A reliable and inexpensive EasyCD4 assay for monitoring HIV-infected individuals in resource-limited settings

Pachamuthu Balakrishnan, Suniti Solomon, Janardhanan Mohanankrishnan, Anitha J Cecelia, Nagalingeswaran Kumarasamy, Kailapuri G Murugavel, Bhavani Venkatakrishnan, Sunil S Solomon, Suzanne Mary Crowe, Aylur K Ganesh, Sadras P Thyagarajan, Timothy Flanigan, Kenneth H Mayer

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21 Citations (Scopus)


Serial measurements of absolute CD4+ T-lymphocyte counts are required to initiate and gauge response to therapy and monitor disease progression. Hence, there is an urgent need to evaluate the accuracy and validity of low-cost CD4+ T-cell count assays. Tripotassium EDTA blood specimens from HIV-infected individuals were studied using a novel flow cytometric assay (EasyCD4 assay; Guava Technologies, Hayward, CA) in comparison with standard flow cytometry (FACSCount; Becton Dickinson Immunocytometry Systems, San Jose, CA). The sensitivity, specificity value by EasyCD4 assay in enumerating absolute CD4+ T-cell counts of less than 200 cells/microL were 95 and 100 , respectively. Bland-Altman analysis showed close agreement, with the EasyCD4 assay yielding CD4+ T-cell counts a mean difference of -26 cells/microL (95 confidence interval, -96 to 44 cells/microL) higher than by flow cytometry. Our data suggest that EasyCD4 assay could be a useful alternative assay to conventional flow cytometry, may be appropriate for use in resource-limited settings.
Original languageEnglish
Pages (from-to)23 - 26
Number of pages4
Issue number1
Publication statusPublished - 2006
Externally publishedYes

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