Oral Bacteria and Allergic Disease in Children
Condition: Asthma; Rhinitis; Eczema; Respiratory Sounds; Hypersensitivity
MeSH terms: Rhinitis; Eczema; Hypersensitivity; Respiratory Sounds
Study type: Observational

Summary: 
      This study will see if bacteria differ between children who have allergies or asthma and
      children who do not have allergies or asthma. Previous research suggests that some bacteria
      may protect against allergies and asthma. This study may provide more information on why some
      children develop allergies and asthma.

      Patients at the University of North Carolina-Chapel Hill School of Dentistry who are between
      6 and 11 years of age may be eligible for this study.

      Parents of participating children complete a questionnaire about the child and the child's
      health. The child provides a saliva sample by chewing a small piece of wax and spitting in a
      cup.

      The saliva sample is analyzed in the laboratory for bacteria, yeast and antibodies
      (substances the body produces to fight germs).

      ...
    

Detailed description: 
      The purpose of this study is to examine the feasibility of and to establish methods for a
      future study that will investigate associations between oral bacteria and allergic diseases
      in children. Rates of allergic diseases such as asthma, hay fever, and eczema have increased
      in the U.S. over the past several decades. One explanation for those increases is the Hygiene
      Hypothesis, which contends that decreases in microbial exposures have made the population
      more reactive to environmental allergens. Reports of protective associations for various
      infections and exposures to farms, pets, siblings, and day care have provided support for the
      Hypothesis. Preliminary work by NIEHS researchers suggests that some oral bacterial exposures
      may be beneficial. NIEHS researchers recently reported that elevated serum antibody
      concentrations to two common oral pathogens were associated with lower prevalences of asthma,
      wheeze, and hay fever in the U.S. population. Using a mouse model, NIEHS researchers found
      that immune responses involved in allergic airway inflammation could be modulated by
      infection with an oral pathogen. To further investigate these associations in humans, NIEHS
      researchers, in collaboration with UNC researchers, are planning an observational study that
      will collect saliva samples from and allergy information on child patients at the UNC-Chapel
      Hill School of Dentistry. Because we anticipate that several hundred children might have to
      be enrolled, we are proposing to test methods in a pilot study of 60 children. Twenty
      children will be recruited from each of three pediatric clinics. A research assistant will
      obtain the parent's consent and the child's assent and administer a questionnaire to the
      parent. The child's dentist will collect one teaspoon of saliva by having the child chew a
      piece of inert wax and spit into a sterile collection cup. Samples will be transported to the
      NIEHS and analyzed for bacterial species and for allergy-related cytokines. The specific aims
      for this pilot study are: 1) to identify the most efficient recruitment strategies, 2) to
      estimate response rates, 3) to estimate the distribution of allergic diseases among the
      children, 4) to identify any problematic consent form and questionnaire items, 5) to optimize
      saliva collection and laboratory protocols, and 6) to estimate statistical parameters
      required for more precise sample size calculations. Information gained from this pilot study
      will allow us to decide whether a larger study among this clinic population is feasible and
      to design a more efficient study if we decide to proceed.
    

Time perspective: Prospective
Keywords: Allergy; Asthma; Eczema; Hay Fever; Epidemiology