The Imiquimod Flare: A Unique Case Report of Generalized Lymphadenopathy with Topical Imiquimod for HPV 16-Induced Vulval High-Grade Squamous Intraepithelial Lesion.

Abstract

Introduction: Concomitant vulval high-grade squamous intraepithelial lesion (HSIL) and cervical intraepithelial neoplasia (CIN) have rarely been associated in a young woman and should prompt investigation for high-risk Human Papillomavirus (HPV). Conservative treatment strategies for vulval HSIL typically range from skinning vulvectomy to topical applications of immunomodulator creams. Imiquimod 5% topical application has been associated with local side effects, including itching and burning. Systemic side effects are extremely rare. The authors report a unique case of generalized lymphadenopathy following topical application of imiquimod 5%.

Case presentation: A 32-year-old, nulligravida woman of Asian ethnicity presented with subfertility. Incidentally, her general examination showed the presence of raised, multifocal, maculopapular lesions (Bowenoid papulosis) with biopsy showing usual-type vulval high-grade squamous intraepithelial lesion (HSIL). After a brief application of topical imiquimod 5%, she developed sudden, tender generalized lymphadenopathy. Aspiration cytology showed caseation necrosis, and she was hence started on anti-tubercular therapy. Resolution of lymphadenopathy was observed at the one-month follow-up.

Discussion: This is the first reported case of acute, tender generalized lymphadenopathy with topical imiquimod in a patient with CIN and vulval HSIL. The underlying mechanism involves alteration of cell-mediated immunity, and the resultant likely functional maturation of epidermal Langerhans cells in vivo is hypothesized. This forms an alternative to surgery, as it is a convenient, self-administered modality that does not affect psychosexual health. Additionally, it has been implicated in HPV virus clearance, unlike surgery, and was hence recommended in this case.

Conclusion: This report underscores this rare phenomenon that can pose a significant therapeutic challenge to clinicians, necessitating regular and long-term follow-up.