The complaint investigation for false negative architect 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.Return testing was not complete as patient samples were not available.Sensitivity testing was done using an in-house retained kit of lot 37306fn00, stored at the recommended storage conditions.All validity and acceptance criteria were met indicating that the lot is performing acceptably.Device history record review on lot 37306fn00 did not show any potential non-conformances or deviations.Labeling was reviewed and found to adequately address the issue under review.The customer observed a potential false negative sars-cov2 igg result for one leukemia patient with covid-19 when testing was performed with architect sars-cov-2 igg, lot 37306fn00, when compared to a positive result on the sars-cov-2 igg ii quant assay.The sars-cov-2 igg ii quant assay is designed to detect immunoglobulin class g (igg) antibodies, including neutralizing antibodies, to the receptor binding domain (rbd) of the s1 subunit of the spike protein, whereas the sars-cov-2 igg assay is designed to detect igg antibodies to the nucleocapsid protein of sars-cov-2.Based on current literature, long, q-x et al, ¿https://www.Nature.Com/articles/s41591-020-0897-1¿, igg levels may not appear until 7 to 10 days after infection.In addition, emerging literature on sars cov-2 serology indicates that antibody responses to the virus decline over time.In some cases, this transient response results in the decline of both igg and neutralizing antibody titers.It remains unknown for how long antibodies persist following infection and if the presence of antibodies is indicative of protective immunity, seow et al, ¿https://doi.Org/10.1101/2020.07.09.20148429¿, and ou et al, ¿https://doi.Org/10.1101/2020.05.22.20102525¿.The study, quan-xin long et al, ¿clinical and immunological assessment of asymptomatic sars-cov-2 infections¿, nature medicine, 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.Negative results do not rule out sars-cov-2 infection, particularly in those who have been in contact with the virus.Follow-up testing with a molecular diagnostic should be considered to rule out infection in these individuals.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.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.Based on the investigation architect sars-cov-2 igg reagent lot 37306fn00 is performing as intended, no systemic issue or deficiency was identified.
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