Acute and Emergency Dermatology Flashcards
What is the largest organ in the body?
Skin
Consequences of skin failure relates to function, what does failure of the skin to be a mechanical barrier to infection cause?
Sepsis
Consequences of skin failure relates to function, what does failure of temperature regulation cause?
Hypo or hyper-thermia
Consequences of skin failure relates to function, what does failure of the skin to balance fluid and electrolytes lead to?
Protein and fluid loss
Renal impairment
Peripheral vasodilation
What is erythroderma?
Descriptive term rather than a diagnosis:
- “Any inflammatory skin disease affecting >90% of the total skin surface”
What are some causes of erthroderma?
- Psoriasis
- Eczema
- Drugs
- Cutaneous lymphoma
- Hereditary disorders
- Unknown
What are the principles of erythroderma management?
- Remove any offending drugs
- Fluid balance
- Good nutrition
- Temperature regulation
- Oral and eye care
- Anticipate and treat infection
- Manage itch
- Disease specific therapy, treat underlying cause
What is an example of a mild drug reaction?
Morbiliform exanthema
What is morbiliform exanthema?
Rose-red flat (macular) or slightly elevated (maculopapular) eruption, showing circular or elliptical lesions varying in diameter from 1 to 3 mm, with healthy-looking skin intervening
What are examples of severe drug reactions?
- Erthroderma
- Stevens Johnson Syndrome (SJS)
- Toxic epidermal necrolysis (TEN)
- DRESS
What does SJS stand for?
Stevens Johnson Syndrome
What does TEN stand for?
Toxic epidermal necrolysis
What drugs can SJS or TEN be secondary to?
- Antibiotics
- Anticonvulsants
- Allopurinol
- NSAIDs
What percentage of epidermal detachment occurs with SJS?
<10%
What percentage of epidermal detachment occurs with TEN?
30%
Which of SJS and TEN affects a larger surface area?
TEN
What are the clinical features of SJS?
- Fatigue, malaise, arthralgia (pain in a joint)
- Rash
- Maculopapular, target lesions, blisters
- Erosions covering <10% of skin surface
- Mouth ulceration
- Greyish white membrane
- Haemorrhagic crustings
- Ulceration of other mucous membranes
What are the clinical features of TEN?
- Often presents with prodromal febrile illness
- Ulceration of mucous membranes
- Rash
- May start as macular, purpuric or blistering
- Rapidly becomes confluent
- Nikolsky’s sign may be positive
What is the management of SJS/TEN?
- Identify and stop culprit drug as soon as possible
- Supportive therapy
What is the prognosis of SJS/TEN?
SJS - 10% mortality
TEN - 30% mortality
What scale is used to determine how severe SJS or TEN are?
SCORTEN
What does a greater SCORTEN score increase?
Mortality
What does SCORTEN scale consider?
What are some long term complications of SJS/TEN?
- Pigmentary skin changes
- Scarring
- Eye disease and blindness
- Nail and hair loss
- Joint contractures
What is erythema multiforme?
Hypersensitivity reaction usually triggered by infection
What infections is erthema multiforme most commonly associated with?
HSV then myoplasma pneumonia
What is the clinical presentation of erythema multiforme?
Abrupt onset of up to 100s of lesions over 24 hours:
- Distal to proximal
- Palms and soles
- Mucosal surfaces
- Evolve over 72 hours
- Pink macules, become elevated and may blister
What is the treatment for erythema multiforme?
Self limiting and resolves over 2 weeks
Symptomatic and treat underlying cause
What does DRESS stand for?
Drug reaction with eosinophilia and systemic symptoms
What is the mortality of DRESS?
Up to 10%
When does DRESS occur after the drug exposure?
Onset 2-8 weeks after drug exposure
What is the clinical presentation of DRESS?
Fever
Widespread rash
Eosinophilia
Deranged liver function
Lymphadenopathy
Maybe other organ involvement
What is the treatment of DRESS?
- Stop causative drug
- Symptomatic and supportive
- Systemic steroids
- With or without immunosuppression or immunoglobins
What is pemphigus?
