Psoriasis Flashcards
(37 cards)
What is psoriasis?
systemic, immune-mediated, inflammatory skin disease
Typically has a chronic relapsing-remitting course
May have nail + joint (psoriatic arthritis) involvement
Describe the aetiology of psoriasis
Multifactoral
Genetic predisposition
Trigger of inflammatory response (infection, irritation, drugs)
4 subtypes of psoriasis
Plaque (most common)
Pustular (2nd most common)
Guttate
Erythrodermic
List 5 conditions associated with psoriasis
Psoriatic arthropathy
Metabolic syndrome
Cardiovascular disease
VTE
Psychological distress
4 features of plaque psoriasis
Well demarcated red, scaly patches
Symmetrical distribution, extensor surfaces
Psoriatic nail changes
Koebner phenomenon
Give 5 features of psoriatic nail changes
Affect fingers + toes
Pitting
Onycholysis
Subungal hyperkeratosis
Loss of nail
4 features of guttate psoriasis
Transient (often resolves after several months)
Widespread, erythematous, fine, scaly papules (water drop appearance)
Scattered on trunk + limbs
Often triggered by Streptococcal infection
4 features of erythrodermic psoriasis
Diffuse, widespread severe psoriasis affecting >90% of body surface area
Pain, irritation, + severe itching
Malaise , fever + dehydration
Skin feels hot + uncomfortable
Describe development of erythrodermic psoriasis
Can develop gradually from chronic plaque psoriasis or appear abruptly, (even in mild psoriasis)
May be precipitated by systemic infection, irritants, phototherapy
3 features of localised pustular psoriasis
aka. Palmo-plantar pustulosis
Crops of sterile pustules on hand(s)/ feet
A/w thickened, scaly, red skin that easily develops painful fissures
3 features of generalised pustular psoriasis
RARE + SEVERE form of pustular psoriasis
Reccurent flares of widespread sterile pustules with erythematous painful skin
Involvement of mucosa + systemic features
What is koebner phenomenon?
New skin lesions of pre-existing dermatosis in areas of cutaneous injury in otherwise healthy skin
List 4 exacerbating factors of psoriasis
Trauma
Alcohol
Drugs
Withdrawal of systemic steroids
List 6 drugs that may exacerbate psoriasis
B-blockers
Lithium
Antimalarials: Chloroquine + hydroxychloroquine
NSAIDs
ACEi
Infliximab
Dx of psoriasis
Clinical
Biopsy if unsure
Which forms of psoriasis are potentially life-threatening medical emergencies?
Generalised pustular psoriasis
Erythrodermic psoriasis
Describe the step-wise management for plaque psoriasis
- Potent CS OD plus vitamin D analogue OD, applied separately (1 AM, 1 PM) for up to 4w
- If no improvement after 8w offer: vitamin D analogue BD
- If no improvement after 8-12w offer either:
a potent CS applied BD for up to 4w, or
a coal tar preparation applied OD-BD
Short-acting dithranol can also be used
Regular emollients may help reduce scale loss + reduce pruritus
Give an example of a potent corticosteroid and vitamin D analogue to use in plaque psoriasis
Hydrocortisone
Calcipotriol, calcitriol + tacalcitol
When should a patient with psoriasis seek urgent medical advice?
If they experience unexplained joint pain or swelling: may be a sign of psoriatic arthritis; requires specialist referral.
What treatment options may be offered in secondary care management of plaque psoriasis?
Phototherapy
Oral Methotrexate / Ciclosporin/ Biologics
What type of phototherapy is used in treatment of plaque psoriasis?
Narrowband ultraviolet B light
3x per week
Describe management for scalp psoriasis
Potent topical CS OD for 4w
If no improvement after 4w; either use a different formulation of the potent CS (e.g. a shampoo or mousse) +/or a topical agent to remove adherent scale (e.g. agents containing salicylic acid, emollients + oils) before applying CS
Describe management of face, flexural and genital psoriasis
Mild-mod potency CS applied OD-BD for max 2w
Why should steroids only be used on the scalp, face and flexures for limited periods?
Particularly prone to steroid atrophy
