Lecture 7: Psoriasis Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

Describe the appearance of Psoriasis?

A

Numerous small sharply demarcated erythematous papules/plaques with a micaeceous scale

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Describe the appearance of Psoriasis in english?

A

Raised red clean-edged lesions with a sparkly scale.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How does psoriasis affect the nails?

A

Psoriasis of the nails presents with:

  • Onycholysis
  • Pitting
  • Oil spots
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are koebner’s phenonmenon and Woronoff’s Ring?

A

Koebnor’s Phenomenon - Lesions appear directly at sites of injury on the skin

Woronoff’s Ring - A blanched halo around lesions following topical therapy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Describe how Psoriasis biopsies appear histologically?

A
  • Hyperkeratosis (Thickened stratum corneum)
  • Munro’s Microabscesses (Neutrophils in S. Corneum)
  • Psoriasiform Hyperplasia (Thick squamous cell layer, aka Acanthosis)
  • Dilated dermal capillaries
  • T cell infiltration
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Whats the DDX for Psoriasis?

A

Seborrhoeic Dermatitis
Lichen Planus
Mycosis Fungoides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Describe the aetiology of Psoriasis?

A

A mixture of genetic susceptibility and an environmental trigger

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What genes determine Psoriasis susceptibility?

A

PSORS1-9 genes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the main environmental triggers for Psoriasis?

A

Infection
Drugs
Trauma
Sunlight

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Age of onset is determined by a seperate gene?

A

HLA-Cw6

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

When do most people develop Psoriasis?

A

Peaks at 20-30 and 50-60

But 75% occur before reaching 40

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the parts of Psoriasis’ pathogenesis?

A

Stressed Keratinocytes –> Th activation

Interleukins/TNF-alpha stimulate keratinocyte proliferation

Excess VEGF –> Angiogenesis

Neutrophils gather in acute disease causing pustules

Cell cycle is reduced from 28-5 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How do stressed keratinocytes leads to Th cell activation and what is the consequence?

A

Keratinocytes activate Dermal Dendritic Cells (dDC)
dDCs trigger lymph nodes to present uncertain antigen to naive T cells
T cells differentiate to Th1, 17 & 22

Th cells cause the plaque formation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How is keratinocyte proliferation stimulated?

A

Interleukins and Anti-TNFalpha amplify the inflammatory cascade

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the risk factors for Psoriasis?

A
FH
Peak ages (20-30/50-60)
Smoking
Alcohol
CVD
Depression
Drug/Light therapies
Skin cancer
Metabolic syndrome
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the systemic signs of Psoriasis?

A

Psoriatic Arthritis
Psychosocial problems
Metabolic syndrome

17
Q

How is Psoriasis diagnosed?

A

CLinically

But if atypical take a biopsy and diagnose histologically

18
Q

How would you treat Psoriasis in the GP?

A

Soap Substitutes
Emollients
Coal Tar Creams

Vit D3 analogues
Topical Steroids (Genitals/flexures)
Salicylic acid (keratolytic)
19
Q

How do Vit D3 analogues help Psoriasis?

A

They inhibit epidermal proliferation

20
Q

How would a dermatologist treat Psoriasis?

A

Crude Coal Tar (Day or inpatient treatment)

Dithranol

UVB phototherapy (for Guttate)

21
Q

What are the systemic treatments for Psoriasis?

A

Retinoids

Immunosuppression

Biologics

22
Q

Describe retinoid use in Psoriasis?

A

E.g. Acitretin

You must monitor LFTs, lipids and educate that they’re teratogenic for up to 3 yrs post treatment

23
Q

Describe immunosuppresion use in Psoriasis?

A

Cyclosporin - Fast acting so good for initial treatment (risks renal damage)

Methotrexate - Good for Psoriatic Arthritis but risks marrow suppression and liver damage

24
Q

Describe biologic use in Psoriasis?

A

Anti-TNF e.g. Infliximab
ILK-12, 23 e.g. Ustekinumab

Patients can develop antibodies to these therapies

25
Q

How do we monitor patients with Psoriasis?

A

Psoriasis Area Severity Index (PASI)

Dermatology Life Quality Index (DLQI)

26
Q

List some variations of Psoriasis?

A
  • Chronic plaque psoriasis
  • Guttate Psoriasis
  • Palmo-plantar Psoriasis
  • Scalp Psoriasis
  • Nail Psoriasis
  • Flexure or Inverse Psoriasis
  • Pustular Psoriasis
  • Erythrodermic Psoriasis
27
Q

How does chronic plaque Psoriasis tend to present?

A

Large symmetrical plaques on the extensor surfaces

Particularly the backs of elbows/arms

28
Q

How does guttate Psoriasis occur/present?

A

In kids/adolescents following a viral/bacterial infection

It may develop into chronic plaque Psoriasis

29
Q

How do we investigate and treat Guttate Psoriasis?

A

ASO titre/History for recent infection

UVB phototherapy if it doenst resolve

30
Q

How does Palmo-plantar Psoriasis occur/present?

A

associated with smoking and sterile inflammatory bone lesions

Large plaques on the palms and soles

31
Q

Why is scalp Psoriasis important?

A

It can often be missed in examination

And it can lead to alopecia

32
Q

How is flexural or inverse Psoriasis different?

A

Often lacks a scale

33
Q

How does pustular Psoriasis occur/present?

A

Tiny sterile pustules in the plaques

IT occurs when:

  • Pregant
  • Hypocalcaemic
  • Infected
  • On rapid steroid withdrawel
34
Q

Whats particularly bad about Erythrodermic Psoriasis

A

Presents with fever

Rapid onset generalised erythema and lesions (>80% of body) +/- pustule clusters

35
Q

How do you manage Erythrodermic Psoriasis?

A
  • Bloods (including excluding infection) [Elevated WCC]
  • IV access
  • Admit to hospital
  • Thick/greasy emollient
  • Fluid balance!!!
  • Find the trigger
  • Avoid steroids
  • Systemic or Biologic therapy