Psoriasis

Question 1

What is psoriasis?

Answer 1

Chronic, genetically, immune-mediated inflammatory skin condition

Question 2

What kind of lesions is psoriasis usually characterised by?

Answer 2

Usually characterised by typically well-defined, scaly plaques

Question 3

What is the prevalence of psoriasis?

Answer 3

3% of UK population

Question 4

How does the prevalence of psoriasis compare between males and females?

Answer 4

M:F is equal

Question 5

In what age group is the peak incidence of psoriasis?

Answer 5

20s and 50s

Question 6

Is there any genetic factor to psoriasis?

Answer 6

>1/3 have family history

Question 7

As well as the physical implications of psoriasis, what else must be considered?

Answer 7

Psychological implications

Question 8

What other diseases is psoriasis linked to?

Answer 8

Is a systemic disease, linked to metabolic syndrome and cardiovascular disease

Question 9

Describe the appearance of psorasis lesions?

Answer 9

Red scaly plaques, often symmetrical distribution

Question 10

What causes psoriasis?

Answer 10

Overactivity of the immune system, excessive production of TH1 cytokines including TNF-alpha:

• Vascular proliferation (erythema), increased cell turnover (plaques and scaling)

Question 11

Excessive production of what causes psoriasis?

Answer 11

TH1 cytokines including TNF-alpha

Question 12

What is the aetiology of psoriasis?

Answer 12

• Genetics
• Environment
• Infection
  
  • Strep, candida
• Drugs
  
  • Lithium, beta blockers, NSAIDs, steroid withdrawal
• Trauma
• Sunlight

Question 13

What infections can cause psoriasis?

Answer 13

Strep

Candida

Question 14

What drugs can cause psoriasis?

Answer 14

Lithium

Beta blockers

NSAIDs

Steroid withdrawal

Question 15

Explain the pathogenesis of psoriasis?

Answer 15

Epidermal infiltration by activated T cells:

• Increased epidermal cell proliferation and turnover
• Cell cycle reduced from 28 days to 3-5 days
• Capillary angiogenesis
• Excessive production of TH1 cytokines, especially TNF-alpha, which is linked to flares

Often family history, so genetic link

Question 16

What are some precipitants to psoriasis?

Answer 16

• Trauma
• Infection
• Drugs
• Sunlight
• Stress
• Smoking
• Alcohol
• HIV

Question 17

Explain the histology of psoriasis?

Answer 17

• Hyperkeratosis (thickening of stratum corneum) with parakeratosis (keratinocytes with nuclei in statum corneum)
• Neutrophils in stratum corneum (munro’s microabscesses)
• Hypogranulosis, no granular layer (needed for barrier function)
• Psoriasiform hyperplasia: acanthosis (thickening of squamous cell layer) with elongated rete ridges
• Dilated dermal capillaries
• Perivascular lymphohistiocystic infiltrate, T cell infiltration

Question 18

What is hyperkeratosis?

Answer 18

Thickening of stratum corneum

Question 19

What is parakeratosis?

Answer 19

Keratinocytes with nuclei in stratum corneum

Question 20

What is Munro’s microabscesses?

Answer 20

Neutrophils in stratum corneum

Question 21

What layer of the skin is needed for barrier function?

Answer 21

Granular layer

Question 22

What is acanthosis?

Answer 22

Thickening of squamous cell layer

Question 23

What are some different subtypes of psoriasis?

Answer 23

• Chronic plaque psoriasis
  
  • Accounts for 90% of psoriasis cases
  • Commonly managed with topical treatments in primary care
• Guttate psoriasis
  
  • Commonly post-viral
  • Usually self-limiting
  • Responds well to phototherapy
• Palm-plantar psoriasis
  
  • Have greatest impact on quality of life
• Scalp psoriasis
  
  • Differential diagnosis of seborhoeic dermatitis
• Nail psoriasis
  
  • Pathognomonic features include pitting and onycholysis
• Flexural/inverse psoriasis
  
  • Lack of scale
• Pustular psoriasis
• Erythrodermic psoriasis
  
  • “Red man” syndrome
  • >90% of body surface involved
  • Needs in-patient treatment

Question 24

What is the most common subtype of psoriasis?

