Sporadic Pemphigus Foliaceus in a 75-year-old Filipino female: A Case Report
Pemphigus Foliaceus (PF) is an uncommon autoimmune blistering disease with male predominance in Japanese literature,
and onset within the 4th – 6th decades of life. We report a case of an elderly Filipino woman who presented with a one-year history of crusted erosions on the face, trunk, and extremities. Most lesions began as erythematous patches and plaques that would progress into flaccid bullae and woud easily erode. She was only maintained on irbesartan, atorvastatin, and multivitamins daily. There was no known familial history of blistering diseases. Skin punch biopsy revealed a vacuolar interface dermatitis and direct immunofluorescence showed granular intercellular staining of IgG and C3, anti-nuclear antibody stanining of IgG, and granular vascular staining of fibrinogen, consistent with Pemphigus group. Anti-nuclear antibody level was negative and serum ELISA levels showed positivity to only Desmoglein 1, and negative for Desmoglein 3- thus, clinching the diagnosis of PF. She was started on oral prednisone therapy at 0.75mg/kg/day and azathioprine 50mg/day, along with ranitidine, loratadine, diphenhydramine, calcium + vitamin D3 supplements, and a topical compounding of clobetasol propionate cream, fusidic acid cream, and a bland emollient. Clinical improvement was observed at one month of treatment where most lesions became darkly erythematous to hyperpigmenting thin plaques and no recurrence of erosions. Prednisone dosage was then slowly tapered to 5mg/day of prednisone at 4 months of treatment. No untoward events developed during the course of therapy except for one episode of upper respiratory tract infection which resolved after one week of Cefixime. Only 100 cases of PF were reported in the Philippine Dermatological Society Health Information System from 2011 to 2018 with female to male ratio of 2:3. This report aims to elucidate the importance of prompt recognition and treatment of this condition to achieve good prognosis and low morbidity.