DSPT: Optimal Concentration of Dermatophagoides Pteronyssinus (Dp) Allergen Extract for Skin Prick Test (SPT) of Thai Population

Sponsor

Siriraj Hospital (Other)

Overall Status

Unknown status

CT.gov ID

NCT01172613

Collaborator

(none)

110

Enrollment

Locations

Patients Per Site

Study Details

Study Description

Brief Summary

The purpose of this study is to determine the appropriate concentration of diagnostic reagent of house dust mite (Dp) to be used in diagnostic allergy skin prick test among Thai population with allergic rhinitis.

Condition or Disease	Intervention/Treatment	Phase
Rhinitis, Allergic, Perennial Rhinitis, Allergic, Seasonal Skin Prick Test

Detailed Description

The current allergy diagnostic reagent of house dust mites marketed in the USA is at 10,000 AU/ml. This is based on the IDEAL50 concept put forth by Turkeltaub et al, almost 3 decades ago. Such concentration has been shown to give large degree of false positives even in the US population.

In Thailand, it was anecdotally observed that at such concentration, sizes of positive tests among atopic subjects were quite large and could lead to discomfort and a possible anaphylaxis in certain allergic individuals. Moreover, up to 40% of normal individuals could give positive reaction to this concentration.

It is therefore desirable to reexamine the appropriate concentration of diagnostic reagent of house dust mites among the Thai population and will be the main objective of this research.

Study Design

Study Type:

Observational

Anticipated Enrollment :

110 participants

Observational Model:

Case-Control

Time Perspective:

Cross-Sectional

Official Title:

Optimal Concentration of Allergen Extract of Dermatophagoides Pteronyssinus to be Used in Diagnostic Allergy Skin Prick Test Among Thai Population

Study Start Date :

Jun 1, 2010

Anticipated Primary Completion Date :

Dec 1, 2010

Arms and Interventions

Arm	Intervention/Treatment
healthy subjects no symptoms
allergic rhinitis patient

Outcome Measures

Primary Outcome Measures

appropriate concentration of diagnostic reagent of house dust mite (Dp) [15 minutes]
to determine appropriate dilutional concentration of diagnostic reagent of house dust mite (Dp) that has high sensitivity and positive predictive value and wheal size not more than 10 mm. to be used in diagnosis allergic rhinitis in Thai population by skin prick test.

Secondary Outcome Measures

false positive rates of various dilutions of diagnostic reagent (house dust mite: Dp) that be used in skin prick test in Thai healthy population [15 minutes]
false negative rates of various dilutions of diagnostic reagent (house dust mite: Dp) that be used for diagnosis allergic rhinitis in Thai population by skin prick test [15 minutes]

Eligibility Criteria

Criteria

Ages Eligible for Study:

15 Years to 60 Years

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Yes

Inclusion Criteria:allergic rhinitis

clinical diagnosis of allergic rhinitis
has skin prick test positive to standard Dp extract (wheal diameter 3 mm. or greater)
not take any medications that interfere the tests (skin prick test and nasal allergen provocation test)

Inclusion Criteria:healthy subject

no underlying disease
not take any medications that interfere the tests (skin prick test and nasal allergen provocation test)

Exclusion Criteria:

has skin prick test positive to standard Dp extract with wheal diameter more than 10 mm.
has chronic disease eg. HIV infection, neurological diseases, hypertension, cardiac diseases, pulmonary diseases, hepatobiliary diseases, renal diseases, endocrinological diseases, congenital malformation, malignancy
if has asthma, uncontrolled asthma symptom or PEF < 70%
during pregnancy or lactation
has chronic skin disease
participate other project within 30 days
has abnormal anatomy of the nose