Psoriasis

Question 1

Name six types of psoriasis

Answer 1

Chronic plaque
Guttate
Palmo-plantar
Pustular
Inverse
Erythrodermic

Question 2

Describe the appearance and distribution of chronic plaque psoriasis

Answer 2

Itchy, well-demarcated circular/oval red-pink plaques
Overlying white scale
Present on extensor surfaces; scalp, knees, elbows, lower back
Symmetrical distribution

Question 3

What is Kobner’s phenomenon?

Answer 3

Appearance of new skin lesions on areas of cutaneous injury (e.g. a scratch) in otherwise healthy skin. It is also known as the isomorphic response.
The new lesions have the same clinical and histological features as lesions of the patient’s original skin disease

Question 4

Describe the appearance and distribution of guttate psoriasis

Answer 4

Small, drop-like pink papules with a fine scale
Generalised but worse on trunk and extremities
Causes mild itching

Question 5

Describe the appearance and distribution of palmo-plantar psoriasis

Answer 5

Red, scaly, well-demarcated plaques. Hyperkeratotic areas. Painful cracking/fissuring of the skin. Appears mostly on the palms and soles.

Question 6

Describe the appearance and distribution of pustular psoriasis.

Answer 6

White pustules (blisters of non-infectious pus) appear anywhere on the body, although may be particularly common on the palms and soles. 
May also have associated systemic symptoms.

Question 7

Describe the appearance and distribution of inverse psoriasis.

Answer 7

No scale (gets rubbed off); lesions appear as shiny pink/red demarcated plaques. Occur mostly in the flexures, particularly the armpits.

Question 8

Describe the appearance and distribution of erythrodermic psoriasis

Answer 8

Generalised redness, with finer/flakier scale than is seen in other types of psoriasis. Covers >80% of the body.

Question 9

What risks/complications are associated with erythrodermic psoriasis?

Answer 9

Infection
Dehydration
Fever, hypotension and other signs of systemic illness

Question 10

Which type of psoriasis is often associated with infection? Describe the clinical presentation.

Answer 10

Guttate psoriasis:
Usually occurs secondary to a streptococcal URTI (although it can be unrelated)
Lesions generally appear 2-3 weeks after the infection

Question 11

Describe the three lines of treatment for chronic plaque psoriasis

Answer 11

1. topical treatments e.g. steroids, vitamin D, dithranol, tar
2. phototherapy, UVB, pUVA, systemic treatments
3. systemic biologics

Question 12

What systemic treatments may be used in the second line treatment of psoriasis?

Answer 12

Retinoids e.g. acitretin

Immunosuppressants e.g. methotrexate, cyclosporin

Question 13

What can trigger pustular psoriasis?

Answer 13

Systemic steroid withdrawal
Pregnancy
Hypocalcaemia
Infection

Question 14

What can trigger inverse psoriasis?

Answer 14

Localised infection

• dermatophyte
• candidal
• bacterial

Question 15

What can trigger erythrodermic psoriasis?

Answer 15

S - Steroid withdrawal
H - Hypocalcaemia
I - Infection
T - Tar, Toxins (e.g. drugs)

Question 16

Describe the management of erythrodermic psoriasis

Answer 16

Patient needs to be admitted to hospital
Emmolients - ointment should be used (thick+greasy)
Cool, wet dressings
Fluid management; risk of dehydration
Nutritional support
Bloods
IV access (this becomes difficult when patient becomes dehydrated/hypotensive)
Systemic/biologic treatment

Question 17

What are the main biologic therapies that can be used in the management of psoriasis?

Answer 17

Anti-TNF

• Adalimumab
• Etanercept
• Infliximab

IL-12,23
- Ustekinumab

Question 18

Which two indexes are used to assess progress of psoriasis management?

Answer 18

Psoriasis Area Sensitivity Index

• physician-led
• assesses surface area, colour, thickness and scale

Dermatology Quality of Life Index
- patient-led