins on different degrees of allergic sensitization in 444 boys and girls aged 5 to 10 years. (Endotoxins, present as common constituents of house dust, are cell wall components of the outer membrane of gram-negative bacteria. They are known to have both strong immuno-stimulatory and pro-inflammatory properties.) The investigators found that exposure to higher levels of house dust endotoxin in particular decreases the risk of more severe sensitization. They revealed that children who had lived in the same house since birth showed stronger endotoxin effects on sensitization to any allergen than did those who had moved. They believe that living in the same home offers a better estimate of endotoxin exposure in early life. Fifty percent of the children were either atopic (had an inherited tendency toward allergy), or had a physician diagnosis of asthma. Blood samples from each child and dust samples from the living room floor of each house were available for all participants. The research appears in the first issue for October 2002 of the American Thoracic Society's peer-reviewed American Journal of Respiratory and Critical Care Medicine.
FEMALES MORE COUGH SENSITIVE THAN MALES
Researchers testing the responses of both sexes to tussive agents showed that cough sensitivity was greater in females than males at a clinic for chronic cough. Investigators tested a total of 118 patients, including 68 females and 50 males, with inhalation cough challenges. The inhalation cough challenge materials were inhaled through a mouthpiece for 1 second and the number of coughs in the first 10 seconds after inhalati
Contact: Cathy Carlomagno
American Thoracic Society