Oral Bacteria and Allergic Disease in Children

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00438646
Recruitment Status : Completed
First Posted : February 22, 2007
Last Update Posted : August 25, 2009
Information provided by:
National Institutes of Health Clinical Center (CC)

Brief 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).

Condition or disease
Asthma Rhinitis Eczema Respiratory Sounds Hypersensitivity

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.

Study Type : Observational
Enrollment : 60 participants
Time Perspective: Prospective
Official Title: Oral Bacteria and History of Allergic Disease in Children: A Pilot Study
Study Start Date : February 2007
Actual Primary Completion Date : December 2008

Resource links provided by the National Library of Medicine

U.S. FDA Resources

Information from the National Library of Medicine

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Ages Eligible for Study:   6 Years to 11 Years   (Child)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

    1. Aged 6-11 years.
    2. Child is presenting to the UNC-CH School of Dentistry for a scheduled appointment.
    3. Sibling has not been enrolled.
    4. Parent consents to child's participation.
    5. Parent is willing to provide answers to a questionnaire.
    6. Child assents to the study.
    7. Child is willing and able to provide a usable saliva sample.


  1. Child is unwilling or unable to provide a usable saliva sample.
  2. Parent or child is non-English speaking.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00438646

United States, North Carolina
University of North Carolina at Chapel Hill
Chapel Hill, North Carolina, United States
Sponsors and Collaborators
National Institute of Environmental Health Sciences (NIEHS)

Publications: Identifier: NCT00438646     History of Changes
Other Study ID Numbers: 999907109
First Posted: February 22, 2007    Key Record Dates
Last Update Posted: August 25, 2009
Last Verified: November 2008

Keywords provided by National Institutes of Health Clinical Center (CC):
Hay Fever

Additional relevant MeSH terms:
Respiratory Sounds
Nose Diseases
Respiratory Tract Diseases
Respiratory Tract Infections
Otorhinolaryngologic Diseases
Immune System Diseases
Skin Diseases
Skin Diseases, Eczematous
Signs and Symptoms, Respiratory
Signs and Symptoms