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: Jan 31, 2022
Last Updated On: Sep 19, 2023
Have you ever left an appointment with your dermatologist feeling confused by the medical jargon? You’re not alone. The language of eczema can be complex, full of precise terms that dermatologists learn in their training but don’t always explain to their patients.
To help you gain more confidence at the doctor’s office, we asked a board-certified dermatologist, Dr. JiaDe (Jeff) Yu, who works at Massachusetts General Hospital, to explain five key medical terms he often uses with his eczema patients.
If you have eczema, you may not know the word pruritus (proo-RIE-tus), but you’re probably all too familiar with what it describes — itch.
Itch is a major symptom of all seven types of eczema. It can keep people awake at night, trigger or worsen flares and lead to mental health difficulties such as irritability, depression and anxiety.
Recent research into the causes of pruritus may lead to new treatments in the near future. In the meantime, it can be managed in a number of ways, ranging from oatmeal baths to prescription medications. For more information on pruritus, and how to relieve it, check out our articles on “The Complex Science Behind Itch in Atopic Dermatitis” and “Managing Itch.”
According to Dr. Yu, lichenification (lai-ken-uh-fi-KAY-shuhn) “is a telltale sign for the dermatologist that the area has been itchy for a long time, and the patient has been scratching and itching for a long time.”
He explained, “It means the skin is thickened, to resemble lichen, due to chronic itching and scratching. The skin lines are accentuated, or deeper and more obvious than normal.”
Some people with lichenification may notice the thickened skin appears darker than usual.2 Sometimes small bumps (also known as papules) may appear.2
Lichenification is divided into two categories – primary and secondary.3 Primary lichenification is driven by chronically itchy patches of skin, usually in one or two areas of the body. This is also called neurodermatitis or lichen simplex chronicus.3 This condition can be triggered by stress, tight clothing, bug bites, nerve injury or dry skin.
Secondary lichenification is caused by an acute itch resulting from an underlying medical condition such as atopic dermatitis.3
Lichenification is treated by ending the itch-scratch cycle and healing the skin. Dermatologists may recommend treatments that can include topical corticosteroids, calcineurin inhibitors and ointments made with salicylic acid to control the itch. Some people have also found that going to counseling to manage anxiety, meditating or using cognitive-behavioral therapies can be useful.
An excoriation (ek-sko-ree-AY-shun) is a scratch or a wound caused by scratching or picking at the skin.
Although these lesions are relatively superficial, they can become problematic due to infection. “They can be portals of entry for bacteria such as Staphylococcus aureus that can infect over 80% of patients with atopic dermatitis,” said Dr. Yu.
Some ways to minimize excoriations are keeping your fingernails trimmed, or wearing gloves at times when you’re most likely to scratch, such as before sleep or while watching TV. Keeping your hands busy by doodling, squeezing a stress ball or using a “fidget” can also be helpful.
A fissure (FI-shr) is a linear crack in the skin. Dr. Yu said they “can occur due to dryness, inflammation and scratching.”
Dr. Yu noted that fissures can be painful. They are most common on the hands and feet.
NEA community member Sarah Harris shared her experiences with fissures. “My skin morphs into a desert-scape, dry and crackling. Fissures run like deep ravines at the creases of my knuckles, the corners of my lips, even behind my knees.”
To heal the fissures on her skin, Harris applies a thick moisturizer, then covers the affected area with cotton gloves or a bandage. These measures aid in repairing the skin barrier and preventing infection.
Flexure (FLEK-shur-al) means a bend or a curve. Flexural describes areas of the body that bend, like the backs of the knees (popliteal fossa), or elbow creases (antecubital fossa).
Dr. Yu explained that atopic dermatitis flares are common in these areas. Some dermatologists use the term “flexural eczema” interchangeably with “atopic dermatitis.”4
Flexural flares likely occur because salts from sweat build up in these areas, irritating the skin. Keeping these areas as dry as possible, especially in the summer, can help.
Research has shown that clear communication can improve the quality of doctor-patient relationships and help patients stay on their treatment plans.4
Dr. Yu also pointed out that understanding some medical terminology can support patients in keeping up-to-date on the latest developments in the field. He explained, “These terms are often used in the medical literature, on expert websites and in studies looking at medications for the treatment of atopic dermatitis. [Knowing them] can enhance the patient’s understanding of what’s going on in the world of atopic dermatitis from the clinician’s perspective.”
References
It’s often difficult to distinguish between nummular eczema and ringworm, so it’s always best to be evaluated by a dermatologist, say experts.
Karin Stoddart, 20, a college student from Seattle, finally has her eczema under control after battling with two insurance companies to stay on her doctor-prescribed medication.
Learn which plants won’t irritate your eczema — and can also help purify the air in your home.
Christina Crowley, from Berkeley, California, shares how she became a NEA board member — recently NEA’s Board Chair in 2023 — as well as a donor and Itching for a Cure fundraiser.
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