What Conditions Can Mimic Eczema?

Eczema is a common skin condition that’s often hard to diagnose. The signature symptoms, including dry skin, rashes, itchiness, scaly patches, and blisters, can look like other skin problems.

There are seven subtypes of eczema, each with specific characteristics that set them apart. Eczema is commonly mistaken for other skin conditions, and sometimes, those other problems are misdiagnosed as eczema.

This article discusses skin conditions frequently confused with eczema and how you can tell them apart.

Conditions That Mimic Eczema 

Some skin conditions that may mimic eczema include:

• Ringworm
• Psoriasis
• Allergic contact dermatitis
• Polymorphous light eruption (PMLE)
• Skin infections
• Skin lymphoma
• Lupus
• Acne
• Rosacea

Ringworm

Ringworm is a skin infection caused by a fungus. It appears in the shape of a ring and is usually itchy and red. Ringworm can affect the skin on almost any body part, including the fingernails and toenails, and typically responds well to anti-fungal treatments.

Psoriasis

Psoriasis is an immune-related skin disease that causes itchy rashes and scaly patches, much like eczema. Both psoriasis and eczema can appear anywhere on the body, but psoriasis is more likely to develop on the:

• Scalp
• Elbows
• Knees
• Buttocks
• Face

Eczema can occur in those places too, but often affects the back of the knees or the inside of the elbows. You can get either condition at any time, but eczema tends to affect children, while psoriasis usually develops in adulthood.

Ultraviolet B (UVB) light from the sun can ease symptoms of psoriasis and certain types of eczema.

Allergic Contact Dermatitis

Allergic contact dermatitis (ACD) is a rash caused by an immune reaction to certain substances that touch the skin. It often occurs along with eczema. ACD is caused by a reaction to allergens, such as: 

• Nickel and other metals
• Shampoos, cleansers, moisturizers, or deodorants
• Cosmetics, hair dye, or nail polish
• Topical medicines
• Plants
• Rubber
• Plastics and glues

An ACD rash causes itchy, red, and flaky skin that sometimes blisters or oozes. It may take hours or days to appear after exposure to the problematic substance, and it could take weeks to heal.

Eczema is usually found on the face, elbows, feet, skin creases, and backs of the knees, while ACD can crop up wherever you are exposed to an irritant.

Polymorphous Light Eruption (PMLE)

Polymorphous light eruption (PMLE) causes an itchy rash triggered by sunlight. The rash typically occurs on the face, forearms, backs of the hands, and neck. The symptoms usually appear within several hours of sun exposure and can last up to two weeks. 

The condition usually occurs during the spring or summer when people are more likely to be outdoors.

Bacterial Skin Infections

Skin infections may sometimes be mistaken for eczema. Typically, skin infections caused by bacteria, such as staphylococcus, appear red, hot, and swollen. Additionally, they may contain pus or ooze a honey-colored crust.  

These skin infections may also accompany other symptoms, such as a fever. They usually respond to topical or oral antibiotics.

Skin Lymphoma

Skin (cutaneous) lymphoma is a rare skin cancer not linked to sun exposure. Typically, skin lymphoma appears as:

• Small, pimple-like lesions
• Plaques (patchy, flat lesions)
• Bumps under the skin

Like eczema, lesions can be itchy and scaly. They are usually red or purple and appear on areas of the skin that aren’t exposed to sunlight. People with skin lymphoma may also experience fatigue, high white blood cell counts, and enlarged lymph nodes.

Lupus

Lupus is an autoimmune disease that affects many organs in the body, including the skin. One common symptom of lupus is a butterfly-shaped rash that usually appears on the cheeks and nose. Other symptoms of lupus include:

• Joint pain
• Fatigue
• Skin lesions that often worsen when exposed to sunlight
  
• Dry eyes

Acne

Acne happens when hair follicles become clogged with oil and dead skin cells. Symptoms of acne include raised whiteheads, blackheads, or pimples. The lesions usually appear on the face, forehead, chest, back, and shoulders.

Although acne can look like eczema, it isn’t itchy. Acne tends to crop up in oily areas of the skin, while eczema usually affects dry areas.

Rosacea

Rosacea is a skin condition that causes small blood vessels in a person’s face to swell, which results in flushing. It can also trigger small, pus-filled bumps to form, which may be mistaken for eczema.

Rosacea is most likely to affect the cheeks, nose, eyelids, forehead, and skin around the mouth.

How to Properly Diagnose Eczema

Healthcare providers typically diagnose eczema by observing your skin and asking about your symptoms. To rule out other conditions, they may have to perform tests.

A patch test can help determine if you have allergies. A biopsy can reveal important information, such as whether eczema is present in your skin cells. Additionally, it can let your healthcare provider know if your skin lesions are cancerous or benign.

Summary

Eczema is a common skin condition that's frequently misdiagnosed. Symptoms of eczema, which include an itchy, scaly, and red rash, can mimic that of other problems. Knowing the classic signs can help determine if it's eczema or something else.

Your healthcare provider may have to perform special tests to confirm that your skin symptoms are caused by eczema. Once a diagnosis is confirmed, treatments can help keep your symptoms at bay.