Acute and Emergency Dermatology Flashcards
What % of body mass does skin make up in the average person?
10%
Consequences of failure of the skin
Sepsis Hyper and hypo thermia Protein and fluid loss Renal impairment Peripheral vasodilation that can occasionally lead to cardiac failure
Definition of erythroderma
Any inflammatory skin disease affecting > 90% of the total skin surface
Causes of erythroderma
Psoriasis Eczema Drugs Cutaenous lymphoma Hereditary disorders
Treatment of erythroderma
ITU / burns unit Remove any offending drugs Careful fluid balance Good nutrition Temp regulation Emollients - 50:50 liquid paraffin : white soft paraffin Oral and eye care Anticipate and treat infection Manage itch Treat underlying cause
When do drug reactions commonly occur?
1 - 2 weeks after drug
Within 72 hours if rechallenged
Mild drug reactions affecting the skin causes what?
Morbilliform exanthem
Severe drug reactions affecting the skin causes what?
Erythroderma
Steven johnstons syndrome / toxic epidermal necrolysis
DRESS
Which of SJS and TEN is less severe?
SJS
What drugs can cause SJS and TENS?
Antibiotics
Anticonvulsants
Allopurinol
NSAIDs
Presentation of SJS
Fever Malaise Arthralgia Rash - maculopapular - target lesions - blisters Mouth ulceration - greyish white membrane - haemorrhagic crusting Ulceration of other mucous membranes
Definition of arthralgia
Joint pain
Presentation of TEN
Prodromal febrile illness Ulceration of mucous membranes Rash - may start at macular, purpuric or blistering - rapidly becomes confluent - desquamation > 30% BSA Nikolsky's Sign may be +ve
Definition of prodromal
Relating to or denoting the period between the appearance of initial symptoms and the full development of a rash and fever
What is desquamation?
Sloughing off large areas of epidermis
Definition of Nikolsky’s sign
Rub the skin and lose the skin surface over the area that you rub
Treatment of SJS / TEN
Stop drug Supportive Possible - high dose steroids - IV immunoglobulins - anti TNF therapy - ciclosporin
Mortality of SJS
10%
Mortality of TEN
30%
What scoring system is used for SJS / TEN?
SCROTEN
What does SCROTEN look at?
Age > 40 Malignancy HR > 120 Initial epidermis detachment >1-% Serum urea >10 Serum glucose >14 Serum bicarbonate <20%
Long term complications of SJS / TEN
Pigmentary skin changes Scarring Eye disease and blindness Nail and hair loss Joint contractures
What is erythema multiforme?
Hypersensivity reaction usually triggered by infection.
Abrupt onset of up to 100s of lesions over 24 hours
2 most common causes of erythema multiforme
HSV most common
Then mycoplasma pneumonia
Presentation of erythema multiforme
Abrupt onset of up to 100s of lesions over 24 hours
Distal -> proximal
Palms and soles
Mucosal surfaces (EM major)
Evolve over 72 hours
- pink macules, become elevated and may blister in the centre
- target lesions
How long does erythema multiforme take to resolve?
Over 2 weeks
What does DRESS stand for?
Drug Reaction with Eosinophilia and Systemic Symptoms
Mortality of DRESS
10%
When does DRESS occur?
Onset 2 - 8 weeks after drug exposure