Accuracy of screening tests for cervical precancer in women living with HIV in low-resource settings: a paired prospective study in Lusaka, Zambia

Abstract

Objective This study aimed to provide evidence to improve cervical screening for women living with HIV (WLHIV). We assessed the accuracy of screening tests that can be used in low-resource settings and give results at the same visit.Methods and analysis We conducted a paired, prospective study among consecutive eligible WLHIV, aged 18–65 years, receiving cervical cancer screening at one hospital in Lusaka, Zambia. The histopathological reference standard was multiple biopsies taken at two time points. The target condition was cervical intraepithelial neoplasia grade 2 and above (CIN2+). The index tests were high-risk human papillomavirus detection (hrHPV, Xpert HPV, Cepheid), portable colposcopy (Gynocular, Gynius) and visual inspection with acetic acid (VIA). Accuracy of stand-alone and test combinations were calculated as the point estimate with 95% CIs. A sensitivity analysis considered disease when only visible lesions were biopsied.Results Women included in the study had well-controlled HIV infection (median CD4 count=542 cells/mm3) and all except one were on antiretroviral therapy. Among 371 participants with histopathological results, 27% (101/371) women had CIN2+ and 23% (23/101) were not detected by any index test. Sensitivity and specificity for stand-alone tests were: hrHPV, 67.3% (95% CI 57.7% to 75.7%) and 65.3% (95% CI 59.4% to 70.7%); Gynocular 51.5% (95% CI 41.9% to 61.0%) and 80.0% (95% CI 74.8% to 84.3%); and VIA 22.8% (95% CI 15.7% to 31.9%) and 92.6% (95% CI 88.8% to 95.2%), respectively. Combining tests did not improve test accuracy measures. All test accuracies improved in sensitivity analysis.Conclusion The low accuracy of screening tests assessed might be explained by our reference standard, which reduced verification and misclassification biases. Better screening strategies for WLHIV in low-resource settings are urgently needed.Trial registration number NCT03931083.