Phylogenetic classification of human papillomavirus genotypes in high-grade cervical intraepithelial neoplasia in women from a densely populated Brazilian urban region

context and objective: differences in human papillomavirus (hpv) types may correlate with the biological potential and invasion risk of high-grade cervical intraepithelial neoplasia (cin 2 and cin 3). the objective of this study was to determine the relationship between different combinations of hpv types and cin severity. design and setting: cross-sectional study, at universidade estadual de campinas (unicamp). methods: cervical samples from 106 women treated due to cin 2 (18) or cin 3 (88) were examined for specific hpv genotypes using roche linear array？ (la-hpv). the proportions of cin 2 and cin 3 in groups of women infected with the hpv phylogenetic groups a7 and a9 were compared. three groups were formed: women with single infections; multiple infections; and the whole sample. results: multiple infections were detected in 68 samples (64.7%). the most frequent high-risk genotypes detected (single/multiple) were hpv 16 (57.1%), hpv 58 (24.7%), hpv 33 (15.2%), hpv 52 (13.3%), hpv 31 (10.4%), hpv 51 (7.6%) and hpv 18 (6.6%). women without infection with hpv species alpha 9 were less likely to have cin 3 than were their alpha 9 hpv-infected counterparts. hpv 16 and/or hpv 18, with or without associations with other viral types, were more frequently found in women with cin 3 than in those with cin 2. conclusions: the severity of high-grade cin may be aggravated by the presence of hpv types included in the alpha 9 phylogenetic classification and by infections including hpv 16 and 18, singly or in combination with other hpv genotypes.