COBAS U 411 URINE ANALYZER

Description of Event or Problem

THERE WAS AN ALLEGATION OF QUESTIONABLE FALSE NEGATIVE LEUCOCYTE RESULTS WITH THE CHEMSTRIP 10 UA FROM THE COBAS U 411 URINE ANALYZER FOR 6 SAMPLES. 1 EXAMPLE WAS PROVIDED. THE INITIAL RESULT WAS NEGATIVE. DURING A MANUAL MICROSCOPIC RUN, IT SHOWED POSITIVE CLUSTERS OF 50/100 CLUMPS OF WHITE BLOOD CELL (WBC). THE QUESTIONABLE RESULTS WERE NOT RELEASED OUTSIDE OF THE LABORATORY. THE MICROSCOPIC READING OF POSITIVE WAS DEEMED TO BE CORRECT.

Additional Manufacturer Narrative

THE CHEMSTRIP 10 UA LOT NUMBERS ARE 8379908 WITH AN EXPIRATION DATE OS 30-APR-2026. LOT 86099503, WITH AN EXPIRATION DATE OF 31-AUG-2026, WAS USED FOR TROUBLESHOOTING PURPOSES. RETENTION TESTING WAS COMPLETED AND SHOWED NO FALSE NEGATIVE RESULTS, FULFILLING THE REQUIREMENTS. THE INVESTIGATION IS ONGOING.

Additional Manufacturer Narrative

THE RETENTION MATERIALS OF LOT 83799000 AND LOT 86099500, AND THE CUSTOMER MATERIALS OF LOT 83799008 AND 86099503 WERE MEASURED ON A COBAS U411 ANALYZER WITH URINE AND A LEUCOCYTES-DILUTION-SERIES. ALL USED MATERIALS SHOW NO FALSE NEGATIVE RESULTS AND FULFILL OUR REQUIREMENTS. PER PRODUCT LABELING, "IF THE TEST IS TO BE READ VISUALLY, WAIT 60 SECONDS (60-120 SECONDS FOR THE LEUKOCYTE TEST AREA) AND THEN COMPARE THE REACTION COLORS OF THE TEST AREAS WITH THE COLORS ON THE LABEL AND ASSIGN ALWAYS THE VALUES OF THE NEAREST COLOR BLOCK. ANY COLOR CHANGES APPEARING ONLY ALONG THE EDGES OF THE TEST AREAS, OR DEVELOPING AFTER MORE THAN 2 MINUTES, DO NOT HAVE ANY DIAGNOSTIC SIGNIFICANCE." THE INVESTIGATION DETERMINED THAT NO PRODUCT ISSUE COULD BE FOUND FOR THE COMPLAINED LOTS.