Unexpected high prevalence of HPV 90 infection in an underserved population

Context.-Human papillomavirus 90 (HPV 90) is a rarely reported genotype worldwide, with few data available to characterize its prevalence, distribution, and disease association. Objective.-To investigate the prevalence, distribution, and disease association of HPV 90 infection in an underserved inner-city Latino opulation. Design.-Residual SurePath specimens were collected from 808 women referred for abnormal Papanicolaou tests. DNA microarray against HPV subtypes determined HPV genotypes, followed by confirmatory DNA sequencing assays. Results.-HPV 90 was detected in 32 women (4%) with an average age of 39 years (range, 23-42 years). Most women (31 of 32) had only HPV 90 infection, and one woman was coinfected with HPV 13. Two women had lowgrade intraepithelial lesion and one woman had low-grade squamous intraepithelial lesion, cannot exclude high-grade squamous intraepithelial lesion; the rest of the women had negative concurrent cytology. Available concurrent biopsies in 2 of 3 instances with abnormal cytology confirmed HPV cytopathic effect, with no high-risk HPV detected by in situ hybridization. Conclusions.-We demonstrated an unexpected, high infection rate of HPV 90 in an underserved population in the United States, with 9.4% having concurrent cytologic abnormalities. In the absence of other detectable HPV genotypes by DNA microarray, DNA sequencing, and in situ hybridization, we suspect HPV 90 may be a causative agent responsible for the concurrent cervical lesions. Because of potential shifts in HPV infection patterns in the postvaccine era, monitoring the emergence of previously underrecognized HPV genotypes is becoming increasingly important. To the best of our knowledge, this is the first study to characterize HPV 90 infection in an underserved, North American population.