Psoriasis Flashcards
What is the pathophysiological mechanism of psoriasis?
T cell mediated autoimmune disease, abnormal infiltration of T cells causing release of cytokines (interleukins, TNF) and inducing increased keratinocyte proliferation
A patient has rash on extensor surfaces. What might be the cause?
psoriasis
Name two histological features of psoriasis
acanthosis (epidermal thickening) and parakeratosis (nuceli in stratum corneum)
- Hyperproliferation of keratinocytes, resulting in irregular thickening of epidermis= acanthosis 2. Loss of granular layer 3. Nuclei are retained in stratum corneum=parakeratosis 4. Inflammatory cell infiltration in dermis and epidermis
What are differences between psoriasis and atopic eczema?
less itchiness in psoriasis, can present at any age whereas atopic ezcema presents in childhood. Demarcation
Which diseases are linked to psoriasis?
metabolic syndrome, liver disease, alcohol misuse, depression, psoriatic arthritis
List three types of psoriasis?
plaque, guttate, pustular, erythrodermic, flexural
Patient with psoriasis has appendix removed. They develop psoriatic plaque around the scar. What is this known as?
Koebner phenomenon
What are classical clinical features of psoriasis?
salmon pink, demarcated, silvery scale, distribution is symmetrical, extensor surface pattern, thickened patch
If psoriasis hasn’t responded to topical treatment and UV therapy, what could you try next?
systemic therapy- immunosuppressants, oral retinoid, biologics
Which vitamin analogue can be used topically as first line treatment in psoriasis?
vitamin D= first line, vit A retinoid=not first line
In psoriasis, pin-point bleeding can occur if a scale is scraped off= Auspitz sign. Why does this occur?
capillaries in the dermis are close to the surface in psoriasis, tortuous, and numerous, thus is scale is scraped off then bleeding will occur as the most superficial capillaries are torn
Name four features of psoriatic nail involvement
pitting, onycholysis, subungal hyperkeratosis, roughened and discoloured nail surface
Name an example of a vit D analogue
calcitriol
What are advantages and disadvantages of vit D analogues?
Advantages- effective, clean, convenient. Disadvantages- greasy, skin irritation, need constant treatment
List three triggers for psoriasis?
stress, infections, skin trauma (kobner phenomenon), drugs, smoking
List three general signs of psoriasis
- Plaques
- Nail changes
- Seronegative arthritis
Describe the plaques that develop in psoriasis
symmetrical, demarcated, silvery scale, red plaque
Which parts of the body does psoriasis affect?
flexures, axillae, groin, scalp, behind ears, sacrum, navel
Name two features of psoriatic arthritis
Mono/oligo arthritis
Assymetrical polyarhtritis
Psoriatic spondylitis
Which infection is associated with guttate psoriasis?
strep
Which type of psoriasis may be localised to the palms and soles?
pustular
Which manifestation of psorasis is there severe systemic upset?
erythroderma and generalised pustular
List three differentials for psoriatic like lesions
eczema, tinea= ringworm, seborrhoeic dermatitis
List four aspects of psoriasis management
- Education- avoidance of triggers
- Emollients
- Topical therapy
- UV phototherapy
- Immunosuppressants
- Biologics
List two topical treatments for psoriasis
Vit D3 analogue- calcipotriol
steroids
retinoids
List three non-biologicals/immunosuppressants for psoriasis
methotrexate
ciclosporin
acetretin (vit A analogue)
List three biologicals used in psoriasis treatment
infliximab
etanercept
adalimumab
