Tipagem e estado físico de papilomavírus humano por hibridização in situ em lesões intra-epiteliais do colo uterino

A simple HPV 18 detection method based on ultra specific primer immobilized on glass slides

This study was carried out to develop a simple and inexpensive method for detection of Human papillomavirus (HPV 18) based on irreversible immobilization of ultra specific primer on silanized glass slides. This method is revealed by Blue Green Loading Dye I (LGC) and compared with conventional polymerase chain reaction (PCR) for endocervical samples. The new method was tested in 40 DNA samples with precancer uterine lesions of women treated in Hospital of Recife PE, Brazil. DNA samples were extracted using Wizard Genomic DNA Purification Kit according to manufacturer's instructions. The samples were tested for HPV 18 by conventional PCR (PCRc) and the products visualized on 1.2% agarose gel, with LGC under UV 260 nm. After that the positive and negative samples to HPV 18 were tested by immobilization method and the results visualized with LGC under UV 260 nm. Both PCRc and immobilization method showed high degree of correlation (95%), whereas comparison between PCRc and immobilization method showed good correlation (100%). PCRc is widely known for detection of HPV because of its high sensitivity and efficiency, but due to high cost it is not yet standardized for use in public health laboratories. In our study, the single-stranded DNA immobilized method on a glass slide was effective in screening for HPV revealed by Blue Green and may be an alternative method for diagnosis of HPV once it offers a fast, and easy handling.

Type-specific HPV prevalence in cervical cancer and high-grade lesions in Latin America and the Caribbean: systematic review and meta-analysis

Background

Cervical cancer is a major public health problem in Latin America and the Caribbean (LA&C), showing some of the highest incidence and mortality rates worldwide. Information on HPV type distribution in high-grade cervical lesions (HSIL) and invasive cervical cancer (ICC) is crucial to predict the future impact of HPV16/18 vaccines and screening programmes, and to establish an appropriate post-vaccinal virologic surveillance. The aim was to assess the prevalence of HPV types in HSIL and ICC in studies in LA&C.

Methods and Findings

We performed a systematic review, following the MOOSE guidelines for systematic reviews of observational studies, and the PRISMA statement for reporting systematic reviews and meta-analyses. Inclusion criteria were at least ten cases of HSIL/ICC, and HPV-type elicitation. The search, without language restrictions, was performed in MEDLINE, Cochrane Library, EMBASE, LILACS from inception date to December 2009, proceedings, reference lists and consulting experts. A meta-analysis was performed using arc-sine transformations to stabilize the variance of simple proportions. Seventy-nine studies from 18 countries were identified, including 2446 cases of HSIL and 5540 of ICC. Overall, 46.5% of HSIL cases harbored HPV 16 and 8.9% HPV18; in ICC, 53.2% of cases harbored HPV 16 and13.2% HPV 18. The next five most common types, in decreasing frequency, were HPV 31, 58, 33, 45, and 52.

Study's limitations comprise the cross-sectional design of most included studies and their inherent risk of bias, the lack of representativeness, and variations in the HPV type-specific sensitivity of different PCR protocols.

Conclusions

This study is the broadest summary of HPV type distribution in HSIL and ICC in LA&C to date. These data are essential for local decision makers regarding HPV screening and vaccination policies. Continued HPV surveillance would be useful, to assess the potential for changing type-specific HPV prevalence in the post-vaccination era in Latin America.