DIMENSION®

Additional Manufacturer Narrative

THE CUSTOMER CONTACTED A SIEMENS CUSTOMER CARE CENTER (CCC) FOR THE FALSELY ELEVATED MASS CREATINE KINASE MB ISOENZYME (MMB) RESULTS. SIEMENS HEADQUARTERS SUPPORT CENTER (HSC) HAS REVIEWED THE INFORMATION PROVIDED. THE REVIEW OF INSTRUMENT DATA FILES DID NOT INDICATE ANY ABNORMAL PATTERNS WHEN COMPARED TO OTHER MMB SAMPLES, WHICH INDICATED THAT THE REACTION PERFORMED AS EXPECTED, RULING OUT SAMPLING, INSTRUMENT, OR REAGENT ISSUES. QUALITY CONTROL WAS IN RANGE. HSC REVIEWED PATIENT MEDICATIONS TO RULE OUT POSSIBLE INTERFERENCES. NONE OF THE LISTED MEDICATIONS FOR THE PATIENT PROVIDED TO SIEMENS BY THE CUSTOMER WERE INDICATED IN THE DIMENSION MMB INSTRUCTIONS FOR USE (IFU) LISTINGS FOR ASSAY INTERFERENCE. SIEMENS REQUESTED THE PATIENT SAMPLE TO BE RETURNED TO PERFORM TESTING TO RULE OUT OR CONFIRM NON-SPECIFIC BINDING (NSB)/HETEROPHILE ANTIBODY INTERFERENCE. THE CUSTOMER NO LONGER HAD THE PATIENT SAMPLE; THEREFORE, CONFIRMATION TESTING COULD NOT BE PERFORMED. THE INSTRUCTIONS FOR USE FOR THE MASS CREATINE KINASE MB ISOENZYME FLEX® REAGENT CARTRIDGE CONTAINS THE FOLLOWING INFORMATION: "PATIENT SAMPLES MAY CONTAIN HETEROPHILIC ANTIBODIES THAT COULD REACT WITH IMMUNOASSAYS TO GIVE FALSELY ELEVATED OR DEPRESSED RESULTS. THE DIMENSION EXL MMB ASSAY HAS BEEN DESIGNED TO MINIMIZE INTERFERENCE FROM HETEROPHILIC ANTIBODIES, BUT COMPLETE ELIMINATION OF THIS INTERFERENCE CANNOT BE GUARANTEED." THE CAUSE OF THE DISCORDANT MMB RESULTS IS UNKNOWN. NO PRODUCT NONCONFORMANCE WAS IDENTIFIED. THE INSTRUMENT IS PERFORMING ACCORDING TO SPECIFICATIONS. NO FURTHER EVALUATION OF THE DEVICE IS REQUIRED.

Description of Event or Problem

DISCORDANT MASS CREATINE KINASE MB ISOENZYME (MMB) RESULTS WERE OBTAINED ON A PATIENT SAMPLE ON THE DIMENSION EXL SYSTEM. THE RESULTS WERE NOT REPORTED. THE SAME SAMPLE WAS REPROCESSED AT AN ALTERNATE FACILITY ON AN ALTERNATE METHODOLOGY AND A LOWER RESULT WAS OBTAINED. THERE ARE NO KNOWN REPORTS OF PATIENT INTERVENTION OR ADVERSE HEALTH CONSEQUENCES DUE TO THE DISCORDANT ELEVATED MMB RESULTS. THE PATIENT HAD BEEN SENT TO THE CUSTOMER HOSPITAL FOR EVALUATION FOR MYOCARDIAL INFARCTION.