Prevalence of occult human papillomavirus infection, determined by cytology and DNA hybridization, in heterosexual men attending a genitourinary medicine clinic.

One hundred and five heterosexual men without evidence of clinical anogenital warts and attending a genitourinary medicine clinic were studied. Three separate specimens for cytology were taken from (i) the distal urethra including the perimeatal area, (ii) the penile shaft and glans penis including the sub-preputial area, and (iii) from the anorectal area using a proctoscope. Pooled specimens of exfoliated cells from these sites were also taken for the detection of human papillomavirus (HPV) by DNA hybridization. Twenty-eight (27%) of the men had cytological evidence suggestive of HPV infection. HPV genome was detected in 21 (20%) of the men by DNA hybridization and 95% of them were carrying HPV 16 genotype either alone or in combination with other genotypes. A total of 42 (40%) of patients had evidence of occult HPV infection using cytology and/or DNA hybridization techniques collectively. None of the epidemiological risk factors were significantly associated with occult HPV infection in this study. The significance of this high incidence of sexually transmissible HPV genomes, mostly HPV16 in the anogenital area of heterosexual men attending genitourinary medicine clinics requires further study.