On (b)(6) 2023, a representative for kuwait central blood bank in kuwait reported discordant hbv results between different testing methods for a serum sample (k55012303447100) used to screen a plasma donation.The ultrio elite screening assay (ue) and hiv, hcv, and hbv discriminatory assays (dhiv, dhcv, and dhbv, respectively) used ultrio elite master lot (ml) 704982.Testing results are as follows: (b)(6) 2023: anti-hbc positive.(b)(6) 2023: hbsag nonreactive.(b)(6) 2023: roche cobas mpx hbv reactive.(b)(6) 2023: ue nonreactive s/co 0.08.(b)(6) 2023: dhbv nonreactive s/co 0.00.(b)(6) 2023: ue dhiv nonreactive s/co 0.09.0.07.(b)(6) 2023: ue dhcv nonreactive s/co 0.00.The donation was blocked from use based on the roche reactive result.The ultrio elite assay and discriminatory assays were used as confirmation of the roche result.Grifols requested return of the remaining sample volumes to grifols san diego for investigational hbv quantitative testing but the customer was unable to return the samples.The root cause of the nonreactive ultrio elite result could not be determined.Although the nonreactive results could be due to the sample hbv concentration being at or below the ue hbv lod, this could not be confirmed though investigational hbv quantitative testing.Review of the design history data and a previous events search in the grifols complaint system indicate that the assay is working as designed.The customer shared that due to limited ue supply on hand, they were using roche as the test of record.Serum samples in question were tested the day after collection in roche and serology tests.Reactive samples were then frozen and tested in ue and discriminatory assays at a later date for confirmation of the roche result.Thawed samples were not homogenized before ultrio elite and discriminatory testing, and the same tube was used for all testing.Usage of the ultrio elite assay as a confirmatory test rather than a screening test is not part of the intended use of the assay.In addition, not adhering to the sample handling instructions in the package insert (lack of homogenization after thaw) may affect results.This testing methodology may introduce bias against the ultrio elite assay, leading to an excessive number of potential false negative results requiring confirmation by quantitation.The customer reported four other occurrences of the same issue (discordant ue and roche hbv results) that grifols reported as mdrs (listed below).In each case, the customer was using the assay outside the package insert instructions for intended use and specimen handling and was unable to return sample for quantitation.1.Initial mdr filed 14apr2023, follow-up filed 25may2023: 2032600-2023-00004-initial and 2032600-2023-00004-final.2.Initial mdr filed 31may2023: 2032600-2023-00006-initial.3.Initial mdr filed 19jun2023: 2032600-2023-00007-initial.4.Initial mdr filed 19jun2023: 2032600-2023-00008-initial.This report is final and no additional information is expected.
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