High frequency of genital human papillomavirus infections and related cervical dysplasia in adolescent girls in Belgium

Human papillomavirus (HPV) infections are causally related to cervical cancer and a range of other diseases, both in adults and in minors. Information on the frequency of genital HPV infections in adolescents is sparse. The aim of this study was to gain insight into the genotype-specific distribution of HPV genotypes in patients younger than 18 years of age. This observational retrospective study included 4807 samples of patients presenting for opportunistic screening in Belgium between June 2006 and January 2012. For statistical analysis, only the first visits of patients were withheld, reducing the sample to 4180. Samples were collected in liquid-based cytology medium and analyzed using a series of genotype-specific real-time PCR reactions. Cytology was read with previous knowledge of HPV infection and scored using the Bethesda classification. The mean age was 16.9 years. Most youngsters had no complaints (88.4%), were using hormonal contraception (79.5%), and clinical examination did not show any abnormalities (96.0%). The overall HPV frequency was 15.7%, with the most frequently found types being HPV16 (16.7%), HPV51 (14.6%), HPV66 (10.4%), HPV31 (9.9%), and HPV39 (9.1%). More than one-third (39.0%) of the infected girls harbored an infection with at least two HPV genotypes. Cytological abnormalities were found in 8.2% of samples. L-SIL (4.2%) was most frequently observed, followed by ASC-US (3.6%), HSIL (0.3%), and ASC-H (0.1%). The severity of lesions worsened with increasing age. Our findings indicate that an aberrant HPV genotype profile can be found in adolescent girls; moreover, this group shows a high rate of cervical abnormalities.