Dupilumab treatment of atopic dermatitis may lead to the development of dupilumab-associated facial erythema 1. There have been reports of its treatment with itraconazole 2, fluconazole 3 and ivermectin 4, with the hypothesis being that dupilumab may unmask an underlying hypersensitivity to Malassezia 5. Literature review revealed one case series of three patients with atopic dermatitis who developed acral erythema during dupilumab treatment, one of whom improved with itraconazole 6. Herein we describe a case of persistent palmar erythema improving with low-dose fluconazole. A 31-year-old male with severe whole body atopic dermatitis was treated with dupilumab 300 mg every 2 weeks. After 12 months of treatment, despite overall improvement in his atopic dermatitis, his palms started to become erythematous, scaly and dermatitic, with associated painful fissures and severe pruritus (Figure 1). This critically affected his life because he was a guitarist by occupation. On detailed history-taking, he had no exposures to suggest irritant or allergic contact dermatitis; hence patch testing was thought to be of limited utility. There was mixed growth on bacterial culture, and fungal culture was negative, noting some Malassezia species are slow-growing in culture 7. Although alternative diagnoses were considered, clinically, the appearance was not consistent with psoriasis or dyshidrotic eczema. He had mild facial erythema. There was limited improvement with topical corticosteroids, including clobetasol propionate 0.05% ointment and betamethasone dipropionate 0.05% ointment under occlusion with damp cotton gloves. However, he did note some improvement after commencement of miconazole 2% cream. We subsequently trialled clotrimazole 1%/hydrocortisone 1% cream and miconazole 2%/hydrocortisone 1% cream, but he reverted to miconazole 2% cream without topical corticosteroid as this gave the most improvement. At this time, Malassezia-specific immunoglobulin E (IgE) serum level was elevated to 1.2 kU/L (normal < 0.35 kU/L). While elevation of Malassezia-specific IgE level is not exclusive to atopic dermatitis, in dupilumab-treated atopic dermatitis patients, it has been found to be associated with the development of dupilumab-associated facial erythema 8. Given his mild partial response with topical antifungal without topical corticosteroid, he was commenced on oral antifungal, fluconazole 50 mg daily, initially for 4 weeks duration. After 4 weeks, he reported via telehealth review good improvement in the condition of his hands, followed by rapid worsening on cessation of fluconazole; hence, it was restarted. At 9 weeks, his palms were markedly less erythematous and scaly, with fewer fissures. He also had a reduction in facial erythema. At 26 weeks, his palms were slightly more scaly following a few weeks of non-adherence. He restarted and has continued fluconazole 50 mg daily for the past 8 months. He maintained stable improvement of his hand dermatitis without any adverse events, and was able to return to his occupation as a guitarist. This case suggests low-dose fluconazole may be useful for the side effect of dupilumab-associated palmar erythema, akin to its reported efficacy in the treatment of dupilumab-associated facial erythema. Notably, this patient had an elevated Malassezia-specific IgE level. Fluconazole may exhibit its effect by reducing skin colonisation with Malassezia, as well as by having inherent anti-inflammatory properties 7. In considering this potential treatment option, it is worth noting that low-dose fluconazole is well-tolerated long-term, and remains a more affordable option than itraconazole in the Australian context. Open access publishing facilitated by The University of Sydney, as part of the Wiley - The University of Sydney agreement via the Council of Australasian University Librarians. The authors have nothing to report. The authors obtained the patient's consent to publish this case. The authors declare no conflicts of interest. The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to privacy or ethical restrictions.
Selvaraj et al. (Mon,) studied this question.