Diagnostic accuracy and practicability of the VISITECT® advanced HIV disease CD4 test compared to the Partec® CyFlow Counter II for CD4 enumeration in Nigeria’s HIV program

We evaluated the diagnostic performance and practicability of the VISITECT ® CD4 Lateral Flow Assay for identifying advanced HIV disease (AHD) across 13 facilities in Nigeria. In two phases, 468 participants were tested with VISITECT ® CD4 and Partec ® CyFlow. VISITECT ® CD4 achieved a sensitivity of 100.0% and specificity of 89.8% for detecting CD4 ≤ 200 cells/mm 3 . The positive predictive value (PPV) was 91.3% (95% CI: 87.4–94.1), and the negative predictive value (NPV) was 100% (95% Cl: 98.1–100.0). Overall diagnostic accuracy was 95.1% (95% CI: 92.8–96.8). These findings support the use of VISITECT ® CD4 as a complementary point-of-care tool to strengthen timely identification of advanced HIV disease within decentralized health systems. While not a substitute for flow cytometry, its high sensitivity and operational feasibility make it well suited for triage and early clinical decision-making in resource-limited settings.