Allergic Contact Dermatitis and Patch Testing

Allergic Contact Dermatitis and Patch Testing

Have you ever had an itchy rash that is so uncomfortable it can disturb your sleep? Is this rash persistent or does it come and go, with repetitive outbreaks? Does your rash last for days, weeks, or months? If your answer is yes to one or more of those questions, there is a decent chance that you have allergic contact dermatitis. Allergic contact dermatitis is exceedingly common—virtually every person will have at least one episode of this rash during their lifetime. Some of us are affected more severely than others.

Allergic Contact Dermatitis and Patch Testing

Allergic contact dermatitis is a skin rash that develops because of an allergic reaction. This is triggered by our immune system due to chemicals contacting the skin. We live in a world full of chemicals where virtually everything we use on our skin contains chemical ingredients. We can even become allergic to many natural/organic chemicals that we have contact with. Certainly, most of us will never become allergic to most chemicals that are out there. Some of these are more likely culprits than others when allergic contact dermatitis develops. That includes anything from your clothing to your shampoo to your make-up, from things that you come in to contact with at home, at play, and at work. That said, so far science has identified more than 4,000 chemicals that can trigger a skin rash!

Symptoms of Allergic Contact Dermatitis

The rash itself can have a specific appearance based on how long it has been present. For those of us with sudden onset allergic contact dermatitis, we usually have itchy red patches and bumps sometimes with blisters. If the allergic contact dermatitis has been there longer, the appearance may be more of thickened areas of skin that are scaly but lack blisters. From your head to your toes and everywhere in between, the rash may show up in any area of the body. Furthermore, some cases are widespread, affecting many areas on our skin. However, most cases are usually localized.

Common Causes of ACD

Of those 4,000 ingredient chemicals that have been identified as causing allergic contact dermatitis, some are much more frequent offenders in general. The sap contained within the plant poison ivy is the absolute most classic example. Remember the adage, “leaves of three let them be.” This plant is a frequent cause of allergic contact dermatitis in the patients that we see in our clinics. In most cases, we can identify a specific rash due to poison ivy. This is based on its streaky appearance and a person’s history. Usually, they will tell us that they have been out in the woods or doing yard work. That is to say, they were in an area where they may have been exposed to plants contacting their skin.

As with other forms of allergic contact dermatitis, the time between the exposure to the chemical and the rash developing is usually delayed by 3 to 7 days. Because of this, this type of allergic reaction is referred to as delayed-type hypersensitivity.

Patch Testing

It may be possible in some cases for the best dermatologists to make an educated as to the identity of the causative chemical. However, the only way to conclusively prove the cause of allergic contact dermatitis is to do a simple allergy test known as patch testing.

Patch testing is generally a five-day test. It involves putting the most common chemical ingredients on a patient’s skin to see if they will cause a rash. Keep in mind, this type of testing is distinct from the more common type of skin allergy testing. In contrast, patch testing is painless and simply involves placing small patches on the skin which contain the chemical allergens. Firstly, the patches are usually placed on Monday. Secondly, they are removed on a Wednesday, at which time the initial test result reading is recorded. Lastly, the final test readings are taken in follow up on Friday of the same week.

These test readings involve identifying if there is a rash in the localized area. Test readings also grade the intensity of the reaction/rash. In our clinic, we test the 65 most common chemical allergens which are known to cause allergic contact dermatitis. The testing is considered medically necessary if a person has suffered from issues from their allergic contact dermatitis for longer than six weeks.

Allergic Contact Dermatitis CAMP Database

In cases where patch testing identifies positive reactions, we can assist our patients in avoiding chemical allergens. Thus, helping their dermatitis to improve over time along with active treatment specifically for the rash. First, we provide each patient with detailed information regarding exactly what chemicals they reacted to. Also, we note where these chemical ingredients frequently occur, whether either in nature or in certain products. Second and most importantly, we enter all the allergens into a special database known as the C.A.M.P. Database. This stands for Contact Allergen Management Program. This step is what is most critical and what makes our clinical approach at Advanced Dermatology of the Midlands so effective for our patients.

The American Contact Dermatitis Society manages this database, which runs a highly detailed computer algorithm. It searches products by category and creates a list of products that are safe for patients to use with allergies. Conveniently, this list breaks safe-to-use products down into different categories. Categories such as moisturizer, shampoo, soap, makeup products, sunscreen, etc.…. The American Contact Dermatitis Society has also created a shopping app that patients can use. Patients may utilize their list so that they can specifically reference when they are in the store purchasing products.

Allergic Contact Dermatitis Treatment Omaha

The allergies causing allergic contact dermatitis are lifelong allergies. Medical science has yet to give us a way to reliably desensitize a person to these allergies so that they can tolerate exposure to them in the future without any difficulties. However, with the use of the resources above and active treatment of any rash present, patients can do extremely well. Despite having allergies, patients go on to have a completely normal life.

We hope you find this basic background information on allergic contact dermatitis and patch testing helpful. If you or someone you care about may have allergic contact dermatitis, please consider contacting us to schedule a dermatology consultation with any of our exceptional dermatology providers. Also, look forward to our upcoming blog in the next few weeks about treatment for allergic contact dermatitis and similar conditions.

Advanced Dermatology of the Midlands | Best Dermatologist Omaha & Council Bluffs, IA | Board Certified Dermatologists

If you are interested in pursuing this wonderful skin treatment or want to find out more information, please contact us at (402) 933 3770.  We offer this treatment in all our offices at 129th and Pacific (Sterling Ridge) and 15805 West Maple in Omaha and Valley View Drive in Council Bluffs. If you need more assistance, please consider seeing us in a consultation.