Psoriasis

Question 1

Definition

Answer 1

Relapsing remitting chronic, systemic, inflammatory skin disease with a multifactorial aetiology

Question 2

Epidemiology and risk factors

Answer 2

FHx
Obesity
Smoking and alcohol consumption
Medications:
- ACE inhibitors
- Beta-blockers
- NSAIDs
- Lithium
- Hydroxychloroquine
- Antibiotics: tetracycline, penicillin
- Steroid withdrawal

Question 3

Associations

Answer 3

• Psoriatic arthritis
• Inflammatory bowel disease
• Mood disturbances
• Increased risk of CVD

Question 4

Pathophysiology

Answer 4

Immune-mediated condition with abnormal T cell activity that stimulates the proliferation of keratinocytes = formation of scale-like plaques on the skin.
Pro-inflammatory cytokines, such as IL-17, are thought to mediate the T cell activity

Question 5

Genetic associations

Answer 5

HLA-B13
HLA-B17
Identical twins

Question 6

Exacerbating factors

Answer 6

• Skin trauma (Koebner’s Phenomenon)
• Stress
• Infection
• Certain medications

Question 7

Improving factors

Answer 7

Sunlight

Question 8

Signs

Answer 8

• Well-demarcated erythematous plaques + scaly appearance = esp on extensor surfaces of body
• Plaques itchy and excoriation marks may be visible. Removal of scales on plaques lead to capillary bleeding (Auspitz signs )
• 50% Px = nail changes:
  = pitting
  = onycholysis
  = subungual hyperkeratosis
  = nail loss

Question 9

Symptoms

Answer 9

• Skin plaques
• Pruritus
• Nail changes

Question 10

Types of psoriasis

Answer 10

• Chronic plaque psoriasis (MC)
• Scalp psoriasis = CPP in the scalp area
• Facial psoriasis = well demarcated plaques on face + maybe hairless
• Flexural psoriasis = affects groin, genital area, axillae, inframammary folds, abdominal folds, sacral and gluteal cleft
• Localised pustualar psoriasis: plaques + pustules on palms and soles
• Gluttate psoriasis: widespread teardrop lesions triggered by strep infection
• Erythrodermic psoriasis

Question 11

Diagnosis

Answer 11

Clinical diagnosis

Question 12

Treatment

Answer 12

FIRST LINE =
- Px education: stop smoking, wt loss
- Regular emollients: reduces scale and relieve pruritus
- Topical corticosteroid AND topical Vit D prep: once daily for 4 weeks = then assess. Good response then continue Tx until skin clear. If there is a poor response Tx different

Question 13

Tx if bad response to first line

Answer 13

> 4 weeks: Continue Tx +4 weeks
+ 4 weeks:
- continue for another 4 weeks, if still poor response = stop t.steroids, and continue t.Vit D twice daily for up to 12 weeks
- stop t.steroids and continue with t.Vit D
- coal tar preperation once or twice daily
+12 weeks:
- Potent

Question 14

Other treatments

Answer 14

Scalp psoriasis:
- topical corticosteroids +/or coal tar shampoo
- topical vit D
face and flexur al psoriasis:
- topical corticosteroids: once or twice daily for up to 2 weeks + emolliant
Gluttate psoriasis:
- treated similar to CPP

Question 15

Complications

Answer 15

Psoriatic arthropathy
Mood disturbances
CVD
DVT