Drug Eruptions and the Skin in Systemic Disease Flashcards
Causes and features of maculopapular drug eruptions (3)
penicillins, cephalosporins, anti-epileptics
generalised erythematous macules and papules +/- fever and raised eosinophils
eruption w/i 2wks of taking drug
Causes and features of urticarial eruptions (4)
wheals+/- angiodema and anaphylaxis
rapid onset after taking drug
immune (IgE mediated):
- penicillin
- cephalosporin
non-immune (mast cell degranulation):
- morphine
- codeine
- NSAIDs
- contrast
Presentation of erythema multiforme (2)
symmetrical target lesions on palms, soles and limbs
occur 1-2wks after insult
Causes of erythema multiforme (3)
INFECTIONS: main cause-HSV and mycoplasma
drugs-SNAPP:
- sulphonamides
- NSAIDs
- allopurinol
- phenytoin
- penicllin
idiopathic
Features of SJS (2)
more severe form of erythema multiforme
blistering mucosa: conjunctival, oral and genital
Features of TEN (3)
severe form of SJS
nearly always a drug reaction
increased risk in HIV+ve patients
Presentaiton of TEN (3)
severe mucosal ulceration
widespread erythema followed by epidermal necrosis w. loss of large sheets of epidermis
> dehydration
Rx and prognosis of TEN (2)
Rx w. Dexamethasone +IVIg
30% mortality rate
Features and causes of erythema nodosum (5)
painful, blue-red lesions on anterior shins
causes-3Ss:
- sarcoid
- sulphonamides
- strep
also: IBD, TB, bechet’s, OCP
Features of pyoderma gangrenosum (3)
wide, deep ulceration w. violaceous border, purulent surface and undermined edge
commonly occurs on legs
heals w. cribriform/pitted scars
Assoc. of pyoderma gangrenosum (5)
IBD
AIH
RA
Wegener’s
Leukemia
Rx of pyoderma gangrenosum
high-dose systemic steroids
Features and association of vitilligo (3)
chalky, white patches w. hyperpigmented borders
itch under sunlight
assoc. w. autoimmune conditions
Features of livedo reticularis (3)
persistent, mottled, red-blue lesions which don’t blanch
found mainly on legs
triggered by cold
Causes of livedo reticularis (4)
idiopathic
vasculitis: SLE, RA, PAN
obstruction: antiphospholipid, cryoglobulinaemia
Sneddon’s syndrome: Livedo reticularis+CVAs