Card Set Information
what is the incidence of psoriasis worldwide?
where does psoriasis affect?
what is sex preponderance of psoriasis?
what is peak age onset of psoriasis?
2nd and 3rd decade
what is the main pathogenesis of psoriasis?
production of keratinocytes is increased 28 fold!
which WBC type mediates psoriasis?
T cell - so its a Rx target
what is parakeratosis?
when keratin layer have NOT lost their nuclei
what is acanthosis?
thickening of epidermis
what are the triggers of psoriasis? (8)
infection - strep (guttate), HIV
trauma - koebner
drugs - steroids
endocrine - pregnancy, hypocalcaemia
what are the 5 types of psoriasis?
sebo-psoriasis (looks like seborrheic dermatitis)
pustular - generalised/localised
which 2 types of psoriasis are emergencies?
pustular - generalised/localised
how would you describe plaque psoriasis?
well defined plaque - FLAT, ELEVATED
on extensor surface
thick silvery whicte scale
where are common sites for chronic plaque psoriasis?
what are the 4 nail signs of psoriasis?
: lifting of nail plate off nailbed
: small depressions in nail plate
3. longitudinal ridging
4. subungal hyperkeratosis
what are the 5 types of psoriatic arthropathy?
2. symmetric polyarthritis
4. destructive (arthritis mutilans)
5. axial arthritis
what causes guttate psoriasis?
post strep throat infection
who gets guttate psoriasis?
describe appearance of guttate psoriasis?
shower of scattered discrete lesions
up to 1cm
round or slight oval
small plaques on trunks/limbs
what is Rx of guttate psoriasis?
what are the 2 types of pustular psoriasis?
localised eg palmoplantar
generalised - life threatening!
what are features of palmoplantar pustular psoriasis?
palms and soles studded with sterile pustules on erythematous base
what are features of generalised pustular psoriasis?
indicates severe, unstable psoriasis
what can precipitate pustular psoriasis?
use of steroids
why is generalised pustular psoriasis an emergency?
what is Rx of Gen pustular psoriasis? 3 aspects
1. admit, ITU maybe needed
2. greasy emollients, iv support, avoid/treat infection
3. systemic therapy - acetretin or ciclosporin
how would you describe erythrodermic psoriasis?
skin becomes universally red with scaling
what are symptoms of erythrodermic psoriasis?
skin hot and uncomfortable
what are the complications of erythrodermic psoriasis?
heat loss - hypothermia
infection as barrier loss
what is Rx for erythrodermic psoriasis?
systemic - acetretin/ciclosporin immunosupp
what are the 5 step treatments for psoriasis?
2. topical agents
4. systemic agents
5. biological agents
what are the 4 different topical treatments for psoriasis?
what are the 2 types of phototherapy, difference?
narrow band UVB
pUVA=UVA plus psoralen
what is puva?
psoralen + UVA treatment
psoralen is taken orally to photosensitise skin then expose to UVA
P allows a lower dose of UVA to be used
what are the systemic treatments for psoriasis based on?
t cell suppression
give 5 eg of systemic Rx for psoriasis?
: acetretin- reduce cell turnover
: methotrexate, ciclosporin, hydroxyurea
what are the biological Rx for psoriasis?
anti TNF - monoclonal antibody
what is lichen planus? what does it affect?
affects skin, mucous membranes, nail, hair
what are the 5 Ps to describe lichen planus?
where does lichen planus tend to affect?
: flexor surfaces - wrist, forearm
: white striae
what does LP in the mouth look like?
reticulated lacy white patter
what does LP in the mouth increase the risk of?
what is the topical Rx for LP?
what are the systemic Rx for LP? (4)
what is the natural history for LP?
most resolve in 1-2 years
what is the diagnosis for an asymptomatic man with a large patch on his trunk followed by a rash 1 week later?
what is that patch called?
who does pityriasis rosea affect and what is cause?
viral cause? seasonal variation
what does the actual rash of PR look like?
oval erythematous papules
some scale in middle
what kind of pattern may PR form and why?
lesions follow lines of dermatomes
xmas tree pattern
what is Rx of PR?
no Rx usually
if itchy then antihistamine (as the histamine is what makes itch)