Psoriasis

Question 1

What is it

Answer 1

Chronic hyper proliferative disorder with well-demarcated red scaly plaques

Question 2

Types

Answer 2

Chronic plaque psoriasis
Flexural psoriasis
Guttate
Erythrodermic and pustular

Question 3

Pathophysiology of all types

Answer 3

Abnormally excessive and rapid growth of epidermal layer, as a result of an inflammatory cascade causing premature maturation of keratinocytes.
These keratinocytes then secrete IL-1, IL-6 and TNF-a which signal further inflammation.

Question 4

Aetiology of Chronic Plaque Psoriasis

Answer 4

Polygenic, but dependent on specific triggers (infection, drugs such as lithium, high alcohol use, stress).
Potentially T lymphocyte driven.

Question 5

Clinical presentation of Chronic Plaque Psoriasis

Answer 5

Well demarcated, salmon-pink silvery scaling occur on the extensor surfaces of the limbs (elbow, knee).
Scalp involvement is common and most often seen at the hair margin.
Changes fingernail appearance; pitting, whitening, onycolysis and slight bleeding.

Question 6

Aetiology of Flexural psoriasis

Answer 6

Heat
Trauma
Infection

Question 7

Clinical presentation of Flexural psoriasis

Answer 7

Red glazed non-scaly plaques, in flexures (groin, natal cleft, sub-mammary).
No satellite lesions.

Question 8

Aetiology of guttate psoriasis

Answer 8

Genetic predisposition; associated with specific HLA alleles.
Triggered by streptococcal infection

Question 9

Clinical presentation of guttate psoriasis

Answer 9

Most common in children and young adults.

Explosive eruption of very small teardrop shaped plaques over the trunk 2 weeks after a streptococcal sore throat.

Question 10

Aetiology of erythrodemic and pustular

Answer 10

Usually occurs secondary to progressively worsening plaque psoriasis OR precipitated by infection, tar, drugs or the withdrawal of corticosteroids

Question 11

Clinical presentation of erythrodemic and pustular

Answer 11

Most severe.
Potentially life threatening.
Widespread intense inflammation of the skin.
Malaise, pyrexia, circulatory disturbances.

Question 12

What is most common psoriasis

Answer 12

Chronic plaque psoriasis

Question 13

Chronic plaque psoriasis epidemiology: Has a double peak of onset - what are these peaks?

Answer 13

16-22

55-60

Question 14

Guttate psoriasis epidemiology

Answer 14

Usually affects under 30s

Question 15

Diagnosis

Answer 15

Clinical

Question 16

Treatment of psoriasis (Chronic plaque, Flexural, Guttate)

Answer 16

Control, not cure.
Topical: reasurrance and emollient.
Possibly corticosteroids.
Vitamin D analogues: Calcipotriol
Phototherapy: Ultraviolet A radiation with photosensitising agent, oral or topical psoralen
Systemic therapy: oral retinoic acid derivatives (acitretin)
Calcineurin inhibitors: tacrolimus (immunosuppressive)

Question 17

Treatment of Erythrodemic and pustular psoriasis

Answer 17

Bed rest
Emollients
Cool wet dressings
Nutritional support
Avoid topical tar and phototherapy in the earlier phases

Question 18

Complications of Erythrodemic and pustular psoriasis

Answer 18

Dehydration
Cardiac failure,
Overwhelming infection
Death

Question 19

Generally explain what psoriasis is

Answer 19

Increased production of skin cells
Chronic
Skin cells are normally made and replaced every 3 to 4 weeks, but in psoriasis, the process only takes about 3 to 7 days.
Thought to be a problem with immune system, where it attacks healthy skin cells

Question 20

Epidemiology of psoriasis

Answer 20

Affects around 2% of people in UK
Most often develops <35 year olds
Men and women equally affected

Question 21

General appearance of skin in someone with psoriasis

Answer 21

Red, flaky, crusty patches of skin covered with silvery scales