StevensJohnson

Stevens-Johnson syndrome, often abbreviated as SJS, is a rare but potentially life-threatening mucocutaneous reaction. It typically begins with fever, malaise, and flu-like symptoms, followed by painful mucosal erosions and a rapidly spreading rash. Involvement of the skin and at least one mucous membrane is characteristic, with varying degrees of epidermal detachment. When detachment covers less than 10% of the body surface area it is classified as Stevens-Johnson syndrome; 10% to less than 30% as SJS/TEN overlap; and 30% or more as toxic epidermal necrolysis (TEN). The disease is a medical emergency requiring prompt evaluation and management.

Causes and risk factors are most commonly medications, including sulfonamides, anticonvulsants (such as carbamazepine, lamotrigine, and phenobarbital), allopurinol, and some nonsteroidal anti-inflammatory drugs. Infections, particularly Mycoplasma pneumoniae, can also trigger SJS. Genetic predisposition, notably certain HLA alleles in specific populations, increases risk for drug-induced SJS. The syndrome can affect all ages but has notable incidence in young adults and children; early identification and withdrawal of the offending agent are critical.

Diagnosis relies on clinical presentation supported by histopathology. A skin biopsy typically shows full-thickness epidermal necrosis with a subepidermal split. Immunofluorescence helps distinguish it from other blistering diseases. Management emphasizes immediate removal of the offending drug, intensive supportive care (often in a burn unit or intensive care setting), wound care, fluid and electrolyte management, nutrition, and prevention of infections. Multidisciplinary care is common, with attention to ocular, oral, and genital tract involvement.

Prognosis varies; mortality historically ranges from about 5% for SJS to higher rates for TEN. The SCORTEN index is used to estimate risk. Stevens-Johnson syndrome remains a medical emergency due to its rapid progression and potential for severe complications.