Psoriasis

Question 1

What is the pathophysiological mechanism of psoriasis?

Answer 1

T cell mediated autoimmune disease, abnormal infiltration of T cells causing release of cytokines (interleukins, TNF) and inducing increased keratinocyte proliferation

Question 2

A patient has rash on extensor surfaces. What might be the cause?

Answer 2

psoriasis

Question 3

Name two histological features of psoriasis

Answer 3

acanthosis (epidermal thickening) and parakeratosis (nuceli in stratum corneum)

1. Hyperproliferation of keratinocytes, resulting in irregular thickening of epidermis= acanthosis 2. Loss of granular layer 3. Nuclei are retained in stratum corneum=parakeratosis 4. Inflammatory cell infiltration in dermis and epidermis

Question 4

What are differences between psoriasis and atopic eczema?

Answer 4

less itchiness in psoriasis, can present at any age whereas atopic ezcema presents in childhood. Demarcation

Question 5

Which diseases are linked to psoriasis?

Answer 5

metabolic syndrome, liver disease, alcohol misuse, depression, psoriatic arthritis

Question 6

List three types of psoriasis?

Answer 6

plaque, guttate, pustular, erythrodermic, flexural

Question 7

Patient with psoriasis has appendix removed. They develop psoriatic plaque around the scar. What is this known as?

Answer 7

Koebner phenomenon

Question 8

What are classical clinical features of psoriasis?

Answer 8

salmon pink, demarcated, silvery scale, distribution is symmetrical, extensor surface pattern, thickened patch

Question 9

If psoriasis hasn’t responded to topical treatment and UV therapy, what could you try next?

Answer 9

systemic therapy- immunosuppressants, oral retinoid, biologics

Question 10

Which vitamin analogue can be used topically as first line treatment in psoriasis?

Answer 10

vitamin D= first line, vit A retinoid=not first line

Question 11

In psoriasis, pin-point bleeding can occur if a scale is scraped off= Auspitz sign. Why does this occur?

Answer 11

capillaries in the dermis are close to the surface in psoriasis, tortuous, and numerous, thus is scale is scraped off then bleeding will occur as the most superficial capillaries are torn

Question 12

Name four features of psoriatic nail involvement

Answer 12

pitting, onycholysis, subungal hyperkeratosis, roughened and discoloured nail surface

Question 13

Name an example of a vit D analogue

Answer 13

calcitriol

Question 14

What are advantages and disadvantages of vit D analogues?

Answer 14

Advantages- effective, clean, convenient. Disadvantages- greasy, skin irritation, need constant treatment

Question 15

List three triggers for psoriasis?

Answer 15

stress, infections, skin trauma (kobner phenomenon), drugs, smoking

Question 16

List three general signs of psoriasis

Answer 16

1. Plaques
2. Nail changes
3. Seronegative arthritis

Question 17

Describe the plaques that develop in psoriasis

Answer 17

symmetrical, demarcated, silvery scale, red plaque

Question 18

Which parts of the body does psoriasis affect?

Answer 18

flexures, axillae, groin, scalp, behind ears, sacrum, navel

Question 19

Name two features of psoriatic arthritis

Answer 19

Mono/oligo arthritis
Assymetrical polyarhtritis
Psoriatic spondylitis

Question 20

Which infection is associated with guttate psoriasis?

Answer 20

strep

Question 21

Which type of psoriasis may be localised to the palms and soles?

Answer 21

pustular

Question 22

Which manifestation of psorasis is there severe systemic upset?

Answer 22

erythroderma and generalised pustular

Question 23

List three differentials for psoriatic like lesions

Answer 23

eczema, tinea= ringworm, seborrhoeic dermatitis

Question 24

List four aspects of psoriasis management

Answer 24

1. Education- avoidance of triggers
2. Emollients
3. Topical therapy
4. UV phototherapy
5. Immunosuppressants
6. Biologics

Question 25

List two topical treatments for psoriasis

Answer 25

Vit D3 analogue- calcipotriol
steroids
retinoids

Question 26

List three non-biologicals/immunosuppressants for psoriasis

Answer 26

methotrexate
ciclosporin
acetretin (vit A analogue)

Question 27

List three biologicals used in psoriasis treatment

Answer 27

infliximab
etanercept
adalimumab