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

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

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.

Study Overview

• Status: Unknown
• Conditions: 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 Type: Observational
• Enrollment (Anticipated): 110

Contacts and Locations

Study Locations

• Thailand
  • Bangkok, Thailand, 10700
    • Recruiting
    • Siriraj Hospital
    • Contact: Professor Pakit Vichyanond, MD; Phone Number: 9465-6 662-419-7000; Email: pakitv@gmail.com
    • Contact: Parawee Prottasan, MD; Phone Number: 5670, 5889 662-419-7000; Email: Parawee_p@hotmail.com
    • Principal Investigator: Professor Pakit Vichyanond, MD
    • Sub-Investigator: Professor Chaweewan Bunnag, MD
    • Sub-Investigator: Assistant Professor Pongsakorn Tantilipikorn, MD
    • Sub-Investigator: Professor Nualanong Visitsunthorn, MD
    • Sub-Investigator: Associate Professor Orathai Piboonpocanun, MD
    • Sub-Investigator: Punchama Pacharn, MD
    • Sub-Investigator: Parawee Prottasan, MD
    • Sub-Investigator: Triphoom Suwanwech, MD
    • Sub-Investigator: Chaweewan Sripramong, SC
    • Sub-Investigator: Unchalee Wangthan, SC

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 15 years to 60 years (Child, Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

allergic rhinitis patients in Siriraj hospital (tertiary care) control group: healthy subjects from community sample

Description

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

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
healthy subjects no symptoms
allergic rhinitis patient

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
appropriate concentration of diagnostic reagent of house dust mite (Dp)	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.	15 minutes

Secondary Outcome Measures

Outcome Measure	Time Frame
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

Collaborators and Investigators

• Sponsor: Siriraj Hospital
• Investigators: Principal Investigator: Professor Pakit Vichyanond, MD, Department of Pediatrics, Faculty of Medicine Siriraj Hospital, Mahidol University

Study record dates

Study Major Dates

• Study Start: June 1, 2010
• Primary Completion (Anticipated): December 1, 2010

Study Registration Dates

• First Submitted: July 29, 2010
• First Submitted That Met QC Criteria: July 29, 2010
• First Posted (Estimate): July 30, 2010

Study Record Updates

• Last Update Posted (Estimate): July 30, 2010
• Last Update Submitted That Met QC Criteria: July 29, 2010
• Last Verified: July 1, 2010

More Information

Terms related to this study

• Keywords: allergic rhinitis; skin prick test; concentration of diagnostic reagent; allergen extract, house dust mites (Dp); nasal allergen provocation test
• Additional Relevant MeSH Terms: Infections; Respiratory Tract Infections; Respiratory Tract Diseases; Immune System Diseases; Hypersensitivity, Immediate; Otorhinolaryngologic Diseases; Respiratory Hypersensitivity; Hypersensitivity; Nose Diseases; Rhinitis; Rhinitis, Allergic; Rhinitis, Allergic, Perennial; Rhinitis, Allergic, Seasonal
• Other Study ID Numbers: 112/2553(EC3)