MAUDE Adverse Event Report: SIEMENS HEALTHCARE DIAGNOSTICS INC. ATELLICA IM TOXOPLASMA G (TOXO G); TOXOPLASMA GONDII IMMUNOASSAY

Model Number N/A

Device Problem False Positive Result (1227)

Patient Problem No Known Impact Or Consequence To Patient (2692)

Event Date 05/05/2020

Event Type  malfunction  

Manufacturer Narrative

The affected patient sample has been requested for additional testing by the manufacturer.Siemens healthcare diagnostics is investigating.The instruction for use (ifu) states in the interpretation of results section: "results of this assay should always be interpreted in conjunction with the patient's medical history, clinical presentation, and other findings." the instruction for use (ifu) states in the limitations section: "specimens collected in the early stages of infection may have igg levels that are classified as negative.In geographic regions that have an apparent low prevalence of toxoplasma igg in asymptomatic populations, the positive predictive value of any assay is reduced due to the increased possibility that a positive result is actually falsely positive.As with all in vitro diagnostic assays, each laboratory should determine its own reference range(s) for the diagnostic evaluation of patient results.".

Event Description

A discordant positive result was observed for a single patient using the toxoplasma igg (toxo g) assay, on the atellica im 1600 analyzer.Result was expected to be negative (<6.4 iu/ml).The same patient serum sample produced a negative result when tested using an alternate testing method.A previous serum from the same patient, previously measured at <6.4iu/ml (negative) with reagent lot 258, was reanalyzed and detected as positive (14 iu/ml) with reagent lot 260.Patient treatment was not prescribed or altered.There was no report of adverse health consequences as a result of the discordant toxo g result(s).

Manufacturer Narrative

Siemens filed the initial mdr on 05/27/2020 reporting a presumed false-positive toxo igg result.Additional information received 05/29/2020: a sample from the affected patient was retested at an alternate site using an alternate method and the result was negative for toxo igg.The customer also noted that there was a total of 3 different samples from 3 different patients that showed the same discrepancy.There are no reports of impact to the patients as the results were not provided to the physicians.No further details were provided.Siemens healthcare diagnostics continues to investigate.

Manufacturer Narrative

Siemens filed initial mdr 1219913-2020-00128 on 27-may-2020 to report a false-reactive atellica im toxoplasma igg (toxo g) result; mdr 1219913-2020-00128 supplemental report 1 was filed 23-jun-2020 to report updated information.Additional information, 06-nov-2020: siemens has concluded the investigation.The customer reported a false reactive toxoplasma igg (toxo g) patient result when using reagent lot 260.The result was discordant relative to patient history and results obtained for the same sample when tested by alternate methods.An earlier sample from the same patient which had produced a negative result with reagent lot 258 produced a positive result when re-tested using lot 260.The customer declined to provide calibration, quality control, or sample-handling information, and did not provide the total number of negative samples tested in reagent lot 260, so site-specific performance could not be evaluated.Siemens performed an internal study that included toxo g reagent lots 258, 260 and 262, fifty (50) normal patient samples from siemens and fifty (50) patient samples from france.[patient samples from france for the internal study were purchased by siemens from an approved supplier and french acquisition company (inospecimens niobank).] all samples were tested in replicates of 3 (n=3).The final interpretation was the same for all patient samples across all reagent lots, with the exception of 1 siemens sample.Which was near the cutoff of 10 iu/ml.The recovery for this sample was within acceptable precision at that concentration level.Based on the available information, atellica im toxoplasma igg lot 260 is performing as intended and a product performance issue has not been identified.The customer is operational.The assay is performing within specifications.No further evaluation of the device is required.In section h6, the investigation finding and investigation conclusion codes were updated.

• Brand Name: ATELLICA IM TOXOPLASMA G (TOXO G)
• Type of Device: TOXOPLASMA GONDII IMMUNOASSAY
• Manufacturer (Section D): SIEMENS HEALTHCARE DIAGNOSTICS INC.; 511 benedict ave.; tarrytown, ny
• MDR Report Key: 10093028
• MDR Text Key: 229528605
• Report Number: 1219913-2020-00128
• Device Sequence Number: 1
• Product Code: LGD
• UDI-Device Identifier: 00630414600123
• UDI-Public: 00630414600123
• Combination Product (y/n): N
• PMA/PMN Number: K012183
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: foreign,health professional,u
• Type of Report: Initial,Followup,Followup
• Report Date: 11/13/2020

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Is this an Adverse Event Report?: No
• Is this a Product Problem Report?: Yes
• Device Operator: Health Professional
• Device Expiration Date: 02/14/2021
• Device Model Number: N/A
• Device Catalogue Number: 10995699
• Device Lot Number: 260
• Was Device Available for Evaluation?: No
• Initial Date Manufacturer Received: 05/11/2020
• Initial Date FDA Received: 05/27/2020
• Supplement Dates Manufacturer Received: 05/29/2020; 11/06/2020
• Supplement Dates FDA Received: 06/23/2020; 11/13/2020
• Is This a Reprocessed and Reused Single-Use Device?: No
• Patient Sequence Number: 1