Vitiligo-Like Depigmentation following Treatment with Imiquimod 5% Cream for Condylomata Acuminata

Abstract

Imiquimod cream is an immunomodulatory agent that has been approved by the US Food and Drug Administration for use in the treatment of anogenital warts (condylomata acuminata) due to its local immune effects in activating Toll-like receptors 7 and 8 on antigen-presenting cells, resulting in reduction of the viral load of human papillomavirus with subsequent wart regression. After its application, some side effects are commonly reported, including erythema, edema, scaling, erosion, and ulceration. While pigmentary changes, including vitiligo-like depigmentation, have been mentioned as a possible side effect, they have rarely been reported in the literature. Alterations in pigmentation occur because imiquimod application causes human melanocyte apoptosis and autodestruction resulting in loss of melanocytes. Herein, we report the rare case of a 34-year-old healthy male who developed vitiligo-like depigmentation following imiquimod application for his genital warts. This case report aims to increase physicians’ awareness of this possible side effect that could be irreversible and difficult for the patient to accept.

Rare Cutaneous Side Effects of Imiquimod: A Review on Its Mechanisms, Diagnosis, and Management

“…In a report by Edgar et al [ 44 ], the patient was treated externally with 5% imiquimod cream three times weekly for the left thumb and right fifth digit but developed depigmented patches on the bilateral dorsal hands and right foot. Similarly, Alatabani et al [ 31 ] reported a case of a patient who experienced depigmentation at both the treated and nontreated sites after topical treatment of genital warts with imiquimod 5% cream. Serra et al [ 36 ] reported an interesting case in which, in addition to hypopigmentation at the sites of application, the patient developed halos of hypomelanosis around multiple preexisting melanocytic nevi of the trunk following topical administration of imiquimod for vulvar condylomata.…”

“…Hypopigmentation or depigmentation is typically irreversible and may even spread. A few studies have reported varying degrees of repigmentation after discontinuation of imiquimod [ 32 , 46 ] or the topical use of 0.03% or 0.1% tacrolimus ointment [ 30 , 31 , 37 ]. Thus, when mild depigmentation occurs, prompt discontinuation and topical tacrolimus ointment may be beneficial to improve the prognosis.…”