Diagnostic accuracy of the Xpert HPV assay in women starting antiretroviral treatment in South Africa

Background Human papillomavirus (HPV) associated cervical cancer remains the leading cause of cancer mortality among women in resource-limited settings. The WHO recommends HPV screening with a high-performance screening test for women by age 35 and 45 years. We compared the Cepheid Xpert HPV test to the hybriSpot laboratory-based assay among women living with Human Immunodeficiency Virus (WLHIV) starting antiretroviral treatment (ART). Methods In this cross-sectional analysis we performed a rapid Xpert HPV test on an endocervical liquid-based cytology (LBC) sample, which detects 14 high-risk HPV (hr-HPV) subtypes (HPV16, HPV18/45, P3 : HPV31, 33, 35, 52, 58; P4: HPV51, 59; P5: HPV39, 56, 66, 68). The LBC samples were also tested on the hybriSpot platform (Vitro S.A., Master Diagnostica, Sevilla, Spain), which distinguishes between the same hr-HPV subtypes and an additional 21 high- and low-risk HPV subtypes. Results Among 47 WLHIV included, the median age was 32 [Interquartile Range 28–39] years, and mean CD4 count 338 cells/µl. Overall, 32 (68%) WLHIV were positive for hr-HPV on the Xpert assay and 35 (74.5%) WLHIV were positive on the hybriSpot platform. Agreement between the Xpert and hybriSpot tests was good (kappa co-efficient ≥0.75) for the detection of HPV16, HPV18/45 and other hr-HPV subtypes, except for hr-HPV subtypes 51, 59 (kappa co-efficient 0.56). High sensitivity (>90%) was observed only for the P3 (HPV 31, 33, 35, 52, 58) and P4 (HPV39, 56, 66, 68) channels, while specificity exceeded 90% for all channels except P4. Among P3 HPV subtypes, particularly HPV52, prevalence was high in this subset as detected by the hybriSpot assay. Conclusions The Xpert HPV test demonstrated high agreement when compared to a laboratory PCR-based reverse dot-blot hybridisation assay among WLHIV at ART initiation. Near point-of-care HPV testing may be beneficial where HPV screen-and-treat models can be integrated into routine HIV care.