Comparison of AmpFire and MY09/11 assays for HPV genotyping in anogenital specimen of Rwandan men who have sex with men.

Introduction: The AmpFire HPV genotyping Assay (Atila Biosystems, Mountain View, CA, USA) is a new test for which there are few data regarding its analytic performance and reliability. Using anal and penile swab specimens from a cohort study of men who have sex with men (MSM) in Rwanda, we compared high-risk HPV (hrHPV) detection by AmpFire done at two laboratories, one at University of California San Francisco (UCSF) and the other Rwanda Military Hospital, and well-validated MY09/11-based assay done at UCSF.

Methods: Anal and penile specimens collected from 338 MSM from March 2016 to September 2016 were tested for high-risk HPV genotypes (hrHPV) by MY09/11, AmpFire UCSF and AmpFire RMH. Cohen's kappa coefficient was used to test for reproducibility.

Results: The hrHPV positivity by MY09/11 and AmpFire UCSF was 13% and 20.7% (k = 0.73) for anal specimens and was 26.3% and 32.6% (k = 0.67) for penile specimens. Specifically, good reproducibility was for types 16 and 18 (k = 0.69 and k = 0.71) for anal specimens and (k = 0.50 and k = 0.72) for penile specimens. The hrHPV positivity by AmpFire at UCSF and RMH was 20.7% for both laboratories (k = 0.87) for anal specimens and was 34.9% and 31.9% (k = 0.89) for penile specimens. Specifically, excellent reproducibility was for types 16 and 18 for anal specimens (k = 0.80 and k = 1.00) and penile specimens (k = 0.85 and k = 0.91).

Conclusion: Results show that MY09/11 and AmpFire assays have good reproducibility while the AmpFire UCSF and RMH assays have excellent reproducibility. These results show that AmpFire is a promising HPV genotyping test.