Detection of Incident Anal High-Risk Hpv-Dna in Msm: Incidence or Reactivation?

Abstract

Background: We aimed to assess whether sexual exposure may explain all incident anal HPV detections among men who have sex with men (MSM). Methods: A longitudinal study among MSM was conducted between 2010 and 2013 with six-monthly visits and up to 24 months of follow-up. Risk-factor questionnaires, blood samples, and anal and penile self-swabs were collected at each visit. Self-swabs were used for detection and genotyping of HPV by SPF10-PCR/DEIA/LiPA25 system. Serum samples were tested for high-risk (hr)HPV antibodies. Incident anal HPV detection rates among sexually non-, low and highly exposed MSM were compared. Factors associated with incident anal hrHPV detection were assessed using multivariable Cox regression. Results: 714 men (median age 40 years; 39% HIV positive) were included in the analysis. Incident anal detections of all hrHPV-types were observed among both sexually non-exposed and exposed MSM. In multivariable analyses, highly sexually exposed, being HIV-infected and having a penile HPV infection were positively associated with incident anal HPV detection; those reporting more sex partners had a non-significantly increased risk of HPV detection. Conclusion: Incident anal hrHPV detection is common among recently non-exposed MSM, suggesting that a reactivated latent HPV infection instead of an incident infection may underlie incident HPV detection.