Surepath liquid based pap test

Vaginal samples were collected by trained gynecologists. The procedure began by removing the cervical mucus with a sterile swab. Furthermore, endocervical and exocervical epithelia were gathered with a cervix examination brush (Rovers Cervex-Brush; Rovers Medical Devices B.V., Oss, The Netherlands). Additionally, the pH of the mucus samples was determined from the vaginal swab using a pH test strip (MColorpHast; Merck-Millipore, Burlington, MA, USA). The detachable head of the cervix examination brush was preserved in a liquid vial (BD SurePath™ liquid-based Pap test; BD Biosciences, San Jose, CA, USA) and transported under refrigeration conditions (4 °C). The samples were stored at −40 °C for 5 h until DNA extraction.

Four hundred and eighty women were screened for LSIL, including cervical intraepithelial neoplasia grade 1 (CIN1); HSIL, including CIN2/3; and ICC, through visual inspection with acetic acid (VIA) and Lugol according to WHO guidelines [31 ,32 (link)]. In addition, endocervical samples were collected for HPV testing and characterization. Specimens were collected using BD SurePath™ liquid-based Pap test and shipped to Clinica Universidad de Navarra (Pamplona, Spain), where they were stored at 4 °C until further use.

An automated liquid-based cytology, SurePath™ liquid-based Pap test (BD, USA), was employed for cytological sample preparation. After removing obscuring mucus from the cervix with a cotton swab, endocervical and ectocervical cells were collected with cytobrush. This cytobrush was immediately rinsed in a vial containing SurePath Preservative Fluid. Samples were transported at room temperature for analysis at the International Clinical Laboratories (ICL) in Addis Ababa using BD PrepMate™ and PrepStain™ Slide Processor. Vials containing samples were labeled and placed into the BD PrepMate™ Slide Processor in which a liquid-based filtration process removed mucus and debris, preserving cell morphology, and making a smear of even distribution. All slides were stained with the BD SurePath Kit Cytology Stain and examined by two pathologists [7 (link)] who were enrolled in the College of American Pathologists (CAP) proficiency program and received stained LBC slides every three months as well as participating in the external quality assurance scheme. LBC test results were recorded based on the Bethesda gynecologic cytology guideline [8 (link)].