FIXED DRUG ERUPTION SECONDARY TO FLUCONAZOLE CONFIRMED BY SELF-CHALLENGE

Abstract

<h3>Introduction</h3> Fixed drug eruption (FDE) can have a wide array of culprits, especially in patients who use multiple medications. We present a patient with Fixed Drug Eruption (FDE) secondary to fluconazole. <h3>Case Description</h3> A 36-year-old female was evaluated for recurrent pruritic and tender violaceous to hyperpigmented patches on her face (Figure 1A), neck, upper extremities, buttocks, flank, and genitals. Patches would blister after 2-3 days. These lesions occurred every 2-3 months for 1 year with Non-Steroidal Anti-inflammatory Drugs (NSAIDs) or fluconazole, and after her second Pfizer COVID-19 vaccine with acetaminophen as premedication. Punch biopsy showed focal dyskeratosis, papillary dermal eosinophils and neutrophils (Figure 1B). She was diagnosed with FDE and instructed to avoid NSAIDs, Polyethylene Glycol (PEG), over-the-counter medications, and fluconazole. Patch testing was performed for fluconazole (pet 5%), ibuprofen (pet 5%), celecoxib (pet 10%), povidone (pet 2% and liquid), and croscarmellose (pet 10% and liquid). All patch tests were negative at 48 hours, 72 hours, 5 days, and 7 days readings. Prior to performing a provocation test, the patient self-administered fluconazole for vaginal itching and the FDE recurred within 2 minutes on the same locations. She tolerated celecoxib and COVID19-vaccine booster without adverse reactions. The patient was instructed to avoid all azoles and use alternative agents. <h3>Discussion</h3> When multiple possible agents are suspected in FDE, patch testing followed by provocation tests may be considered. In this case, the diagnosis was confirmed by self-administration of fluconazole.