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)
What is Eczema Herpeticum?
Disseminated Herpes Virus infection on a background of poorly controlled Eczema
What are the clinical features of Eczema Herpeticum?
- Monomorphic blisters and “punched out” erosions (quite a lot if them!)
- > generally painful, not itchy
- Fever and Lethargy
What is the management of Eczema Herpeticum?
- Aciclovir
- Mild topical steroid (for eczema)
- Treat secondary infection
- Ophthalmology input if peri-ocular disease
- In adults: consider underlying immunocompromisation
What is the pathophysiology of Saphylococcal Scalded Skin syndrome?
- Initial Staph. infection
- Produces a toxin which targets Desmoglein 1 (causes the cells to peel apart)
What are the clinical features of Staphylococcal Scalded Skin syndrome?
- Common in children, can also occur in immunocompromised adults
- Diffuse erythematous rash with skin tenderness
- More prominent in flexures
- Blistering and desquamation follows
- Fever and irritability
What is the management of Staphylococcal Scalded Skin syndrome?
- Requires admission for IV abx initially and supportive care
- Generally resolves over 5-7 days with treatment
What are the clinical features of Urticaria?
- Weal, Wheal or Hive:
- > central swelling of variable size, surrounded by erythema - dermal oedema
- > itching, sometimes burning (histamine release into dermis)
- > fleeting nature, duration: 1-24hrs
- Angioedema:
- > deeper swelling of the skin or mucous membranes
What causes Acute Urticaria?
- <6 week history*
- Idiopathic (majority)
- Infection (viral)
- Drugs (IgE mediated)
- Food (IgE mediated)
What is the treatment of Acute Urticaria?
- <6 week history*
- oral anti-histamine
- if severe: oral steroids
- avoid opiates and NSAIDs if possible (exacerbate urticaria)
What causes Chronic Urticaria?
- > 6 week history*
- Autoimmune/Idiopathic (majority)
- Physical
- > (ie. cold (ice cube on skin), friction, heat, drawing on yourself)
- Vasculitic
- Rarely Type 1 HS reaction!!*
What is first-line treatment for Acute Urticaria?
- > 6 week history*
- oral anti-histamine
- no place for oral steroids*
