Pityriasis – Types: Rosea, Alba or Simple, Rubra Pilaris and Versicolor – Explained in Detail

Important aspects

It is one of the skin diseases that have common injuries that resemble dandruff, such as scales without apparent signs of inflammation.

Pityriasis types include:

  • Pityriasis rosea.
  • Pityriasis alba (also called pityriasis streptomyces, simple, erythema streptomyces).
  • Pityriasis Rubra pilaris.
  • Pityriasis versicolor (tinea versicolor).

What is pityriasis rosea?

Pityriasis rosea begins as a giant pink spot found on the body’s trunk. The patch appears one to two weeks later, with the more minor pink marks in a “Christmas tree” shape.

Pityriasis rosea gives a mild itching in 50% of cases and disappears spontaneously in an average of six to eight weeks.

Pityriasis rosea is sometimes accompanied by mild symptoms similar to the flu and can mimic fungal infections and other conditions.

Pityriasis rosea does not have prolonged effects on health and is not directly contagious. Lifetime immunity often occurs after an episode.


Pityriasis rosea is a common rash usually seen in individuals between 10-35 years of age.

The rash lasts six to eight weeks and rarely extends 12 weeks or more. Once a person has pityriasis rosea, it usually does not recur again in his life.

Pityriasis rosea is characterized as an asymptomatic pink, scaly plaque called “herald patch” or mother patch, which measures between 2 and 10 centimeters.

It is a pink to the red-dry plate that appears on the back, chest, or neck and has a well-defined, scaly edge.

One or two weeks after the initial appearance of the herald patch, a person will then develop many small pink spots through their trunk, arms, and legs.

Pityriasis alba

This is characterized by hypopigmented patches, round to oval, on the face, arms, neck, or shoulders. The patches vary in size, generally being a few centimeters in diameter.

The color is white or light pink. The scales are thin and adhesive.

The patches are generally clearly delimited; The edges may be erythematous and slightly raised. As a general rule, Pityriasis is asymptomatic. However, there may be mild itching. The disease occurs mainly in children and adolescents.

The cause is unknown. Dehydrated skin after exposure to strong sunlight seems to be contributory. Efforts to find an infectious agent – bacterial, viral or fungal – have been unsuccessful.

Pitiriasis rubra pilaris

It is a chronic skin disease characterized by small follicular papules, disseminated yellowish-pink patches, and, often, solid confluent palmoplantar hyperkeratosis.

The bumps are the most important diagnostic feature, being more or less acuminate, reddish-brown color, about the size of the head of the pinhead, and crowned by a central horn plug. In the center of the horn, a hair, or part of one, is usually fitted. The disease usually manifests first by scaling and erythema of the scalp.

The eruption is limited initially, having a preference for the sides of the neck and trunk and the extensor surfaces of the extremities.

Then, as new lesions occur, the extensive areas become patches of various sizes, which seem exaggerated and feel like a nutmeg grater.

Participation is generally symmetrical and diffuse, with small islands characteristic of normal skin within the affected areas.

Pitiriasis Versicolor (tinea versicolor)

Fine scales, status, or nummular patches appear in the upper trunk and extend towards the upper part of the arms, especially in young adults who transpire freely.

The individual patches are yellowish or brownish macules in pale skin, or hypopigmented macules in dark skin, with delicate scales. There may be slight itching and swelling of the patches.

This common fungal disease is more prevalent in the tropics, where high humidity and high temperatures, and frequent exposure to sunlight.

Is there any effective treatment?

There are several alternatives for the few patients whose itching is severe enough to require treatment.

Slightly to moderately potent topical steroids and oral antihistamines (many available without a prescription) will suffice.

Sometimes ultraviolet light administered in a doctor’s office or sunbathing carefully can decrease the itching enough to be tolerable.

The second stage of Pityriasis erupts with many oval points, ranging in diameter from 0.5 centimeters (the size of a pencil eraser) to 1.5 centimeters (the size of a peanut).

This rash is usually confined to the trunk, arms, and legs, rarely occurring on the face and neck. Pityriasis is generally generated on the front, hands, and feet.

Who is more prone?

For the most part, Pityriasis is equally common in men and women. It usually occurs in children and young adults between 10-35 years of age. It does not have a racial predominance. Most people only develop Pityriasis once in their life.


The exact cause of Pityriasis remains unknown. Recently, Pityriasis has been associated more strongly with a human herpes family virus called human herpesvirus type 6 or 7.

Pityriasis is not caused by any herpes, but it is known to be associated with common types of genital herpes, oral herpes, or chickenpox.

While the mode of transmission (how it is passed between people) is also unknown, respiratory contact has been postulated.

Pityriasis does not appear to be directly or immediately contagious to close contacts or health providers exposed to the rash. Most people with known exposure to Pityriasis do not seem to get the rash.

How is it diagnosed?

Pityriasis is usually diagnosed only based on its appearance, particularly the beginning of the distinctive patch of the large herald and the symmetrical presentation of the Christmas tree.

In addition, the herald’s patch tends to have a fine scale with a defined edge, the so-called “collarette.”


A doctor can scratch the skin and examine the scales under a microscope to rule out other skin disorders to detect a fungal infection that could mimic Pityriasis.

In addition, blood tests, including rapid plasma reagent (RPR), can be done to detect secondary syphilis, which can also mimic Pityriasis. A skin biopsy may be necessary to rule out skin conditions in some cases.

In rare cases, the rash may take other forms. Rounded protrusions (papular rash) can be seen in young children, pregnant women, and people with dark skin.

Blisters (vesicular erythema) can be seen in infants and young children. The herald patch may not appear in some people, or two heraldic patches may occur together.

Before the herald patch appears, you may feel tired and like you have a cold. You may have a headache, nausea, sore throat, and loss of appetite.

Pityriasis is similar to the rash seen in other skin conditions, including ringworm of the skin, tinea versicolor, eczema, and psoriasis.

A rash similar to Pityriasis can also be caused by syphilis and certain medications such as antibiotics.

If you have a rash on the palms of your hands or the soles of your feet, consult your doctor. This may be a sign of something more severe than Pityriasis.

Pityriasis disappears without treatment. It usually lasts around 6 to 8 weeks. If you have itching in the rash, you may want to use skin lotions and lubricants to soothe the itching.

If the symptoms are severe, your doctor may prescribe anti-inflammatory medications such as Corticosteroids to relieve itching and reduce the rash.

Although treatment is not necessary, antiviral medicines like Aciclovir can shorten the rash’s time, especially if you take them when the rash first starts.

Exposing the rash to sunlight can make it disappear more quickly. But exposing your skin to the sun for too long can cause sunburn and increase your risk of skin cancer.

If the rash lasts more than three months, contact your doctor.

To relieve itching at home:

Try to stay calm. Getting too hot and sweating can make the rash and itching worse.

Avoid taking showers or hot baths. Keep the water as cool as you can tolerate.

Add a handful of oats (ground to a powder) to your bath. Or you can try an oatmeal bath product, like Avenue.

Try a hydrocortisone cream without a 1% prescription for small itchy areas. Use the cream sparingly on the face or genitals. Note: Do not use the cream in children under two years old unless your doctor tells you to.

Do not use in the rectal or vaginal area in children under 12 unless your doctor tells you to.