Dermatology - Dermatological Emergencies Flashcards
Name some dermatological emergencies
- Erythroderma
- Steven Johnsons Syndrome
- Toxic Epidermal Necrolysis
- Erythema mulitforme
- Eczema herpeticum
What is erythroderma?
Widespread erythema (reddening of skin) covering at least 90% of the skin surface.
Why is erythroderma an emergency?
Widespread erythroderma can lead to heat and fluid loss, causing hypothermia and systemic symptoms.
What is erythroderma usually 2ary to?
Inflammatory skin disease:
- Dermatitis/eczema – atopic, seborrhoeic, contact
- Psoriasis – most common precipitant
- Pityriasis rubra pilaris
What condition is the most common precipitant to erythroderma?
Psoriasis
Give some other causes of erythroderma
- Drug allergies (penicillin, allopurinol, sulphonamides)
- Systemic malignancy
- HIV
- Idiopathic
- Sezary syndrome – a form of cutaneous T-cell lymphoma which causes erythroderma, lymphadenopathy and hepatosplenomegaly that is characterised by Sezary cells (atypical T cells) in the peripheral circulation
What typical symptoms are seen in erythroderma?
- Red, painful, itchy skin over a large area
- Malaise
What typical signs are seen upon clinical examination in erythroderma?
- Hot, erythematous skin covering at least 90% of the skin surface
- Also known as ‘red man syndrome’
- Generalised lymphadenopathy
- Inflamed, oedematous, scaly skin
- Exfoliative dermatitis – ‘skin peeling off’
Management of erythroderma?
Hospital admission with close monitoring of electrolytes and fluid balance - those who are systemically unwell require admission to specialist burns unit or ICU
- Emollients
- Wet wraps
- Topical steroids
Give some complications of erythroderma
- 2ary bacterial infection
- Fluid & electrolyte imbalance
- Hypothermia 2ary to impaired thermoregulation
- Cardiac failure or shock
- Capillary leak syndrome
- Mortality up to 40%
What is Steven Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN)?
SJS and TEN are variants of the same condition. They are severe mucocutaneous reactions, almost always secondary to medications.
Immune complex mediated hypersensitivity disorder syndromes that can range from mild to severe. It forms a spectrum with TEN at the most severe end of the spectrum.
They are dermatological emergencies!
What are SJS/TEN almost always 2ary to?
Medications
What medications are typically responsible for SJS/TEN?
- Allopurinol
- Anti-epileptic drugs
- Sulfonamides
- Antivirals
- NSAIDs
- Salicylates
- Sertraline
- Imidazole
- Beta lactams (penicillins & cephalosporins)
SJS/TEN can also occur 2ary to infections. Give some examples of infections
- Viral (common): herpes simplex virus, Epstein Barr virus, HIV, influenza, hepatitis
- Bacterial & fungal (less common)
SJS and TEN can be stratified based on % body surface area of detached epidermis.
Define each
- SJS → <10% of body surface area
- SJS/TEN → 10-30% of skin
- TEN → >30% of skin involvement
What investigation is required to diagnose SJS/TEN?
Skin biopsy
How does SJS/TEN initially present?
Prodromal flu-like/non-specific URT illness e.g. sore throat, fever, cough – usually presents within a week of taking a drug
What should you ensure to ask the patient about in SJS/TEN?
Ask about DH (any new drugs?) and PMH
Describe the rash in SJS/TEN
- Painful rash starting on the trunk which then spreads over several hours/days onto the face and limbs
- Rash initially starts are macules (target shaped) and progresses to blisters and eventually desquamation
What is Nikolsky’s sign?
gentle rubbing of skin causes desquamation
Is Nikolksy’s sign positive in SJS/TEN?
Yes
As well as the skin, extensive mucocutaneous necrosis/ulceration affects at least 2 other regions in SJS/TEN. Name some regions
- Conjunctiva (conjunctivitis)
- Cornea (ulceration)
- Mouth – ask about mucosal membrane involvement (or look)
- Urethra
- Pharynx
- GI tract
In young children, what is a major differential for SJS/TEN?
staphylococcal scalded skin syndrome (SSSS)
SSSS vs SJS/TEN?
SJS/TEN involves necrosis of the full epidermal layer, SSSS is intraepidermal
Management of SJS/TEN?
- Supportive care:
- Stop taking causative drug
- Nutritional care
- Antiseptics
- Analgesia
- Ophthalmology referral
- Steroids
- Immunoglobulins
- Immunosuppressants
Complications of SJS/TEN?
- Dehydration/hypovolaemic shock
- 2ary infection of skin or mucous membranes
- Sepsis
- Disseminated intravascular coagulation
- Thromboembolism
- Death:
- SJS 10% mortality rate
- TEN 30% mortality rate
Mortality rate of SJS?
10%
Mortality rate of TEN?
30%
What is eczema herpeticum?
A complication of atopic eczema that occurs with infection of the herpes simplex virus (HSV).
What is eczema herpeticum thought to be due to?
Thought to be due to a reduced level of immunity to HSV in patients with atopic dermatitis.
Who does eczema herpeticum commonly affect?
- Can affect any age but commonly affects infants and children
- More common in those with severe atopic dermatitis/eczema
When do symptoms of eczema herpeticum tend to develop following contact with HSV?
5-12 days
Symptoms seen in eczema herpeticum?
- General malaise
- Fever
- New, itchy, painful lesions
- Gritty or sore eyes (if eye involvement present)
Describe the skin lesions seen in eczema herpeticum
- Groups of itchy painfulblisters, erosions, and crusted papules
- May be evidence of 2ary bacterial infection (e.g. cellulitis, impetigo)
Is there lymphadenopathy in eczema herpeticum?
Yes - Local lymphadenopathy near the site of the lesions
What can eczema herpeticum be mistaken for?
Impetigo
Viral and bacterial swabs can be taken from the base of a new blister in eczema herpeticum. What may each reveal?
Viral swabs → presence of HSV type 1 or 2 would confirm diagnosis
Bacterial swabs → may reveal 2ary infection with staphylococci or streptococci
Pharmacological management of eczema herpeticum?
- Antivirals (e.g. aciclovir) – IV can be used in severe cases
- Abx treatment if 2ary bacterial infection present
Complications of eczema herpeticum?
- Herpes hepatitis
- Encephalitis
- Disseminated intravascular coagulation
- Death (very rare)
