MAUDE Adverse Event Report: ROCHE DIAGNOSTICS COBAS U 601 URINE ANALYZER; AUTOMATED URINE ANALYZER

Catalog Number	06390498001
Medical Device Problem Codes	Incorrect, Inadequate or Imprecise Result or Readings (1535); Intermittent Program or Algorithm Execution (4035)
Health Effect - Clinical Code	No Clinical Signs, Symptoms or Conditions (4582)
Date of Event	01/14/2026
Type of Reportable Event	Malfunction
Event or Problem Description
We received an allegation of a sample mismatch for eighty (80) urine patient samples tested on the cobas u 601 urine analyzer.The reporter stated that some patient samples had an erythrocyte result of "+3" or "+4", but no erythrocytes were detected in the microscopic reading.They suspect a sample mismatch, as the sample in one rack position was waiting for the sample rack in another position of the following rack to be completed before the result was reported.
Additional Manufacturer Narrative
The sw cobas 6500 software version is v2.4.0.The customer stated that there may have been an alarm of low water supply, and they opened the cover during the operation.The investigation is ongoing.
Additional Manufacturer Narrative
The investigation identified a software defect in the cassette-empty handling logic introduced in software version 2.4.0.Due to asynchronous system timing, the cassette-empty condition may be detected while the last strip of a run is already in the pipetting/measurement process.In this scenario, the software may prematurely interrupt the final measurement before it is fully finalized and before the internal memory queue is cleared.As a result, the incomplete measurement remains in the system memory queue, which can lead to a misalignment between processed samples and reported strip results.The behavior can only occur under a rare combination of specific timing and workflow conditions when the strip cassette becomes empty during processing of the final sample of a run.The issue can only occur if all of the following conditions are met simultaneously: the number of remaining strips exactly matches the number of samples left in the current run.The final available strip is already in active pipetting/measurement for the last sample.The cassette-empty condition is detected during this measurement due to system timing.The operator resumes operation after cassette replacement without performing a system initialization.

• Brand Name: COBAS U 601 URINE ANALYZER
• Common Device Name: AUTOMATED URINE ANALYZER
• 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: 24295655
• Report Number: 1823260-2026-00442
• Device Sequence Number: 15809145
• Product Code: KQO
• UDI-Device Identifier: 04015630932443
• UDI-Public: 04015630932443
• Combination Product (Y/N): N
• Initial Reporter Country: CA
• PMA/510(K) Number: K183432
• 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): 03/23/2026

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: 06390498001
• Was Device Available for Evaluation?: Yes
• Is the Reporter a Health Professional?: Yes
• Type of Report(Section G): Initial
• Initial Date Received by Manufacturer: 01/15/2026
• Supplement Date Received by Manufacturer: 03/06/2026
• Initial Report FDA Received Date: 02/09/2026
• Supplement Report FDA Received Date: 03/23/2026
• 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