Toxic epidermal necrosis-like acute cutaneous lupus erythematosus

A woman aged 69 years was diagnosed with cutaneous lupus erythematosus, exhibiting erythema on sun-exposed areas of her arms, with typical pathological findings, including lesional deposition of IgM and complement at the dermal–epidermal junction, revealed by direct immunofluorescence staining. We treated the erythema with topical glucocorticoids. At the time, the patient had no other symptoms. Although anti-Ro antibody was positive, anti-nuclear, anti-double stranded DNA antibodies, and rheumatoid factor were negative, and complement concentrations were normal. After one month, new erythematous lesions appeared on the woman's ears, face, and back, with rapidly progressing epidermal exfoliation and a toxic epidermal necrosis-like appearance (figure 1A and B). The patient was febrile (38°C) but did not have arthritis, mucosal ulceration, a history of new or altered medication, or acute sun exposure. Anti-nuclear antibody titres seroconverted to 1:80 with homogeneous fluorescence (normal dilution <1:40), and anti-double stranded DNA antibody concentration was elevated to 41·7 units per mL (normal range ≤12 units per mL). Additional blood tests showed a decrease in complement concentration, and a urine dipstick test was positive for protein. A skin biopsy from the woman's trunk revealed findings of full-thickness epidermal necrosis and separation of the epidermis consistent with toxic epidermal necrosis, and direct immunofluorescence staining at the perilesional area confirmed the diagnosis of cutaneous lupus (figure 1D–F). Based on the 2019 European League Against Rheumatism–American College of Rheumatology classification criteria, we diagnosed the patient with systemic lupus erythematosus with toxic epidermal necrosis-like acute cutaneous lupus erythematosus. We initiated high-dose prednisolone (1 mg/kg; 50 mg/day) and hydroxychloroquine (200 mg/day), and her symptoms and laboratory test abnormalities all improved (figure 1C).