HPV 16 and 18 viral loads are greater in patients with high-grade cervical epithelial lesions

Background: Cervical cancer is the second most common cancer in women worldwide. High-risk infection with HPV type 16 or type 18 is the most important risk factor associated with the development of cervical cancer. Aims: To determine the viral load of HPV-16 and HPV-18 in samples from women with cervical epithelial lesion in the State of Colima, Mexico. Materials and Methods: A crosssectional analytic study was conducted that included 45 samples positive for HPV-16 and 45 samples positive for HPV-18 from patients with cervical cancer or precursor lesion. Real time PCR was employed to determine the number of copies /10³ cells. Viral load was determined in the two groups of patients and correlated with tumor grade. Results: THe authors found that the HPV-16 viral load was greater than that of HPV-18 through a Mann-Whitney U analysis, resulting in a p = 0.000; as the malignancy of the cervical lesion progressed, the viral load increased, and HPV-16 showed a moderate positive association with an r = 0.509 and a p = 0.000, whereas HPV-18 showed a weak positive correlation with an r = 0.372 and a p = 0.012. Conclusions: The viral load of HPV-16 was greater than that of HPV-18. The HPV-16 viral load had a moderate positive association in relation to cervical lesion severity, whereas the viral load of HPV-18 had a weak positive correlation with respect to the cervical lesion grade.

Human papillomavirus; Viral load; Cervical lesion.

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