Both eczema and ringworm can cause an itchy, red rash that appears in circular shapes. The rash may blister or be made up of tiny bumps. It can spread and may become dry and scaly. Even doctors can mistake eczema for ringworm, and since the treatments are very different, it's important to differentiate accurately before treating. The best test is to scrape the infected skin and have it examined for fungus.
Causes and Contagion
Ringworm is a contagious infection while eczema is not.
Ringworm spreads through direct or indirect contact with a group of fungi known as Dermatophytes. Trichophyton and Microsporum are the two most common fungi that cause ringworm, according to Dr. William Spears. You can catch ringworm by touching an infected animal or person, touching an infected person's clothing or towel or by touching something an infected animal rubs against. You can also get ringworm from soil, reports Charlottesville Dermatology.
Nummular or discoid eczema is the type of atopic dermatitis that appears in circular patches, so it's the type most likely to resemble ringworm. People who develop eczema usually have an inherited tendency to develop allergic conditions. Stress and environmental triggers can cause eczema to develop, but eczema can also occur for no known reason. Irritants such as frequent bathing, harsh soaps and wool clothing can cause nummular eczema to flare up.
Eczema starts with an itchy area of skin. Scratching causes the area to redden and swell. The skin may crack and weep a clear fluid. Then the area becomes crusty and scaly. Nummular eczema can appear as a dry patch about the size and shape of a coin.
Ringworm rashes appear as circular lesions with raised borders. The border may consist of bumps, blisters or scales. As the fungus spreads, the center area of skin heals and appears clear and almost normal. The red ring is common in ringworm, but not all ringworm rashes appear this way reports, Dr. Alan Greene. Ringworm rashes can look very different from one case to another. The circular, raised areas may also merge together in large patches.
Who Gets It?
Ringworm is common in young children, and boys get ringworm more easily than girls, reports Dr. Greene. People with eczema are prone to ringworm and other infections because their skin is often cracked and vulnerable.
Nummular eczema is most common in middle-aged men, according to New Medical Information and Health Information.
Both eczema and ringworm can affect people of any age or sex.
Another way to tell the difference between eczema and ringworm is to determine which treatment is effective. Ringworm will usually clear up with an antifungal medication within 7 to 10 days. If the rash does not clear up after 4 weeks, it's probably not ringworm, according to Dr. Greene.
Hydrocortisone can help stop the itch that comes with eczema, but it won't help you stop scratching a ringworm infection. Steroid creams can worsen a ringworm rash, according to pediatrician Jennifer Shu. Eczema improves when treated with alcohol-free moisturizers and steroid creams.
Eczema is usually a chronic and recurring condition, but, in some instances, people have only one episode of the rash. Ringworm may disappear on its own in a matter of months, but the rashes can become chronic.