ELECSYS VITAMIN B12 II

Additional Manufacturer Narrative

THE SERIAL NUMBER OF THE CUSTOMER'S COBAS E 801 ANALYTICAL UNIT IS (B)(6). THE PATIENT SAMPLE WAS REQUESTED FOR INVESTIGATION. THE INVESTIGATION IS ONGOING.

Description of Event or Problem

THE INITIAL REPORTER RECEIVED QUESTIONABLE ELECSYS VITAMIN B12 II (B12 II) RESULTS FROM TWO SAMPLES FROM THE SAME PATIENT TESTED ON THE COBAS E 801 ANALYTICAL UNIT. THE REPORTER STATED THAT THE CLINICIAN ASKED IF KNOWN INTERFERENCE FACTORS WERE PRESENT BECAUSE THE RESULTS WERE TOO HIGH AND DID NOT MATCH THE CLINICAL PICTURE FOR PERNICIOUS ANEMIA. ON (B)(6) 2024: THE RESULT WAS 977 NG/L. ON (B)(6) 2024: THE RESULT WAS 1082 NG/L.

Additional Manufacturer Narrative

THE PATIENT SAMPLE WAS RECEIVED FOR INVESTIGATION. THE PATIENT SAMPLE WAS TESTED FOR THE PRESENCE OF AN INTERFERENT; AN INTERFERENT WAS NOT DETECTED. THE PATIENT SAMPLE WAS TESTED FOR REACTIVITY FOR VITAMIN B12 MAINLY BOUND TO HAPTOCORRIN AND TRANSCOBALAMIN II AND REACTIVITY WAS DETECTED. A HIGH REACTIVITY FOR UNBOUND VITAMIN B12 WAS ALSO DETECTED. THE PATIENT SAMPLE WAS FURTHER TESTED IN AN EXTERNAL LABORATORY USING A NON-ROCHE METHOD AND THE HIGH VITAMIN B12 VALUE COULD NOT BE CONFIRMED. PRODUCT LABELING STATES "FOR DIAGNOSTIC PURPOSES, THE RESULTS SHOULD ALWAYS BE ASSESSED IN CONJUNCTION WITH THE PATIENT¿S MEDICAL HISTORY, CLINICAL EXAMINATION AND OTHER FINDINGS." THE INVESTIGATION DID NOT IDENTIFY A PRODUCT PROBLEM. THE CAUSE OF THE EVENT COULD NOT BE DETERMINED.