Pityriasis Rosea Differential Diagnosis Table

Pityriasis Rosea Differential Diagnosis Table:

Pityriasis rosea is an acute and self-limited exanthematous rash, which usually resolves spontaneously in six weeks. The most frequent season is during temperate climates. The most common cause of this condition is due to herpes virus reactivation.

How to Distinguish Pityriasis Rosea from Other Conditions

Differences between Pityriasis Rosea and Viral Exanthem – Diagnosis

Viral exanthem is a rash accompanied by a viral infection. There is fever, body aches, anorexia, and discomfort.

• Pityriasis rosea’s most typical clinical presentation begins with oval salmon patches with a red collar. After 2 weeks, the rash begins, accompanied by oval pink papules distributed in a Christmas tree form, while viral exanthem lesions can have multiple variations ranging from papules to pink bumps, and they don’t follow this Christmas tree pattern.
• Pityriasis rosea is only linked to the herpes virus. Unlike viral exanthem, it can be due to different viruses such as rubella, chickenpox, etc.

Differences between Pityriasis Rosea and Drug-Induced Exanthem – Diagnosis

Exanthematic pharmacological reactions are adverse effects of hypersensitivity to a drug. The drugs linked to this type of reaction are: penicillin, sulfonamides, and to a lesser probability, benzodiazepines.

• Drug-induced exanthem is an adverse effect to a drug, while pityriasis rosea is a body response to a virus.
• Drug-induced exanthem has an absence of the herald patch among its lesions, unlike pityriasis rosea, where the main present lesion is the herald patch.

Differences between Pityriasis Rosea and Syphilis – Diagnosis

Pityriasis Rosea can be confused with syphilis, specifically secondary syphilis.

• Some symptoms of secondary syphilis include: alopecia, uveitis, deafness, and optic neuritis, while pityriasis rosea does not have present any of these symptoms.
• The route of transmission of syphilis can be through sexual contact or vertical transmission, unlike pityriasis rosea, which is not contagious.

Differences between Pityriasis Rosea and Seborrheic Dermatitis – Diagnosis

It is a chronic dermatosis characterized by erythema and scaly lesions.

• Lesions in Seborrheic dermatitis occur in places with the presence of sebaceous glands, while pityriasis rosea does not follow these characteristics.
• The elementary lesions of seborrheic dermatitis are characterized by greasy, itchy, and thick scales in regions with the presence of sebaceous glands, while the elementary lesion in pityriasis rosea is an oval pink patch known as the herald patch.
• Pityriasis rosea is usually linked to a viral infection such as the herpes virus, while seborrheic dermatitis is a fungal condition.

Differences between Pityriasis Rosea and Nummular Eczema – Diagnosis

It is an inflammatory chronic dermatitis.

• The elementary lesion of Nummular Eczema consists of well-delimited oozing-pruriginous red patches in coin form with vesicular appearance and can produce crusts and scales, while the elementary lesion in pityriasis rosea is an oval pink patch known as the herald patch.
• Nummular eczema is linked to bacterial overpopulation and in atopic patients, while pityriasis rosea is not linked to any of these factors.
• Nummular eczema affects patients over 40 years old, while pityriasis rosea usually affects young people.

Differences between Pityriasis Rosea and Guttate Psoriasis – Diagnosis

It is a rare variant of psoriasis that is usually triggered by an untreated streptococcal infection.

• Guttate psoriasis causes red spots that look like tear drops throughout the body. It can cause new lesions due to scratching, while the elementary lesion in pityriasis rosea is an oval pink patch known as the herald patch.
• Guttate psoriasis has a genetic predisposition, while pityriasis rosea has no evidence of this.

Differences between Pityriasis Rosea and Tinea Corporis – Diagnosis

It is a skin infection caused by a fungal infection.

• Tinea corporis causes pink and red-shaped plaques with vesicles with a light center and edges with scales, while the elementary lesion in pityriasis rosea is an oval pink patch known as the herald patch.
• Pityriasis rosea is usually linked to a viral infection such as the herpes virus, while tinea corporis is a fungal condition.

Differences between Pityriasis Rosea and Lichen Planus – Diagnosis

Lichen planus is a polymorphic inflammatory disease.

• Lichen planus is not pruritic; it presents pain when lesions are touched, while pityriasis rosea does not present pain when being touched.
• Lichen planus lesions are flat violet papules at the top, well delimited and have confluence. On the surface of the papules, you can find white stretch marks, known as Wickham stretch marks, while the elementary lesion in pityriasis rosea is an oval pink patch known as the herald patch.
• It occurs more frequently in genital areas symmetrically, and it affects oral mucosa, unlike pityriasis rosea that respects these areas.

Differences between Pityriasis Rosea and Pityriasis Lichenoides – Diagnosis

Lichenoid pityriasis is an eruption of an unknown cause. It is more frequent in men and is classified as acute and chronic.

• Lichenoid pityriasis lesions are bright red edematous papules that have their interior necrosed with hemorrhagic scabs. They are red-colored desquamative papules with a crawl in the center, while the elementary lesion in pityriasis rosea is an oval pink patch known as the herald patch.
• Lichenoid pityriasis is more frequent in men, while pityriasis usually affects young people.
• Lichenoid pityriasis is an immunological acquired dermatosis characterized by a T-lymphocyte disorder, while pityriasis rosea is a condition linked to the herpes virus.

Common Red Flags with Pityriasis Rosea

Pityriasis rosea does not need treatment since it is an asymptomatic and self-limited disease. In very few cases, this ex-forebble can be presented as a papular rash where rounded papules are seen. In infants, it can happen that ampoules come out, known as vesicular rash.
This disease is common in temperate climates, so the presence of an outbreak during spring and autumn may suggest an infectious origin. This condition is of good prognosis since it has a self-resolution from 6 to 8 weeks.