What is Contact Dermatitis?
Contact dermatitis is a reaction that occurs when you touch or come in contact with certain substances (typically an allergen or irritant). When your skin comes into contact with substances that you’re allergic or sensitive to, it can become red, itchy, and irritated. These substances include certain chemicals present in skincare products, detergents, jewelry made of certain metals, and poison ivy. Contact dermatitis usually presents as a rash on your skin in the affected area. The protective layer of your skin gets damaged, dry, cracked, and forms blisters. Most reactions aren’t severe and can be easily managed or treated completely.
Symptoms of Contact Dermatitis
The general symptoms include:
- Swelling
- Redness
- Skin irritation
- Bumps, blisters (rarely)
- Itching or burning
- Tender skin
The symptoms can vary based on the type of contact dermatitis. They can be mild or severe and can appear immediately on contact or a few days later. Contact dermatitis is not contagious. The hands are known to be the most common part affected by contact dermatitis.
Types of Contact Dermatitis
- Allergic contact dermatitis - An allergic reaction develops on contact with allergens like poison oak or poison ivy, latex, jewelry made of certain metals, and chemicals in cosmetic products.
- Irritant contact dermatitis - This is the most common type of contact dermatitis, that occurs when the skin comes into contact with toxic substances like bleach, detergents, or battery chemicals. People whose hands are frequently exposed to water or soap also experience irritant contact dermatitis.
- Phytophotodermatitis - This is the least common type of contact dermatitis, that occurs when your skin comes in contact with certain plant chemicals. These chemicals on exposure to sunlight get activated and cause skin reactions.
The Genetics Behind Contact Dermatitis
Variations in certain genes are found to increase a person’s risk of contact dermatitis. The risk for contact dermatitis runs in families. It can be passed down through generations. Research is still being done to establish further relations between genetics and contact dermatitis.
TNF Gene
The TNF gene encodes the Tumor Necrosis Factor, which is a proinflammatory cytokine found in immune cells. This is mainly involved in the chronic inflammation process in the body. This gene has been implicated in various conditions like asthma, heart disease, and liver disease.
Repeated exposure to allergens leads to inflammation of the skin. This is called the elicitation phase. TNF plays an important role in this phase of allergic contact dermatitis.
rs1800629
rs1800629 is an SNP found in the TNF gene. The A allele leads to increased production of TNF and a higher risk of developing allergic contact dermatitis compared to the G allele, which is the major allele.
rs361525
This SNP is also found in the TNF gene. Individuals with the A allele are less prone to develop dermatitis of the hands, suggesting a protective effect of the A allele.
Non-genetic Factors That Influence Contact Dermatitis
- Increased exposure to plants like poison ivy while trekking or hiking and other substances in a garden.
- Occupational contact dermatitis is common in various professions that involve handling substances like chemicals.
- People who work around chemicals every day in a factory are at increased risk of developing contact dermatitis.
- Healthcare professionals are at a higher risk of developing a latex allergy.
- Beauticians and hairdressers are exposed to chemicals in skincare products that can cause a reaction.
- Construction workers are also exposed to chemical substances like epoxy resin that can trigger a reaction.
How to Manage Contact Dermatitis?
Home Remedies
- Try to determine the trigger. It may be a new skincare product that you’re using or some plant that you touched, or even certain jewelry. Avoid contact with these products in the future.
- Wear long sleeves and full pants while hiking to prevent contact with potential irritants in plants.
- On contact with an allergen or irritant, wash your skin with mild soap and cold water immediately.
- Use products that are hypoallergenic or unscented.
- The irritated skin can be treated using hydrocortisone cream.
- Moisturizers can also be used to heal the damaged skin and restore the protective layer.
- Blisters can be treated with a cold, moist compress for 30 minutes, three times a day.
- Oral antihistamines can help with allergic reactions.
Finding Potential Triggers
If you have sensitive skin, do a patch test or spot test before using any new product. A patch containing the product or the product itself is applied on a spot in the forearm and covered. Avoid using water or soap near the spot for 48 - 96 hours. If there’s any reaction like redness or itching, the product contains a potential allergen or irritant and should be avoided.
In Cases Of Severe Reaction
- Talk to a healthcare professional when your symptoms are severe and do not respond to any home remedies. They will be able to point out a cause and recommend further treatment.
- Depending on how severe your symptoms are, the doctor will prescribe antihistamine creams, steroid pills, or immunosuppressive agents.
Summary
- Contact dermatitis is a reaction on the skin that causes redness, itching, and irritation on contact with certain substances. These substances include certain chemicals, poison ivy, metals, detergents, and cosmetic products.
- The symptoms include rashes, itching, irritated skin, blisters, and dryness. The types of contact dermatitis include allergic, irritant, and phytophotodermatitis.
- Genes play a role in increasing your risk of contact dermatitis. The A allele of rs61816761, an SNP found in the FLG gene, increases the risk of contact dermatitis and other skin allergies. The A allele of rs1800629, an SNP found in the TNF gene, also increases your risk of allergic contact dermatitis.
- People who work in the construction industry, beauty industry, and healthcare industry increase their exposure to allergens and irritants.
- Contact dermatitis can be managed by finding the trigger and avoiding further contact. Certain home remedies can help treat the condition fully. In severe cases, a healthcare professional should be consulted.
References
https://www.healthline.com/health/contact-dermatitis#symptoms
https://www.webmd.com/skin-problems-and-treatments/contact-dermatitis#2
https://www.ncbi.nlm.nih.gov/pubmed/28300283
https://www.verywellhealth.com/contact-dermatitis-causes-83205
https://www.snpedia.com/index.php/Rs1800629
https://pubmed.ncbi.nlm.nih.gov/18620134/
https://www.ncbi.nlm.nih.gov/gene/2312
https://pubmed.ncbi.nlm.nih.gov/23374260/
https://www.snpedia.com/index.php/Rs61816761
https://onlinelibrary.wiley.com/doi/abs/10.1111/cod.12362
