ELECSYS CK-MB

Additional Manufacturer Narrative

INITIAL REPORTER ADDRESS: (B)(6). QC WAS ACCEPTABLE ON THE DATE OF THE EVENT. FIVE SAMPLE-RELATED ALARMS WERE OBSERVED ON THE ALARM TRACE DATA. PRECISION TESTING WAS PERFORMED. THE ORIGINAL SAMPLE WAS STORED FOR 3 DAYS AT 2 8 °C. PRODUCT LABELING STATES THE SAMPLE IS: "STABLE FOR 5 HOURS AT 20 25 °C, 12 HOURS AT 2 8 °C, 3 MONTHS AT 20 °C (± 5 °C). FREEZE ONLY ONCE. CK MB STABILITY IS EXTREMELY TEMPERATURE-DEPENDENT. A CK MB DECREASE OF > 10 % CAN OCCUR AFTER THE SAMPLE HAS STOOD FOR 1 HOUR AT 32 °C." THE PATIENT SUFFERS FROM MYELOPROLIFERATIVE NEOPLASMS (MPN), AND WHEN USING HEPARIN TUBES THE BLOOD VISCOSITY INCREASES. THIS MAY LEAD TO A DROP AT THE TIP OF THE SAMPLE PROBE, WHICH COULD LEAD TO A HIGH RESULT. CLOTS COULD ALSO INFLUENCE THE RESULTS. BASED ON THE DATA PROVIDED, THE CAUSE OF THE EVENT COULD NOT BE DETERMINED. A GENERAL REAGENT ISSUE CAN BE EXCLUDED. QC DATA DOES NOT SUGGEST A GENERAL REAGENT OR INSTRUMENT ISSUE. THE INVESTIGATION DID NOT IDENTIFY A PRODUCT PROBLEM.

Description of Event or Problem

THE INITIAL REPORTER COMPLAINED OF A DISCREPANT HIGH RESULT FOR 1 PATIENT SAMPLE TESTED FOR ELECSYS CK-MB (CK-MB) ON A COBAS E 801 ANALYTICAL UNIT. THE INITIAL RESULT WAS 83.8 NG/ML. THIS RESULT WAS REPORTED OUTSIDE OF THE LABORATORY. ON (B)(6) 2023 A NEW SAMPLE WAS OBTAINED AND THE CK-MB RESULT WAS 1.65 NG/ML. THE CUSTOMER NOTED THAT THE INITIAL CK-MB RESULT WAS GREATER THAN THE PATIENT'S INITIAL CK RESULT AND PULLED THE ORIGINAL SAMPLE FOR RE-TESTING. ON (B)(6) 2023 THE ORIGINAL SAMPLE WAS REPEATED WITH A CK-MB RESULT OF 2.52 NG/ML. THE E801 MODULE SERIAL NUMBER WAS (B)(4).