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

Catalog Number	08741034190
Medical Device Problem Code	False Negative Result (1225)
Health Effect - Clinical Code	No Clinical Signs, Symptoms or Conditions (4582)
Date of Event	09/18/2025
Type of Reportable Event	Malfunction
Additional Manufacturer Narrative
The cobas e 801 analytical unit serial number is (b)(6).The investigation is ongoing.
Event or Problem Description
There was an allegation of a questionable false negative elecsys hbsag ii auto confirm result from the cobas e 801 analytical unit for one patient.The elecsys hbsag ii auto confirm assay has embedded applications within it.The cnhbsag2 is an embedded application that has a reaction with the control pretreatment in the elecsys hbsag ii auto confirm assay.The cfhbsag2 is an embedded application that has a reaction with confirmatory pretreatment in the elecsys hbsag ii auto confirm assay.The initial hbsag result was 37.3 coi (reactive), with a repeat result of 37.4 coi (reactive).Confirmatory testing was completed with the following results: a cfhbsag2 result of 51.8 coi (reactive).A cnhbsag2 result of 55.0 coi (reactive).The hbsag ii auto confirm result was 94.3% (non-reactive).The hbs antigen was positive with the vidas method.Confirmatory testing was not completed with the vidas method.The hbv viral load was measured and was highly positive (>9 log).Another sample on (b)(6) 2025 gave an hbsag quantitative result of 459507 iu/ml.A sample collected from the same blood draw, tested on (b)(6) 2025, tested for hbsag with a dilution of 1:1000, had a result of 2510 coi (reactive).Confirmatory testing was completed with a dilution of 1:50, with the following results: a cfhbsag2 result of 0.472 coi (non-reactive).A cnhbsag2 result of 258 coi (reactive).The hbsag ii auto confirm result was 0.183% (reactive).On (b)(6) 2025, the initial sample was run again with the following results: a cfhbsag2 result of 228 coi (reactive) with a dilution of 1:50.A cnhbsag2 result of 2375 coi (reactive) with a dilution of 1:50.The hbsag ii auto confirm result was 9.61% (reactive).

• Brand Name: ELECSYS HBSAG II AUTO CONFIRM
• Common Device Name: HEPATITIS B (B CORE, BE ANTIGEN, BE ANTIBODY, B CORE IGM) TEST
• 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: 23302780
• Report Number: 1823260-2025-04203
• Device Sequence Number: 15934303
• Product Code: LOM
• UDI-Device Identifier: 07613336172902
• UDI-Public: 07613336172902
• Combination Product (Y/N): N
• Initial Reporter Country: FR
• PMA/510(K) Number: P160019/S014
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Serviced by Third Party (Y/N): N
• Reporter Type: Manufacturer
• Report Source: Foreign,Health Professional,User Facility
• Initial Reporter Occupation: Other Health Care Professional
• Type of Report: Initial
• Report Date (Section B): 10/15/2025

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: 01/31/2026
• Device Catalogue Number: 08741034190
• Device Lot Number: 79832501
• Was Device Available for Evaluation?: Yes
• Is the Reporter a Health Professional?: Yes
• Type of Report(Section G): Initial
• Initial Date Received by Manufacturer: 09/22/2025
• Initial Report FDA Received Date: 10/15/2025
• 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