Cross-Sectional Analysis of Human Papillomavirus Infection and Cytological Abnormalities in Brazilian Women

Abstract

The aim of this study was to determine the incidence of infections and cytological abnormalities and to investigate possible predisposing factors such as sociodemographic characteristics, sexual behavioral habits, and gynecological and obstetric backgrounds. Between 2013 and December 2016, a cross-sectional study was conducted among 429 consenting women, from whom cervical samples were tested for the presence of Human papillomavirus (HPV) by polymerase chain reaction (PCR). Susceptibility to HPV infection was assessed by binary logistic regression in light of possible predisposing factors, which were collected using a questionnaire. In our sample population, the prevalence of HPV infection was 49%; high-risk types had a higher prevalence of 89.1%. A larger proportion of HPV-infected women were under 25 years of age, were single, and had monthly incomes up to minimum wage. Multivariate binary logistic regression analysis showed that age younger than 25 years increased the odds of infection fivefold, while a monthly income of one to three minimum wages provided protection against HPV infection, even if the women were married or had a cohabiting partner. In the HPV-positive group, squamous intraepithelial lesions (SIL) occurred more frequently in women who earned up to one minimum wage monthly, but a monthly income of one to three minimum wages protected against the development of SIL. The results suggest that age, marital status, and monthly income are important cofactors for HPV infection and the development of SIL.

Chlamydia trachomatis enhances HPV persistence through immune modulation

“…In coinfection of CT with HPV, the persistent infection of HPV is enhanced [ 30 , 31 ]. The co-infection with C. trachomatis and HPV (especially the 16, 18, 31, 33, 53, and 56 genotypes) is considered the most important risk factor for the presence of cervical cancer [ 32 , 33 ].…”

“…Chronic CT infection can cause persistent HPV infection by reducing antigen-presenting cells and inhibiting cell-mediated immunity [ 31 , 32 ].…”

Alterations of Vaginal Microbiota and Chlamydia trachomatis as Crucial Co-Causative Factors in Cervical Cancer Genesis Procured by HPV

“…A vagina with a pH of 4.5 or below serves as a protective shield against harmful pathogens that are unable to survive in such an acidic environment. When the pH is elevated (alkaline), harmful bacteria gain an opportunity to move in and disrupt the vaginal ecosystem [ 20 , 21 , 22 ].…”

“…Therefore, any changes in local balance homeostasis and in pH may have a direct, negative impact on the mucosa integrity that is functional to the outside and inside permeability gradient [ 21 , 22 ]. Once broken, the mucosa and tissues become an easy target of aggressive microorganisms and inflammatory processes that accelerate the deterioration process of both the endothelial wall and microbiota shield, enhancing the accumulation of pro-inflammatory endotoxins and long-term pathogen allocation ( Figure 3 ) [ 20 , 21 , 22 ].…”

“…The outcomes on the female genital tract, either on the vaginal or cervical microbiota, together with a substantial cytokine profile have identified the changes in microbiota diversity among women affected by HPV and C. trachomatis infection with bacteria/viral vaginosis (BVV) [ 28 , 29 , 30 , 31 ]. The co-infection with C. trachomatis and HPV (especially the 16, 18, 31, 33, 53, and 56 genotypes) is considered the most important risk factor for the presence of CC, especially in young, unmarried women who started their sex lives early with several sexual partners and who used oral contraceptives [ 14 , 15 , 16 , 22 ]. Interestingly, from these studies, the prevalence of C. trachomatis was high, predominantly in young women [ 14 , 15 , 16 ].…”