HEMOSIL SYNTHASIL

Description of Event or Problem

ON (B)(6) 2026, THE CUSTOMER REPORTED DISCREPANT PT AND PTT PATIENT RESULTS GENERATED ON ACL TOP 550 CTS SN (B)(6), (PN 00000280045) AND ANOTHER ANALYZER USING HEMOSIL SYNTHASIL LOT N0754328 (PN 00020006800) AND HEMOSIL RECOMBIPLASTIN 2G (20ML), LOT N0159343, (PN 00020003050). USER REPORTED MULTIPLE ERRONEOUS PT/APTT RESULTS OVER A TWO-DAY PERIOD, WITH 60 CORRECTED REPORTS GENERATED AND 130 ADDITIONAL SAMPLES CANCELED DUE TO THE SAMPLES BEING TOO OLD TO RETEST. ALL ERRONEOUS RESULTS WERE LOWER THAN THE CORRECTED RESULTS. NO PATIENT IMPACT REPORTED.

Additional Manufacturer Narrative

A REVIEW OF THE CERTIFICATES OF ANALYSIS FOR HEMOSIL SYNTHASIL (LOT N0754328) AND HEMOSIL RECOMBIPLASTIN 2G (20 ML, LOT N0159343) CONFIRMED THAT ALL REAGENTS MET RELEASE SPECIFICATIONS WITH NO ABNORMALITIES. PACKAGE INSERT ACCEPTANCE RANGES FOR HEMOSIL NORMAL CONTROL 1 (LOT N0946203) AND HEMOSIL ABNORMAL CONTROL 3 (LOT N0159179) WERE VERIFIED AND FOUND TO BE APPROPRIATE. INSTRUMENT DATA FROM THE ACL TOP 550 CTS (SERIAL NO. (B)(6)) DEMONSTRATED USE OF WERFEN-LOCKED TEST AND MATERIAL DEFINITIONS. QC REVIEW IDENTIFIED A TRANSIENT OUT-OF-RANGE APTT-SYNTHASIL (APTT-SS) RESULT FOR HEMOSIL ABNORMAL CONTROL 3 ON (B)(6) 2026, FOLLOWED BY SUBSEQUENT RECOVERIES WITHIN ACCEPTANCE RANGES. ALL OTHER PT AND APTT QUALITY CONTROL RESULTS REVIEWED WERE WITHIN PACKAGE INSERT SPECIFICATIONS. SAMPLE AND GENERAL INSTRUMENT LOGS SHOWED NO INSTRUMENT ALARMS OR MECHANICAL ERRORS. WHILE SOME PATIENT SAMPLES DISPLAYED ABNORMAL CLOT CURVES AND PROCESSING ERRORS, NO CONSISTENT PATTERN SUGGESTING INSTRUMENT MALFUNCTION OR REAGENT FAILURE WAS IDENTIFIED. THE INVESTIGATION RULED OUT INSTRUMENT MECHANICAL ISSUES, REAGENT HANDLING FAILURES, ASPIRATION ERRORS, AND REAGENT CONTAMINATION AS CONTRIBUTING FACTORS. THE ROOT CAUSE OF THE SHORTENED PT AND APTT RESULTS WAS DETERMINED TO BE CARRYOVER FROM THROMBIN-BASED AND ANTI-XA ASSAYS DUE TO COMPROMISED CLEAN B DILUTED IN COMBINATION WITH HIGHER THAN AVERAGE THROUGHPUT OF Q.F.A. (THROMBIN) AND ANTI-XA TESTING ON (B)(6) 2026. REVIEW OF MAINTENANCE RECORDS INDICATED CLEAN B DILUTED VOLUMES CONSISTENTLY OUTSIDE EXPECTED PREPARATION RANGES, SUGGESTING IMPROPER PREPARATION PRACTICES THAT MAY HAVE INCREASED CARRYOVER RISK UNDER ELEVATED TEST VOLUME CONDITIONS. ACTION TAKEN TO ADDRESS THE ISSUE INCLUDED A FULL SYSTEM INSPECTION, REPLACEMENT AND CALIBRATION OF THE SAMPLE PROBE, VERIFICATION OF PROBE PRECISION, AND SYSTEM VALIDATION WITH NO QC FAILURES OBSERVED. PATIENT CORRELATION STUDIES WITH A SECOND ACL TOP ANALYZER DEMONSTRATED CONCORDANT RESULTS. THE INSTRUMENT WAS RETURNED TO SERVICE FOLLOWING MEDICAL DIRECTOR APPROVAL, AND NO FURTHER ISSUES HAVE BEEN REPORTED. THERE IS NO EVIDENCE TO INDICATE A MANUFACTURING, DESIGN, OR LABELING ISSUE WITH THE PRODUCTS. REINFORCEMENT OF PROPER CLEAN B DILUTED PREPARATION AND ADHERENCE TO ENHANCED CLEANING RECOMMENDATIONS FOR HIGH THROMBIN AND ANTI-XA TEST VOLUMES WERE PROVIDED. BASED ON THIS ASSESSMENT, NO FURTHER REMEDIAL ACTIONS ARE REQUIRED. THIS INCIDENT WILL BE MONITORED THROUGH TRENDING ANALYSIS.