Lichen planus and pityriasis Flashcards
Lichen Planus (LP)
A skin disorder of unknown aetiology. Most likely immune mediated. mostly middle aged adults with a slight female predominance
Classic features of LP
Itchy, papular rash on the palms/soles, flexor surfaces of the arms and genitals. polygonal rash with Wickham’s striae.
Six ‘P’s
Purple Polygonal Papules Plaques Pruritic Planar
Wickham’s striae
White lace pattern of the surface of the lesions
Nail changes in LP
nail bed thinning and longitudinal ridging
Oral Involvement in LP
Oral involvement in 50% of patients.
Does LP koebnerise?
Yes
Lichen sclerosus
A chronic inflammatory condition effecting the anogenital region of women and glans/foreskin of men,
Causes of lichen sclerosus (LS)
Some evidence of autoimmune mechanism with associations with other autoimmune conditions.
Incidence of LS
More in women, most in pre-pubertal or post-menopausal women
Presentations of LS
Porcelain-white papules or plaques which may progress to crinkled patches. Active lesions may have areas of ecchymosis, hyperkeratosis or bullae.
Symptoms of LS
Itching, soreness, blisters.
Dyspareunia/painful erections due to phimosis.
If there is meatal scarring, poor urinary stream or dysuria.
Pityriasis (or tinea) versicolor (PV)
a superfical cutaneous fungal infection caused by pityrosporum ovale/malassezia furfur with fir tree distribution
Features of PV
Mainly effects the trunk causing mildly itchy patches which are either hypopigmented, pink or brown. Scale is common
Risk factors for PV
Can occur in healthy people but more likely in immunosuppression, malnutrition or cushings
Management of PV
Topical antifungals (terinafine or selenium sulphide) or can use oral itraconazole
Management of LP
Topical steroids are the first line and if extensive then oral steroids or immunosuppression may be required.
Typical presentation of Pityriasis rosea (PR)
Young adults with an abdominal herald patch followed by erythematous, oval, scaly patches
Cause of PR
Unknown, may be linked to HHV-7. tends to effect young adults.
Features of PR
Trunk herald patch followed by erythematous, oval, scaly patches following the langers lines.
Progression of PR
Self limiting and resolves after 4-6 wks.
Causes of drug related LP
Gold, quinine or thiazides
Pitted Keratolysis
Occurs in people who sweat alot, damp or smelly feet which are white with clusters of punched-out pits. caused by Corynebacterium
Palmoplantar pustulosis
Crops of sterile pustules on the palms and soles. Red thickened skin which is scaly and may crack. More common in smokers.
Management of LS
Biopsy may be needed to exclude other causes.
Topical steroids and emollients are major treatment
Increased risk of Vulval Cancer.
