The BD FACSPresto Point of Care CD4 Test Accurately Enumerates CD4+ T Cell Counts

• Published in: PloS one 2015-12, Vol.10 (12), p.e0145586-e0145586
• Main Authors: Bwana, Priska, Vojnov, Lara, Adhiambo, Maureen, Akinyi, Catherine, Mwende, Joy, Prescott, Marta, Mwau, Matilu
• Format: Article
• Language: English
• Subjects: Acquired immune deficiency syndrome; Adult; AIDS; Antiretroviral agents; Antiretroviral drugs; Antiretroviral therapy; Blood Specimen Collection - methods; CD4 antigen; CD4 Lymphocyte Count - methods; CD4-Positive T-Lymphocytes - immunology; Coefficient of variation; Cross-Sectional Studies; Developing Countries; Evaluation; Female; Fungal infections; Health care; Health Facilities; HIV; HIV Infections - immunology; HIV Seropositivity - immunology; Human immunodeficiency virus; Humans; Laboratories; LDCs; Lymphocytes T; Male; Measurement; Medical diagnosis; Medical personnel; Medical tests; Middle Aged; Patients; Physiologic monitoring; Point-of-Care Systems - standards; Prospective Studies; Sensitivity; Sensitivity and Specificity; Systematic review; T cells; Technicians; Technology
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0145586

Currently 50% of ART eligible patients are not yet receiving life-saving antiretroviral therapy (ART). Financial constraints do not allow most developing countries to adopt a universal test and offer ART strategy. Decentralizing CD4+ T cell testing may, therefore, provide greater access to testing, ART, and better patient management. We evaluated the technical performance of a new point-of-care CD4+ T cell technology, the BD FACSPresto, in a field methods comparison study. 264 HIV-positive patients were consecutively enrolled and included in the study. The BD FACSPresto POC CD4+ T cell technology was placed in two rural health care facilities and operated by health care facility staff. We compared paired finger-prick and venous samples using the BD FACSPresto and several existing reference technologies, respectively. The BD FACSPresto had a mean bias of 67.29 cells/ul and an r(2) of 0.9203 compared to the BD FACSCalibur. At ART eligibility thresholds of 350 and 500 cells/ul, the sensitivity to define treatment eligibility were 81.5% and 77.2% and the specificities were 98.9% and 100%, respectively. Similar results were observed when the BD FACSPresto was compared to the BD FACSCount and Alere Pima. The coefficient of variation (CV) was less than 7% for both the BD FACSCalibur and BD FACSPresto. CD4+ T cell testing by nurses using the BD FACSPresto at rural health care facilities showed high technical similarity to test results generated by laboratory technicians using the BD FACSPresto in a high functioning laboratory. The BD FACSPresto performed favorably in the laboratory setting compared to the conventional reference standard technologies; however, the lower sensitivities indicated that up to 20% of patients tested in the field in need of treatment would be missed. The BD FACSPresto is a technology that can allow for greater decentralization and wider access to CD4+ T cell testing and ART.