Standardization of the prick test. A comparative study of three methods

Area of Science:

• Allergy and Immunology
• Dermatological Testing

Background:

• Skin prick testing is crucial for allergy diagnosis and extract standardization.
• Variability in needles and methods leads to inconsistent prick test results.
• Ensuring test reliability is essential for accurate clinical application.

Purpose of the Study:

• To evaluate the reproducibility of different needles and methods in skin prick testing.
• To identify the most reliable technique for consistent allergy testing outcomes.

Main Methods:

• A comparative study involving 30 subjects (allergic and healthy individuals).
• Three types of needles were used: Allergy Pricker, Morrow-Brown needle, and Insulin needle (Pepys method).
• 810 total prick tests were performed across three different testers.

Main Results:

• The Allergy Pricker demonstrated high reproducibility, with no significant variation between testers or within the same individual.
• The Morrow-Brown needle showed significant variability and frequent false-negative results.
• The Pepys method avoided false negatives but exhibited considerable wheal size variation (coefficient of variation 64%).

Conclusions:

• The Allergy Pricker offers the highest degree of reproducibility in skin prick testing.
• Standardizing prick test methods, specifically needle choice, is vital for reliable allergy diagnostics.
• The Allergy Pricker is recommended for multi-center studies and allergenic extract standardization.