Acute and Emergency Dermatology Flashcards
What are the different types of skin drug reactions?
- Maculopapular,
- Urticaria,
- Morbilliform (blanching, erythematous rash)
- Papulosquamous,
- Photo-toxic,
- Pustular,
- Lichenoid rash (looks similar to lichen planus),
- Psoriasiform rash (sudden onset, common drugs include lithium and beta blockers)
What are some common drugs which can cause acute drug reactions?
- Antibiotics eg, penecillin and trimethoprim,
- NSAIDs,
- Chemotherapeutic agents,
- Psychotropic (chlorpromazine),
- Anti-epileptic,
- Cardiac drugs
What is the following rash and causes?
Vasculitis. Triggers include infection, drugs, connective tissue disease.
Looks similar to meningococcal rash but patient will be less unwell
What is a fixed drug rash?
It is a reaction which occurs in the same place everytime you take the same drug
What are some blistering disorders induced by drugs?
Steven Jonson syndrome (blistering and bleeding around mucous membranes) and toxic epidermal necrolysis
What are some immunobullous diseases?
- Bullous pemphigoid
- Bullous pemphigus
- Dermatitis herpetiformis (coeliacs disease)
What does the following image show? and describe the features
Toxic epidermal necrolysis. It is a dermatological emergency often induced by drugs which affects the mucous membranes. Need to stop precipitating drug and manage in patient with analgesia and fluid balance. Need strict infection control
Describe features of staphylococcal scalded skin syndrome?
It is a blistering condition characterised by detachment of the epidermis. It is caused by exotoxins released by staphylococcus
What is Erythema Multiforme
A self limiting allergic reaction. It can be caused by some viral infections or drugs. Appears with target/dart board lesions.
What is the difference between bullous pemphigoid and pemphigus vulgaris
Bullous pemphigoiD - Deep. Split is between dermis and epidermis.
PemphiguS vulgaris - Superficial split.
They both have autoantibodies to various proteins in the skin.
What is the investigations for immunobullous disorders?
Skin biopsy with immunofluoresence
What is the treatment of immunobullous disorders?
- Reduced the autoimmune reaction with steroids.
- Steroid sparing agents,
- Burt any blisters,
- Dressings and infection control,
- Check for mucosal involvement,
- For dermatitis herpetiformis then ensure gluten free diet and give oral dapsone.
What does the following image show?
Urticaria. A single lesion will come and go within 24 hours. May have some angioedema (not anaphylaxis). Acute is less than 6 weeks. Chronis is more than 6 weeks.
What are the different types of urticaria?
Immune mediated - Type 1 IgE response.
Non-immune mediated - diresct mast cell degranulation which can be caused by opiates, abx, contrast media or NSAIDs.
Treatment is via antihistamines, steroids, phototherapy, immunosuppression or omalizumab
What are some causes of acute urticaria?
Many are unknown but can be caused by:
- Viral infections,
- Medications,
- Food and food additives,
- Parasitic infections,
- Physical stimulants (cold, chlorine)
