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
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
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 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
