Lichen planus and pityriasis

Question 1

Lichen Planus (LP)

Answer 1

A skin disorder of unknown aetiology. Most likely immune mediated. mostly middle aged adults with a slight female predominance

Question 2

Classic features of LP

Answer 2

Itchy, papular rash on the palms/soles, flexor surfaces of the arms and genitals. polygonal rash with Wickham’s striae.

Question 3

Six ‘P’s

Answer 3

Purple
Polygonal
Papules
Plaques
Pruritic
Planar

Question 4

Wickham’s striae

Answer 4

White lace pattern of the surface of the lesions

Question 5

Nail changes in LP

Answer 5

nail bed thinning and longitudinal ridging

Question 6

Oral Involvement in LP

Answer 6

Oral involvement in 50% of patients.

Question 7

Does LP koebnerise?

Answer 7

Yes

Question 8

Lichen sclerosus

Answer 8

A chronic inflammatory condition effecting the anogenital region of women and glans/foreskin of men,

Question 9

Causes of lichen sclerosus (LS)

Answer 9

Some evidence of autoimmune mechanism with associations with other autoimmune conditions.

Question 10

Incidence of LS

Answer 10

More in women, most in pre-pubertal or post-menopausal women

Question 11

Presentations of LS

Answer 11

Porcelain-white papules or plaques which may progress to crinkled patches. Active lesions may have areas of ecchymosis, hyperkeratosis or bullae.

Question 12

Symptoms of LS

Answer 12

Itching, soreness, blisters.
Dyspareunia/painful erections due to phimosis.
If there is meatal scarring, poor urinary stream or dysuria.

Question 13

Pityriasis (or tinea) versicolor (PV)

Answer 13

a superfical cutaneous fungal infection caused by pityrosporum ovale/malassezia furfur with fir tree distribution

Question 14

Features of PV

Answer 14

Mainly effects the trunk causing mildly itchy patches which are either hypopigmented, pink or brown. Scale is common

Question 15

Risk factors for PV

Answer 15

Can occur in healthy people but more likely in immunosuppression, malnutrition or cushings

Question 16

Management of PV

Answer 16

Topical antifungals (terinafine or selenium sulphide) or can use oral itraconazole

Question 17

Management of LP

Answer 17

Topical steroids are the first line and if extensive then oral steroids or immunosuppression may be required.

Question 18

Typical presentation of Pityriasis rosea (PR)

Answer 18

Young adults with an abdominal herald patch followed by erythematous, oval, scaly patches

Question 19

Cause of PR

Answer 19

Unknown, may be linked to HHV-7. tends to effect young adults.

Question 20

Features of PR

Answer 20

Trunk herald patch followed by erythematous, oval, scaly patches following the langers lines.

Question 21

Progression of PR

Answer 21

Self limiting and resolves after 4-6 wks.

Question 22

Causes of drug related LP

Answer 22

Gold, quinine or thiazides

Question 23

Pitted Keratolysis

Answer 23

Occurs in people who sweat alot, damp or smelly feet which are white with clusters of punched-out pits. caused by Corynebacterium

Question 24

Palmoplantar pustulosis

Answer 24

Crops of sterile pustules on the palms and soles. Red thickened skin which is scaly and may crack. More common in smokers.

Question 25

Management of LS

Answer 25

Biopsy may be needed to exclude other causes.
Topical steroids and emollients are major treatment
Increased risk of Vulval Cancer.