MAUDE Adverse Event Report: ROCHE DIAGNOSTICS COBAS C 303 ANALYTICAL UNIT; CLINICAL CHEMISTRY ANALYZER

Catalog Number	09793194001
Medical Device Problem Codes	High Test Results (2457); Non Reproducible Results (4029)
Health Effect - Clinical Code	No Clinical Signs, Symptoms or Conditions (4582)
Date of Event	02/05/2026
Type of Reportable Event	Malfunction
Event or Problem Description
There was an allegation of questionable potassium results from the cobas c 303 analytical unit.The initial result was 5.7 mmol/l.The repeat result was 3.8 mmol/l.A new sample was drawn from the patient, and the result was 3.8 mmol/l.The result of 3.8 mmol/l was believed to be correct.
Additional Manufacturer Narrative
The electrode lot number was fnd with an expiration date of 07-nov-2026.The field service engineer checked the analyzer and did not find a cause.He checked the sample probe, ise nozzles, electrode block, and syringes.He ran ise precision testing, which passed.The investigation is ongoing.
Additional Manufacturer Narrative
The investigation could not determine a specific root cause.The calibration and qc recovery were acceptable.The analyzer alarm trace contained no conspicuous events.The instrument performance was verified, and the issue appeared to be resolved.

• Brand Name: COBAS C 303 ANALYTICAL UNIT
• 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: 24470377
• Report Number: 1823260-2026-00723
• Device Sequence Number: 10262213
• Product Code: JJE
• UDI-Device Identifier: 07613336220153
• UDI-Public: 07613336220153
• Combination Product (Y/N): N
• Initial Reporter State: CO
• Initial Reporter Country: US
• PMA/510(K) Number: K220134
• 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,Followup
• Report Date (Section B): 03/20/2026

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: 09793194001
• Was Device Available for Evaluation?: Yes
• Is the Reporter a Health Professional?: Yes
• Type of Report(Section G): Initial
• Initial Date Received by Manufacturer: 02/09/2026
• Supplement Date Received by Manufacturer: 03/02/2026
• Initial Report FDA Received Date: 02/27/2026
• Supplement Report FDA Received Date: 03/20/2026
• 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