Impact of Poor Adherence to Treatment on Recurrent Disease Activity in Pemphigus Foliaceus: A Case Report

Pemphigus foliaceus is a rare autoimmune blistering disease characterized by superficial intraepidermal blister formation and chronic relapsing disease activity. Although systemic immunosuppressive therapy remains the cornerstone of treatment, adherence to both systemic and topical therapies may influence disease control, skin barrier integrity, and susceptibility to secondary infections. We present the case of a 73-year-old man with a history of hypertension, type 2 diabetes mellitus, and chronic ischemic heart disease who developed pemphigus foliaceus confirmed by clinical and histopathological findings. The disease initially manifested with vesicles and flaccid bullae involving the face and chest that progressed to erosions with serohematic crusts. The patient initially received systemic corticosteroids, antihistamines, and topical therapy without adequate response, requiring hospitalization and treatment with intravenous immunoglobulin. Therapy was later adjusted to include mycophenolic acid and corticosteroid tapering, achieving partial clinical improvement. During follow-up, the patient experienced multiple relapses associated with inconsistent adherence to topical therapy and unsupervised discontinuation of systemic corticosteroids. Despite reintroduction of immunosuppressive therapy, intermittent cutaneous activity persisted. On his final hospital admission, he developed secondary cutaneous and urinary infections caused by Klebsiella pneumoniae and Enterococcus faecalis, progressing to septic shock despite advanced medical management. This case highlights the challenges of treatment adherence in pemphigus foliaceus and emphasizes the multifactorial nature of severe disease progression in elderly patients with multiple comorbidities. Inadequate adherence, persistent disease activity, chronic immunosuppression, skin barrier dysfunction, and secondary infections may collectively contribute to unfavorable clinical outcomes. Reinforcement of patient education, close follow-up, and careful monitoring remain essential components in the management of autoimmune blistering diseases.