MAUDE Adverse Event Report: ROCHE DIAGNOSTICS COBAS 4000 C311 STAND ALONE SYSTEM; CLINICAL CHEMISTRY ANALYZER

Catalog Number	04826876001
Medical Device Problem Codes	Low Test Results (2458); Non Reproducible Results (4029)
Health Effect - Clinical Code	No Clinical Signs, Symptoms or Conditions (4582)
Date of Event	12/31/2025
Type of Reportable Event	Malfunction
Additional Manufacturer Narrative
The serial number of the c311 analyzer is (b)(6).The investigation is ongoing.
Event or Problem Description
The initial reporter stated they received discrepant results for one patient sample tested with tina-quant hemoglobin a1c gen.3 - hemolysate and whole blood application on a cobas 4000 c311 stand alone system.The sample initially resulted in an hba1c value of 4.8 %.When tested on an unknown point of care device, the result was 5.3 %.
Additional Manufacturer Narrative
The data suggest that the reagent itself is likely not the primary cause, as the issue only manifests after two weeks of on-board stability.The discrepancy in patient results (0.5% absolute difference) confirms a negative bias consistent with the qc drift.A gradual decline in qc over time is indicative of buildup in the cuvettes.The field service engineer replaced the reagent probe, adjusted fluidic components, adjusted the water level and gear pump, and cleaned the water tank.The investigation determined the service actions resolved the issue.Medwatch fields d1, d2, d4, g1, and g4 have been updated.

• Brand Name: COBAS 4000 C311 STAND ALONE SYSTEM
• Common Device Name: CLINICAL CHEMISTRY ANALYZER
• Manufacturer (Section D): ROCHE DIAGNOSTICS; 9115 hague road; indianapolis IN 46250 0457
• Manufacturer (Section G): HITACHI HIGH TECH CORP.; 882 ichige hitachinaka; ibaraki 312-8 504; JA 312-8504
• Manufacturer Contact: natalie catton ; 9115 hague road; indianapolis, IN 46250-0457
• MDR Report Key: 24108375
• Report Number: 1823260-2026-00201
• Device Sequence Number: 17599329
• Product Code: JJE
• UDI-Device Identifier: 04015630925551
• UDI-Public: 04015630925551
• Combination Product (Y/N): N
• Initial Reporter Country: SA
• PMA/510(K) Number: K060373
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Serviced by Third Party (Y/N): Unknown
• Reporter Type: Manufacturer
• Report Source: Foreign,Health Professional,User Facility
• Initial Reporter Occupation: Other Health Care Professional
• Type of Report: Initial,Followup
• Report Date (Section B): 04/27/2026

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 Catalogue Number: 04826876001
• Device Lot Number: 887721
• Was Device Available for Evaluation?: Yes
• Is the Reporter a Health Professional?: Yes
• Type of Report(Section G): Initial
• Initial Date Received by Manufacturer: 12/31/2025
• Supplement Date Received by Manufacturer: 04/07/2026
• Initial Report FDA Received Date: 01/19/2026
• Supplement Report FDA Received Date: 04/27/2026
• 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