Natural history of human papillomavirus infection in non-vaccinated young males: low clearance probability in high-risk genotypes.

In this study, we aimed to investigate the clearance of type-specific genital human papillomavirus (HPV) infection in heterosexual, non-HPV-vaccinated males whose female partners were positive to HPV DNA tests. All consecutive men attending the same sexually transmitted diseases (STD) centre between January 2005 and December 2006 were considered for this study. All subjects (n = 1009) underwent a urologic visit and microbiological tests on first void, midstream urine and total ejaculate samples. One hundred and five patients were positive for HPV DNA (10.4 %; mean age: 34.8 ± 5.8 years) and consented to clinical examination and molecular diagnostic assays for HPV detection scheduled every 6 months (median surveillance period of 53.2 months). HPV genotypes were classified as high risk, probable high risk and low risk. HPV-positive samples which did not hybridise with any of the type-specific probes were referred to as positive non-genotypeable. At enrollment, the distribution of HPV genotypes was as follows: high-risk HPV (n = 37), probable high-risk HPV (n = 6), low-risk HPV (n = 23) and non-genotypeable HPV (n = 39). A high HPV genotype concordance between stable sexual partners emerged (kappa = 0.92; p < 0.001). At the end of the study, 71/105 (67.6 %) subjects were negative for HPV (mean virus clearance time: 24.3 months). With regard to the HPV genotype, virus clearance was observed in 14/37 (37.8 %) high-risk HPV cases, 6/6 (100 %) probable high-risk HPV cases, 20/23 (86.9 %) low-risk HPV cases and 31/39 (79.5 %) non-genotypeable cases. The high-risk HPV genotypes showed the lowest rate and probability of viral clearance (p < 0.001). In our series, high-risk HPV infections were more likely to persist over time when compared with other HPV genotypes.