Stevens–Johnson syndrome / toxic epidermal necrolysis
Also called SJS, TEN, SJS/TEN overlap, SJS/TEN spectrum
A drug-triggered T-cell attack on keratinocytes: fever and mucositis, then dusky targetoid macules that blister and shear off in sheets. One spectrum, staged by detached body surface area, under 10% SJS, over 30% TEN.
How it looks
Widespread dusky erythematous macules with targetoid centres coalescing over the trunk, flaccid bullae shearing with lateral pressure, and haemorrhagic crusting of the lips with oral and ocular erosions.
Rose is the lesion, grey the pattern the lesions make, green where on the body it lives.
Across skin tones
Duskiness, the grey-violet colour of dying epidermis, can be subtler against deeply pigmented skin; skin pain, mucositis, and Nikolsky sign do not depend on colour.
Don't miss
Any drug rash with skin pain, blisters, or mucosal involvement is SJS/TEN until proven otherwise. Hours matter.
Symptoms & course
- Skin PAIN, the most discriminating early symptom
- Fever and flu-like prodrome
- Painful mouth, eyes, and genital mucosa
Diagnostic approach
- Clinical recognition first; biopsy (full-thickness epidermal necrosis) confirms
- Identify the culprit drug, commonly allopurinol, aromatic anticonvulsants, sulfonamides, nevirapine, oxicams, started 1–3 weeks prior
Differential, and how to separate them
- Morbilliform drug eruption
Favours it: Itchy, painless, no mucositis or blistering
Against it: Pain, duskiness, mucosae, and epidermal detachment define SJS/TEN
- Pemphigus vulgaris
Favours it: Chronic course, anti-desmoglein antibodies
Against it: SJS/TEN is abrupt, febrile, and drug-timed
Management principles
- STOP the culprit immediately, the single most outcome-changing act
- Burn-unit level supportive care: fluids, temperature, wounds, nutrition
- Urgent ophthalmology, ocular scarring is the great cause of lasting morbidity
Clinical pearl: 'Does your skin hurt?' is the highest-yield question in all of drug-rash medicine.
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