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

Catalog Number	04826876001
Medical Device Problem Code	Non Reproducible Results (4029)
Health Effect - Clinical Code	No Clinical Signs, Symptoms or Conditions (4582)
Date of Event	10/24/2025
Type of Reportable Event	Malfunction
Event or Problem Description
The initial reporter received questionable potassium and chloride electrode results from one patient sample tested on the cobas 4000 c311 stand alone system.Potassium the initial result from the analyzer is 9.19 mmol/l.The repeat result from a b 221 analyzer is 4.6 mmol/l.Chloride the initial result from the analyzer is 47.4 mmol/l.The repeat result from a b 221 analyzer is 105 mmol/l.
Additional Manufacturer Narrative
The electrode lot numbers and their expiration dates were requested but not provided.The investigation is ongoing.
Additional Manufacturer Narrative
The investigation included a review of the data set provided by the customer: the calibration, qc, and ion-selective electrode check results indicated that the analyzer was performing according to specifications.The field service engineer inspected the analyzer and resolved a pipetting issue, which was unrelated to the event.The investigation did not identify a product problem.The cause of the event could not be determined.The customer did not report any other issues.

• 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
• MDR Report Key: 23580726
• Report Number: 1823260-2025-04676
• Device Sequence Number: 18467758
• Product Code: JJE
• UDI-Device Identifier: 04015630925551
• UDI-Public: 04015630925551
• Combination Product (Y/N): N
• Initial Reporter Country: AR
• 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): 01/23/2026

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
• Was Device Available for Evaluation?: Yes
• Is the Reporter a Health Professional?: Yes
• Type of Report(Section G): Follow-Up
• Initial Date Received by Manufacturer: 10/24/2025
• Supplement Date Received by Manufacturer: 01/08/2026
• Initial Report FDA Received Date: 11/18/2025
• Supplement Report FDA Received Date: 01/23/2026
• 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