Objectives: Rectal swab specimens, either alone or pooled with first-void urine (FVU) and pharyngeal swab specimens, are used to test for Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infection in men who have sex with men (MSM). Following introduction of human papillomavirus (HPV) vaccination for MSM attending UK sexual health services (SHSs), HPV testing of residual CT/NG test specimens has been proposed to monitor HPV prevalence in this population. Performance of HPV detection in such specimens has not been evaluated previously.
Methods: MSM attending a UK SHS provided three specimens: (1) rectal swab for CT/NG, (2) pooled rectal/pharyngeal/FVU specimen for CT/NG and (3) dedicated anal swab for HPV. Specimen 3 and residual material from specimens 1 and 2 were tested for type-specific HPV DNA. HPV detection was by an in-house multiplex PCR and luminex-based genotyping assay.
Results: A total of 129 MSM were recruited with a mean age of 38.1 years; 24% were HIV-positive. Of the 129 MSM, 92 (71%) had any type-specific HPV DNA in ≥1 specimen; 80 (62%) had high risk (HR) HPV. Of 123 participants with sufficient residual pooled and dedicated specimens, 70 (56.9%) had detectable HPV on both, and 40 (32.5%) were negative on both; overall concordance was 89% (95% CI 83% to 94%), and kappa statistic was 0.78 (95% CI 0.66 to 0.89). Pooled samples had a 4.1% (95% CI-1.9% to 10.0%) higher test positivity rate than dedicated samples. Of 125 participants with sufficient residual rectal and specimens, 74 (59.2%) had detectable HPV on both, and 36 (28.8%) were negative on both; overall concordance was 88% (95% CI 81% to 93%), and kappa statistic was 0.74 (95% CI 0.61 to 0.86). Residual rectal samples had 5.6% (95%CI-0.6% to 11.8%) higher test positivity than dedicated samples.
Conclusions: We observed high concordance between the dedicated and residual STI test specimens. Our data support the strategy of testing residual specimens for HPV prevalence monitoring in MSM to evaluate the impact of the targeted vaccination programme.
- anogenital cancer
- anogenital conditions