Evaluation of TruCount Absolute-Count Tubes for Determining CD4 and CD8 Cell Numbers in Human Immunodeficiency Virus-Positive Adults
- 1 May 2000
- journal article
- Published by American Society for Microbiology in Clinical and Diagnostic Laboratory Immunology
- Vol. 7 (3), 336-343
- https://doi.org/10.1128/cdli.7.3.336-343.2000
Abstract
A single-platform technology that uses an internal bead standard and three-color flow cytometry to determine CD4 and CD8 absolute counts was evaluated for reproducibility and agreement. Values obtained using TruCount absolute-count tubes were compared to those obtained using a two-color predicate methodology. Sixty specimens from human immunodeficiency virus type 1-infected donors were shipped to five laboratories. Each site also analyzed replicates of 14 human immunodeficiency virus type 1-infected local specimens at 6 h and again at 24 h. The interlaboratory variability was significantly less with TruCount (median difference in percent coefficient of variation [%CV] between the two methods was −8% and −3% for CD4 and CD8, respectively) than with the predicate method. Intralaboratory variability was smaller, with a median difference in %CV of −1% for both CD4 and CD8 with 6-h samples and −2% and −3% for CD4 and CD8, respectively, with 24-h samples. Use of TruCount for shipped samples resulted in a median CD4 count change of 7 cells (50th estimated percentile) when all laboratories and CD4 strata were combined. For on-site samples, the median CD4 count change was 10 CD4 cells for 6-h samples and 2 CD4 cells for 24-h samples. Individual site biases occurred in both directions and cancelled each other when the data were combined for all laboratories. Thus, the combined data showed a smaller change in median CD4 count than what may have occurred at an individual site. In summary, the use of TruCount decreased both the inter- and intralaboratory variability in determining absolute CD4 and CD8 counts.Keywords
This publication has 15 references indexed in Scilit:
- Automated cell count in flow cytometry: a valuable tool to assess CD4 absolute levels in peripheral blood.American Journal of Clinical Pathology, 1998
- Positive Effects of Combined Antiretroviral Therapy on CD4 + T Cell Homeostasis and Function in Advanced HIV DiseaseScience, 1997
- 1997 revised guidelines for performing CD4+ T-cell determinations in persons infected with human immunodeficiency virus (HIV). Centers for Disease Control and Prevention.1997
- Evaluation of alternative CD4 technologies for the enumeration of CD4 lymphocytesJournal of Immunological Methods, 1994
- A Parallel Evaluation of Four Automated Hematology AnalyzersAmerican Journal of Clinical Pathology, 1993
- Effect of Time, Temperature, and Anticoagulant on Flow Cytometry and Hematological ValuesAnnals of the New York Academy of Sciences, 1993
- Effect of type of haematology analyser on CD4 countThe Lancet, 1992
- The Prognostic Value of Cellular and Serologic Markers in Infection with Human Immunodeficiency Virus Type 1New England Journal of Medicine, 1990
- Precision and accuracy of absolute lymphocyte countsClinical Immunology and Immunopathology, 1989
- Decline in CD4+Cell Numbers Reflects Increase in HIV-1 ReplicationAIDS Research and Human Retroviruses, 1988