On 14sep2021 the customer reported non-reactive sars-cov-2 igg (1st is) (access sars-cov-2 igg (1st is) assay, part number c74339, lot number not provided) results were generated for two vaccinated patients on the customer's unicel dxi 800 access immuno analyzer (part number 973100 and serial number (b)(4)).¿ patient one: the non-reactive access sars-cov-2 igg 1st is results were 28.94 iu/ml on (b)(6) 2021 repeated at 22.50 iu/ml on (b)(6) 2021.The access results were discordant with the siemens result of: 3.88 unit/ml on (b)(6) 2021 (cut-off: 1).¿ patient two: the non-reactive access sars-cov-2 igg 1st is results were 27.15 iu/ml on (b)(6) 2021 repeated at 29.76 iu/ml on (b)(6) 2021.The access results were discordant with the abbott result of 788.2 au/ml on (b)(6) 2021 (cut-off: 50) and the siemens result of 6.72 unit/ml on (b)(6) 2021 (cut-off: 1).The patients were vaccinated six months before.There was no report of an injury or illness to the patient attributable to the output from the device in this event.No hardware errors or issues with other assays were reported in conjunction with this event.No calibration or system check data was provided.Per customer¿s verbal report, quality control (qc) has been passing within the laboratory¿s established ranges.There were no issues with sample integrity reported by the customer.Sample information such as sample collection tube used, centrifugation time and speed, storage or handling was not provided by the customer.Two (2) medwatch reports will be generated to address the two different dates of initial questioned results from the two patients: medwatch number ¿2122870-2021-00161¿ will address patient one; medwatch number ¿2122870-2021-00162¿ will address patient two.
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(b)(6).The customer did not supply patient demographics such as age, date of birth, weight, ethnicity or race.No lot number was provided, no udi, no device manufacture date could be provided.The access sars-cov-2 igg 1st is reagent was not returned for evaluation.No hardware errors or other assay issues were reported in conjunction with this event.There have not been any studies yet comparing the access sars-cov-2-igg (1 st is) assay to any other manufacturers.The concentration of sars-cov-2 igg in a given specimen determined with assays from different manufacturers can vary due to differences in assay methods, diversity of antibodies and reagent specificity.Results obtained with the access assay may not be used interchangeably with values obtained with different manufacturers¿ test methods.Per the who study, ¿establishment of the who international standard reference panel for anti-sars-cov-2 antibody¿, mattiuzzo et al., variability of quantitative results with the who 1st is is evident manufacturer to manufacturer and method to method.Variation amongst quantitative results of serology assays are expected even when traceable to the same who international standard.Some factors which may contribute to variability of inter-manufacturer results are affinity of the antibodies in positive samples, assay format, and clinical decision points for the assay.Although variability amongst quantitative results is expected, qualitative result should be in alignment with the results of manufacturers who also have a who traceable igg assay.There is no international consensus determining the protective antibody response for sars-cov-2.The access assay is not labelled for vaccine response detection.The performance of our serology assays has not been established in individuals that have received a covid-19 vaccine.Depending upon the vaccine administered, the antibodies generated may be different and therefore the test result may differ depending upon the specific antibody being detected by the assay in use in the laboratory.A meeting was held with medical science department who discussed discrepancies between methods with the customer.In conclusion, a cause for this event could not be determined with the information supplied.The access assay is not labelled for vaccine response detection.There is no evidence to reasonably suggest that a malfunction occurred in conjunction with this event.
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