MAUDE Adverse Event Report: ROCHE DIAGNOSTICS ELECSYS HBSAG II; TEST, HEPATITIS B (B CORE, BE ANTIGEN, BE ANTIBODY, B CORE IGM)

Catalog Number	08814856160
Medical Device Problem Code	False Positive Result (1227)
Health Effect - Clinical Code	No Clinical Signs, Symptoms or Conditions (4582)
Date of Event	10/19/2021
Type of Reportable Event	Malfunction
Event or Problem Description
The initial reporter alleged high patient recovery and false-positive results with the hbsag g2 elecsys cobas e 100 v2 assay on the cobas e411 disk.The first instance involved a patient sample tested on (b)(6) 2021.The initial result was 1.92 (reactive).A first rerun on the primary tube yielded 0.308 (non-reactive), and a second rerun from a hitachi cup yielded 0.310 (non-reactive).The second instance involved another patient sample drawn and tested on (b)(6) 2021.The initial result was 1.24 (reactive).A first rerun on the primary tube yielded 0.355 (non-reactive), and a second rerun yielded 0.332 (non-reactive).
Additional Manufacturer Narrative
The reported event occurred on a cobas e411 analyzer (serial number: (b)(6).The investigation determined that the issue was resolved by replacing the hbsag ii reagent pack and a block within the analyzer.The customer reported no further issues after switching to a new lot of the hbsag ii assay and using a replacement product provided for troubleshooting.The investigation did not identify a product performance issue with the hbsag ii assay itself.The device remains in operation at the customer site, and the case has been closed.A definitive root cause for the initial false-positive results could not be determined based on the available information.

• Brand Name: ELECSYS HBSAG II
• Common Device Name: TEST, HEPATITIS B (B CORE, BE ANTIGEN, BE ANTIBODY, B CORE IGM)
• Manufacturer (Section D): ROCHE DIAGNOSTICS; 9115 hague road; indianapolis IN 46250 0457
• Manufacturer (Section G): ROCHE DIAGNOSTICS GMBH; sandhofer strasse 116; mannheim (baden-wurttemberg) 68305 ; GM 68305
• Manufacturer Contact: natalie catton ; 9115 hague road; indianapolis, IN 46250
• MDR Report Key: 23058000
• Report Number: 1823260-2025-02890
• Device Sequence Number: 18471779
• Product Code: LOM
• UDI-Device Identifier: 07613336198285
• UDI-Public: 07613336198285
• Combination Product (Y/N): N
• Initial Reporter State: ME
• Initial Reporter Country: US
• PMA/510(K) Number: P160019
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Serviced by Third Party (Y/N): Unknown
• Reporter Type: Manufacturer
• Report Source: Health Professional,User Facility
• Initial Reporter Occupation: Other Health Care Professional
• Type of Report: Initial
• Report Date (Section B): 09/15/2025

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
• Operator of Device: Health Professional
• Device Expiration Date: 10/31/2021
• Device Catalogue Number: 08814856160
• Device Lot Number: 52602101
• Was Device Available for Evaluation?: Yes
• Is the Reporter a Health Professional?: Yes
• Type of Report(Section G): Initial
• Initial Date Received by Manufacturer: 10/20/2021
• Initial Report FDA Received Date: 09/15/2025
• Was Device Evaluated by Manufacturer? (Y/N): Yes
• Is the Device Labeled for Single Use? (Y/N): No
• Is This a Single-Use Device that was Reprocessed and Reused on a Patient? (Y/N): No
• Patient Sequence Number: 1
• Patient Sex: Unknown