MAUDE Adverse Event Report: Roche Diagnostics cobas 4000 c311 stand alone system; CLINICAL CHEMISTRY ANALYZER

Catalog Number	04826876001
Medical Device Problem Code	High Test Results (2457)
Health Effect - Clinical Code	No Clinical Signs, Symptoms or Conditions (4582)
Date of Event	08/02/2026
Type of Reportable Event	Malfunction
Event or Problem Description
There was an allegation of questionable magnesium gen.2 results for 1 patient sample on a cobas 4000 c311 stand alone system.The initial result was 3.06 mg/dl with flag.The repeat result was 1.69 mg/dl.The repeat result was deemed correct.No questionable results were reported outside of the laboratory.
Additional Manufacturer Narrative
The analyzer serial number is (b)(6).The alarm trace showed water reservoir too low, liquid level sensor in vacuum tank and liquid in vacuum tank alarms.It was found that the customer centrifuges samples at 5500 rpm for 5 minutes, which may be too forceful and too short of a time.The field service engineer (fse) found that the water tank dirty and cleaned and decontaminated it, and also found dried droplets on the surface around the reagent probe wash station.The fse performed a cell blank and a hardware check and cleaned and decontaminated the sample and reagent probes.The investigation is ongoing.

• 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 -045
• 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--045
• MDR Report Key: 50480768
• Report Number: 1823260-2026-03527
• Device Sequence Number: 21383439
• Product Code: JJE
• UDI-Device Identifier: 04015630925551
• UDI-Public: 04015630925551
• Combination Product (Y/N): N
• Initial Reporter Country: US
• PMA/510(K) Number: K060373
• 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,Followup
• Report Date (Section B): 09/30/2026

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: 91699201
• Was Device Available for Evaluation?: Yes
• Is the Reporter a Health Professional?: No
• Initial Date Received by Manufacturer: 08/03/2026
• Supplement Date Received by Manufacturer: 09/07/2026
• Initial Report FDA Received Date: 08/27/2026
• Supplement Report FDA Received Date: 09/30/2026
• 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