Discoid Eczema

Discoid eczema, also known as nummular eczema, is an inflammatory condition that causes raised, oval-shaped rashes on the skin. Researchers aren’t sure of this skin disease’s causes, but it commonly affects middle-aged adults. A family history of conditions like eczema (atopic dermatitis) or asthma are among the factors that increase your odds of developing it. Studies have found between 0.1-9.1% of the population experience discoid eczema.

Discoid eczema symptoms can vary in severity depending on the underlying cause and individual case. Some people have chronic itchy, rashes, while others go through periods of active symptoms and remission. Treatments for the condition depend on the pattern of your symptoms and how often you experience them. That said, there are many options for easing the symptoms of discoid eczema and preventing attacks.

Discoid Eczema Symptoms 

Though individual cases vary, the rashes that form due to discoid eczema have a distinctive round shape. This disease goes through periods of activity, which can last from several weeks to months, as well as periods of remission (recovery). Discoid eczema typically has several phases, though certain symptoms may persist between flare-ups. It most often appears on the legs, arms, or tops of the hands.

Early Symptoms

Small, itchy bumps, or papules, are the first sign of discoid eczema. These are often accompanied by small blisters, fluid-filled sacs on the skin. The papules release fluid and start to form a crust.

Discoid Plaques

After crusting over, the papules join together to form plaques—raised discolored areas of irritated skin. Round or oval in shape, these can range from less than 0.5 inches to four inches in diameter. If you have darker pigmentation, the plaques are brown. If you have lighter pigmentation, they’re red or pink.  

These plaques cause severe itching, which can worsen at night or when you’re trying to sleep or relax. Affected areas may burn or sting. Wider patches of dry skin can develop between the growths.

Late Symptoms

The circular plaques flatten as they subside, and the centers clear up first. When gone completely, there may be a flat spot of different-colored skin, something more common if you have darker pigmentation. Repeated flare-ups can cause raised areas of discolored skin.

What Causes Discoid Eczema? 

Discoid eczema is an inflammatory (immune-related) reaction that leads to an overproduction of skin cells. Papules, lesions, and plaques form due to these excess cells. Researchers aren’t sure why this happens but believe it’s linked to problems with the lipid barrie—a layer of amino acids and oils that help keep moisture in the skin.

In many cases, discoid eczema flares occur due to certain environmental or health triggers. These include:

• Injuries or insect bites
• Stress
• Dry, hot, or humid air
• Bacterial or viral infection
• Certain metals (in those who are allergic), often nickel
• Certain make-up, fragrances, or other products
• Some medications, including statins (drugs used to lower cholesterol) and diuretics (drugs that remove excess fluid from your body)
• Excessive alcohol use

Risk Factors

While all people can develop discoid eczema, some are at increased risk. Risk factors for this condition include:

• Age: Rare in children, discoid eczema is most prevalent in people assigned female at birth between 15-25 and people assigned male at birth over 50 years old.
• Eczema: Common eczema (atopic dermatitis) causes patches of dry, flaky, scaly, and irritated skin.
• Family history of allergy: Having a relative with allergies, asthma (a chronic lung disease that causes airways to become inflamed and narrowed), or eczema raises the risk.
• Poor circulation: Blood circulation conditions causing blood to pool in the legs, such as deep vein thrombosis, or DVT (a blood clot), can cause skin symptoms.
• Contact dermatitis: This is an allergic skin reaction triggered by contact with certain substances, often fragrances or metals like nickel.

Diagnosis 

If you present with discoid eczema symptoms, your healthcare provider will need to rule out other potential causes of symptoms. Many other conditions can cause disc-shaped rashes, including chronic skin conditions like plaque psoriasis (an autoimmune skin condition) and stasis dermatitis (skin symptoms due to poor circulation), cancer, and fungal growth (tinea corporis).

In addition to assessing your medical history and status to determine risk, healthcare providers may perform the following diagnostic tests:

• Physical assessment: Healthcare providers visually evaluate affected areas and take note of their size, shape, and characteristics.
• Dermoscopic evaluation: Healthcare providers look at affected areas under a specialized microscope.
• Culture testing: The provider swabs a plaque and tests it for signs of bacterial infection.
• Allergy testing: If they suspect contact dermatitis, healthcare providers introduce small amounts of allergens to the skin and observe the reaction.
• Biopsy: Clinical testing of skin samples helps healthcare providers detect a wide range of skin conditions.
• Potassium hydroxide test: Applying potassium hydroxide to a scraping of skin under a microscope detects signs of fungal infection that may cause symptoms.

