What is Nummular Eczema

Nummular eczema is a common disease that causes red, circular, crusted (plaque) lesions that may be itchy. It most commonly affects the lower legs and the backs of hands.

Men tend to get their first outbreak between 55 and 65 years of age, and women tend to get their first outbreak during their teen or young adult years.

What are the causes?

The cause of this condition is not known. It may be related to certain skin sensitivities, such as sensitivity to:

• Metals such as nickel and, rarely, mercury.
• Formaldehyde.
• Antibiotic medicine that is applied to the skin, such as neomycin.

What increases the risk?

You are more likely to develop this condition if:

• You have very dry skin.
• You live in a place with dry and cold weather.
• You have a personal or family history of eczema, asthma, or allergies.
• You drink alcohol.
• You have poor blood flow (circulation).

What are the signs or symptoms?

Symptoms most commonly affect the lower legs, but may also affect the hands, torso, arms, or feet. Symptoms include:

• Groups of tiny, red spots.
• Blister-like sores that leak fluid. These sores may grow together and form circular patches. After a long time, they may become crusty and then scaly.
• Well-defined patches of pink, red, or brown skin.
• Itchiness and burning, ranging from mild to severe. Itchiness may be worse at night and may cause trouble sleeping. Scratching lesions can cause bleeding.

How is this diagnosed?

This condition is diagnosed based on a physical exam and your medical history. Usually more tests are not needed, but you may need a swab test to check for skin infection. This test involves swabbing an affected area and testing the sample for bacteria (culture).

You may work with a health care provider who specializes in the skin (dermatologist) to help diagnose and treat this condition.

How is this treated?

There is no cure for this condition, but treatment can help relieve symptoms. Depending on how severe your symptoms are, your healthcare provider may suggest:

• Medicine applied to the skin to reduce swelling and irritation (topical corticosteroids).
• Medicine taken by mouth to reduce itching (oral antihistamines).
• Antibiotic medicine to take by mouth (oral antibiotic) or to apply to your skin (topical antibiotic), if you have a skin infection.
• Light therapy (phototherapy). This involves shining ultraviolet (UV) light on affected skin to reduce itchiness and inflammation.
• Soaking in a bath that contains a type of salt that dries out blisters (potassium permanganate soaks).

Follow these instructions at home:

Medicines

• Take over-the-counter and prescription medicines only as told by your health care provider.
• If you were prescribed an antibiotic, take or apply it as told by your health care provider. Do not stop using the antibiotic even if you start to feel better.

Skin Care

• Keep your fingernails short to avoid breaking open the skin when you scratch.
• Wash your hands with mild soap and water to avoid infection.
• Pat your skin dry after bathing or washing your hands. Avoid rubbing your skin.
• Keep your skin hydrated. To do this:
  • Avoid very hot water. Take lukewarm baths or showers.
  • Apply moisturizer within three minutes of bathing. This locks in moisture.
  • Use a humidifier when you have the heating or air conditioning on. This will add moisture to the air.
• Identify and avoid things that trigger symptoms or irritate your skin. Triggers may include taking long, hot showers or baths, or not using creams or ointments to moisturize. Certain soaps may also trigger this condition.

General instructions

• Dress in clothes made of cotton or cotton blends. Avoid wearing clothes with wool fabric.
• Avoid activities that may cause skin injury. Wear protective clothing when doing outdoor activities such as gardening or hiking. Cuts, scrapes, and insect bites can make symptoms worse.
• Keep all follow-up visits as told by your health care provider. This is important.

Contact a health care provider if:

• You develop a yellowish crust on an area of affected skin.
• You have symptoms that do not go away with treatment or home care methods.

Get help right away if:

• You have more redness, pain, pus, or swelling.

Summary

• Nummular eczema is a common disease that causes red, circular, crusted (plaque) lesions that may be itchy.
• The cause of this condition is not known. It may be related to certain skin sensitivities.
• Treatments may include medicines to reduce swelling and irritation, avoiding triggers, and keeping your skin hydrated.