Psoriasis

Question 1

What is the epidemiology of psoriasis?

Answer 1

2-4% of people

Any age - peaking onset at 15-25 then 50-60

Tends to
persist for life, with fluctuations in extent and severity

Strong family history

Question 2

What is the aetiology and pathology of psoriasis?

Answer 2

Immune mediated inflammatory disease

- Complex genetic associations + environmental triggers, as per usual…

Question 3

What are the different presentations of psoriasis?

Answer 3

Age of onset:

• early = <35yrs (75%)
• Late = >50yrs

Acute e.g. guttate, Vs. chronic e.g. plaque

Localised e.g. scalp, palmoplantar, Vs. generalised

Small (<3cm) vs large (<3cm) plaques

Nail signs present or absent

Chronic plaque psoriasis:

• Well demarcated, erythematous plaques with silvery scales
• Mostly affects extensors (elbows, knees), trunk, scalp (or anywhere else)
• Often do not change with treatment

Acute guttate:
- Post strep infection, widespread small plaques, often resolves after several months

Question 4

What nail signs might be present in psoriasis?

Answer 4

Pitting, ridging, yellowing

Onycholysis

Subungal hyperkeratosis (scaling under the nail from excessive proliferation of keratinocytes)

Question 5

What non-cutaneous features are important to look for in psoriasis?

Answer 5

Skin lesions often come first

Joint disease:

• Psoriatic arthritis
• Spondyloarthropathy

Cardiovascular:

• Metabolic syndrome
• T2DM

GI:

• IBD (also uveitis)
• Coeliac

Psychological:
- Can cause severe distress for people

Question 6

What is an objective way of measuring psoriasis severity?

Answer 6

PASI - Psoriasis Area and Severity Index

• Redness
• Thickness
• Scaling

All measured from absent (0) - mild - moderate - severe - very severe (4)

Question 7

What is a way of measuring a patient’s life with psoriasis? Incl. psychological and social factors

Answer 7

Dermatology Life Quality Index (DLQI)

Covers q’s on:

• itchiness, pain
• embarrassment
• impact on ADLs and clothes choice
• impact on social and leisure time , sport, work and study, sex etc

Question 8

What is the stepwise approach to managing psoriasis?

Answer 8

General measures + emollients

• Regular emollients
• Don’t use soaps
• Stop smoking
• Lose weight
• Manage stress
• Careful sun exposure

Topical treatment:

• Topical steroids
• Vitamin D-like compounds +/- steroid e.g. calcipotriol (can irritate skin)
• Coal tar
• Dithranol

Phototherapy:

• UVB
• Can lead to skin aging and predispose to skin Ca

Systemic therapy:

• Methotrexate (OW + folic acid), tiredness, mouth ulcers, lung/liver fibrosis, teratogen
• Acitretin - dry skin, hair thinning, tiredness, deranged LFTs + lipids
• Ciclosporin - HTN, renal functioning impaired
• ALL NEED MONITORING

Biologics:

• Etanercept, infliximab, abdalinumab (Anti TNF)
• Screen for TB, HIV, Hep B+C - as can active these infections
• Increased risk of cancer
• Expensive and not possible for everyone