Patch Testing

As a fellow of the American Contact Dermatitis Society (ACDS), Dr. Buster is highly trained in the diagnosis and treatment of allergic contact dermatitis. She is currently one of only two ACDS Fellows in Tulsa, OK.

 

What is contact dermatitis?

Contact dermatitis (CD) is simply a rash secondary to skin coming into contact with a substance. CD is common with estimated rates in the U.S. between 1.5% and 5.4% and accounting for millions of dermatology visits per year. (1) There are two types of CD—allergic and irritant.

Nearly everyone is familiar with the rash caused by poison ivy. That is a good example of skin allergy better known as allergic contact dermatitis (ACD). Over half of the U.S. population is allergic to poison ivy and will develop an itchy rash when exposed to the plant. (2) Poison ivy induced ACD is usually easily recognized, but there are MANY other substances that cause ACD and the trigger of the rash can sometimes be subtle. Besides itch, ACD may cause a number of other signs including erythema (redness), blisters, whelps (hives), and burning.

Here are some examples of sources of ACD:

  • Personal care products such as soaps, lotions, hair care products, make-up, and even some sunscreens.
  • Work-related items including latex gloves, rubber boots, cleaning solutions, plants, and detergents.
  • Sport- and fitness-related items such as shin guards, helmets, and wearables (e.g., FitBit)
  • Clothing-related substances such as fabric dyes, dry-cleaning chemicals, laundry detergent, dryer sheets, and elastic bands.
  • Metals—the most common of which is nickel. Other metals can also cause ACD including gold, copper, and cobalt.

Chemicals in many every day items we use can be harmless to most people, but cause ACD in a small number of those exposed to them. Having itch with or without rash may be a sign that you have ACD. ACD can lasts weeks to months and can be miserable for those who are unable to identify the trigger agent(s).

Not every rash due to contact with a substance is ACD. Irritant contact dermatitis (ICD) can develop from exposure to irritating products, ingredients, and materials or even over-exposure to normally non-irritating substances. In contrast to ACD, anyone can get ICD if exposed to enough irritant. Also, some items can cause BOTH ACD and ICD. For example, a ring containing nickel can cause ACD in someone allergic to nickel. However, someone NOT allergic to nickel can also develop a rash (ICD) under a ring containing any metal due to accumulation of soaps, sweat, and/or other substances under the band that eventually breakdown the skin’s protective barrier and cause inflammation and irritation.

 

What is patch testing?

Patch testing is a tool used primarily by dermatologists to assess for ACD to specific substances. During the test, multiple patches containing small amounts of substances that cause rash are applied to the skin—usually the back. Unlike scratch/prick testing, patch testing is not painful and no needles are used. Patches are left on for two days and then removed so that Dr. Buster can interpret the results.  The test site is typically examined by Dr. Buster 48-96 hours after placement. In some cases, we will have you return to the office again 1 week after patches were placed to assess for a delayed reaction.

Many dermatologists who offer patch testing utilize the T.R.U.E. Test, which tests for 35 allergens. I’ve used this in the past. Though it is a good start, smaller patch test series have been implicated with only completely evaluating about 28% of people tested in comparison to larger patch tests series. (3) At our office we test for reaction to 80 substances in our standard series—increasing the likelihood of determining what skin allergies you have. In addition to our standard test series, we have access to more than 800 allergens to perform customized patch testing when necessary.

 

What’s the process?

Typically patients will be seen for a consult and then for 3 patch test visits. Patch test visits are usually Monday, Wednesday, and Friday:

  • Consult: Dr. Buster gathers information and determines which patch testing is needed, if any (standard vs. customized patch testing).
  • Patch Visit #1: placement of patches (sometimes this can occur at first visit)
  • Patch Visit #2: patch removal +/- initial reading
  • Patch Visit #3: reading, review of results, and education including a personalized list of products you CAN use based on test results
  • (Patch Visit #4): sometimes a delayed reading is needed at about 1 week out

Most patients will only need the standard patch series that includes 80 tests. However, if at your consult Dr. Buster determines that you will need a customized patch test series, we will order your tests and schedule your patch testing for a later date.

 

What are some things I need to know before having patch testing?