Rare skin disorder characterized by blistering of your skin and mucous membranes
Antibodies targeted at desmosomes
What is the clinical presentation of pemphigus?
Flaccid blisters that rupture very easily are seen in the skin
Intact blisters may not be seen
Nikolsky’s sign may be present
Commonly affects mucous membrane
Ill defined erosions in mouth
Where does pemphigus commonly affect?
Face, axillar and groins
What is pemphigoid?
Rare autoimmune disorder that can develop at any age, including in kids, but that most often affects the elderly. Pemphigoid is caused by a malfunction of the immune system and results in skin rashes and blistering on the legs, arms, and abdomen
What is the clinical presentation of pemphigoid?
Intact epidermis forms roof of blister
Blisters are usually tense and intact
In pemphigoid what are antibodies direct at?
Dermo-epidermal junction
Compare and contrast pemphigus and pemphigoid?
Which of pemphigus and pemphigoid is more common?
Pemphigoid
Which of pemphigus and pemphigoid affects older patients?
What is the treatment of pemphigus?
Systemic steroids
Dress erosions
Supportive therapies
What is the treatment of pemphigoid?
Topical steroids may be sufficient if localised
Systemic usually required if diffuse
What are some different kinds of psoriasis?
Erythrodermic psoriasis
Pustular psoriasis
What are common causes of erythrodermic and pustular psoriasis?
Infection
Sudden withdrawal of oral steroids or potent topical steroid
What is the clinical presentation of erythrodermic and pustular psoriasis?
Rapid development of generalised erythema with or without clusters of pustules
Fever
Elevated WCC
What is the treatment of erythrodermic and pustular psoriasis?
Exclude underlying infection, bland emollient and avoid steroids
Often require initiation of systemic therapy
What is eczema herpeticum?
Disseminated herpes virus infection on a background of poorly controlled eczema
What is the clinical presentation of eczema herpeticum?
Monomorphic blisters and “punched out” erosions
Which are painful but not itchy
Fever and lethargy
What is the treatment of eczema herpeticum?
- Dose of aciclovir
- Mild topical steroid if required to treat eczema
- Treat secondary infection
- Ophalmology input if peri-ocular disease
In adults consider underlying immunocompromised
What is staphylococcal scaled skin syndrome?
Staphylococcus aureus produces an exfoliative toxin that causes the outer layers of skin to blister and peel, as if they’ve been doused with a hot liquid
What does SSSS stand for?
Staphylococcal scaled skin syndrome
Who is commonly affected by staph scaled skin syndrome?
Children
Can occur in immunocompromised adults
What is the clinical presentation of staph scaled skin syndrome?
- Diffuse erythematous rash with skin tenderness
- More prominent in flexures
- Blistering and desquamation follows
- Staph procures toxin which targets desmoglein 1
- Fever and irritability
What is the treatment of staph scaled skin syndrome?
- Admission for IV antibiotics initially and supportive care
- Generally resolves over 5-7 days with treatment
What is urticaria?
Raised, itchy rash that appears on the skin
What is urticaria also known as?
Also known as hives, weals, welts or nettle rash
What is the clinicla presentation of urticaria?
- Central swelling of variable size, surrounded by erythema
- Dermal oedema
- Itching, sometimes burning
- Histamine release into dermis
- Fleeting nature, duration is 1 to 24 hours
- Angioedema
- Deeper swelling of the skin or mucous membranes
When does acute urticaria become chronic?
After 6 weeks of history
What are causes of acute urticaria?
- Idiopathic 50%
- Infection, usually viral 40%
- Drugs, IgE mediated 9%
- Food, IgE mediated 1%
What is the treatment of acute uticaria?
- Oral histamine
- Taken continuously
- Up to 4x dose
- Short course of oral steroid may be of benefit if clear cause and this is removed
- Avoid opiates and NSAIDs if possible (exacerbate urticarial)
What is the cause of chronic uticaria?
- Autoimmune/idiopathic 60%
- Physical 35%
- Vasculitic 5%
- Rarely a type 1 hypersensitivity reaction
What is the treatment of chronic uticaria?
- Omalizumab
- Monoclonal antibody to IgE
