Psoriasis

Question 1

What is psoriasis

Answer 1

Hyperproliferation of keratinocytes
A chronic immune mediated disease
causes red flaky crusty patches of skin covered in silvery scales

Question 2

Where is psoriasis usually found

Answer 2

On the extensors (blows, knees, arms, legs)

Question 3

Causes of psoriasis

Answer 3

35-90% have a family history

Other: infection, drugs, trauma, sunlight, OBESITY

Question 4

Cell cycle time

Answer 4

Usually 28 days, in psoriasis it renews every 3-5 days

Question 5

What causes the red skin appearance

Answer 5

VEGF is secreted - causing new blood vessel formation to the skin

Question 6

Skin presentation

Answer 6

Sharply demarcated plaques
Light skin - pink or purple
dark skin - dark brown or hyper pigmented
Comes with sterile pustules

Question 7

What is koebner phenomenon

Answer 7

Psoriasis forming at the site of a scratch/injury (in a place that it wouldn’t usually form)

Question 8

Types of psoriasis

Answer 8

Chronic plaque (symmetric and on extensor surfaces)
Guttate psoriasis - all over body in little plaques (often due to bacterial infections)
Palmo-plantar psoriasis - Small areas of pustules (very painful involving hands and feet)
Scalp psoriasis
Nail psoriasis - most difficult to treat
Flexural/inverse psoriasis - scales and plaques are rubbed off so just look bright red
Pustular psoriasis - often caused by pustular drug eruption
erythrodermic psoriasis - skin failure >80% of body surface

Question 9

What is the management of Psoriasis

Answer 9

thick skin moisturisers 
vitamin D3 - slow keratinocyte proliferation 
topical steroids 
coal tar cream 
salicylic acid (to remove scale)

Question 10

Care of psoriasis in secondary care

Answer 10

Oral retinoids - these are teratogenic

crude coal tar