Comparison of conventional cervical cytology versus visual inspection with acetic acid (VIA) among HIV-infected women in western Kenya

Objective: To determine the accuracy of visual inspection with Acetic Acid (VIA) versus conventional Pap smear as a screening tool for cervical intraepithelial neoplasia (CIN)/cancer among HIV-infected women. Materials and Methods: 150 HIV-infected women attending the Moi Teaching and Referral Hospital HIV clinic in Eldoret underwent conventional Pap smear, VIA, colposcopy and biopsy. VIA and Pap smears were done by nurses while colposcopy and biopsy were done by a physician. Receiver Operating Characteristic (ROC) analysis was conducted to compare the accuracies between VIA and Pap smear in sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). Results: Among the study participants: VIA was abnormal in 55.3% (83/150, CI=47.0–63.5%); Pap smear showed atypical squamous cells of undetermined significance (ASCUS) or worse in 43.7% (59/135, CI=35.2–52.5%) and 10% (15/150) of the Pap smears were unsatisfactory. Of the abnormal Pap smears, 3% (2/59) had ASCUS, 7% (4/59) had ASC-high grade, 60% (35/59) had low-grade squamous intraepithelial lesions (SIL), 29% (17/59) had high grade SIL, and 2% (1/59) was suspicious for cervical cancer. Using cervical intraepithelial neoplasia (CIN) 2 or higher disease on biopsy as an end point, VIA has a sensitivity of 69.6% (CI=55.1–81.0%), specificity of 51.0% (CI=41.5–60.4%), PPV of 38.6% (CI=28.8–49.3%) and NPV of 79.1% (CI=67.8–87.2%). For conventional Pap smear, sensitivity was 52.5% (CI=42.1–71.5%), specificity 66.3% (CI=52.0–71.2%), PPV 39.7% (CI=27.6–51.8%), and NPV 76.8% (CI=67.0–85.6%). Conclusion: VIA is comparable to Pap smear and acceptable for screening HIV-infected women in resource limited settings such as Western Kenya