BC VON WILLEBRAND REAGENT

Additional Manufacturer Narrative

THE CUSTOMER CONTACTED A SIEMENS CUSTOMER CARE CENTER (CCC). QUALITY CONTROLS (QC) RECOVERED IN RANGE AT THE TIME OF THE EVENT. A SIEMENS CUSTOMER SERVICE ENGINEER (CSE) WAS DISPATCHED TO THE CUSTOMER SITE. THE CSE CHANGED THE PISTON OF THE MASTER VALVE 1 (MV1) ON THE SYSMEX CS-2100I SYSTEM AFTER NOTICING AIR LEAKAGE IN THE VALVE. HOWEVER, THE CUSTOMER HAD NOT NOTICED SAMPLE PROBE LEAKAGE ON THE DAY OF THE EVENT OR AFTERWARD. IF THERE WERE A DEFECT IN THE MV1 TO CAUSE IT TO REMAIN OPEN, THE DILUTION OF SAMPLES WOULD HAVE OCCURRED WITH HIGHER FREQUENCY AND THE PROBE WOULD HAVE LEFT A NOTICEABLE TRAIL OF WATER ALONG ITS PATH. NO OTHER PATIENT SAMPLES WERE REPORTED TO BE AFFECTED. SPECIMEN COLLECTION AND SAMPLE HANDLING ISSUES CANNOT BE RULED OUT AS POTENTIAL CAUSES OF THE EVENT. THE CAUSE OF THE EVENT IS UNKNOWN. THE REAGENT IS PERFORMING ACCORDING TO SPECIFICATIONS. NO FURTHER EVALUATION OF THIS DEVICE IS REQUIRED. MDR 9610806-2021-00029 WAS ALSO FILED FOR THE DISCORDANT RESULT OBTAINED ON (B)(6) 2021.

Description of Event or Problem

A DISCORDANT, FALSELY LOW VON WILLEBRAND FACTOR ACTIVITY (VWF AC) RESULT WAS OBTAINED USING AN ALIQUOT FROM A PATIENT SAMPLE ON A SYSMEX CS-2100I SYSTEM USING BC VON WILLEBRAND REAGENT. THE DISCORDANT RESULT WAS REPORTED TO THE PHYSICIAN(S). A SECOND ALIQUOT WAS CREATED FROM THE SAME PATIENT SAMPLE ON THE SAME DAY, BUT WAS NOT RUN. THE NEXT MONTH, THE PATIENT RETURNED TO THE HOSPITAL AND WAS REDRAWN AND RETESTED FOR VWF AC, WHICH RESULTED HIGHER THAN THE RESULT FROM THE PREVIOUS MONTH. THIS HIGHER RESULT WAS REPORTED AS THE CORRECT RESULT TO THE PHYSICIAN(S). THE TWO ALIQUOTS FROM THE PREVIOUS MONTH WERE THEN REPEATED FOR VWF AC. THE FIRST ALIQUOT AGAIN RECOVERED FALSELY LOW, WHILE THE RESULT FROM THE SECOND ALIQUOT MATCHED THE HIGHER RESULT FROM THE NEWLY DRAWN SAMPLE. THERE ARE NO KNOWN REPORTS OF PATIENT INTERVENTION OR ADVERSE HEALTH CONSEQUENCES DUE TO THE DISCORDANT, FALSELY LOW VON WILLEBRAND FACTOR ACTIVITY (VWF AC) RESULTS.