Psoriasis

Question 1

What is psoriasis?

Answer 1

• autoimmune disease
• inflammatory skin condition
• chronic
• causes hyperproliferation of keratinocytes

Question 2

Types of psoriasis

Answer 2

• chronic plaque psoriasis
• guttate
• seborrhoeic
• flexural (inverse)
• pustular
• palmoplantar pustulosis
• erythrodermic

Question 3

What is auspitz sign?

Answer 3

scratch and gentle removal of psoriatic scales causes capillary bleeding

Question 4

How does plaque psoriasis present?

Answer 4

• well-demarcated, red, raised plaques
• covered by flakey silvery-white scales
• itchy
• typically on extensor surfaces, may be on scalp
• nail changes in 50%
• psoriatic arthritis in some

Question 5

What are raindrop lesions characteristic of?

Answer 5

guttate psoriasis

Question 6

How does guttate psoriasis present?

Answer 6

• raindrop lesions (small, red, individual papules) on trunk, limbs, sometimes scalp (not palms or soles)
• often preceding infection e.g. strep throat
• often presents in childhood

Question 7

How does flexural/inverse psoriasis present?

Answer 7

• in flexures (skin folds)
• smooth, shiny red lesions
• more common in overweight people

Question 8

How does pustular psoriasis (von Zumbusch psoriasis) present?

Answer 8

• erythema, initially on flexor surfaces before spreading to other body surfaces
• tender skin
• small, sterile pustules
• pustules dry and peel within 2 days leaving skin glazed and smooth
• may have systemic Sx: fever, chills, severe itching, tachycardia, exhaustion
• may be induced by suddenly stopping steroids
• can be life-threatening

Question 9

How does palmoplantar pustolosis present?

Answer 9

• a form of pustular psoriasis
• sterile pustules and yellow-brown macules on palms and soles (that then peel off)
• can progress to deep fissures
• can be life-threatening

Question 10

How does erythrodermic psoriasis present?

Answer 10

• generalised erythema affecting >90% of the body
• facial sparing
• nail changes
• itching and pain
• scales fall off in sheets
• severe, unstable, highly labile disease
• affects ability to control temperature
• may need admission
• dermatological emergency, can be life-threatening

Question 11

How does photosensitive psoriasis present?

Answer 11

• in association with sunburn

- guttate lesions or painful diffuse inflamed plaques in areas of sunburn

Question 12

How does HIV-induced psoriasis present?

Answer 12

• may be atypical, unusually severe

- may have sudden onset of Sx including pustular or erythroderma

Question 13

What nail changes may be seen in psoriasis

Answer 13

• pitting
• onycholysis (separation from nail bed)
• subungal hyperkeratosis (keratin build-up in space created by onycholysis)
• salmon patches/oil-spots (reddish discolouration)

Question 14

Presentations of psoriatic arthritis

Answer 14

DR SAM
DIP joint involvement
Rheumatoid-like
Spondyloarthritis
Asymmetrical oligoarthritis
Mutilans arthritis

Question 15

Pharmacologiacal Mx of psoriasis

Answer 15

• emollients
• vitamin D analogue (calciprotriol) + potent topical corticosteroid (e.g. betamethasone valerate 0.025%) applied once a day but at different time to eachother
• if scales are problematic: topical salicyclic acid 2-3x/week

Also:

• topical retinoids
• scalp preparations
• dithranol (athralin)
• coal tar preparations
• topical calcineurin inhibitors

Question 16

When prescribing topical steroids, remember… (3)

Answer 16

• do not use potent steroids on one area for >8 weeks
• very potent only in secondary care
• topical steroids are only suitable for LOCALISED psoriasis - avoid use on widespread psoriasis where there is a risk of unstable disease

Question 17

Lifestyle Mx of psoriasis

Answer 17

• smoking cessation
• alcohol within recommended limits
• weight loss if overweight

Question 18

Mx of extensive psoriasis

Answer 18

phototherapy

• UVB
• PUVA (psoralen PO + UVA)

UVB best for most types
PUVA best for palpoplantar

Question 19

CIs to phototherapy

Answer 19

• pustular/erythrodermic psoriasis
• photosensitive psoriasis
• immunosuppressant treatment
• skin cancer
• for PUVA: pregnancy, breastfeeding, liver/renal failure, cataracts

Question 20

Pharmacological Mx of extensive/severe psoriasis

Answer 20

Oral therapies

• methotrexate
• retinoids
• ciclosporin
• mycophenolate mofetil
• fumaric acid esters
• biologics

Question 21

Mx of psoriasis on face

Answer 21

• mild-moderately potent topical steroids

- topical tacrolimus ointment

Question 22

Mx of scalp psoriasis

Answer 22

• Tar-based shampoo e.g. T-gel, capasal
• antifungal shampoo
• coconut oil
• potent topical steroid

Question 23

Indications for referral for psoriasis

Answer 23

• diagnostic uncertainty
• patient request for further counselling/education
• failure to respond/adverse reaction to topical Mx after 3 months
• need for systemic/photo/inpatient therapy or very potent topical steroids
• disability preventing work
• acute unstable psoriasis
• erythroderma or generalised pustular psoriasis

Question 24

Which forms of psoriasis should be treated as a medical emergency?

Answer 24

• generalised pustular psoriasis

- erythrodermic psoriasis

Question 25

Which medications precipitate psoriasis?

Answer 25

• beta blockers
• chloroquine
• lithium