ATELLICA IM VITAMIN B12 (VB12)

Additional Manufacturer Narrative

A CUSTOMER FROM OUTSIDE THE UNITED STATES REPORTED OBSERVATION OF ATELLICA IM VITAMIN B12 (VB12) RESULTS WHICH WERE DISCORDANT RELATIVE TO REPEAT TESTING WHEN USING VB12 LOT 299. NO ISSUES WERE IDENTIFIED WITH ASSAY CALIBRATION. THE AFFECTED SAMPLE IS NO LONGER AVAILABLE FOR ADDITIONAL TESTING. SIEMENS IS INVESTIGATING.

Description of Event or Problem

THE CUSTOMER REPORTS OBSERVATION OF AN ELEVATED ATELLICA IM VITAMIN B12 (VB12) RESULT WHICH WAS DISCORDANT RELATIVE TO REPEAT TESTING WHEN USING VB12 LOT 299. THE CUSTOMER IDENTIFIED A NEGATIVE BIAS IN THE RUNNING AVERAGE FOR VB12 QUALITY CONTROL (QC) RESULTS AND PERFORMED REPEAT TESTING OF 33 SAMPLES FOR WHICH RESULTS HAD BEEN PREVIOUSLY REPORTED. TESTING WAS PERFORMED ON AN ALTERNATE ATELLICA IM ANALYZER, FOR WHICH QC WAS APPROVED. WHEN THE SAMPLES WERE RE-TESTED, DIFFERENCES BETWEEN INITIAL AND REPEAT RESULTS WERE VARIABLE, WITH BOTH NEGATIVE AND POSITIVE BIASES. ONLY ONE SAMPLE DEMONSTRATED A POSITIVE BIAS REPRESENTING THE POTENTIAL FOR HARM. THERE ARE NO ALLEGATIONS OF PATIENT HARM, CHANGES IN TREATMENT, OR DELAYS OF DIAGNOSIS IN ASSOCIATION WITH THE OBSERVED DISCORDANCE.

Additional Manufacturer Narrative

A CUSTOMER FROM OUTSIDE THE UNITED STATES REPORTED OBSERVATION OF ATELLICA IM VITAMIN B12 (VB12) RESULTS WHICH WERE DISCORDANT RELATIVE TO REPEAT TESTING. MDR 1219913-2025-00128 WAS SUBMITTED TO THE FDA ON 01-JUL-2025. UPDATE: SIEMENS HAS CONCLUDED INVESTIGATION, 14-JUL-2025. RETURN OF THE PATIENT SAMPLE FOR FURTHER INVESTIGATION IS NOT WARRANTED BECAUSE DISCORDANT RESULT WAS NOT REPRODUCIBLE. SIEMENS REVIEWED INSTRUMENT DATA IN ORDER TO INVESTIGATE THE EVENT. VALID CALIBRATION OF THE VB12 ASSAY WAS PERFORMED ON 24-MAY-2025. SIEMENS PERFORMED A REVIEW OF PRIMARY AND ANCILLARY REAGENT USAGE ASSOCIATED WITH THE DISCORDANT SAMPLE MEASUREMENTS. IT WAS DETERMINED THAT MULTIPLE PACKS OF BOTH PRIMARY AND ANCILLARY REAGENTS WERE CONCURRENTLY IN USE ON THE ATELLICA IM ANALYZER DURING THE PERIOD OF TESTING. DESPITE THE DISCORDANT RESULTS OBSERVED FOR SPECIFIC SAMPLES, MULTIPLE PATIENT SAMPLES TESTED BEFORE AND AFTER THE AFFECTED CASES¿USING THE SAME REAGENT AND ANCILLARY PACKSYIELDED RESULTS WITHOUT SYSTEM ERRORS OR DISCORDANT RESULTS. IT WAS NOTED THAT QUALITY CONTROL (QC) TESTING PRODUCED ACCEPTABLE RESULTS ON THE DAY BEFORE THE DISCORDANT OBSERVATIONS, WHEN THE QC SAMPLES WERE TESTED USING THE SAME PRIMARY REAGENT PACK IN COMBINATION WITH A DIFFERENT ANCILLARY PACK. THE ANCILLARY REAGENT PACK ASSOCIATED WITH THE DISCORDANT RESULTS WAS NOT QC-TESTED PRIOR TO PATIENT TESTING. TO ADDRESS THE OBSERVED DISCORDANCE, THE CUSTOMER REPLACED BOTH THE PRIMARY AND ANCILLARY REAGENT PACKS IN QUESTION WITH ALTERNATE VB12 REAGENT PACKS. SUBSEQUENT TESTING PRODUCED ACCEPTABLE RESULTS, AND NO FURTHER ISSUES WERE REPORTED FOR THE VB12 ASSAY. THE OBSERVATION OF DISCORDANT PATIENT RESULTS CAN BE ISOLATED TO THE ANCILLARY DTT REAGENT USED FOR TESTING. NO OTHER INSTRUMENT OR REAGENT PACK ISSUES WERE IDENTIFIED. THERE IS A POTENTIAL FOR DISCORDANT RESULTS IF THE DTT REAGENT IS NOT ADEQUATELY MIXED DURING PREPARATION, ALLOWED TO SIT BEFORE BEING PLACED IN THE REAGENT COMPARTMENT, OR IF THE VOLUMES USED DURING MANUAL PREPARATION DEVIATE FROM THE SPECIFIED AMOUNTS. IT IS RECOMMENDED THAT THE REAGENT PREPARER REVIEW THE PROPER PREPARATION AND HANDLING PROCEDURES FOR THE DTT/RELEASING AGENT AS OUTLINED IN THE ATELLICA IM VB12 INFORMATION FOR USER, 10995437_EN REV. 02, 2019-08. ALTHOUGH THE SPECIFIC CAUSE FOR THE DISCORDANT RESULTS WAS NOT DEFINITIVELY IDENTIFIED, BASED ON THE AVAILABLE DATA, THE DISCORDANT RESULT IS LIKELY ATTRIBUTABLE TO A PROBLEM WITH THE ANCILLARY DTT REAGENT. THE CUSTOMER IS OPERATIONAL, AND THE REPORTED ISSUE WAS RESOLVED BY ROUTINE TROUBLESHOOTING. NO SYSTEMIC PRODUCT PROBLEMS WERE IDENTIFIED. NOTE: IN SECTION H6, THE CODES FOR INVESTIGATION FINDINGS AND INVESTIGATION CONCLUSIONS HAVE BEEN UPDATED.