Pityriasis Alba

What is pityriasis alba?

Pityriasis alba is a common childhood skin condition that causes raised, round or oval patches of lighter skin. These patches can be up to an inch in size.

The patches are cosmetic and only affect your child’s appearance. So, they don’t always need treatment. But treatment is available. The patches may come and go during childhood. This condition usually goes away completely before adulthood.

Pityriasis alba is harmless and it isn’t a sign of anything serious. But it’s still important to take your child to see their provider if you notice any changes to their skin.

What are the symptoms of pityriasis alba?

Symptoms of pityriasis alba include a patch of skin that’s:

• Lighter in color (less pigmented than the skin around it)
• Round, oval or irregularly shaped
• Flat or slightly elevated (higher than the skin around it)
• Itchy (occasionally)
• Dry
• Lightly scaled texture

The patches start as discolored (slightly lighter than your natural skin tone or red or pink) spots. They then become even lighter (almost white). Pityriasis alba patches are more noticeable if you have a darker skin tone.

Where will I have symptoms of pityriasis alba?

Your child may experience pityriasis alba patches on their:

• Arms
• Back
• Chest
• Face
• Neck

What causes pityriasis alba?

The exact cause of pityriasis alba is unknown. Severe forms may be the result of a decreased amount of melanin. Melanin is a substance in your skin that gives your skin color. Research is ongoing to learn more about it. 

The condition also seems to be related to:

• Atopic dermatitis
• Eczema

Pityriasis alba isn’t contagious and it doesn’t spread from person to person.

Is pityriasis alba a vitamin deficiency?

There isn’t enough evidence to suggest that a vitamin deficiency causes pityriasis alba.

What triggers pityriasis alba?

Sun exposure may make pityriasis alba skin patches more visible. This is because your surrounding skin may darken with continued sun exposure while these patches stay a lighter color. The patches are also more at risk of sunburn than the skin surrounding them. 

What are the risk factors for pityriasis alba?

If your child has a biological family history of certain conditions, they may be more likely to develop pityriasis alba. These conditions include:

• Asthma
• Atopic dermatitis
• Eczema
• Hay fever (allergic rhinitis)

At what age does pityriasis alba occur?

Children usually get pityriasis alba. This condition is most common between ages 3 to 16. It usually goes away by the time kids reach adulthood. While rare, adults may develop it.

What are the complications of pityriasis alba?

Your child may occasionally experience itchy skin with pityriasis alba. If they scratch, they risk breaking open their skin. It might bleed and lead to scarring or an infection.

If your child experiences itchy skin on pityriasis alba patches, contact a healthcare provider for recommendations on how to relieve this symptom.

How is pityriasis alba diagnosed?

A healthcare provider will diagnose pityriasis alba during a physical examination. During the exam, they’ll ask about your child’s symptoms and health history. Then, they’ll look at your child’s skin. The lighter patches of skin usually lead to an accurate diagnosis.

What tests diagnose pityriasis alba?

Tests aren’t common but may help rule out conditions with similar symptoms. Your child’s provider may offer the following:

• KOH prep test. A provider gently scrapes your child’s skin with a scalpel to get a skin sample. They’ll add potassium hydroxide (KOH) to a slide to examine the sample under a microscope. This helps make sure it’s not a fungal infection.
• Skin biopsy. This is done if the diagnosis isn’t clear by observation, and your provider is worried it may be serious. During a skin biopsy, a provider removes a small sample of your child’s skin to examine it under a microscope.
• Wood’s lamp exam. This test uses ultraviolet light to examine skin color differences. Pityriasis alba patches show blurrier borders and don’t glow under the light.

How do you treat pityriasis alba?

Treatment isn’t necessary for pityriasis alba, since it usually goes away on its own. But treatment options are available.

Your provider may recommend using topical corticosteroids. A common corticosteroid is mild hydrocortisone cream. If you use corticosteroids on your child’s face, make sure to avoid their eyes.

For rare but widespread cases, your child’s provider may consider:

• Topical calcineurin inhibitors (TCIs). These are creams that suppress your child’s immune system (like tacrolimus ointment and pimecrolimus cream).
• Topical vitamin D. A common vitamin D ointment is calcitriol.
• PUVA therapy (photochemotherapy). Your child’s provider puts medicine made from plants (psoralen gel or lotion) on pityriasis patches. Then, they expose their skin to long-wave ultraviolet radiation (UVA).
• Targeted phototherapy. Your child’s provider uses focused ultraviolet light on areas of their affected skin.

At-home pityriasis alba treatments

The following may help your child manage pityriasis alba symptoms at home:

• Using moisturizing creams or lotions daily
• Applying petroleum jelly to the affected skin

In addition, you can protect your child’s skin from sun exposure, which can make their symptoms more noticeable, by:

• Using broadband sunscreen with at least 30 SPF to prevent tanning and sunburn
• Wearing long-sleeved shirts, long pants and a wide-brimmed hat when outside

What can I expect if my child has pityriasis alba?

Pityriasis alba is a harmless skin condition. It will go away on its own. Sometimes, symptoms like itchy skin are bothersome. Or this condition may affect your child’s mental health if they feel like they look different from their peers.

A healthcare provider can offer treatment options that may clear these patches sooner, including creams or lotions that you can apply to your child’s skin at home. Make sure you follow the directions for use.

This condition doesn’t leave any lasting effects on your child’s skin. The color of their skin will return once the patches clear up.

How long does pityriasis alba last?

There isn’t a cure for pityriasis alba. Most cases go away on their own within a year. It can take several months to years for the patches on your child’s skin to go away completely. Skin patches may come and go but they often completely disappear before adulthood.

When should my child visit a healthcare provider?

Visit your child’s healthcare provider if you notice changes to their skin. Let their provider know if they’re scratching at their skin or you notice these patches make them feel self-conscious. Treatment options are available.

What questions should I ask my child’s healthcare provider?

If your child receives a pityriasis alba diagnosis, you may want to ask their provider:

• Does my child need treatment? If so, what do you recommend?
• Are there side effects of the treatment?
• How often do I use a moisturizer on my child’s skin?
• How do I prevent my child from scratching their skin?