Psoriasis

Answer 1

• a chronic inflammatory skin
  disorder
• occurs due to T-cell mediated
  autoimmunity stimulating keratinocyte
  hyperproliferation and cytokine production

Question 2

contributors to psoriasis

Answer 2

• strong genetic association
• environmental factors - lack of
  sunlight, infection (strep, HIV), stress, skin trauma (Koebner’s), medications

Question 3

chronic plaque psoriasis

Answer 3

• the commonest form
• symmetrical distribution of itchy, well-demarcated, erythematous plaques with overlying white/silvery scale
• fissuring within plaques is common and plaques will show the Auspitz sign
• symmetrically distributed over extensor body surfaces (elbows, knees) and scalp

Question 4

psoriatic nail disease

Answer 4

pitting, oil-drop discolouration, subungual hyperkeratosis, crumbling of the nail plate, and onycholysis
treated with topical corticosteroids and vitamin D3 analogues

Question 5

psoriatic flare ups

Answer 5

• can be triggered by topping oral steroids or very potent topical steroids
• can be triggered by streptococcal throat infections (can lead to erythroderma)
• severity is classified with the psoriasis area and severity index tool (PASI)

Question 6

psoriasis links

Answer 6

• CVD (risk of MI, metabolic syndrome)
• inflammatory bowel disease
• coeliac disease
• psoriatic arthritis

Question 7

conservative management of psoriasis

Answer 7

• ↓ stress ↓ alcohol ↓ smoking
• ↑ sun exposure

Question 8

first line treatment for psoriasis

Answer 8

• topical therapies - emollient + potent corticosteroid (beclometasone) + vit. D OD (Dovobet, Dovonex) for 4 weeks
• facial psoriasis = moderate potency preparations

Question 9

second line treatment for psoriasis

Answer 9

• coal tar
• calcineurin inhibitors = Pimecrolimus
• Tazarotene gel (retinoid)
• short contact Dithranol (often causes irritation and staining)

Question 10

third line treatment for psoriasis

Answer 10

• slow keratinocyte proliferation but often have severe S/E and require frequent monitoring:
• non-biological agents:
• methotrexate = in chronic psoriasis
• cyclosporine or prednisolone = in inducing remission in flare
• other agents - Acitretin (retinoid), Fumaric Acid Esters, Hydroxycarbamide, Sulfasalazine
• biological therapies:
• anti-TNF, reserved for severe treatment-resistant psoriasis

Question 11

psoriasis referral

Answer 11

• psoriasis is severe or extensive, affecting >10% of body surface area
• cannot be controlled with topical therapy and has frequent flares
• the disease is having a large impact on the person’s wellbeing

Question 12

phototherapy for psoriasis

Answer 12

• narrow-band UV-B therapy is given 2 – 3 times per week
• photochemotherapy can be used in patients with more extensive or resistant disease - uses a photosensitising drug like PUVA + UVB
• complication - ↑ risk of skin cancer

Question 13

guttate psoriasis

Answer 13

• active skin eruption, appearing as multiple small pink papules with a fine scale (raindrop lesions) on the trunk, upper arms, and thighs
• often presents ~2 weeks following streptococcal URTI and is common in children
• usually resolves without treatment when the underlying infection is treated
• emollients and abx may therefore be sufficient
• acceleration of rash clearance with UVB phototherapy
• topical therapies (coal tar, steroid creams) are difficult due to wide distribution of the rash

Question 14

palmoplantar pustular psoriasis

Answer 14

• yellow sterile pustules
• red, dry and thickened palms and soles, often with fissuring
• most likely to lead to psoriatic arthritis

Question 15

flexural psoriasis

Answer 15

• treated as for chronic plaque psoriasis
• phototherapy is relatively ineffective as the folds are hidden from light exposure

Question 16

scalp psoriasis

Answer 16

• can lead to alopecia, which is rarely scarring
• management with coal tar or Ketoconazole shampoo