Discoid Eczema Treatment 

Discoid eczema is often treated by a dermatologist (a medical doctor specializing in skin, hair, and nail conditions) or an allergist. Healthcare providers primarily work to ease symptoms and reduce the frequency of attacks. They tailor therapies to individual cases. Medications, home therapies, and lifestyle changes all potentially play a role.

Medications

Topical and oral medications provide relief from symptoms and treat complications. These include:

• Corticosteroid (steroid) creams, such as Cortisone (hydrocortisone) or Luxiq (betamethasone)
• Topical calcineurin inhibitors like Protopic (tacrolimus) and Elidel (pimecrolimus)
• Oral antihistamines like Allegra (fexofenadine) or Claritin (loratadine) to help reduce symptoms at night
• Antibiotics to treat infections or complications
• Monoclonal antibodies like Dupixent (dupilumab), an emerging treatment

Home Remedies

Promoting healthier skin and restoring its ability to retain moisture are the main aims of home management. Applying emollients (moisturizing creams) such as petroleum jelly to the skin one or more times a day is a first-line approach. Your provider may also recommend you take shorter, lukewarm showers or baths. Hot temperatures can trigger flares.

Trigger Avoidance

Trigger avoidance—avoiding identified triggers of symptoms—prevents outbreaks of discoid eczema. Potential triggers of this condition include:

• Certain fragrances in beauty and cosmetic products, perfumes, and soaps
• Dryer sheets or laundry detergents with fragrances
• Poison ivy or poison oak
• Dry air indoors due to air conditioning or heating
• Certain fabrics or wools, especially on tight-fitting clothing
• Nickel or other metals

Phototherapy

In difficult-to-manage cases, phototherapy (light therapy) involves directing ultraviolet B (UVB) rays to affected areas from specialized lamps. These rays reduce the inflammatory response that causes discoid eczema, helping to clear up attacks.

Prevention

Since discoid eczema is a chronic condition, prevention strategies work to minimize flare-ups and promote healthier skin. Several strategies help:

• Choose gentle skincare: Apply fragrance-free, hypoallergenic moisturizers at least once daily to help retain moisture in the skin
• Bath mindfully: Don’t take baths or showers longer than 20 minutes, use lukewarm water and gentle soaps, and moisturize after bathing
• Use humidifiers: Use a humidifier, especially during drier seasons
• Avoid heat: Keep your home cool and be careful not to sit too close to fireplaces or heaters
• Protect your skin: Wear gloves or clothing that protect you from injuries, bites, or substances that trigger attacks
• Manage stress: Try meditation, yoga, exercises, or relaxing activities
• Wear loose-fitting clothing: Wear looser clothing with breathable and gentle fabrics, such as cotton, to prevent skin irritation
• Choose natural fabrics: Avoid potential allergens, such as wool, polyester, rayon, and others
• Limit alcohol: Reduce or avoid alcohol

Related Conditions

Discoid eczema is a chronic and recurrent condition, and it can raise your risk of complications and other conditions. These include:

• Infection: Scratching discoid eczema plaques can cause open sores and bleeding, allowing bacteria or other pathogens to enter and infect your skin. Yellow or golden-colored fluid oozes and forms crusts on affected areas.
• Scarring: Over time, infections and damage to the skin can cause permanent scarring and permanent discoloration in affected areas.
• Depression: Living with eczema can lead to depression. More severe skin symptoms can lead to more severe symptoms.
• Anxiety: Anxiety disorders, which often accompany depression, can also arise due to the effect eczema can have on physical appearance and sleep.

Living With Discoid Eczema

While discoid eczema isn’t fatal, living with a chronic skin condition can significantly affect your quality of life. Medical therapies, home remedies, and lifestyle choices can minimize symptoms, along with medical treatment. The key is to remain proactive. Track your progress, including what is and is not helping with symptoms.

If you’re struggling with mental health, individual or group sessions with a mental health counselor, psychiatrist, or psychologist may be valuable. You may also find in-person or online support groups helpful or social media groups devoted to chronic skin diseases. In addition, advocacy organizations, such as the National Eczema Society or the National Eczema Association, can be sources of information and support.