4) Derm emergencies Flashcards
What is erythroderma?
involvement of over 90% of the skin with an inflammatory or neoplastic process. Essentially skin failure
What diseases can cause erythroderma?
eczema, psoriasis, drug eruptions, skin lymphomas
When it is associated with exfoliation what is it known as?
exfoliative dermatitis
S+S of erythroderma?
warm to touch itchy scaling 2-6 days after redness scalp may scale LN may swell
Complications of erythroderma?
loss of fluid, secondary infection, heat loss, catabolic state, high output CF
what does biopsy show in erythroderma?
often unhelpful but important to rule out CTCL
Management of erythroderma?
admit
supportive care, keep warm and watch for infection. Give supportive nutrition. Active treatment generally not required so bland emoliants are used. May manage depending on caue after initial stages
What is staph scalded skin?
Red blistering rash that looks like a scald. Caused by the release of exotoxins A and B from gp II staph.
WHat do the exotoxins do in staph scalded skin?
THey bind to desmoglein 1 and break it up so that the cells unstich
What is another issue with all the toxin in staph scalded skin?
excreted by the kidney so can risk renal failure
Who does staph scalded skin tend to happen in?
kids under 5, get lifelong abs to the toxins that make it v unlikely when older
S + S of staph scalded skin?
usually fever, irritability, widespread redness
fluid filled blister form over a day or so
tissue paper wrinkling of skin, large blister in armpits and groin goes to everywhere
What is nikolsky s sign?
gentle storkes of skin can cause exfoliation- top layer peels off in sheets
Where do you tend to get blisters in neonates in staph scalded skin?
around the diaper area and umbilicus
How do you diagnose staph scalded skin?
Hx and Ex, tzanck smear, biopy (damage at granular layer), bacterial culture
treatment of staph scalded skin?
IV abx (fluclox), vanc if supect MRSA. supportive treatment, para, fluid balance, incubator for newborns
What is TEN?
full thickness epidermal loss. SJS and TEN are now thought to be part of a spectrum. rare, acute potentially fatal skin reaction in which there is sheet like skin and mucosal loss.
Who is TEN more common in?
slightly more in females, 100x more common in HIV
What is the likely cause? what type of drugs are more likely to cause it?
Almost always drug reaction sulphonamides, penicillins, cephalosporins, chloramphenicol anticonvulsant allapurinol nsaids/para
What are the biochemical causes of TEN?
cytokines have been implicated including perfrin/granzyme, fas/fasL. and tnf a. granule mediated exocytosis via perforin and granzyme B also implicated
CLincial hx of TEN?
Usually develops within the first week of abx, 2 months with anticonvulsant. prodromal urti preceeds. abrupt onset of red tender rash. Starts on trunk and spreads rapidly but rarely affects scalp, palm or soles.
What are the lesions like in TEN?
macules
difuse erythema
targetoid
blisters- converge to form sheets of detachment
Do you get mucosal involvemen in ten?
yes at least 2 and prominent/severe
Complications of SJS/TEN?
10% mortality, 30% for TEN infection dehydration ards shock dic
Dx of sjs/ten?
SJS is diagnosed clinically and classified by skin detachment
elevated granulysin is predictive in early drug eruption
skin biopsy usually required
keratinocyte necrosis, full thickness epidermal necrosis, minimal inflammation
will be anaemic, neutropenia is a bad prognostic sign
What is SCORTEN?
predictive of mortality
>40 malignancy HR>120 detachment >10% urea >10 glucose >14 bicarb>20
more than 5 has a 90% mortality
1 has 3.2
Difference between SJS and TEN
SJS- detachment < 10%
TEN- >30%
DD of SJS/TEN?
SSSS Erythema multiforme mycoplasma bullous sle paraneoplastic pemphigus
Management of SJS/TEN?
STOP DRUG, ADMIT TO ICU/BURNS
Supportive: fluid, temp, positive pressure, good nursing
topical antisepics (NOT SILVER)
care for eyes, mouth, catheter, abx if infection, vte prophylaxis
systemic management for SJS/TEN?
controversial
IVIG inhibits apoptosis but nothing has been shown to be effective really and trials hard as nubers small
