ABSTRACT
Introduction
CD4 testing plays an important role in clinical management and epidemiological surveillance of HIV disease. Rapid, point-of-care (POC) CD4 tests can improve patients’ access to CD4 testing, enabling decentralization of HIV services.
Areas covered
We conducted a profile review of the Visitect®CD4 and the Visitect®CD4 Advanced Disease (Omega Diagnostics, UK) – the two lateral flow, equipment-free POC CD4 tests, which can be used to identify people with HIV who have CD4 of less than 350 and 200 cells/μl, respectively. Using published data from independent studies, we discussed the performance and utility of these tests, highlighting the advantages as well as their limitations.
Expert opinion
The tests are user-friendly, acceptable to health care workers, and feasible to implement in primary health care settings and can provide reliable results for clinical decision-making. Hands-on training with pictorial instructions for use is needed to enhance test’s operator confidence in interpretation of test results. Quality assurance program should be in place to ensure the quality of testing. Development of a next-generation test with a cutoff of 100 cells/μl is recommended to identify patients with advanced immunosuppression for initiation of prophylaxis to reduce HIV-related death. Operational research is also needed to identify cost-effective implementation strategies in real-world settings.
Article highlights
CD4 testing plays a critical role in clinical management and epidemiological surveillance of HIV disease. Rapid, point-of-care (POC) CD4 tests can improve patients’ access to CD4 testing, enabling decentralization of HIV services.
The Visitect®CD4 and the Visitect®CD4 Advanced Disease (Omega Diagnostics, UK) are the two semiquantitative, equipment-free POC CD4 tests, currently available on the market.
The Visitect®CD4 and the Visitect®CD4 Advanced Disease can provide onsite visual results to identify patients with late diagnosis (CD4<300 cells/μl) or advanced HIV disease (CD4<200 cells/μl), respectively, for prioritizing treatment initiation and/or provision of an enhanced package of care, without the need for venepuncture, electricity supply, or battery-operated equipment.
Limitations of the tests include three different incubations/waiting times (3’, 17’, and 20’) during the testing procedure, which may require a dedicated test operator to ensure the quality of the testing and the validity of test results for clinical decision-making at the primary health care level.
Development of a 100 cells/μl cutoff test (for identification of patients with advanced immunosuppression for interventions to reduce HIV-related death) is recommended. Operational research is needed to guide cost-effective implementation in real-world settings.
Acknowledgment
The author greatly acknowledge the contribution to this work of the Victorian Operational Infrastructure Support Program received by the Burnet Institute.
Declaration of Interest
MD Pham works at the Burnet Institute where the Visitect CD4 test was developed and has involvement in evaluation studies in South Africa and India. M Stoove works at the Burnet Institute. S Crowe codeveloped the Visitect CD4 test at the Burnet Institute and has involvement in evaluation studies in South Africa and India. S Luchters led the Visitect CD4 evaluation study in South Africa and has involvement in the evaluation study in India. D Anderson codeveloped the Visitect CD4 test at the Burnet Institute and has involvement in evaluation studies in South Africa and India. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.
Reviewer disclosures
Peer reviewers of this manuscript have no relevant financial or other relationships to disclose.
Supplementary material
Supplemental data for this article can be accessed here