 Patch testing does require some preparation and planning:

  • Avoid topical steroids on sites where tests will be applied for at least 2 weeks prior to patch testing.
  • Oral steroids can mask skin allergy and make patch test results falsely negative. In most cases, Dr. Buster will have you stop any oral steroids you are on 2 weeks prior to placing patches. DO NOT stop oral steroids on your own/without specific instructions from Dr. Buster or your referring physician. Oral steroids cannot be abruptly discontinued (when they have been used chronically) without potentially serious—even life-threatening—adverse health effects. If you must be on steroids for other medical conditions (e.g., lupus, rheumatoid arthritis, etc.), Dr. Buster will typically coordinate with your other physician(s) to safely lower the dose temporarily to minimize likelihood of patch test false negatives without adversely affecting your health.
  • Avoid excess sun on the area to be tested for at least 4 weeks before testing.
  • When you come to have patches placed and removed, wear clothing that you don’t mind possibly being permanently stained with marker.
  • Once patches are in place, keep the test sites dry so patches stay on. Avoid:
    • Swimming
    • Excess sweating
    • Showering or soaking baths (you can sponge bathe until patches are removed)
    • Rubbing the patches
  • Once patches are removed avoid:
    • Scrubbing test sites (though gentle washing/showing is fine)
    • Getting excess sun on test sites

     

What are the results?

Patch test results can be positive, negative, irritant (not an allergy), or unclear. Positive reactions can be weak (pink/red) to strong with very strong reactions inducing blisters and even occasionally ulcers. Strong, itchy and/or irritated reactions can be treated once results are interpreted.

If a person has a significant amount of rash elsewhere or if they are allergic to a number of allergens, sometimes they can develop a so-called “angry back” where most—if not all—of the patch spots react. This is an over-reaction of the skin and does not represent a true allergy to everything. In such cases the skin must be allowed to calm down before reassessing and may require re-testing with fewer allergens to narrow down the trigger(s).

Dr. Buster evaluates all positive tests to determine their relevance and reviews that information with you. Rather than giving you a daunting list of ingredients you must avoid (which inevitably leads to exhaustive label reading and frustration), Dr. Buster gives you access to a personalized list of products that—based on your patch test results—should be safe for you to use without triggering your ACD. As a fellow of the American Contact Dermatitis Society, Dr. Buster is one of very few physicians in Tulsa with access to this database.

Negative patch test results typically mean that either you do not have ACD, or you have ACD to a compound which was not used in your patch testing. The panel we use at VibrantSkin is the Core Allergen Series—the patch test series recommended by the American Contact Dermatitis Society. Dr. Buster selected this panel because a significant number of ACD cases are caused by substances included in this panel. 

 

How much does it cost?

Our office has a unique set up as we do not accept commercial or government insurance. This allows us to directly care for our patients without delays or denials. Our current price for the standard patch testing series, which includes the three to four Patch Test Visits (see above), is $750 including all patches and all patch test visits, but NOT including the initial consult. Because we have a direct patient care model practice, we are able to offer patch testing at a much lower rate than many other practices. Should you desire/require a separate consult prior to patch test placement, pricing is time based. Please see our pricing page here for details. We do not require referrals. If you require additional or separate customized patch testing, pricing is based on the cost of such series and will be discussed with you.

 

*Please note that prices are subject to change at any time without notice.*

 

Interested in having patch testing at VibrantSkin?

Please call our office at (918) 340-6539 to schedule a consult visit with Dr. Buster. Ready to get started? Bring this completed form to your appointment to expedite your visit.

 

Want to refer a patient for patch testing at VibrantSkin?

Please fax your referral and patient information to us at (918) 932-2202. We can usually get patients in within a week of your referral.

  _______________________________________________________________________

 

  1. What is a patch test? 
    https://www.smartpractice.com/shop/wa/category?cn=Education-What-Is-a-Patch-Test%3F&id=508245&m=SPA
  2. Stephanides, S. Toxicodendron Poinsoning.                             https://emedicine.medscape.com/article/817671-overview
  1. Schalock, P., et al. American Contact Dermatitis Society Core Allergen Series.
    https://www.contactderm.org/files/public/2013_CoreAllergenList(corrected).pdf

 

 

Dermatologist Tulsa, OK

 

Call us today to set up an appointment 918.340.6539

11911 S. Oxford Ave Suite 200 • Tulsa 74137

Call us today to set up an appointment 918.340.6539

11911 S. Oxford Ave Suite 200 • Tulsa 74137