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Dermatology (Year 2 GM) > Psoriasis > Flashcards

Flashcards in Psoriasis Deck (27):
1

What causes the development of psoriasis?

Polygenic predisposition and environmental triggers

Family history is very common

2

What HLA is associated with psoriasis?

HLA-Cw6 (Chromosome 6)

3

What are examples of environmental triggers?

Infection

Drugs

Trauma

Sunlight

4

What is the involvement of the immune system in psoriasis?

Stressed keratinocytes - activation of dermal dendritic cells

These dermal dendritic cells travel to the lymph nodes and present antigen to niave T cells 

 

T cells differentiate into Th 1, 17 and 22

 

Leads to psoriatic dermis and plaque formation

 

Keratinocyte proliferation because interleukins and TNF alpha amplify inflammatory cascade

VEGF causes angiogenesis

Neutrophils in acute, active, pustular phase

 

The cell cycle is reduced from 28 days to 3-5 days

5

What is the histology of psoriasis?

•Hyperkeratosis (thickening of stratum corneum)

•Neutrophils in stratum corneum (munro’s microabcesses)

•Psoriasiform hyperplasia: Acanthosis (thickening of squamous cell layer) with elongated rete ridges

•Dilated dermal capillaries

•T cell infiltration

6

Describe the skin in psoriasis

–Sharply demarcated, erythematous, papulosquamous plaques

–Numerous small, widely disseminated papules & plaques

Pustules

Erythroderma

 

7

Describe the nails in psoriasis

–Onycholysis, pitting, oil spots

 

Onchylosis: is a common medical condition characterized by the painless detachment of the nail from the nail bed, usually starting at the tip and/or sides.

8

What is chronic plaque psoriasis?

Chronic

Salmon coloured plaques

Found on extensor surfaces and is extensive

9

What is Guttate psoriasis?

Acute onset generalised rash

Papules

Affects children and adolescents

Papules worse on trunk and proximal extremities

Check ASO titre

Can be triggered by viral or bacterial infections

It may resolve or it may even trigger chronic psoriasis

10

What form of psoriasis is associated with skin on the palms and soles appears thick, scaly and red with yellowish brown lesions at the edges?

 

Palmo-plantar Psoriasis

11

What type of psoriasis is associated with severe dandruff - pink hyperkeratotic plaques at her scalp

Scalp psoriasis

12

What type of psoriasis causes pitting in the nails?

Nail psoriasis

13

What type of psoriasis is likely to occur bilaterally in the axilla?

 

With NO scale

Flexural / inverse psoriasis

14

What can trigger or even superinfect flexural psoriasis?


Can be triggered or superinfected by localised dermatophyte, candidal or bacterial infection – these are also differential diagnoses

15

What type of psoriasis has generalised red tender patches with multiple yellow pustules?

Pustular psoriasis

 

Pustules are sterile - sometimes features systemic symptoms

16

What causes pustular psoriasis?

Pregnancy

Rapid taper / stoppping steroids

Hypocalcaemia

Infection

17

Erythrodemic psoriasis is often a complication of psoriasis - what is the differential?

Red man syndrome - drug reaction to vancomycin

18

What is the diagnosis of psoriasis?

Skin biopsy

19

What are the differential diagnosis' for psoriasis?

•Seborrhoeic dermatitis

•Lichen planus

•Mycosis fungoides

20

What is the treatment of psoriasis?

Most treated in primary care - less than 30 % are referred to dermatology

 

Emollients (creams vs ointments)

Soap substitutes

Vitamin D3 anologues - these inhibit epidermal proliferation

Coal tar creams

Topical steroid 

Salycilic acid (keratolytic) - this is a descaling agent

21

What are the available treatments in dermatology?

•Crude Coal Tar (inpatient or day treatment)

•Dithranol: since 1916. Can burn.

•UVB Phototherapy (not the same as sunbed)

–Guttate

22

What systemic disease is associated with psoriasis?

–5-30% develop psoriatic arthritis

–Psychosocial implications

–Metabolic syndrome – more susceptible to having cardiovscular complications

23

What are the systemic treatments of psoriasis?

Retinoid - Acitretin

–Teratogenic, LFTs, lipids

Immunosuppression

–Methotrexate

•Can treat PsArthritis

•Max improvement 8-12 weeks

–Ciclosporin

•Renal, cancer risk

•Biologic Therapies

–Qualifying criteria, cost

–Anti-TNF: Etanercept, infliximab, adalimumab

–IL-12,23: Ustekinumab

–Patient can form antibodies to biologic

24

Future treatments

•Targeted biologics

•IL-17,20,22

•Kinase inhibitors

 

•Ethical / cost dilemmas

–Adalimumab ~£9000 per year (£225000 for 25 years)

–Methotrexate ~£12.50 per year

25

What is the treatment of Erythrodermic Psoriasis?

•Admit

•FLUID BALANCE

•Bloods / IV access

•Thick greasy ointment emollients

 

•?Systemic or biologic treatment

•?Trigger

26

What can be used to monitor the progress of psoriasis?

•Psoriasis Area Severity Index (PASI)

–Surface area, plaque colour, thickness, scale

•Dermatology Life Quality Index (DLQI)

–QOL in last 1 week

27