(465) Fixed Drug Eruption, A Diagnosis to Keep in Mind

Track
Case Reports
Abstract

Fixed drug eruption (FDE) is a common recurrent cutaneous disorder presenting as single or multiple red to brown macules that can evolve into vesicular or blistering plaques. The hallmark of this diagnosis is the same-site recurrence shortly after re-exposure to the culprit drug. Perioral dermatitis (PD) is another common benign eruption occurring mostly in young-adult females. The classic clinical presentation is that of papulopustular or scaly patches most commonly around the mouth, as well as in the paranasal or periocular locations.

We report a case of a 20-year-old female suffering from an erythematous vesicular eruption involving the perioral region. She states that the rash recurs monthly, a day prior to her cycle. For her menstrual cramps, she acknowledges using an over-the-counter pain reliver containing acetaminophen, pamabrom, and pyrilamine maleat.

Spironolactone did not improve her presumed PD, and autoimmune progesterone dermatitis was excluded due to the non-classical presentation.

Therefore, to rule out FDE due to pamabrom, patch testing was performed and showed a positive reaction. To further support the diagnosis, a punch biopsy showed spongiotic dermatitis with interface changes, and a moderately dense superficial perivascular lymphohistiocytic infiltrate, with rare neutrophils and eosinophils. The overall histomorphologic and clinical features were consistent with a fixed drug eruption from pamabrom.

In conclusion, fixed drug eruption should always be in the differential diagnosis of any recurrent rash especially in patients taking over the counter medications.

Published in: ASDP 61st Annual Meeting

Publisher: The American Society of Dermatopathology
Date of Conference: November 4-10, 2024