White Pityriasis: What It Is and How Other Types of Pityriasis Differ

You don't notice a light spot on the skin right away: at first it just seems like a lighter area of skin. Then you look more closely at the edge, at the scaling, at whether the size is changing. In everyday language, the word "pityriasis" (lichen) brings together various skin diseases.

What pityriasis is

"Pityriasis" is a general term for skin diseases of different origins in which the main element of the rash is small itchy nodules or inflammatory spots. This includes eczema, shingles, tinea versicolor, pityriasis rosea, ringworm, scaly lichen (psoriasis), and lichen planus — each has its own cause.

Light and dark spots in atopic eczema: what they look like and where they appear

In atopic eczema, the skin can be dry, cracked, and flaky, and its color can be white, red, purple, or gray, lighter or darker than the surrounding skin depending on skin tone. In children under two years of age, the rash is more often on the face, scalp, hands, and feet; in older children and adults — on the inner side of the knees and elbows, on the neck, hands, and feet. In adults, changes may be limited to the hands, eyelids, or genital area. Itching can be severe and sometimes begins before the rash itself.

Atopic eczema is not contagious; you cannot "catch" it from another person.

Causes and what worsens atopic eczema symptoms

The cause of atopic eczema is not always known, but the risk is higher if one or both parents have atopic eczema, and also if the person or their close relatives have asthma or hay fever. The disease itself is not caused by allergy, but flare-ups can be triggered by contact with allergens and irritants (soap, detergents, pets, certain fabrics, pollen, dust mites, certain foods), heat or temperature changes, skin infections, stress, and hormonal changes, for example during pregnancy.

What types of pityriasis exist

The list of types of pityriasis includes diseases of different origins: fungal (tinea versicolor, ringworm), viral (shingles, pityriasis rosea), non-infectious (eczema, psoriasis, lichen planus). Separate names such as white, asbestos-like, linear, annular, and round pityriasis are not distinguished in this list, so the name alone cannot tell you the cause — a doctor determines this during examination.

How pityriasis is diagnosed and when to see a dermatologist

The doctor examines the skin, clarifies personal and family history, and if necessary orders a skin biopsy to confirm the diagnosis or rule out other causes of dryness and itching. Cultures for infection and allergy tests are possible — they are useful for forms that are difficult to treat and for rashes that occur only in certain areas after contact with a substance.

• the spots are growing
• blisters, crusts, oozing, or pustules have appeared
• the skin is painful, swollen, or hot
• the rash is accompanied by fever and general malaise
• the rash suddenly worsened or spread

Such changes may indicate a secondary infection, and then a doctor's examination is needed.

A light spot by itself is not a reason to call an ambulance; 103/112 — for a life-threatening condition, for example signs of stroke or heart attack, or serious injury.

This material is for reference and does not replace a dermatologist's consultation.

This content is for reference and does not replace a doctor's consultation. Medical disclaimer