Validation of an automated immunoglobulin G–only cytomegalovirus (CMV) antibody screening assay and an assessment of the risk of transfusion transmitted CMV from seronegative blood

Authors

  • Clive R. Seed,

    1. From the Australian Red Cross Blood Service, and the School of Surgery, University of Western Australia, Perth, Australia; the Australian Red Cross Blood Service, Adelaide, Australia; Abbott Diagnostics Division, Abbott Park, Illinois; the Department of Microbiology and Virology, University of Bologna, Bologna, Italy; and Dianalabs, Geneva, Switzerland.
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  • Lisa M. Piscitelli,

    1. From the Australian Red Cross Blood Service, and the School of Surgery, University of Western Australia, Perth, Australia; the Australian Red Cross Blood Service, Adelaide, Australia; Abbott Diagnostics Division, Abbott Park, Illinois; the Department of Microbiology and Virology, University of Bologna, Bologna, Italy; and Dianalabs, Geneva, Switzerland.
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  • Gregory T. Maine,

    1. From the Australian Red Cross Blood Service, and the School of Surgery, University of Western Australia, Perth, Australia; the Australian Red Cross Blood Service, Adelaide, Australia; Abbott Diagnostics Division, Abbott Park, Illinois; the Department of Microbiology and Virology, University of Bologna, Bologna, Italy; and Dianalabs, Geneva, Switzerland.
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  • Tiziana Lazzarotto,

    1. From the Australian Red Cross Blood Service, and the School of Surgery, University of Western Australia, Perth, Australia; the Australian Red Cross Blood Service, Adelaide, Australia; Abbott Diagnostics Division, Abbott Park, Illinois; the Department of Microbiology and Virology, University of Bologna, Bologna, Italy; and Dianalabs, Geneva, Switzerland.
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  • Kathleen Doherty,

    1. From the Australian Red Cross Blood Service, and the School of Surgery, University of Western Australia, Perth, Australia; the Australian Red Cross Blood Service, Adelaide, Australia; Abbott Diagnostics Division, Abbott Park, Illinois; the Department of Microbiology and Virology, University of Bologna, Bologna, Italy; and Dianalabs, Geneva, Switzerland.
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  • Reto Stricker,

    1. From the Australian Red Cross Blood Service, and the School of Surgery, University of Western Australia, Perth, Australia; the Australian Red Cross Blood Service, Adelaide, Australia; Abbott Diagnostics Division, Abbott Park, Illinois; the Department of Microbiology and Virology, University of Bologna, Bologna, Italy; and Dianalabs, Geneva, Switzerland.
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  • René Stricker,

    1. From the Australian Red Cross Blood Service, and the School of Surgery, University of Western Australia, Perth, Australia; the Australian Red Cross Blood Service, Adelaide, Australia; Abbott Diagnostics Division, Abbott Park, Illinois; the Department of Microbiology and Virology, University of Bologna, Bologna, Italy; and Dianalabs, Geneva, Switzerland.
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  • Beimar Iriarte,

    1. From the Australian Red Cross Blood Service, and the School of Surgery, University of Western Australia, Perth, Australia; the Australian Red Cross Blood Service, Adelaide, Australia; Abbott Diagnostics Division, Abbott Park, Illinois; the Department of Microbiology and Virology, University of Bologna, Bologna, Italy; and Dianalabs, Geneva, Switzerland.
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  • Chandu Patel

    1. From the Australian Red Cross Blood Service, and the School of Surgery, University of Western Australia, Perth, Australia; the Australian Red Cross Blood Service, Adelaide, Australia; Abbott Diagnostics Division, Abbott Park, Illinois; the Department of Microbiology and Virology, University of Bologna, Bologna, Italy; and Dianalabs, Geneva, Switzerland.
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Clive R. Seed, Australian Red Cross Blood Service, 290 Wellington Street, Perth, Western Australia 6000, Australia; e-mail: cseed@arcbs.redcross.org.au.

Abstract

BACKGROUND: Cytomegalovirus (CMV) antibody donor screening assays have predominantly included both immunoglobulin G (IgG) and immunoglobulin M (IgM) detection. However, since in the majority of cases both CMV IgG and IgM are detected concomitantly during early seroconversion, CMV assays based only on IgG are now widely applied for donor screening.

STUDY DESIGN AND METHODS: The performance of an automated microparticle CMV IgG assay (Abbott AxSYM CMV IgG microparticle enzyme immunoassay [MEIA]) was compared with an established total antibody blood screening assay (Abbott CMV Total AB EIA). Sensitivity and specificity were assessed using 5050 random blood donors and 13 seroconversion panels. A risk analysis was undertaken to estimate the residual risk of transfusion-transmitted CMV (TT-CMV) from presumptive seronegative blood components.

RESULTS: The EIA achieved marginally (but not significantly) better resolved sensitivity (100%) than the AxSYM IgG assay (99.93%). The AxSYM IgG resolved specificity (99.34%) was superior to the EIA (96.4%). This superiority was maintained (98.61%) when a modified cutoff was applied to the AxSYM IgG assay to achieve 100 percent resolved sensitivity. The seroconversion sensitivities of the EIA and the AxSYM IgG were equivalent, detecting the same bleed as positive in the majority of the seroconversion panels tested. The median TT-CMV residual risk estimate for the two assays was approximately 1 in 66,000 (range, 42,000-165,000).

CONCLUSION: The AxSYM IgG MEIA is suitable for blood donor screening and was optimized by applying a modified cutoff of 9 AU per mL. The modeling predicts that implementing the AxSYM IgG assay would not negatively impact the already very low risk of TT-CMV associated with seronegative blood components in Australia.

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