[4] Stevens-Johnson Syndrome Flashcards
What is Steven’s-Johnson Syndrome (SJS)?
An immune complex mediated hypersensitivity disorder
What does SJS form a spectrum with?
Toxic epidermal necrolysis (TEN)
Which is less severe, SJS or TEN?
SJS
When is the disease considered SJS not TEN?
Under 10% skin surface involvement
What is SJS/TEN in terms of skin involvement?
10-30%
How much skin is involved in TEN?
> 30%
What sort of hypersensitivity reaction is SJS?
Type 4
What happens in the type 4 hypersensitivity reaction of SJS?
A drug or its metabolite stimulate cytotoxic T cells and T helper cells to initiate autoimmune reactions that attack self-tissues
What percentage of SJS cases are caused by medication?
75%
What percentage of SJS cases are caused by infection and other causes?
25%
What are some examples of medications that can cause SJS?
- Allopurinol
- Carbamazepine
- Sulfonamides
- Antiviral agents such as nevirapine and abacavir
- Anticonvulsants
- NSAIDs
- Salicylates
- Sertraline
What types of infections can cause SJS?
- Viral
- Bacterial
- Fungal
- Protozoal
What viral infections can cause SJS?
- HSV
- EBV
- Enteroviruses
- Others
What bacteria can cause SJS?
- Group A β-haemolytic strep
- Diphtheria
- Mycobacteria
What protozoa can cause SJS?
- Malaria
- Trichominiasis
What other than infection and medications can cause SJS?
Immunisations
What immunisations can cause SJS?
- Measles
- Hep B
What are the risk factors for SJS?
- HIV/AIDS
- SLE
- Genetic factors
How does SJS often start its presentation?
With a non-specific URTI that can be associated with ;
- Fever
- Sore throats
- Headache
- Arthralgia
- Vomiting and diarrhoea
- Malaise
After URTI symptoms in early SJS, how does presentation progress?
To suddenly developing mucocutaneous lesions
How long do the outbreaks of mucocutaneous lesions in SJS typically last?
2-4 weeks
Are SJS lesions pruritic?
Not generally
How do the mucocutaneous lesions of SJS present in the mouth?
As severe oromucosal ulceration
How can respiratory involvement present in SJS?
As a cough productive of thick, purulent sputum
What symptoms may present if there is genitourinary involvement in SJS?
Dysuria or inability to pass urine
What symptoms may present if there is ocular involvement in SJS?
- Painful red eye
- Purulent conjunctivitis
- Photophobia
- Blepharitis
How is SJS diagnosed?
On the basis of clinical classification and histopathology of skin biopsy
What will histopathology show in SJS?
The bullae are subepidermal and there may be epidermal cell necrolysis
What investigations are important in SJS to assess severity and level of dehydration?
- Electrolytes
- Glucose
- Bicarbonate
What are the differentials for SJS?
- Bullous pemphygoid
- Chemical or thermal burns
- Erythroderma
- Exfoliative dermatitis
- Maculopapular drug rashes
- Staphylococcal scalded skin syndrome
Is SJS worrying?
Yes, its a dermatological emergency 🚨
When managing SJS what should be done if possible?
Identify the causative agent and withdraw immediately
What system can be used to rapidly assess prognosis of SJS?
SCORTEN system
What score on the SCORTEN system for assessing SJS indicates need for ITU treatment?
3 or more
What are the skin lesions in SJS managed the same as?
Burns
What supportive therapy is used in treating SJS?
- Maintain airway
- Maintain haemodynamic stability
- Correct fluid and electrolyte loss IV
- Pain relief
What can occur at lesion sites in SJS?
Secondary infection
How can oral lesions be managed in SJS?
Mouthwashes of topical anaesthetics to reduce pain and allow fluid intake
How should ocular SJS be managed?
Frequent ophthalmology assessment and frequent eye drops including antibiotics and steroids where required
What are the potential complications of SJS?
- Dehydration
- Malnutrition
- Shock and multi-organ failure
- Thromboembolism and DIC
- Secondary infection
- Scarring
- GI complications
- Eye complications
- Mucosal shedding of airways leading to respiratory failure
What are the potential GI complications of SJS?
- Ulceration
- Necrolysis
- Strictures
- Perforation
What are the potential eye complications of SJS?
- Corneal ulceration
- Anterior uveitis
- Sight impairment
What are the long term skin sequelae that some survivors of SJS experience?
- Hyperhidrosis
- Hair loss
- Heat and cold sensitivity
- Scarring
- Irregular pigmentation
What are the long term mucous membrane sequelae that som survivors of SJS experience?
Vaginal, urethral and anal strictures
What are the ocular sequelae that some survivors of SJS experience?
- Photophobia
- Sight impairment
