HUMAN PAPILLOMAVIRUS DETECTION IN RESIDUAL SAMPLES FROM STI TESTS IN MEN WHO HAVE SEX WITH MEN

Background Anorectal swab specimens, either alone, or pooled with first catch urine (FCU) and pharyngeal swab specimens, are used to test for STIs in MSM. The residual sample, after routine testing, may be used to monitor human papillomavirus (HPV) prevalence in this population, but the sensitivity of HPV detection in such specimens is unknown. Methods MSM attending a UK sexual health clinic were consented to collect additional specimens to compare the detection of HPV in a dedicated swab, with detection in a residual anorectal and/or pooled specimen. All subjects provided 3 specimens: (i) anorectal swab (for chlamydia(CT)/gonorrhoea(GC) testing); (ii) pooled anorectal/pharyngeal/FCU specimen (for GC/CT); (iii) dedicated anorectal swab for HPV. Specimen (iii) and residual material from specimens (i) and (ii) were tested for type-specific HPV DNA (19 confirmed/possible high-risk (HR) genotypes and genotypes 6/11). HPV detection was by in-house multiplex PCR and Luminex-based genotyping assay. Results 129 MSM were recruited; mean age 38.1 years; 24% were HIV-positive. 92/129 (71%) had type-specific HPV DNA detected in ≥1 specimen; 80/129 (62%) had HR-HPV. 70/123 participants (56.9%) with sufficient residual pooled specimen, and a dedicated HPV specimen had detectable HPV on both and 40 (32.5%) were HPV-negative on both; overall concordance 89% (95%CI 83,94). Prevalence in pooled samples was 4.1% (-1.9,10.0) higher than dedicated samples. 74/125 participants (59.2%) with sufficient residual anorectal specimen, and dedicated anorectal HPV specimen had detectable HPV on both and 36 (28.8%) were HPV-negative on both; overall concordance 88% (81,93). Prevalence in residual samples was 5.6% (-0.6,11.8) higher than dedicated samples. Conclusion Residual anorectal and pooled STI test specimens offer comparable sensitivity to anal HPV swab samples, which are typically used in prevalence studies. This supports use of residual samples to monitor HPV prevalence, as currently proposed in the UK to evaluate the impact of targeted MSM HPV vaccination. Disclosure No significant relationships.