MAUDE Adverse Event Report: DIASORIN S.P.A. LIAISON SARS-COV-2 S1/S2 IGG; QUALITATIVE DETECTION OF IGG ANTIBODIES TO SARS-COV-2

Catalog Number 311460

Device Problems False Positive Result (1227); Non Reproducible Results (4029)

Patient Problem No Clinical Signs, Symptoms or Conditions (4582)

Event Type  malfunction  

Manufacturer Narrative

Diasorin (b)(4) received a complaint from a customer stating that discrepant results were obtained for eleven (11) patients that resulted positive on the liaison xl with the liaison sars-cov-2 s1/s2 igg assay.Single mdr related to each involved batch is submitted: lot 258005; lot 258008 mdr code 9610240-2021-00031.Seven of the eleven positive results were reported as negative with mayo assay.Data provided by customer showed 5 samples (labeled as sample 1, 2, 5, 6, 9) previously positive with kit lot 358005 and resulted as negative when repeated with lot 358008.In addition, 4 samples (labeled as sample 8, 11, 12, 14), resulted repeatedly as positive with both lots 358005 and 358008, but were graded as negative with mayo method (a method called edi, being run on dsx and measuring nucleocapsid).Based on patient history, for samples 11, 13, and 14, patients were ill or very sick in late 2019 and early 2020.The mayo test is measuring antibodies to nucleocapsid protein and the diasorin method is measuring antibodies to spike proteins: even if both nucleocapsid proteins and spike proteins should elicit an abundant antibody response in patients, different results between assays using different proteins and assay design may not be unexpected.Discordant samples were also sent to another laboratory to be tested with roche assay.Some isolated discordant results were obtained with the various methods: some with three-way agreement and others with differences between diasorin vs mayo, diasorin vs roche and roche vs mayo.In the study, the customer also observed some isolated lot-to-lot differences.Based on internal release testing, data showed that both lots 358005 and 358008 meet specifications.The lot testing was done with a different qc sample panel set, as the samples used in the release testing for lot 358005 (and earlier lots) were depleted.The internal testing included both negative and positive samples and several samples, at the lower end, were near the cut-off.All negative and positive qc samples resulted as expected and within specifications, but, as seen in customer study, some differences in au/ml were noted between the two lots tested.Results were reviewed with the customer medical director and the recommendation was to continue confirming diasorin positive results.Additionally, the customer planned to repeat samples with results of 3 au on either side of the cut-off value: no large discrepancies were detected with repeat analysis since opening the new lot.The complaint was classified as not confirmable.As reported in the ifu, the liaison sars-cov-2 s1/s2 igg assay and its clinical performance are based on clinical sensitivity defined by pcr positive; no comparison studies with other serological tests are available and differences with competitor assays may be expected and cannot be related to product deficiencies.The issue was considered related to specific tested samples, but no drift on performance was highlighted.

Event Description

In light of the covid-19 pandemic and the subsequent authorizations (euas) for sars-cov-2 diagnostics tests and per the conditions of the emergency use authorization, suspected false negatives, false positives and significant changes in expected performance characteristics will be reported under 21 cfr 803.The alleged false test results in this event have not caused patient injury or death; however, this event is being reported conservatively because if the alleged malfunction were to recur there is a non-remote potential for serious injury or death.Diasorin (b)(4) received a complaint from a customer stating that discrepant results were obtained for eleven patients that resulted positive with the liaison sars-cov-2 s1/s2 igg assay.

• Brand Name: LIAISON SARS-COV-2 S1/S2 IGG
• Type of Device: QUALITATIVE DETECTION OF IGG ANTIBODIES TO SARS-COV-2
• Manufacturer (Section D): DIASORIN S.P.A.; via crescentino snc; saluggia, vercelli 13040 ; IT 13040
• Manufacturer (Section G): DIASORIN S.P.A.; via crescentino snc; saluggia, vercelli 13040 ; IT 13040
• Manufacturer Contact: barbara belluati ; via crescentino snc; saluggia, vercelli 13040 ; IT 13040
• MDR Report Key: 11988973
• MDR Text Key: 259223732
• Report Number: 9610240-2021-00030
• Device Sequence Number: 1
• Product Code: QKO
• Combination Product (y/n): N
• Reporter Country Code: US
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: health professional
• Reporter Occupation: Other Health Care Professional
• Type of Report: Initial
• Report Date: 06/06/2021

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Date FDA Received: 06/13/2021
• Is this an Adverse Event Report?: No
• Is this a Product Problem Report?: Yes
• Device Operator: Health Professional
• Device Expiration Date: 10/11/2020
• Device Catalogue Number: 311460
• Device Lot Number: 358005
• Was Device Available for Evaluation?: No
• Is the Reporter a Health Professional?: Yes
• Date Manufacturer Received: 05/28/2020
• Was Device Evaluated by Manufacturer?: Device Not Returned to Manufacturer
• Date Device Manufactured: 04/29/2020
• Is the Device Single Use?: Yes
• Is This a Reprocessed and Reused Single-Use Device?: No
• Type of Device Usage: Initial
• Patient Sequence Number: 1