How to Tell the Difference Between Nummular Eczema and Ringworm
It’s often difficult to distinguish between nummular eczema and ringworm, so it’s always best to be evaluated by a dermatologist, say experts.
Published On: Jul 7, 2017
Last Updated On: Jul 15, 2021
Whether you’re newly diagnosed or have been afflicted for years, there are always opportunities to expand your knowledge base about eczema. That’s because there is so much more to learn.
Scientists are constantly making new discoveries about the underlying causes and triggers of eczema. Not only does this allow them to develop safer and more effective treatments, it brings us one step closer to a cure.
But it’s not just the scientists and doctors who should be staying up to date on all the latest research. You owe it to yourself as the patient to take responsibility for your health. The more you know about the inner workings of eczema, the easier it will be to spot symptom triggers and make well-informed decisions about your treatment options.
Eczema is a group of medical conditions that cause the skin to become itchy, inflamed or irritated. The most common type of eczema is atopic dermatitis (AD), which usually starts in infancy and can continue into adulthood. However, it’s possible for some people to develop AD later in life.
The word “atopic” refers to a hyperactive immune response, while “dermatitis” means inflammation of the skin. While we don’t know the root cause of AD, researchers suspect a combination of genetics and environmental factors are involved, and that it’s spurred by an overactive immune system.
When something from outside the body triggers the immune system, the skin cells don’t behave like they should, causing the skin to flare up. We also know that people who come from families with a history of AD, asthma or hay fever are 50 % more likely to develop AD themselves, highlighting the importance of genetics.
If you have any form of eczema, take comfort in knowing you are not alone. More than 30 million people in the U.S. have some form of it, be it atopic dermatitis or:
Contact dermatitis (CD)When your skin comes into contact with a substance that you are either allergic to, such as a fragrance or household chemical, or a substance that is irritating to anyone who comes into contact with it, such as solvents or acids, this might create a dry, itchy, scaly rash. The most common types of CD are allergic and irritant.
Also known as prurigo nodularis, LSC is an itchy skin disease which can result from any form of eczema due to too much rubbing or scratching of the area.
Both genetics and contact with allergens or irritating chemicals are the culprits behind this type of eczema, characterized by itchy, blistering, or dry, cracking skin on the hands.
This rash of itchy blisters appear on the edges of the fingers, toes, palms and soles of the feet. It can be caused by stress, seasonal allergies or exposure to chemicals or other substances, and is twice as common in women as it is in men.
Also known as discoid eczema or nummular dermatitis, this type of eczema appears as itchy, coin-shaped spots and can strike at any age. It looks very different than the usual eczema and can be much more difficult to treat.
This type of eczema is sometimes called venous stasis dermatitis because it usually occurs where there is a problem with blood flow in the veins. Pressure develops, usually in the lower legs, causing fluid to leak out of the veins and into the skin.
The word “eczema” is derived from the Greek word “ekzein” meaning “to boil over”, which is an apt description for the red, inflamed, itchy patches that drive us nuts.
“One patient put it in good terms when they said, ‘If you get a bug bite and that drives you crazy because you are itching, imagine a thousand bug bites on your body.’ For those with eczema, that is the equivalent,” said Dr. Paul Yamauchi, a dermatologist in private practice at the Dermatology Institute and Skin Care Center in Santa Monica, California.
“Imagine a thousand bug bites on your body.”
Yamauchi is on staff at St. John’s Health Center in Santa Monica, the University of California, Los Angeles (UCLA) Medical Center in Santa Monica and the Ronald Reagan UCLA Medical Center in Westwood, California. He’s also clinical assistant professor of medicine in the Division of Dermatology at the David Ge en School of Medicine at UCLA and adjunct associate professor at the John Wayne Cancer Institute in Santa Monica.
Sometimes the itch gets so bad you scratch it until it bleeds, which can make your eczema worse. This is called the “itch-scratch cycle.” “When your skin itches, that causes inflammation, which causes your skin to itch again.
This cycle of itching and scratching is what leads to the flaring of eczema,” said Dr. Jonathan Spergel, professor of pediatrics at the Children’s Hospital of Philadelphia and Perelman School of Medicine at the University of Pennsylvania. He specializes in atopic dermatitis, allergies and asthma in children.
Avoid entering the itch-scratch cycle at all costs. Scratching will break the barrier of the skin and increase your chances of developing a staph infection.
Although everyone is colonized with Staphylococcus aureus or staph—which means the bacteria is present but not causing an infection— those with eczema have been found to have greater amounts.
While most staph infections are minor and can be treated with antibiotics, staph bacteria can sometimes lead to life-threatening infections.
Opt for a thick cream or ointment like petroleum jelly and apply it liberally to damp skin at least twice a day to prevent the skin from drying and cracking. It can also be helpful to apply moisturizer and then drape wet towels over it to hydrate the skin.
Keep your nails short and wear gloves at night to avoid scratching yourself in your sleep. Put cold compresses on areas for a short time to numb the skin. Some people find oatmeal baths to be helpful.
The best way to replace moisture in the skin is to soak in a bath or take a shower and then moisturize immediately afterward. Soaking in a tub of lukewarm (not hot) water can help your skin better absorb moisture, but bathing is also very relaxing and can help ease stress. Just remember not to soak longer than 10 to 15 minutes and avoid scrubbing your skin with a washcloth or loofah.
Look for moisturizers, detergents and cleansers with NEA’s Seal of Acceptance™ on the label. Products that receive the Seal of Acceptance™ are intended for use by persons with eczema or severe sensitive skin conditions.
Read: An old treatment approach offers new option to patients with atopic dermatitis
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