Answer 24

Chronic plaque psoriasis (accounts for 90% of cases_

Question 25

How is chronic plaque psoriasis commonly managed?

Answer 25

With topical steroids in primary care

Question 26

When does guttate psoriasis commonly occur?

Answer 26

Post-viral

Question 27

What treatment does guttate psorasis respond well to?

Answer 27

Phototherapy

Question 28

What kind of psoriasis has the greatest impact on quality of life?

Answer 28

Palm-plantar psoriasis

Question 29

What is a differential diagnosis for scalp psoriasis?

Answer 29

Seborrhoeic dermatitis

Question 30

What is erythrodermic psorasis also known as?

Answer 30

"Red man" syndrome

Question 31

How much of the body is involved in erythrodermic psorasis?

Answer 31

\>90% of body surface

Question 32

How is psorasis diagnosed?

Answer 32

Can be clinical based on typical presentation or skin biopsy if atypical

Question 33

What are some differential diagnosis for psoriasis?

Answer 33

* Seborrhoeic dermatitis * Especially scalp, face * Lichen planus * Check forearm, oral mucosa * Mycosis fungoides * Older patient, sudden onset of plaques or treatment resistant plaques

Question 34

What is the initial treatment for psoriasis?

Answer 34

Emollients: * Creams vs ointments Vitamin D3 analogues with or without topical steroids Tar creams Topical steroids: * Fleuxural/genital area Salicyclic acid (keratolytic) Dithranol Anthralin

Question 35

What are emollients?

Answer 35

Cosmetic preparations used for protecting, moisturizing, and lubricating the skin

Question 36

What is the treatment for psoriasis if initial treatment fails?

Answer 36

* UVB phototherapy * Acitretin * Teratogenic, impairment of LFTs/lipids * Methotrexate * Cyclosporin * Risk of renal impairment/cancer * Inpatinet tar * Biologics * Qualifying criteria, costly * Anti-TNF (etanercept, infliximab, adalimbumab) * IL-12, 23 inhibitor (ustekinumab) * IL 17 inhibitor (ixekizumab, secukinumab)

Question 37

What are some biologics for the treatment of psoriasis if initial treatment fails?

Answer 37

* Anti-TNF (etanercept, infliximab, adalimbumab) * IL-12, 23 inhibitor (ustekinumab) * IL 17 inhibitor (ixekizumab, secukinumab)

Question 38

What is a possible future medicine for psoriasis?

Answer 38

Future medicine is kinase inhibitors: * Ethical/cost dilemmas * Examples are adalimumab and methotrexate

Question 39

What is the treatment of erythrodermic psoriasis?

Answer 39

* Admit * Fluid balance * Bloods/IV access * Thick greasy ointment emollients

Question 40

How is psoriasis monitred?

Answer 40

* Psoriasis Area Severity Index (PASI) * Body area, redness, thickness, scaliness) * Dermatology Life Quality Index (DLQI) * Bloods etc if on systemic treatment

Question 41

What does PASI stand for?

Answer 41

Psoriasis area severity index

Question 42

What does PASI consider?

Answer 42

Body area, redness, thickness, scaliness

Question 43

What does DLQI stand for?

Answer 43

Dermatology life quality index

Question 44

What is the prognosis of psoriasis?

Answer 44

Exacerbations and remissions occur, can be difficult to treat May progress to arthritis in 5-10% Die earlier than controls on average Associated with other co-morbidities: * Cardiovascular disease, smoking, alcohol, metabolic syndrome, lymphoma, depression, suicide

Question 45

What other co-morbidities is psoriasis associated with?

Answer 45

* Cardiovascular disease, smoking, alcohol, metabolic syndrome, lymphoma, depression, suicide

Question 46

How is psorasis usually managed?

Answer 46

Usually managed in primary care with topical treatment and addressing risk factors: * Smoking, alcohol, stress, drugs

Question 47

What are some systemic treatments for psoriasis?

Answer 47

* Phototherapy, oral (retinoids, immunosuppresants), biologics