Pitryriasis Rosea

What is pityriasis rosacea?

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Pityriasis rosacea is a skin condition that appears as red, raised scaly patches. Also known as Christmas Tree Rash, pityriasis rosacea can appear on different parts of the body. This is a relatively common condition, but it most often occurs in people between ages 10 and 35. While pityriasis rosacea is not often painful, it can cause itching, which may be severe. This, along with other potential symptoms, can cause significant discomfort.

In many cases, pityriasis rosacea clears on its own. Still, receiving and confirming a diagnosis can help rule out other, more dangerous conditions. Additionally, if your case of pityriasis rosacea lasts for longer than three months, or if symptoms don’t resolve after two months, you will want to schedule another appointment. Connecting with a dermatologist can provide proactive treatment for pityriasis rosacea and other skin conditions.

What causes pityriasis rosacea?

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The exact cause of pityriasis rosacea remains unknown. Many doctors believe the skin condition is a post-viral rash. Specifically, researchers think pityriasis rosacea is a result of a herpes virus variant. The rash is often seen as the immune system’s response to the viral infection. Unlike dermatitis, external stimuli are not connected to the appearance of pityriasis rosacea. In other words, Christmas Tree Rash is not caused by allergy, fungus, or bacteria, and it does not appear to be contagious.

While there are no known pityriasis rosacea causes, there are certain risk factors to keep in mind. While any person can develop this rash, it is most common in people with female bodies. The rash is also most common in childhood and early adulthood – specifically between ages 10 and 35. It is most likely to appear in the spring and autumn months. Some researchers have posited that autoimmune factors may play a role in pityriasis rosacea’s cause and development.

What are symptoms of pityriasis rosacea?

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Pityriasis rosacea symptoms are easy to identify. The rash appears as a scattering of raised, red, scaly patches. Unlike other types of rashes, pityriasis rosacea moves in stages. Documenting how a Christmas Tree Rash progresses can help steer a dermatologist to a more accurate diagnosis.

In many cases, pityriasis rosacea patients begin with a “mother,” or primary patch. This patch of red, scaly skin is typically the first to appear. It can measure up to 4 centimeters in diameter. The mother patch is most likely to occur on the abdomen, chest, or back.

Over time – typically a few days or weeks – smaller scaly patches begin to form around the mother patch. These smaller spots often spread, beginning to form the pattern of a pine tree – hence the “Christmas Tree Rash” nickname. Patches can develop anywhere on the body, but they don’t often occur on the face, scalp, feet, or palms.

Auxiliary symptoms often accompany this rash. These include:

  • Itching, especially on scaly patches. This can be mild, moderate, or severe.
  • Fatigue
  • Headache
  • Low-grade fever
  • Sore throat

In many cases, patients have general feelings of being unwell before the rash appears. It is unclear whether these feelings are associated with the instigating virus or with the rash itself. In around 80 percent of cases, pityriasis rosacea lasts for between one and three months. It is not known to leave permanent marks or scars.

Is pityriasis rosacea linked to other conditions?

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In some cases, pityriasis rosacea can resemble other conditions. In most cases, these other conditions are more severe than Christmas Tree Rash. If you begin to see spreading, scaly patches, it is important to see a dermatologist as soon as possible. A diagnosis can rule out other, more dangerous conditions and lead to proactive treatment. Pityriasis rosacea is often mistaken for the following conditions:

  • Syphilis: This chronic and infectious disease is transmitted via direct contact with a lesion. When left untreated, syphilis can result in severe disability and eventually death. Syphilis lesions can sometimes resemble those associated with pityriasis rosacea.
  • Psoriasis: Psoriasis is a chronic autoimmune disorder that manifests as inflamed skin. The skin often appears as dry, scaly, red, and thickened patches. In some cases, these patches may have gray scales.
  • Pityriasis Versicolor: These skin conditions have very similar symptoms. However, pityriasis versicolor is caused by a yeast infection. You will need to treat this rash with antifungal medications.
  • Cancer: Certain types of skin cancers and lymphoma may resemble the mother patch in a pityriasis rosacea patient.
  • Tinea: This fungal skin infection, also known as ringworm, may resemble pityriasis rosacea patches.
  • Drug Side Effects: Certain drugs cause side effects that resemble pityriasis rosacea rashes. These drugs include bismuth, clonidine, barbiturates, interferon, imatinib mesylate, and certain arsenic compounds.

Pityriasis rosacea is thought to be an immune response. As a result, doctors have linked this specific rash with other conditions. For example, SARS-CoV-2 infection, as well as certain COVID-19 vaccines, has been associated with pityriasis rosacea. Skin rashes, like Christmas Tree Rash, occur in around one-third of long-COVID-19 patients.

How is pityriasis rosacea diagnosed?

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Pityriasis rosacea is diagnosed with a dermatology appointment. During the appointment, the doctor will observe the rash. They may use certain tests, like blood work or collecting a sample, to rule out similar-appearing conditions, like psoriasis, ringworm, and eczema. The doctor will also ask about whether the rash has changed in recent days or weeks. If you have photos of the rash from days or weeks before the appointment, show them to the doctor.

In advance of your appointment, compile a list of medications, vitamins, and supplements you have taken in the last several months. Additionally, take stock of all symptoms you are experiencing – even if they don’t appear to be related to your rash. The more information he doctor has, the more accurate the diagnosis will be.

Are there treatments for pityriasis rosacea?

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Yes, there are treatment options available for pityriasis rosacea. However, they are not always necessary. In most cases, this rash will heal on its own, often within two months. However, many doctors recommend over-the-counter treatments and at-home remedies to help patients deal with itchy skin. This usually includes oatmeal baths, hydrocortisone (anti-itch) cream, and antihistamines, like Benadryl and Zyrtec. If you have pityriasis rosacea, be sure to moisturize the affected area often, either with lotion or bath oil. Look for products free of synthetic fragrance and alcohol. Additionally, avoid using drying soaps on affected body parts, and avoid hot showers, as these can cause pain and further itching.

For those with severe cases of Christmas Tree Rash, a doctor might recommend therapies to complement symptomatic treatment. Tor example, certain antiviral and antibiotic drugs may support faster healing. Some doctors prescribe phototherapy with UVB ultraviolet light. However, sunburn may worsen the appearance of pityriasis rosacea patches.

There are few complications associate with pityriasis rosacea development and treatment. However, people with melanated skin may develop dark spots once the rash disappears. In most cases, these spots fade within several weeks. Additionally, Christmas Tree Rash in pregnant people has been linked to a great chance for premature delivery and miscarriage. If you are pregnant and have a rash that resembles pityriasis rosacea, see your doctor as soon as possible.

What is the outlook for people with pityriasis rosacea?

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Pityriasis rosacea is not a dangerous condition. Most rashes disappear within several weeks or months. Christmas Tree Rash does not often cause lasting problems. However, you should make an appointment with your primary care provider or dermatologist to rule out other, more harmful conditions. In some cases, people with darker skin may experience post-rash discoloration. This typically fades within several weeks.

Those with long-term rashes (3+ months) should schedule a follow-up appointment with a medical provider. This might be an indication that the initial diagnosis was incorrect. Additionally, pregnant people who develop Christmas Tree Rash, or similar conditions, should visit a doctor right away. A primary care provider or dermatologist can diagnose what type of rash you have. Then, you can discuss next steps.