Symptoms and localization
Pityriasis rosea usually occurs on the chest, back and arms. However, it may spread to other parts of the body.
The rash typically begins with a large, oval or round spot called a “herald patch” that usually appears on the trunk. Within a few days to weeks, smaller patches spread and may form a “Christmas tree” pattern on the back. The patches are usually pink or reddish and have fine scaling. Other symptoms may include itching, fatigue, fever, and headache.
Diagnosis
Diagnosis of pityriasis rosea is based on a physical examination and the typical appearance of the rash. In some cases, a skin biopsy may be performed to rule out other similar conditions.
Therapy
Treatment of pityriasis rosea is aimed at relieving symptoms such as itching and inflammation. Most cases heal on their own within weeks. In some cases, topical steroids or antihistamines may be prescribed to relieve symptoms. In severe cases, light therapy or systemic steroids may be prescribed.
Course
Pityriasis rosea usually heals on its own within weeks, with no long-term effects to worry about. However, in some cases, it may take longer for the rash to resolve.
Prognosis
The prognosis of pityriasis rosea is usually good. Most cases heal on their own within weeks, with no long-term effects to worry about.
Prevention
Because the exact cause of pityriasis rosea is unknown, there are no known ways to prevent the condition. However, it is believed to be a viral infection. Some experts believe that pityriasis rosea may be caused by human herpesvirus 7 (HHV-7) or human herpesvirus 6 (HHV-6).
Risk factors
There are no known risk factors for pityriasis rosea. However, it occurs more frequently in the spring and fall.
Staging
Pityriasis rosea is usually divided into two stages: The first stage is characterized by the herald patch, and the second stage is
characterized by the appearance of smaller, round patches with scaling that typically spread across the chest, back and arms. The patches may be arranged in a characteristic “Christmas tree” pattern.
Related conditions: There are other skin conditions that can cause similar symptoms to pityriasis rosea, including psoriasis, eczema and ringworm. It is important to have a doctor make an accurate diagnosis to ensure proper treatment.
Frequency
Pityriasis rosea is a common skin condition. It affects people of all ages and genders, but is most common in people between the ages of 10 and 35.
Pathogenesis
The exact cause of pityriasis rosea is unknown, but it is thought to be a viral infection.
Classification
Pityriasis rosea belongs to the papulosquamous skin diseases and is also classified as a benign, self-limiting skin disease.
Staging: Pityriasis rosea is usually divided into two stages. The first stage is characterized by the appearance of a larger rash (called the “herald patch”), usually on the chest. The second stage is characterized by the appearance of smaller, round patches with scaling that typically spread on the chest, back and arms.
Similar diseases
There are some skin conditions that may have similar symptoms to pityriasis rosea. These include:
Nummular dermatitis: a skin condition characterized by the appearance of round, scaly patches.
Psoriasis: A chronic skin condition characterized by the appearance of red, scaly patches.
Tinea corporis: A fungal infection of the skin characterized by the appearance of ring-shaped, itchy patches.
Literature:
There are numerous scientific studies and medical articles dealing with the cause, diagnosis and treatment of pityriasis rosea. Some of the most important sources are:Chuh A, Lee A, Molinari N. Pityriasis rosea: an update on etiopathogenesis and management of difficult aspects. Indian J Dermatol. 2016;61(4):375-384.Drago F, Broccolo F, Javor S, et al. Pityriasis rosea: An update with a critical appraisal of its possible herpesviral etiology. J Am Acad Dermatol. 2009;61(2):303-318.Drago F, Ranieri E, Malaguti F, Losi E, Rebora A. Human herpesvirus 7 in patients with pityriasis rosea. J Am Acad Dermatol. 1997;36(2 Pt 1):199-201.Laughter MR, Ellis CN, Mancini AJ. Pityriasis rosea: an update on diagnosis and management. Am J Clin Dermatol. 2014;15(2):117-125.Wendling J, Tiercy K, Ramelet AA. Pityriasis rosea: diagnosis and treatment. Am Fam Physician. 2015;92(12):1084-1091.Watanabe T, Kawamura T, Jacob SE. Pityriasis rosea: an update. Acta Derm Venereol. 2015;95(8):905-912.Weigelt N, Metze D, St%C3%A4nder S. Pityriasis rosea–a critical review. Arch Dermatol Res. 2007;299(8):325-333.Web linksGerman Dermatological Society: https://www.derma.de/krankheitsbilder/pityriasis-rosea/American Academy of Dermatology: https://www.aad.org/public/diseases/rashes/pityriasis-roseaNational Organization for Rare Disorders: https://rarediseases.org/rare-diseases/pityriasis-rosea/