Discoid eczema, also known as Discoid dermatitis, Nummular dermatitis or Nummular eczema can be defined as a long-term skin-inflammation that is quite uncomfortable and itchy in nature. The word “nummular” comes from the Latin word “nummulus,” meaning a coin since the infection usually appears in the form of red coin-shaped discs, or plaques of eczema. There might be a singular patch or several patches throughout the body.

Although discoid eczema is not contagious, it can be chronic and can be recurrent and long-term in nature. While the plaques don’t appear on the face and scalp, it may be found on different parts of the body, mostly the forearms, lower legs, hands, and sometimes even the trunk. These patches can be a few millimetres to a few centimetres in size and are more likely to appear in women than in men in their 50’s and 60’s.

Causes

Although the absolute cause of this type of eczema is yet unknown, many pieces of research show that the discoid eczema is more common in people who have dry, sensitive skin that is easily irritated by external allergens like creams, ointments, soaps, detergents, and rough clothing. This shows that contact dermatitis which occurs when people come into direct contact with the allergens play a critical role in the case of discoid eczema. Even people who have a history of atopic eczema or have been diagnosed with or are prone to asthma or hay fever are more likely to get discoid eczema. Also Read: Contact Dermatitis: Causes, Symptoms and Treatment

Triggers That Cause Discoid Eczema

Discoid Eczema can also get triggered due to the following conditions:

• A minor skin injury like a burn or an insect bite
• A side effect of medications used for treating hepatitis C, arthritis or other skin allergies
• Dry, damp weather with low humidity levels

Symptoms

The initial signs of discoid eczema usually appear in the form of small red spots or bumps on the skin that slowly join together to form larger pink, reddish-brown patches that can range from a few millimetres to several centimetres in size. Other common signs and symptoms include:

• Swollen patches
• Blisters around the patch, oozing out pus
• Inflammation and itching around the patch

Complications

With passing time, these blisters might dry up to form dry, scaly patches with a clear centre often representing a ringworm infection. Also Read: Ringworm: Causes, Symptoms And Treatment

If these patches are not treated on time, this form of eczema can last for weeks, months or years or even keep recurring and leave behind permanently discoloured skin. Occasionally, if left untreated discoid eczema can also get infected and cause:

• Yellow crust developing over the patches
• The skin around the patches becoming red, hot, tender or swollen, 
• Fatigue 
• Feeling sick
• Mild fever and chills

Diagnosis And Treatment

If you notice any of the above-mentioned signs and symptoms, make a note to consult a doctor right away to start the treatment at the earliest and prevent eczema from recurring or getting infected. The doctor usually does a thorough checkup and acknowledges the patients past medical history followed by a skin test to rule out other forms of infection.

Treatment

Treatment options usually consist of:

• Topical corticosteroids in the form of creams and ointments to relieve the skin of chronic symptoms. 
• Medications like antihistamines to improve sleep quality and reduce itching and inflammation of the skin.
• Topical emollients in the form of moisturisers to reduce drying and moisturise and nourish the affected skin.

It should be kept in mind to avoid using any kind of skin irritants like soaps, shower gels, makeup products or other chemical body washes during the specified period of treatment to avoid escalation of the infection.