Acute and emergency dermatology Flashcards
What are the functions of the skin?
Mechanical barrier to infection Temperature regulation Fluid and electrolyte balance Vit D synthesis Sensation
What are the consequences of skin failure?
Sepsis Hypo and hyperthermia Protein and fluid loss Renal impairment Peipheral vasodilation
What is erythroderma?
Widespread skin disease affecting >90% total skin surface
What can cause erythroderma?
Psoriasis Eczema Drugs Cutaneous lymphoma Hereditary disorders
How often to drug reactions happen?
2-3% patients
What is a kind form of drug reaction?
Morbilliform exanthema
What are severe forms of drug reaction?
Erythroderma
Stevens Johnson syndrome/toxic epidermal necrolysis
DRESS
What causes SJS and TEN?
Drugs- antibiotics, anticonvulsants, allopurinol, NSAIDs
What are the clinical features of SJS?
Fever, malaise, arthralgia
Rash
Mouth ulceration
Ulceration of other mucous membranes
Describe the SJS rash
Maculopapular, taget lesions, blisters
Erosions covering <10% skin’s surface
Describe the mouth ulceration in SJS
Greyish white haemorrhage and haemorrhage crusting
What is the presentation of TEN?
Prodromal febrile illness
Ulceration of mucous membrane
Rash
Describe the TEN rash
May start as macular, purpuric or blistering
Rapidly becomes confluent
“Sloughing off” of large areas of epidermis
Nikolsky’s sign may be +
What is the management of SJS and TEN?
Identify and stop culprit drug
Supportive care- high dose steroids, IV immunoglobulins
Anti TNF therapy
Ciclosporin
What is the prognosis for SJS?
10% mortality
What is the prognosis for TEN?
30% mortality
What are the possible long term complications of SJS and TEN?
Pigmentary skin changes Scarring Eye disease and blindness Nail and hair loss Joimt contractures
What is DRESS?
Drug reaction with eosinophilia and systemic symptoms
When is the onset of DRESS?
2-8 weeks after drug exposure
What are the signs and symptoms of DRESS?
Fever and widespread rash
Eosinophilia and deranged liver function
Lymphadenopathy
May or may not have other organ involvement
Wat is the management of DRESS?
Stop causative drug
Symptomatic ans supportive- systemic steroids +/- immunosuppression or immunoglobulins
What is erythema multiforme?
Hypersensitivity reaction usually triggered by infection causing abrupt onset of 100s of lesions over 24 hours
What is the most common trigger of erythema multiforme?
HSV
Describe the lesions in erythema multiforme
Distal and spread proximally
Palms and soles and mucosal surfaces most affected
Evolve over 72 hours- Pink macule become elevated and blister in the centre, target lesions
What is the treatment of erythema multiforme?
Treat symptoms and underlying cause but self limiting
How quickly does erythema multiforme resole?
2 weeks
What is pemphigus?
Autoimmune condition with antibodies targeted at desmosomes
What are the clinical features of pemphigus?
Flacid blisters that rupture easily
Nikolsky’s sign may be +
Ill defined erosions in mouth
Very unwell in extensive disease
What sites are commonly affected by pemphigus?
Face
Axillae
Groin
Mucous membranes- mouth, eyes, nose, genitals
What is the treatment of pemphigus?
Systemic steroids
Dress erosions
Supportive therapy
What is pemphigoid?
Autoimmune condition causes by antibodies directed at demo-epidermal junction
What is the presentation of pemphigoid?
Tense and intact blisters with roof formed by epidermis
Fairly systemically well
Common in older patients
What is the treatment of pemphigoid?
Steroids- topical if localised, systemic if diffuse
What are erythrodermic psoriasis and pustular psoriasis?
Psoriasis caused by infection or sudden steroid withdrawal
What are the clinical features of erythrodermic and pustular psoriasis?
Rapid development od generalised erythema, with or without clusters of pustules
Fever, elevated WCC
What is the treatment of erythrodermic and pustular psoriasis?
Bland emollient
Avoid steroids
Systemic therapy if severe
What is eczema herpeticum?
Disseminated herpes virus infection on background of poorly controlled eczema
What are the clinical features of eczema herpeticum?
Monomorphic blisters and punched out erosions- painful but not itchy
Fever and lethargy
What is the treatment of eczema herpeticum?
Aciclovir
Mild topical steroid to treat eczema
Treat secondary ifection
Who is staphylococcal scalded skin syndrome seen in?
Mainly children, some immunocompromised adults
What are the clinical features of staphylococcal scalded skin syndrome?
Diffuse erythematous rash with skin tenderness
More prominent in flexures
Blistering and desquamation (skin peeling) follows
Fever and irritability
What is the treatment of staphylococcal scaled skin syndrome?
IV antibiotics and supportive care
What are the clinical features of urticaria?
Central swelling of variable size, surrounded by erythema
Dermal oedema
Itching, sometimes burning
Fleeting nature- 1-24 hours
What are the 2 types of urticaria?
Acute
Chronic
What is acute urticaria?
<6 week history
Wat causes acute urticaria?
Idiopathic
Infection
Drugs- IgE mediated
Food- IgE mediated
What is the treatment of acute urticaria?
Oral antihistamine
Short course of oral steroids
Avoid opiates and NSAIDs
What causes chronic urticaria?
Autoimmune/idiopathic
Physical
VAsculitis
What is the treatment of chronic urticaria?
Omalizumal- monoclonal antibody to IgE
