The customer observed false negative sars-cov-2 igg results for one patient, who had a positive pcr test on (b)(6) 2020, when compared to the sars-cov-2 igm results on an alinity i analyzer.The following data was provided (sars-cov-2 igg reference range is <1.4 index (s/c) is negative; sars-cov-2 igm reference range is >/=1.00 index (s/c) is positive): sample id (b)(6) igg result, on (b)(6) 2020, was 0.80 index (s/c); igm result was 11.26 index (s/c).Sample id (b)(6) igg result, on (b)(6) 2020, was 0.63 index (s/c); igm result was 8.71 index (s/c).Sample id (b)(6) igg result, on (b)(6) 2020, was 0.50 index (s/c); igm result was 5.89 index (s/c).Igg result, on (b)(6) 2020, was 0.51 index (s/c); igm result was 5.51 index (s/c).Igg result, on (b)(6) 2020, was 0.47 index (s/c); igm result was 4.51 index (s/c).Sample id (b)(6) igg result, on (b)(6) 2020, was 0.33 index (s/c); igm result was 3.77 index (s/c).Igg result, on (b)(6) 2020, was 0.34 index (s/c); igm result was 2.67 index (s/c).Igg result, on (b)(6) 2020, was 0.33 index (s/c); igm result was 2.95 index (s/c).Sample id (b)(6) igg result, on (b)(6) 2021, was 0.27 index (s/c); igm result was 2.11 index (s/c).There was no impact to patient management reported.
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(b)(4).Was this device serviced by a third party? no.The complaint investigation for false negative alinity sars-cov-2 igg results included a search for similar complaints, the review of complaint text, trending data, labeling, scientific literature, and device history records.Sensitivity and specificity testing was done using an in-house retained kit of lots 22469fn00 and 18512fn00, stored at the recommended storage conditions.Specificity testing was done using an in-house retained kit of lot 23478fn00, stored at the recommended storage conditions.All validity and acceptance criteria were met indicating that the lots are performing acceptably.Device history record review on the lot numbers did not show any potential non-conformances or deviations.Labeling was reviewed and found to adequately address the issue under review.The customer observed false negative sars-cov-2 igg results for one patient was performed using alinity sars-cov-2 igg reagent lots, 23478fn00, 22469fn00 and 18512fn00 compared to positive results with the sars-cov-2 igm assay.Testing was performed for the returned patient sample using the 06r91 igm assay, the 06r90 igg assay, and the 06s61 igg ii quant assay.Negative igg results were obtained for the sample which aligned with the customers observation.The return sample (id (b)(6)) was reactive on the igg ii quant and igm assays but negative on the igg assay indicating a higher reactivity to spike with possible seroreversion due to decreasing nucleocapsid igg and decreasing igm response.In this case, the patient had a positive rt-pcr result, but no specific patient clinical history was provided.According to the ¿report from the american society for microbiology covid-19 international summit, 23 march 2020: value of diagnostic testing for sars-cov-2/covid-19.Mbio 11:e00722-20¿, patel r, et al, it is unknown for certain whether individuals infected with sars¿cov-2 who subsequently recover will be protected, either fully or partially, from future infection with sars¿cov-2 or how long protective immunity may last.The study ¿clinical and immunological assessment of asymptomatic sars-cov-2 infections, nature medicine¿, quan-xin long, et al, showed that antibodies declined in both asymptomatic and symptomatic covid-19 patients during the early convalescence phase.It was observed that igg levels and neutralizing antibodies in a high proportion of individuals who recovered from sars-cov-2 infection start to decrease within 2-3 months after infection.To assess the clinical performance of the assay, a study was performed using 122 serum and plasma specimens collected at different times from 31 subjects who tested positive for sars-cov-2 by a polymerase chain reaction (pcr) method and who also presented with covid-19 symptoms.The positive percent agreement (ppa) at >/=14 days post-symptom onset is 100.00% (95% ci: 95.89, 100.00).Five specimens from 1 immunocompromised patient were excluded from the study.When the results from these specimens were included, the ppa at >/=14 days post-symptom onset was 96.77% (95% ci: 90.86, 99.33).This study was based on a hospitalized/symptomatic population.Differences in antibody responses between populations, based on more severe versus less severe illness, are consistent with published reports, zhao j et al.2020.Review of the manuscript ¿performance characteristics of the abbott architect sars-cov-2 igg assay and seroprevalence in boise, idaho¿, bryan et al.2020, showed sensitivity data consistent with product labeling.125 patients who tested rt-pcr positive for sars-cov-2 for which 689 excess serum specimens were available was tested and it was found that sensitivity reached 100% at day 17 after symptom onset and day 13 after pcr positivity.Per the limitations of the procedure section of the package insert, alinity sars-cov-2 igg results should be used in conjunction with other data; e.G., symptoms, results of other tests, and clinical impressions.Results from antibody testing should not be used as the sole basis to diagnose or exclude sars-cov-2 infection or to inform infection status.Negative results do not rule out sars-cov-2 infection, particularly in those who have been in contact with the virus.Based on the investigation, alinity sars-cov-2 igg reagent, lot numbers 23478fn00, 22469fn00 and 18512fn00, are performing as intended, no systemic issue or deficiency of the reagent was identified.
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