Abnormal Appearing Skin: Skin Abnormalities Explained

What "skin abnormalities" means

Doctors use the term skin lesion for any area of skin that looks different from the skin around it. "Abnormal appearing skin" is a broad, descriptive phrase rather than a diagnosis. To narrow it down, a doctor describes what they see using standard terms:

Noting which of these you have, where it is, whether it itches or hurts, and how quickly it appeared is the most useful information you can bring to an appointment.

Common causes of skin abnormalities

Inflammation and irritation

• Eczema (atopic dermatitis): dry, itchy, red patches, often in elbow and knee creases, that come and go.
• Contact dermatitis: an itchy or burning rash where skin touched an irritant or allergen such as nickel, fragrance or poison ivy.
• Psoriasis: well-defined, thick, red plaques with silvery scale on elbows, knees, scalp and lower back.
• Seborrheic dermatitis: greasy yellow scale on the scalp (dandruff), eyebrows and sides of the nose.
• Rosacea: facial flushing, persistent redness and pimple-like bumps on the cheeks and nose.
• Hives: itchy raised welts that move around and fade within 24 hours.

Infections

• Bacterial: impetigo (honey-colored crusts), cellulitis (spreading red, hot skin), boils.
• Viral: warts, cold sores, shingles, chickenpox and viral rashes with fever.
• Fungal: ringworm (a ring with a scaly edge and clearer center), athlete's foot, yeast in skin folds.
• Parasites: scabies (intense night-time itch with tiny burrows between the fingers).

Growths and spots

• Benign growths: moles, skin tags, seborrheic keratoses, cherry angiomas, cysts and lipomas.
• Sun damage: freckles, age spots and rough actinic keratoses, which can become cancerous.
• Skin cancer: basal cell carcinoma (pearly bump that bleeds), squamous cell carcinoma (scaly, crusted or growing lump) and melanoma (changing or irregular mole).

Color changes

• Darker skin: post-inflammatory marks, melasma, and hyperpigmentation from medicines or hormones.
• Lighter skin: vitiligo, fungal infection (pityriasis versicolor), and scarring.
• Yellow: jaundice from liver or blood problems.
• Pale or blue: anemia, poor circulation or low oxygen.

Skin abnormalities that point to internal disease

Sometimes the skin is the first place a whole-body condition shows up:

• Dark, velvety skin in skin folds (acanthosis nigricans): insulin resistance or type 2 diabetes.
• Yellow skin and eyes: liver disease, gallstones blocking the bile duct, or breakdown of red blood cells.
• A butterfly rash across the cheeks: lupus.
• Yellowish plaques on the eyelids: high cholesterol.
• Easy bruising or tiny bleeding spots: low platelets, blood disorders or blood-thinning medicines.
• Itching without a rash: kidney or liver disease, thyroid disease, iron deficiency, or rarely lymphoma.
• Thickened, tight skin on the fingers and face: scleroderma.

When to worry: the ABCDE check for moles

For moles and dark spots, dermatologists use the ABCDE rule:

• Asymmetry: the two halves do not match
• Border: ragged, blurred or notched edges
• Color: several shades of brown, black, red, white or blue
• Diameter: larger than 6 mm (about a pencil eraser), though melanomas can be smaller
• Evolving: any change in size, shape, color, height, or new bleeding or itching

Also watch for the "ugly duckling": a spot that looks different from all your others.

How doctors diagnose skin abnormalities

Your doctor will ask when the change started, whether it itches or hurts, what makes it better or worse, new products or medicines, sun exposure, and other symptoms such as fever or joint pain. They will look at the whole skin, including nails, scalp and mouth. Tests may include:

• Dermoscopy: a handheld magnifier with light to examine moles and growths
• Skin scraping: examined under a microscope for fungus or scabies
• Swab: for bacteria or viruses
• Patch testing: to identify contact allergies
• Skin biopsy: a small sample removed under local anesthetic for laboratory diagnosis
• Blood tests: when an internal cause is suspected

Treatment and home care

Treatment depends on the cause. General measures that help many common skin abnormalities:

• Use a fragrance-free moisturizer at least twice a day, especially after bathing.
• Wash with lukewarm water and a gentle, soap-free cleanser.
• Stop any new product that might be causing irritation.
• Avoid scratching. Keep nails short and use cool compresses for itch.
• Protect your skin from the sun with clothing, shade and SPF 30 or higher sunscreen.
• Try over-the-counter 1% hydrocortisone cream for a few days on small itchy patches (not on the face for long, or on infected skin), following the label.

See a doctor rather than treating at home when you are unsure what a lesion is, especially a growth, sore or changing mole.

Frequently asked questions

What does skin abnormalities mean?

It means any part of the skin that looks different from normal: a change in color, texture or thickness, or a rash, bump, blister, scale or sore. It is a description rather than a diagnosis. The cause can be anything from dry skin or eczema to infection, a benign growth or, less often, skin cancer.

When should I see a doctor about a skin change?

See a doctor for a mole or spot that is new or changing, a sore that has not healed within 4 weeks, a rash lasting more than 2 weeks, or skin that is red, hot and spreading. Get urgent help for a rash with fever, swelling of the face or breathing trouble, or widespread blistering.

Can stress cause skin abnormalities?

Stress does not usually cause new skin disease, but it commonly triggers flares of eczema, psoriasis, acne, rosacea and hives, and it can make itching worse. Managing stress, sleep and skincare often reduces flares.

Are skin changes a sign of cancer?

Most are not. But a new or changing mole, a pearly or shiny bump that bleeds, a scaly patch that does not heal, or a growing lump can be skin cancer. Early skin cancers are very treatable, so get any suspicious spot checked promptly.