Background: Sistemic Lupus Erytematosus (SLE) presents with a broad spectrum of dermatological manifestations. A rare but severe cutaneous presentation resembling Stevens-Johnson syndrome (SJS) or toxic epidermal necrolysis (TEN) has been reported. Its prevalence is very low, estimated al 0.07% in some series, making it a poorly documented entity. The presence of an SJS/TEN-like dermatosis in SLE correlates with high disease activity. Differentiating between true drug-induced SJS/TEN and lupus-associated dermatosis is crucial for appropriate treatment.

Case report: A 19-year-old female with a history of methamphetamine use but no reported medication intake presented with a progressive cutaneous eruption. One month before admission, she developed vesicular lesions on photo-exposed areas, evolving into crusted and desquamative plaques affecting the face, scalp, and arms. The condition was accompanied by fever (38ºC), asthenia, and headache, along with two syncopal episodes. Examination revealed erythematous-crusted lesions, papules, and erosions on the head, neck, and upper extremities, with necrotic crust around the perioral area but no oral mucosal involvement. A skin biopsy showed superficial leukocytoclastic vasculitis. Laboratory findings included normocytic anemia, thrombocytopenia, hypocomplementemia, proteinuria, and positive ANA, anti-dsDNA, anti-Smith, and anti-beta-2-glycoprotein antibodies. A renal biopsy confirmed lupus nephritis (class II mesangial proliferative). During hospitalization, she experienced a generalized tonic-clonic seizure, with MRI findings consistent with cerebral vasculitis and microinfarcts. SLE was diagnosed base on EULAR/ACR criteria with high disease activity (SLEDAI 34). She received methylprednisolone pulses and topical hydrocortisone, with complete resolution of skin lesions in two weeks.

Conclusion: In necrotic epidermal dermatoses with photodistribution and no clear triggers, SLE should be considered. Histological findings are essential to distinguish lupus-associated dermatosis from SJS/TEN. Severe skin involvement may indicate high SLE activity and warrants systemic evaluation to prevent complications.