Acute and Emergency Dermatology Flashcards
How to manage drug reactions including Stevens-Johnson syndrome/toxic epidermal necrolysis spectrum.
- Identify and stop culprit drug as soon as possible
- Supportive therapy
Consider;
- High dose steroids
- IV immunoglobulins
- Anti-TNF therapy
- Cyclosporin
How to manage erythroderma.
- Appropriate setting: ITU or burns unit
- Disease specific therapy; treat underlying cause e.g. drugs
- Careful fluid balance
- Good nutrition
- Temperature regulation
- Emollients
- Oral and eye care
- Anticipate and treat infection
- Manage itch
Describe erythroderma.
Any inflammatory skin disease affecting >90% of total skin surface.
List the causes of erythroderma.
- Psoriasis
- Eczema
- Cutaneous Lymphoma
- Drugs
- Hereditary disorders
- Idiopathic
Describe Stevens Johnson syndrome/toxic epidermal necrolysis.
- Severe drug reaction to e.g. antibiotics, anticonvulsants, NSAIDs
- Both thought to form part of same spectrum
- Rare
- Can be delayed onset
SJS = <10% epidermal detachment. Overlap = 10-30%. TEN = >30%.
Describe the clinical features of Steven Johnson syndrome.
- Fever, malaise, arthralgia
- Ulceration of mucous membranes
Rash;
- Maculopapular, target lesions, blisters
- Erosions covering <10% of skin surface
Mouth ulceration;
- Greyish white membrane
- Haemorrhagic crusting
Describe the clinical features of toxic epidermal necrolysis.
- Often presents with prodromal febrile illness
- Ulceration of mucous membranes
Rash;
- May start as macular, purpuric or blistering
- Rapidly becomes confluent
- Sloughing off of large areas of epidermis – ‘desquamation’
- Nikolsky’s sign may be positive
Describe the prognosis of Stevens Johnson syndrome/toxic epidermal necrolysis.
- Mortality: 10% in SJS, 30% in TEN
SCORTEN;
- Age >40
- Malignancy
- Heart rate >120
- Initial epidermal detachment >10%
- Serum urea >10
- Serum glucose >14
- Serum bicarbonate <20
Describe the long term complications of Stevens Johnson syndrome/toxic epidermal necrolysis.
- Pigmentary skin changes
- Scarring
- Eye disease and blindness
- Nail and hair loss
- Joint contractures
Describe erythema multiforme and its onset.
Hypersensitivity reaction usually triggered by infection;
- Most commonly HSV
- Then Mycoplasma pneumonia
Abrupt onset;
- 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 centre
- “Target” lesions
Describe the management of erythema multiforme.
- Self limiting and resolves over 2 weeks
- Symptomatic and treat underlying cause
Describe the onset, epidemiology and mortality of drug reaction with eosinophilia and systemic symptoms (DRESS).
- Onset 2-8 weeks after drug exposure
- Incidence estimated between 1 in 1000-10,000
- Mortality up to 10%
Describe the clinical features of drug reaction with eosinophilia and systemic symptoms (DRESS).
- Fever and widespread rash
- Eosinophilia and deranged liver function
- Lymphadenopathy
- +/- other organ involvement
Describe the management of drug reaction with eosinophilia and systemic symptoms (DRESS).
- Stop causative drug
- Symptomatic and supportive
- Systemic steroids
- +/- Immunosuppression or immunoglobulins
What is pemphigus?
A rare skin disorder where the immune system mistakes the skin and mucous membranes as foreign.
Describe the clinical features of pemphigus.
Skin;
- Flaccid blisters, rupture very easily
- Intact blisters may not be seen
- Common sites: face, axillae, groins
- Nikolsky’s sign may be positive
- Commonly affects mucous membranes
- Ill-defined erosions in mouth
- Can also affect eyes, nose and genitals
Define ‘pemphigoid’.
- Antibodies directed at dermo-epidermal junction
- Intact epidermis forms roof of blister
- Blisters are usually tense and intact
Pemphigus vs pemphigoid.
Pemphigus;
- Uncommon
- Middle aged patients
- Affects epidermis
- Blisters very fragile, may not be seen intact
- Patients may be very unwell
If extensive;
- Treat with systemic steroids - Dress erosions
- Supportive therapies
Pemphigoid;
- Common
- Elderly patients
- Affects derma-epidermal junction
- Blisters often intact and tense
- Even if extensive, patients are systemically well
- If localised, topics steroids
- If diffuse, systemic therapy
What are the common causes of (erythrodermic and pustular) psoriasis?
- Infection
- Sudden withdrawal of oral steroids or potent topical steroid
Describe the onset and clinical features of (erythrodermic and pustular) psoriasis.
- Rapid development of generalised erythema +/- clusters of pustules
- Fever, elevated WCC
Describe the management of (erythrodermic and pustular) psoriasis.
- Exclude underlying infection
- Bland emollient
- Avoid steroids
- Often require initiation of systemic therapy
What is eczema herpeticum?
Disseminate herpes virus infection on a background of poorly controlled eczema.
Describe the clinical features of eczema herpeticum.
- Monomorphic blisters and “punched out” erosions
- Generally painful, not itchy
- Fever and lethargy
Describe the management of eczema herpeticum.
- Aciclovir
- Mild topical steroid if required to treat eczema
- Treat secondary infection
- Ophthalmology input if peri-ocular disease
- In adults, consider underlying immunocompromise
