PROTEIN S AC

Description of Event or Problem

THE CUSTOMER REPORTED THE OBSERVATION OF FALSELY DEPRESSED PROTEIN S AC RESULTS COMPARED TO REPEAT TESTING FOR MULTIPLE PATIENT SAMPLES USING LOT 03229 ON A BCS XP INSTRUMENT. THE FALSELY DEPRESSED RESULTS WERE NOT REPORTED TO THE PHYSICIAN(S). THERE ARE NO KNOWN REPORTS OF PATIENT INTERVENTION OR ADVERSE HEALTH CONSEQUENCES DUE TO THE FALSELY DEPRESSED PROTEIN S AC RESULTS.

Additional Manufacturer Narrative

AN OUTSIDE THE UNITED STATES (OUS) CUSTOMER CONTACTED A SIEMENS REMOTE SUPPORT CENTER TO REPORT THE OBSERVATION OF FALSELY DEPRESSED PROTEIN S AC RESULTS OBTAINED ON A BCS XP INSTRUMENT. PER THE LIMITATIONS SECTION OF THE PROTEIN S AC INSTRUCTIONS FOR USE (IFU): "RESULTS OF THIS TEST SHOULD ALWAYS BE INTERPRETED IN CONJUNCTION WITH THE PATIENT'S MEDICAL HISTORY, CLINICAL PRESENTATION AND OTHER FINDINGS." SIEMENS IS INVESTIGATING.

Additional Manufacturer Narrative

SIEMENS FILED INITIAL MDR 9610806-2025-00017 ON 01-MAY-2025. ADDITIONAL INFORMATION 22-MAY-2025. SIEMENS EVALUATED THIS ISSUE AND PROVIDED THE FOLLOWING CONCLUSION: THE BCS XP SYSTEM APPLICATION SHEET FOR PROTEIN S AC (RG_12_EN-C REV. 5.02), 'ADDITIONAL NOTES' STATE "A FRESHLY RECONSTITUTED BOTTLE OF PROTEIN S AC ACTIVATOR HAS TO BE WARMED-UP TO 37 °C FOR 60 MINUTES. THE FRESHLY RECONSTITUTED REAGENTS PROTEIN S AC REAGENT AND PROTEIN S AC DEFICIENT HAVE TO STAND FOR 60 MINUTES AT 15 TO 25 °C BEFORE USE." IN ADDITION, THE 'ON-BOARD STABILITY' TABLE IN THE APPLICATION SHEET LISTS THE ON-BOARD STABILITY OF THESE MATERIALS AS 2 HOURS. BASED ON THE REVIEW OF THE AVAILABLE DATA, THE FALSELY DEPRESSED PROTEIN S AC RESULTS WERE OBTAINED USING A CALIBRATION PERFORMED AT 10:09 AM. NEW REAGENT WAS PREPARED AND THE ASSAY WAS RECALIBRATED PRIOR TO REPEATING THE SAMPLES. THE REPEAT RESULTS USING THIS RECALIBRATION FROM 11:45 AM WERE REPORTED AS THE CORRECT RESULTS TO THE PHYSICIAN(S). THE PREPARATION OF THE REAGENT USED FOR THE EARLIER CALIBRATION CANNOT BE RULED OUT AS THE CAUSE OF THE FALSELY DEPRESSED RESULTS. BASED ON THE AVAILABLE INFORMATION, THERE IS NO EVIDENCE OF A REAGENT OR INSTRUMENT PROBLEM AND THE CAUSE OF THE DISCORDANT RESULTS IS INCONCLUSIVE. PROTEIN S AC LOT: 03229 IS PERFORMING AS INTENDED. IN SECTION H6, THE INVESTIGATION AND CONCLUSION CODES WERE UPDATED.