Psoriasis Flashcards
What is psoriasis?
it is a chronic immune-mediated inflammatory condition
What % of the population has psoriasis?
Which age and gender are more likely to be affected?
- prevalent in 2% of the population
- males and females affected equally
- occurs at any age but has a bimodal distribution with peaks at 15-25 and 50-60 years
Is psoriasis present all the time?
Yes it is chronic and long term but it can come and go, with flare ups
What structures, other than the skin, are commonly involved in psoriasis?
- it can affect the joints in psoriatic arthritis
- it can affect the nails in approximately half of patients
What causes psoriasis?
What are the stages involved?
it is caused by an interplay between genetic predisposition & environmental factors that causes structural changes in the skin
- epidermal hyperproliferation (thickening) producing overlying scale in stratum corneum
- inflammatory cells in the epidermis
- angiogenic response
What factors usually trigger flare ups in psoriasis?
- trauma or skin damage
- stress
- infection
- alcohol
- smoking
- some medications
What medications trigger psoriasis flare ups?
- beta blockers
- antimalarials
- lithium
- NSAIDs
- withdrawal of oral steroids
What are the general clinical features of psoriasis?
- defined red, scaly, itchy patches
- typical plaques of red areas with silvery-white scales
- lichenification and fissures can form and bleed from scratching
- can be localised or generalised, acute or chronic, with or without arthritis and nail involvement
What do psoriatic nails look like?
- pitting
- thickening
- nail plate lifting from the bed
- discolouration under the nail
- onycholysis
What is onycholysis?
painless detachment of the nail from the nail bed, usually starting at the tip and/or sides
What is the Koebner phenomenon?
psoriasis occuring at the site of skin injury or scarring
What are the 5 different types of psoriasis?
- chronic plaque
- guttate
- palmoplantar
- flexural
- pustular
What is the most common type of psoriasis?
chronic plaque psoriasis
How does chronic plaque psoriasis usually present?
- varying sized plaques usually present on the knees, elbows, scalp and trunk
- may be localised or generalised (limbs, trunk & scalp)
- psoriasis of the scalp and nails often occur
What type of treatment is usually needed for chronic plaque psoriasis?
it is persistent so often requires systemic treatment as well as topical treatment
How does guttate psoriasis present?
- small plaques spread widely over the trunk, arms and legs
- plaques are tear drop shaped
- it appears quickly, within a day or two
Who is usually affected by guttate psoriasis?
it affects mostly children and young children
What usually triggers guttate psoriasis?
it can be triggered by Streptococcus and so may follow on from a Streptococcal throat infection
it has a chance of resolving and dissappearing completely
antibiotics may be needed for the streptococcal infection
What part of the body is usually affected in palmoplantar psoriasis?
How does it present?
- mostly on the palms of the hands and feet
- coverage may be small or complete
- it is often symmetrical
What is palmoplantar psoriasis associated with?
strongly associated with psoriatic arthritis and nail disease
Where is flexural psoriasis found?
What does it look like?
- present in flexures (body folds) and around the genitals, armptis, groin & breast folds
- red and well defined but may be more shiny than scaly
What is flexural psoriasis usually combined with?
it is often combined with candida yeast colonisation
What does pustular psoriasis present like?
What other symptoms may be present?
- plaques contain pus-filled spots
- sudden flares of pustules may occur in combination with other symptoms such as fever, headache, anorexia & nausea
- may require hospitalisation if generalised
What are possible triggers for development of pustular psoriasis?
- infection
- certain drugs
- sudden corticosteroid cessation
What are the different treatment options for psoriasis?
- emollients
- topical steroids
- coal tar preparations for bathing, shampooing and applying as a cream
- dithranol
- vitamin D analogues
What types of emollients are used in psoriasis and why?
emollients with salicylic acid as they may help to lessen the scaling
they should be applied often and used as a soap substitute
Why are vitamin D analogues used in psoriasis?
What are they often combined with?
- vitamin D analogues, such as calcipotriol, reduce epidermal proliferation and scale
- they can cause irriation so are often combined with topical steroids
What is involved in phototherapy for psoriasis?
specific wavelengths of light are shone at the skin and this has an immunosuppressive effect
How often is phototherapy performed for psoriasis?
it is performed 3 times a week for up to 10 weeks
What are the systemic treatments for psoriasis and who is offered these?
- oral retinoids, such as acitretin
- immunosuppressants such as ciclosporin and methotrexate
- biologic treatments
offered to patients with severe disease
When does acitretin tend to be used?
it is effective when there is nail involvement and is often combined with phototherapy
What is meant by psoriasis being a multisystemic disease?
due to the inflammatory nature, other conditions are associated with psoriasis and it is not uncommon for patients to suffer with other related diseases
What are the associated diseases with psoriasis?
- psoriatic arthritis & spondyloarthropathies
- IBD, uveitis & coeliac disease
- obesity, hypertension, CVD and T2 diabetes
- depression
