Psoriasis Flashcards by Sophia Boyce

Describe psoriasis

Chronic, genetically determined, immune-mediated, inflammatory skin condition

How well did you know this?

Not at all

Perfectly

What is psoriasis usually characterised by?

Well-defined, red, scaly plaques

How well did you know this?

Not at all

Perfectly

Name the 8 types of psoriasis

Chronic plaque
Flexural
Acute guttate
Scalp
Palmoplantar
Nail
Pustular
Erythrodermic

How well did you know this?

Not at all

Perfectly

What is the most common type of psoriasis?

Chronic plaque

How well did you know this?

Not at all

Perfectly

What are the 2 unstable forms of psoriasis?

Pustular

Erythrodermic

How well did you know this?

Not at all

Perfectly

What is psoriasis caused by (pathophysiology)?

Overactivity of the immune system

How well did you know this?

Not at all

Perfectly

Epidermal infiltration by activated T cells and excessive production of what leads to psoriasis?

TH1 cytokines (esp TNF-alpha - linked to flares)

How well did you know this?

Not at all

Perfectly

Give the pathophysiological causes each for the erythema, and the plaques + scaling?

Erythema = vascular proliferation; capillary angiogenesis

Plaques + scaling = increased cell turnover

How well did you know this?

Not at all

Perfectly

What are the categories for causes/triggers of psoriasis?

Genetics
Environmental (stress)
Infection 
Drugs
Trauma
Sunlight (~10% it worsens; rest it helps)
Cigs/alcohol
HIV

How well did you know this?

Not at all

Perfectly

What types of infection can trigger psoriasis?

Strep

Candida

How well did you know this?

Not at all

Perfectly

What drugs can trigger psoriasis?

Lithium
ACEI
Beta-blockers
NSAIDs
Steroid withdrawal

How well did you know this?

Not at all

Perfectly

What is the koebner phenomenon?

Development/spread of patches of psoriasis as triggered by trauma (cut, bruise, burn etc)

How well did you know this?

Not at all

Perfectly

What is the usual rate of skin cell turnover vs rate in psoriasis?

4-5 weeks

3-5 days

How well did you know this?

Not at all

Perfectly

Is there a familial component to the development of psoriasis?

Yeah

1 parent = 14%; both parents = 41%

How well did you know this?

Not at all

Perfectly

Name some of the genes (3) thought to be associated with psoriasis?

HLA (human leukocyte antigens) Cw6, B13, B17

How well did you know this?

Not at all

Perfectly

What are 4 terms that describe the basic histology of psoriasis? Define them?

Hyperkeratosis = thickening of stratum corneum
Parakeratosis = keratinocytes with nuclei in stratum corneum
Hypogranulosis = nogranular layer
Psoriasiform hyperplasia = acanthosis (thickening of squamous cell) with elongated rete ridges

What are the neutrophils in stratum corneum in psoriasis histology called?

Munro’s microabscesses

What is the appearance of capillaries in psoriasis histology?

Dilated

What percentage of cases of psoriasis is chronic plaque?

90%

What complications can occur in severe chronic plaque psoriasis?

Cardiovascular health impacts; psycho-social impacts

How is chronic plaque commonly managed?

Topical treatments in primary care setting

How is guttate psoriasis usually developed?

Post-viral; usually self-limiting

What does guttate respond well to?

Phototherapy

What can guttate develop into?

Chronic plaque

Which type of psoriasis has been shown to have the greatest effect on patients quality of life?

Palmo-plantar

What is a differential diagnosis for scalp psoriasis?

Seborrheic dermatitis | Psoriasis scales are usually thicker/drier and tend to extend more beyond the scalp

Give the 2 pathognomic features of nail psoriasis?

1. Pitting | 2. Oncholysis

What is a distinctive feature of flexural/inverse psoriasis?

Lack of scales - just red, sharply demarcated plaque often at skin folds e.g. armpits

Describe the appearance of pustular psoriasis

Generalised red, tender patches with multiple small yellow pustules

How would you describe a patient who presented with a long history of chronic plaque, with a recent flareup and generalised erythema of the skin with fine scale along with pyrexia and low BP?

Erythrodermic psoriasis

What is erythrodermic psoriasis also known as?

'Red Man Syndrome' - >90% body surface involved

Where should erythrodermic psoriasis be managed?

Hospital

Give 3 differentials for psoriasis

``` Seborrhoeic dermatitis (esp scalp, face) Lichen planus (check forearm, oral mucosa) Mycosis fungoides (older PT, sudden onset - biopsy) ```

Give the first line treatment plan for psoriasis

``` Topical steroids (flexural/genital area) Vit D3 analogues (calcioptriol) +/- steroids Tar creams + Emollients (to smooth skin) + Salicylic acid (to remove plaques) ```

Give the 2nd line treatment for psoriasis

Dithranol/Anthralin - slower onset of action and has various side effects e.g. staining of skin/clothes and cant be applied to face/genitals

Give some 3rd line options for psoriasis treatment

- UVB Phototherapy - Acitretin (teratogenic, impairment of LFTs/lipids) - Methotrexate (also for joint/nail involvement, improvement in 2-3 months) - Cyclosporin - Inpatient Tar (crude coal tar in zinc ointment) - Biologics - qualifying criteria, cost - Retinoids, immunosuppressants

What is the treatment plan for ERYTHRODERMIC psoriasis

ADMIT Fluid balance Bloods/IV access Thick greasy ointment emollients

What are the 2 criteria for monitoring of psoriasis

PASI (psoriasis area severity index) | DMQI (dermatology life quality index) - more general

In what percent of psoriasis patients does it progress to arthritis?

5-10%