Carga viral de seis tipos de Virus del Papiloma Humano de alto riesgo y su asociacion con lesiones cervicales

Abstract

Background: Infection with high risk of human papillomavirus (HR-HPV) is the main factor in the development of Cervical Cancer (CC). Viral load can modulate this relationship, so it is important to quantify and establish its association with CC precursor lesions.

Methods: 60 women having cervical intraepithelial neoplasia (CIN) and 120 women without CIN and confirmed by colposcopy, were included in the study. Samples were tested for six high-risk HPV types to determine viral copy number by real-time PCR. Crude and adjusted odds ratios (ORa) were estimated for evaluating the association between each viral type’s DNA load and the risk of cervical lesions occurring.

Results: 93.22% of women with CIN and 91.23% negative women were positive for at least one type of HPV. HPV-18 and HPV-16 were the most prevalent types, with HPV-31 in women without CIN. No statistically significant differences in viral load between these two groups were identified, although a higher viral load was observed in CIN regarding some viral types. Lesions were more frequent in HPV-16 patients having a low viral load (3.53 ORa, 1.16-10.74 95%CI) compared to those having high HPV-16 load (2.62 ORa, 1.08-6.35 95%CI). High viral load in HPV-31 patients was associated with lower CIN frequency (0.34 ORa, 0.15-0.78 95%CI).

Conclusions: The type-specific prevalence of HPV is consistent with the reported worldwide. An association between HPV DNA load and CIN frequency was seen to be type-specific and may have depended on the duration of infection, high viral loads related to transient infections and low viral loads with persistent infections. This analysis has provided information for understanding the effect of HPV DNA load on cervical lesion development. However prospective studies are needed.