Acute and Emergency Dermatology Flashcards
Describe the morbilliform rash
- Similar to a measles like rash
- Erythematous
- Blanching
- Truncal/widespread
Describe urticaria
- Red itchy hives
- Looks a bit like a nettle rash
- Angiooedema when mucosal surfaces are involved (swollen lips, eyes)
Describe a phototoxic rash
- Patches of erythema -> widespread erythema
* Occurs in areas exposed to UV
Describe a pustular drug rash
Monomorphic pustules which look a bit like spots
Describe lichenoid rash
- Purple/brown spots with a. white lacy network
* looks similar to the rash lichen planus (which is normally red)
Describe vasculitis
- Inflammation of the blood vessels making them leaky
- Can be blisters and ulceration
- Often localised and not rapidly progressive (also not commonly systemically unwell)
What are the triggers of vasculitis?
- Drugs
* Connective tissue disease e.g. Rheumatoid arthritis
If someone presents with vasculitis what should you check for?
Systemic vasculitis i.e. renal BP, urinalysis, any neurological features?
Describe drug induced psoriasiform rash
- Psoriasis like rash
- Well demarcated pink erythema with scale
- Sudden onset, no family history
Name two drug/infection induced blistering disorders
- Steven Johnson Syndrome
* Toxic epidermal necrolysis
Name two immunobullous diseases causing blistering disorders
- Bullous pemphigoid
* Bullous pemphigus
What is Steven Johnson Syndrome on a spectrum with?
Toxic epidermal necrolysis
Describe toxic epidermal necrolysis
- Dermatolgocial emergency
- Majority is drug induced
- most severe is when the mucous membranes are involved
- Stop using the suspected drug immediately
What is the management fo toxic epidermal necrolysis?
- In patient term/ITU/burns
- analgesia (full thickness to nerve endings so very very painful)
- Fluid balance: SCORTEN severity scale
- Special sheets/mattress/non adherent dressing
- Infection control and infection prophylaxis
- Input from urology/gynae/opthalmology
Describe staphylococcal scalded skin syndrome
- blistering skin condition
* Caused by the toxin of the staph bacteria (need to clear bacterial infection to treat)
What is erythema multiforme?
- Self limiting allergic reaction
- HSV/EBV/occasionally drug cause
- Taget lesions (rings with circle in centre)
What happens in the immunobullous disorders?
Autoantibodies to various skin component i.e. basement membrane proteins in BP on skin biopsy
name 5 immunobullous disorders
- Bullous pemphigoid
- Mucous membrane pemphigoid
- Paraneoplastic pemphigoid
- Pemphigus
- Dermatitis herpetiformis (coeliac disease)
What is the difference between bullous pemphigoid and pemphigus vulgarisms on immunofluorescene of the skin?
- Bullous pemphigoid: split is between the epidermis and the dermis
- Pemphigus vulgaris: split is more superficial
What is the appearance of bullous pemphigoid?
Intact blisters
Describe the appearance of pemphigus
- Red blotches, some deeper skin lesions
* Sheared layers have come off, no intact blisters
Describe the appearance of dermatitis herpetoformis
Tiny vesicle blisters, normally symmetrical and on the extensors of elbow, buttocks or knees
What investigtations should be carried out in immunobullous disorders?
Skin biopsy with immunofluorescence
What is the treatment of immunobullous disorders?
- Reduce autoimmune reaction (topical/oral corticosteroids)
- Steroid sparing agents (aziothioprine)
- Burst any blisters
- Dressings and infection control
- Check for oral/mucosal involvement
- Consider a screen for underlying malignancy
