HPV genotyping in anogenital abnormal samples of Ecuadorian women

Limited data are available describing human papilloma virus (HPV) genotype distributions in gynecological lesions in Ecuador. To predict how HPV vaccination and HPV-based screening will influence cervical cancer prevention it needs such studies.

We analyzed 124 samples from women, adults between 18 to 55 years old, Mestizas (Hispanics), were born and living in Quito, Ecuador. They showed an atypical sample in PapTest or a histological abnormal evaluation. We used the kit PVH Fast 2.0 with conventional PCR to study cervical and vulvar swabs prior colposcopy and/or cytology.

We found 23 different genotypes. 84/104 cases were positive for HPV (67.7%); 32/124 cases were negative (25.8%); and, in 8/124 cases (6.5%) we were unable to ascertain the existence or lack of HPV. The most common viral genotype was 6 (8.8%) followed by the 66 (4.8%) and 16, 31, 44 types (2.4% each one). Types 11, 34, 35, 54, 59, 62 and 67 showed a frequency equivalent to 1.6% each one. The remaining types showed a 0.8% frequency. Most common high-risk genotypes were 16 and 31, low-risk 6 and 41 and, the third most common group HPV type detected in this cohort was HPV 66. HPV 6 showed the highest prevalence. HPV 66 was associated with atypical cytology and was found in women with borderline cytology, low-grade lesions and high-grade lesions, but was most frequent in the threshold group. We examine a case of coexistence of 2 genotypes together 51 and 58. We found very low prevalence of HPV18 alone or HPV16/18. In 25 samples, 20.16% (25/124) we found HPV presence but we were unable to identify the genotype. We need more studies with a broad sampling to complete our geographic pattern of HPV distribution.