Acute and Emergency Dermatology Flashcards
What is Erythroderma?
- A descriptive term rather than a diagnosis
- “Any inflammatory skin disease affecting >90% of total skin surface”
What are the different causes of Erythroderma?
- Psoriasis
- Eczema
- Drugs
- Cutaneous Lymphoma
- Hereditary disorders
- Unknown
What are the principles of management of Erythroderma?
- Appropriate setting: ?ITU or Burns unit
- Remove any offending drugs
- Careful fluid balance
- Good nutrition
- Temperature regulation
- Emollients (50:50 liquid paraffin:white soft paraffin)
- Oral and eye care
- Anticipate and treat infection
- > low-threshold for treatment of infection
- Manage itch
- Disease-specific therapy
- > treat underlying cause
What are the different clinical presentations of drug reactions?
Mild:
- Morbilliform Exanthem
Severe:
- Erythroderma
- Stevens-Johnson Syndrome (SJS)/Toxic Epidermal Necrolysis (TEN)
- Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS)
Which drugs are most likely to cause drug reactions?
- Abx.
- Anti-convulsants (aka. anti-epileptics)
- Allopurinol
- NSAIDs
What are the clinical features of SJS?
- Fever, malaise, arthralgia
- Rash:
- > maculopapular, target lesions, blisters
- > erosions covering <10% of skin surface
- Mouth ulceration:
- > greyish-white membrane
- > haemorrhagic crusting
- Ulceration of other mucous membranes
- > (ie. eyes, nose, genitals)
What are the clinical features of TEN?
- Often presents with prodromal febrile illness
- Ulceration of mucous membranes
- Rash:
- > macular, purpuric, blistering
- > rapidly becomes confluent
- > sloughing off large areas of epidermis: “desquamation” >30% BSA
- > Nikolsky’s sign +ve
What is the management of SJS and TEN?
- Identify and stop culprit drug ASAP
- Supportive Therapy
?possible ITU for TEN-end of the spectrum
What is SCORTEN?
- Predictor of mortality for pts presenting with TEN
- > 0-1 = >3.2%
- > 5 or more = >90% mortality
What are the long-term complications of SJS and TEN?
- Pigmentary skin changes
- Scarring
- Eye disease and blindness
- Nail and hair loss
- Joint contractures
What is Erythema Multiforme?
- HS reaction usually triggered by infection
- Most commonly HSV
What are the clinical features of Erythema Multiforme?
- Abrupt onset of up to 100s of lesions over 24hrs
- Palms and soles
- Mucosal surfaces
Evolve over 72hrs:
- > Pink macules, become elevated and may blister in the centre
- > “Target” lesions
What are the clinical features of DRESS?
- Onset 2-8 weeks after drug exposure
- Fever and widespread rash
- Eosinophilia and deranged liver function
- Lymphadenopathy
- +/- other organ involvement
What is the management of DRESS?
- Stop causative drug
- Symptomatic and supportive
- Systemic steroids
- +/- immunosuppression or immunoglobulins
What is the pathophysiology of Pemphigoid?
- Abs directed at dermo-epidermal junction (DEEP)
- Intact epidermis forms the roof of the blister
- Blisters are usually tense and intact (bullae, vesicles)
What is the pathophysiology of Pemphigus?
- Antibodies targeted at desmosomes (erosions)
SUPERFICIAL
What are the clinical features of Pemphigus?
- Uncommon
- Middle-aged pts
- V fragile blisters - may not be seen intact
- usually affects mucous membranes
- Pts may be v unwell if extensive
How is diagnosis of Pemphigus + Pemphigoid made?
Immunofluorescence biopsy
What is the treatment of Pemphigus?
- Systemic steroids
- Dress erosions
- Supportive therapies
What are the clinical features of Pemphigoid?
- Common
- Elderly pts.
- Blisters often intact, tense
- Even if extensive, pts are fairly well systemically
What is the treatment of Pemphigoid?
- Topical steroids (if localised)
- Systemic steroids (if diffuse)
What are the causes of Erythrodermic and Pustular Psoriasis?
- Can occur w/o a prev. history of Psoriasis
- Infection
- Sudden withdrawal or oral or potent topical steroids
What are the clinical features of Erythrodermic and Pustular Psoriasis?
- Rapid development of generalised Erythema, +/- clusters of pustules
- Fever, elevated WCC
What is the treatment of Erythrodermic and Pustular Psoriasis?
- Exclude underlying infection, bland emollient, avoid steroids
- Often requires initiation of systemic therapy
- > (psoriasis therapy ie. immunosuppressant, sometimes biologic therapy)
