Skin conditions: Psoriasis Flashcards
Define Psoriasis.
Psoriasis is an autoimmune condition that causes thick, scaly plaques to form on the skin. In psoriasis patients usually experience periods of flare ups and remission.
Which demographics are most likely to be affected by psoriasis?
Development usually peaks in the late teens to early 30s and then from between 50 - 60 years.
The condition affects men and women equally.
What percentage of the UK population suffers with psoriasis?
2-3%
What causes psoriasis?
Normal keratinocytes take 3 weeks to one month to migrate from the stratum basal to the stratum corneum. Whereas in psoriasis keratinocytes migrate in 3-4 days meaning that the rate of proliferation and migration of keratinocytes outweighs the rate at which they are shed leading to the production of plaques (thickened keratinocytes) on the skin. Inflammatory cells are then increased in all layers of the skin.
What is the genetic predisposition associated with psoriasis?
Approximately 1 in 4 children with a parent with psoriasis will go on to develop it.
However it is relatively complex as it involves multiple genes in its development.
What are some of the trigger events which cause those with underlying genetics to develop psoriasis?
Usually an external trigger such as:
Stress
Infection (Streptococcal infection)
Injury to skin
Virus (HIV or HPV)
Withdrawal of corticosteroids
Disease can be precipitated by NSAIDS, Lithium, Beta blockers
What is the clinical presentation of plaque psoriasis?
Red, sore, itchy, plaques that have white or silvery scales.
These plaques are well demarcated from the rest of the skin.
What is a complication of plaque psoriasis?
Psoriatic arthritis
Where does psoriatic plaques usually occur?
Palms
Soles
Where the skin touches the skin
Why is the skin read underneath the scales?
Due to increased vascularisation in order to try and compensate for the increased proliferation of keratinocytes.
What is the clinical presentation of scalp psoriasis?
Build up of thick scaly skin which has lead to dandruff like flakes on the scalp.
If severe it can thinning of the hair
Which part of the head does scalp psoriasis specifically occur?
Hairline
Forehead
Neck
Ears
What is guttate psoriasis?
Widespread psoriasis often occurring on the back, torso and limbs and presents as little raindrops that are bright pink or red on fair skin or more darkening on dark skin.
It usually clears up by itself.
What triggers guttate psoriasis?
Strep throat
What demographics often experience guttate psoriasis?
Children or young adults
What is the clinical presentation of pustular psoriasis?
It is the formation of small white or yellow fluid filled blisters on top of red or darkened skin.
Upon bursting these crust over.
Can be quite painful.
Where does pustular psoriasis usually occur?
On the palms of the hands or the soles of the feet
If a patient presents with pustular psoriasis what is the appropriate management?
Referral to a dermatologist, especially if it is widespread on the body this requires urgent medical attention