Pediatric Allergy Testing for Contact Dermatitis in Illinois
Patch testing is a way for doctors to determine the potential causes of contact dermatitis, which is an immunological response to specific substances. Patch testing is particularly useful as it may identify allergens that were not detected during other tests such as skin prick, or blood tests. Contact dermatitis is not an actual allergy, and therefore there are no allergic antibodies. Instead, contact dermatitis reactions are caused by white blood cells.
Prior to testing, the doctor will complete an evaluation, which will include questions about your rash. It is important to share when and where the rashes occur on the skin. If you have your suspicions about the cause of your reaction, share that with your doctor as well. Patients will need to discontinue use of any anti-histamines prior to the test.
The test involves applying multiple chemicals (the most common known offenders of reactions) onto the skin held in place by a special type of tape. The chemicals are contained within metal discs that are smaller in diameter than a dime. Patch testing does not involve the use of needles. The discs are then left on the skin undisturbed for 48 hours. It is important to keep the discs dry; therefore, patients will need to avoid showers or excessive sweating.
After 48 hours, the patch tests are removed for a reading. Marks are placed on the back prior to removal and an additional reading will be taken in approximately 96 hours after placement.
If the final reading indicates positive reaction to certain chemicals, treatment options can be discussed. One of the best forms of treatment is avoidance of the particular allergen.
Patch testing is not painful and is extremely safe for children. It is important for the tape to remain intact, so the only caveat is the child should be old enough to understand this.
The patch testing itself will cause small areas of contact dermatitis. Side effects from the test may be itching underneath the tape. Patients who test positive for certain chemicals may see bumps, swelling, redness, or blisters in that area. After the testing, patients will be given a topical medication to treat the reaction and relieve itching.Back to Patch Testing Page