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

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.