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 Problem False Positive Result (1227)

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 device's suspected false positive reactivity was detected as part of a scientific study.Single mdr related to each involved batch is submitted: lot 258005 mdr code 9610240-2021-00004; lot 258007 mdr code 9610240-2021-00005; lot 258010 mdr code 9610240-2021-00005; during a scientific study conducted in may-june 2020, (b)(6) was comparing the performance of four commercially available serology assays when they identified suspected false positive results with the diasorin device at a rate of about 1-2%.The study was focused on comparison of methods based on nucleocapsid vs spike protein and included about 1200 de-identified leftover specimen that were submitted for covid-19 serology testing (600 initial positive specimens by abbott, 600 negative specimes, no pre-covid).The study included diasorin, ortho and euroimmune.Overall agreement between the four assays was greater than 95%.Results were compared for all methods based on consensus positive and consensus negative: when each of the assays was compared to consensus results, all 4 assays ranged from an agreement of 96-99%.Diasorin device was suspected of being falsely positive because the results were discordant with the other three serology assays and the specimen had unexpected reactivity with an in-house inhibition assay.15 positive samples were identified by diasorin only (according to other methods, they were negative).6 of the 15 positive samples by diasorin included 6 reactive ones and, after retest, they resulted negative.Other 9 samples were repeatedly positive and were tested with a quest lab developed inhibition assay.Two aliquots of each sample were made: one incubated with saline, the other incubated with recombinant spike protein.All the remaining 9 positive samples showed 10% inhibition or less, therefore customer assumed they were false positive.The 1200 samples were tested on all assays over a period of days.Customer had no knowledge of how the samples were prepared and handled before they arrived at their laboratory.They received serum samples only and samples were not re-spun.Lot 358005 was used for the 600 negative samples study; lots 358005 and 358007 were used for the 600 chantilly positive samples study; lot 358010 was used for the inhibition runs.The customer also stated that the results were analyzed and, when the diasorin result was compared to the consensus result, negative agreement was 97.5% and positive agreement was 96.2%.The customer indicated that the diasorin assay met specifications and assay results were within ifu expected performance.Based on the information provided, the complaint was classified as confirmed due to the occurrence of the event.Based on data obtained in-house, 500 blood donor samples were tested obtaining the following results for the involved kits: kit lot 358005: 99.0%, kit lot 358007: 99.8%, kit lot 358010: 99.8%, ifu claim: 99.3% with a 95% ci of 98.6-99.6%.Kit lots met specifications.No clear root cause could be identified; probable causes are most likely to be instrument- or handling-related.Performance of the liaison sars-cov-2 s1/s2 igg kit was verified and confirmed to be coherent with the claimed one.Release batch sheet and nc database were reviewed without highlighting anomalies.

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 device's suspected false positive reactivity was detected as part of a scientific study.

• 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: 11989074
• MDR Text Key: 259224731
• Report Number: 9610240-2021-00006
• 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: 06/01/2021

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: 11/08/2020
• Device Catalogue Number: 311460
• Device Lot Number: 358010
• Was Device Available for Evaluation?: No
• Is the Reporter a Health Professional?: Yes
• Date Manufacturer Received: 07/03/2020
• Was Device Evaluated by Manufacturer?: Device Not Returned to Manufacturer
• Date Device Manufactured: 05/27/2020
• 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