MAUDE Adverse Event Report: ROCHE DIAGNOSTICS URISYS 1100 URINE ANALYZER; AUTOMATED URINE ANALYZER

Catalog Number	03617556001
Medical Device Problem Code	False Negative Result (1225)
Health Effect - Clinical Code	No Clinical Signs, Symptoms or Conditions (4582)
Date of Event	05/20/2025
Type of Reportable Event	Malfunction
Event or Problem Description
There was an allegation of questionable negative nitrite, leukocyte, and erythrocyte results for multiple urine patient samples tested with the chemstrip 10 md urine test strips on the urisys 1100 urine analyzer.One example of discrepant results for a patient with symptoms of urinary tract infection was provided: the analyzer results were negative.The customer's visual read of the results was positive (the customer was unable to specify if the results were for nitrites, leukocytes, or erythrocytes.) the customer stated that the test strip pads looked positive before they were placed on the meter, prompting the visual read of the test strip results.The results from the customer's visual read were deemed correct.
Additional Manufacturer Narrative
The chemstrip 10 md urine test strips lot number and expiration date were not provided.The customer reported that qc and calibration were passing.The investigation is ongoing.
Additional Manufacturer Narrative
All released chemstrip 10 md urine test strips lots underwent qc tests and were released without restrictions.Product labeling states: "limitations - interference leukocytes: false-negative readings may be produced if the urine specimen contains high concentrations of calcium chloride.High ph values caused by urinary tract infections and a lowered specific gravity might lead to false-positive readings in rare cases.The drugs cephalexin and gentamicin have been found to interfere with this test.In addition, nitrofurantoin colors the urine and this effect interferes with visual interpretation of the test strip.High levels of albumin (> 500 mg/dl) in the urine and urinary glucose excretion in excess of 1 g/dl may interfere with the test results." "nitrite: false-negative readings may be produced if the urine specimen contains high concentrations of creatinine and urobilinogen.If the urine specimen has a pronounced intrinsic color (for example, due to the presence of bilirubin, urobilinogen or erythrocytes), the reaction color may be intensified due to an additive effect.Large amounts of ascorbic acid (see under glucose) decrease the sensitivity of the test." "blood/hemoglobin: urine specimens that contain large amounts of beta-hydroxybutyrate may lead to false-negative results.False-negative readings are obtained when formalin is used to preserve the urine or on medications with nitrofurantoin, quinidines, acetaminophen, amoxicillin, furosemide, gabapentin and ibuprofen.This test has not been found to be affected by the ingestion of reasonable quantities of ascorbic acid (up to 50 mg/dl).Patients with phenazopyridine medications may show false-positive results.Medications with sodium2-mercaptoethanesulfonate (mesna) can lead to a false-positive or false-negative reading of reagent pad color change." "for diagnostic purposes, the results should always be assessed in conjunction with the patient¿s medical history, clinical examination and other findings." the cause of the event could not be determined, as the chemstrip 10 md urine test strips lot number was not provided.

• Brand Name: URISYS 1100 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: 23008862
• Report Number: 1823260-2025-02800
• Device Sequence Number: 13210505
• Product Code: KHE
• UDI-Device Identifier: 00075537253564
• UDI-Public: 00075537253564
• Combination Product (Y/N): N
• Initial Reporter State: NC
• Initial Reporter Country: US
• PMA/510(K) Number: K033548
• 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): 11/04/2025

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: 03617556001
• 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: 08/20/2025
• Supplement Date Received by Manufacturer: 10/22/2025
• Initial Report FDA Received Date: 09/09/2025
• Supplement Report FDA Received Date: 11/04/2025
• 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