Impact of intralesional tuberculin PPD injection on anogenital warts: Interferon-α, interleukin-2, and treatment outcomes

The clinical manifestation of anogenital warts (AGW) resulting from Human Papillomavirus (HPV) infection is influenced by host immune responses. Interferon (IFN)-α contributes to antiviral activity, while Interleukin (IL)-2 plays an important role in cellular immunity. Tuberculin purified protein derivative (TPPD) has been investigated as an immunotherapeutic agent. This exploratory quasi-experimental study analyzed 12 AGW patients treated with intralesional TPPD (5 tuberculin units weekly for six injections). Tissue samples were collected at baseline and week 2, and serum samples at baseline and week 6. IFN-α and IL-2 expression in tissue was assessed using immunohistochemistry (IHC), and serum levels were measured using ELISA. TPPD therapy was associated with increased IFN-α and IL-2 expression in tissue (p = .047 and p = .019) and higher serum IL-2 levels (p = .030), while serum IFN-α did not change significantly. Clinically, 4 of 12 patients achieved complete response, whereas others showed partial, minimal, or no improvement, and 6 patients required subsequent destructive treatment. Local and systemic cytokine changes did not correlate with lesion regression. These findings suggest that cytokine upregulation reflects immune activation rather than determining lesion clearance, and between-group comparisons should be interpreted cautiously due to baseline.