How is a skin test for ticks conducted? - briefly
A minute amount of tick antigen is injected intradermally, typically on the forearm, and the injection site is inspected after 15–20 minutes for a wheal and surrounding erythema that signify a positive response. The outcome assists clinicians in confirming exposure to tick-borne pathogens.
How is a skin test for ticks conducted? - in detail
A tick skin test is performed by applying a small amount of tick‑derived allergen to the epidermis and observing the local immune reaction. The procedure follows a strict sequence to ensure reliability and safety.
First, the clinician verifies that the patient has no contraindications, such as severe dermatologic conditions, anticoagulant therapy, or a history of anaphylaxis. Informed consent is obtained and the patient’s medical record is reviewed for prior tick exposures.
Next, the test site—usually the volar forearm—is cleaned with an antiseptic solution (e.g., 70 % isopropyl alcohol) and allowed to dry. A sterile lancet is used to create a shallow puncture, approximately 2 mm deep, at a predefined location. The allergen preparation, standardized to a specific protein concentration, is delivered onto the puncture using a calibrated micropipette (typically 0.02 ml). A negative control (saline) and a positive control (histamine) are placed on separate punctures to validate the reaction.
The test area is covered with a transparent, non‑adhesive dressing to prevent contamination and to maintain humidity. The patient remains seated for 15 minutes, after which the dressing is removed. The clinician measures the diameter of any wheal and erythema at the test site with a ruler or caliper. A wheal larger than 3 mm accompanied by surrounding erythema, compared with the control readings, constitutes a positive result.
The results are recorded in the patient’s chart, noting the exact measurements, the time of reading, and any adverse symptoms such as itching or systemic reactions. If a positive response occurs, the clinician may recommend further evaluation, including specific IgE testing or desensitization protocols.
All used materials—lancets, pipettes, dressings—are disposed of according to biohazard regulations. The workstation is disinfected, and any leftover allergen is discarded following manufacturer guidelines.