Psoriasis

Question 1

what is psorasis?

Answer 1

chronic autoimmune disease characterised by well-dermarcated, erythematous, scaly plaques

Question 2

what are the 5 types of psoriasis?

Answer 2

• chronic plaque
• flexural (inverse)
• guttate
• pustular
• generalised/erythodermic

Question 3

what is chronic plaque psoriasis?

Answer 3

• commonest type
• symmetrical plaques on the extensor surfaces, scalp and lower back

Question 4

what is flexural (inverse) psoriasis?

Answer 4

• smooth, erythematous plaques without scale
• in flexures and skin folds

Question 5

what is guttate psoriasis?

Answer 5

• multiple small, tear-drop shaped erythematous plaques
• occur on the trunk
• after a streptococcal infection in young adults

Question 6

what is pustular psoriasis?

Answer 6

• multiple petechiae and pustules
• on palms and soles

Question 7

what is generalised/erythrodermic psoriasis?

Answer 7

• rare but serious
• erythroderma and systemic illness

Question 8

describe the typical cutaneous manifestation of psoriasis

Answer 8

itchy, well-dermarcated circular-to-oval bright red/pink elevated lesions (plaques) with overlying white or silvery scale, distributed symmetrically over extensor body surfaces and scalp

Question 9

what nail changes are seen in psoriasis?

Answer 9

• nailbed pitting
• onycholysis (separation of nail plate from nailbed)
• subungual hyperkeratosis (thickening of the nailbed)

Question 10

what are the risk factors for triggering psoriasis?

Answer 10

• skin trauma (koebner phenomenon)
• infection - strep, HIV
• drugs
• withdrawal of steroids
• stress
• alcohol + smoking
• cold/dry weather

Question 11

what drugs can trigger psoriasis?

Answer 11

• lithium
• beta-blockers
• NSAIDs
• ACEi
• TNF-alpha inhibitors
• anti-malarials (e.g. chloroquine and hydroxychloroquine)

Question 12

what are the risk factors for developing psoriasis?

Answer 12

• family history
• HIV infection
• obesity
• smoking

Question 13

what is koebner phenomenon?

Answer 13

skin lesions occur at sites of skin injury in otherwise healthy skin

Question 14

what is the differential diagnosis for koebner phenomenon?

Answer 14

• psoriasis
• lichen planus
• vitiligo

Question 15

how does vitamin D help psoriasis?

Answer 15

reduces keratinocyte proliferation

Question 16

what is the topical treatment of psoriasis?

Answer 16

1. potent topical corticosteroid OD (e.g. betnovate) + topical vitamin D OD (e.g. dovonex)
2. stop corticosteriod + topical vitamin D BD
3. stop vitamin D + potent corticosteroid BD

dithranol + tar = alternatives

Question 17

what is the phototherapy management of psoriasis?

Answer 17

1. narrowband UVB phototherapy
2. psoralen + UVA (PUVA)

Question 18

what is the systemic treatment of psoriasis?

Answer 18

1. methotrexate
2. ciclosporin (1st line if rapid disease control needed/palmoplantar pustulosis/contraception)
3. acitretin

Question 19

what biological treatment can be used in psoriasis?

Answer 19

• infliximab
• etanercept
• adalimumab

Question 20

what is the strength of different topical steroids?

Answer 20

“Help Every Budding Dermatologist”
mild = Hydrocortisone 0.5%
moderate = Eumovate
potent = Betnovate
very potent = Dermovate

potent/very potent NOT for face or genitals
very potent only to be prescribed by dermatologists

Question 21

what are the side-effects of acitretin?

Answer 21

• teratogenic
• hepatotoxicity
• elevated lipids

Question 22

what are the side-effects of ciclosporin?

Answer 22

5 H’s:
Hypertrophy of the gums
Hypertrichosis
Hypertension
Hyperkalaemia
Hyperglycaemia