Related Subjects:
|Nikolsky's sign
|Koebner phenomenon
|Erythema Multiforme
|Pyoderma gangrenosum
|Erythema Nodosum
|Dermatitis Herpetiformis
|Lichen Planus
|Acanthosis Nigricans
|Acne Rosacea
|Acne Vulgaris
|Alopecia
|Vitiligo
|Urticaria
|Basal Cell Carcinoma
|Malignant Melanoma
|Squamous Cell Carcinoma
|Mycosis Fungoides (Sezary Syndrome)
|Xeroderma pigmentosum
|Bullous Pemphigoid
|Pemphigus Vulgaris
|Seborrheic Dermatitis
|Pityriasis/Tinea versicolor infections
|Pityriasis rosea
|Scabies
|Dermatomyositis
|Toxic Epidermal Necrolysis
|Stevens-Johnson Syndrome
|Atopic Eczema/Atopic Dermatitis
|Psoriasis
It often begins as a large single pink patch on the chest or back. This patch may be scaly and is called a "herald" or "mother" patch.
About
- Scaly (pityriasis) and pink (rosea).
Aetiology
- Possibly a post-viral response.
- Occurs in clusters (schools, army barracks, families, etc)
- More frequent in the winter.
- Risk of Transmission seems low
- Most common between the ages of 10 and 35 years.
Clinical
- Common acute, self-limiting skin condition usually mild and lasts about 6 to 8 weeks.
- May complain of a mild headache and feel systemically unwell then they get a herald patch
- A single patch, herald patch comes up a few days, or even a couple of weeks, before the rest of the rash. It is usually single. Usually on the main part of the body (trunk). Larger (2-5 cm diameter). Round or oval and, at first, bright red, and scaly. Later it becomes paler with a ring of scaling (known as a collarette) just inside its edge.
- After a few days a second rash comes up made up of many small oval patches (1-2 cm across) which is pink and, like the herald patch, they may also have a ring of scaling just inside their edge. Most are on the trunk or limbs and neck too. Can form a Christmas tree pattern
- Comes up in crops, at intervals of a few days, for a week or two and then fade slowly over the next 6 to 8 weeks, usually leaving no trace. They may leave light or dark patches in people with dark skin, but these marks do eventually fade. Second attacks are rare.
Differentials
Investigations
- Blood: normal and not usually indicated
- Rarely a skin biopsy
Management
- Pityriasis rosea goes away by itself and treatment does little to speed this up.
- Antihistamines or a mild corticosteroid such as Hydrocortisone cream or emollients may help if the rash is itchy and extensive
- If the itch is still severe despite these treatments, your doctor may suggest a stronger steroid cream or treatment with ultraviolet light.
- There is no reason to keep children with pityriasis rosea away from school
- There is no need to treat the rash if it is not causing any symptoms.
- If the rash does not clear up after 3 months, consult GP again.