Test: Skin Prick Test - Cat

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Background/Purpose

Cats produce multiple allergens (proteins that can cause allergy). These allergens are found on the fur and skin and in saliva. All cats produce allergens; studies have not shown that cats can be hypoallergenic (meaning that they don’t cause allergy). Homes with more than one cat have higher levels of cat allergens. Characteristics such as the length of a cat’s hair, its sex and the amount of time a cat spends indoors are not associated with cat allergen levels.

Procedure

The test area is cleaned and labeled using an appropriate skin marker. When multiple tests are being performed there should be a minimum of of 3cm between them. The skin is pricked lightly and quickly vertically through the sample allergen . A new micro lancet should be used for each substance being tested. The excess sample allergen should be removed immediately with an absorbent paper towel.
The wheals should be read after 15-20 minutes. For a positive reaction, the wheal should be >= 3mm in diameter. A valid result also requires a positive histamine reaction >=3mm and a negative saline control reaction of < 3mm.
Performed: Bilaterally

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Skin prick test of cat allergens.

Criteria

• <3mm wheal
• No systemic reaction

Measurement

LOINC Code

Scale/Grading

selection range; grade - LOINC ID
Option - Value option selection range; grade - LOINC IDPass < 3 ; Pass - Equivocal = 3 ; Fail - Fail > 3 ; Fail -