Pruritus and Tense Bullae After Discontinuation of Pembrolizumab in a Patient With Renal Cell Carcinoma

A 53-year-old woman developed widespread tense bullae with pruritus and oral mucosal lesions recalcitrant to corticosteroids during a treatment with pembrolizumab for stage IV renal cell carcinoma that persisted after discontinuation of the drug. ESR and CRP levels were elevated and biopsy suggested an autoimmune bullous process, but direct immunofluorescence results were negative. What is the diagnosis and what would you do next?
Source: JAMA - Journal of the American Medical Association - Category: General Medicine Source Type: research