Case Report: Dupilumab as a corticosteroid-sparing adjunct in severe mucocutaneous pemphigus vulgaris with prior avascular necrosis and chronic kidney disease.

Pemphigus vulgaris is a potentially life-threatening autoimmune blistering disease for which corticosteroid minimization can be difficult when prior steroid toxicity has already occurred. We report a 60-year-old woman with severe mucocutaneous pemphigus vulgaris confirmed by clinical, immunopathologic, and serologic findings, who had previously developed femoral head avascular necrosis during high-dose prednisone therapy and also had advanced chronic kidney disease, hypoalbuminemia, and anemia. Rituximab was discussed as a guideline-supported first-line option; however, after counseling regarding its expected benefits and potential adverse effects, the patient declined rituximab. Therefore, dupilumab was introduced off-label as an adjunctive corticosteroid-minimizing approach together with oral prednisone 30 mg/day and supportive care. The Pemphigus Disease Area Index was 111 during the first treatment week and decreased to 22 by week 6, when disease control was achieved with cessation of new lesions and marked healing of pre-existing erosions. Prednisone was then tapered gradually. Complete re-epithelialization was achieved by approximately month 4 while the patient was receiving oral prednisone 7.5 mg/day, and clinical stability was maintained through month 6 after dupilumab discontinuation at month 4. No adverse events were observed. This case supports the clinical feasibility of dupilumab-assisted corticosteroid minimization in selected patients with pemphigus vulgaris and major treatment-related constraints, while further evidence is needed regarding patient selection, duration of therapy, and long-term relapse risk.