ADVIA CENTAUR XPT CEA ASSAY

Additional Manufacturer Narrative

THE CAUSE FOR THE DISCORDANT ADVIA CENTAUR XPT/XP CEA RESULT IS UNKNOWN. SIEMENS HEALTHCARE DIAGNOSTICS IS INVESTIGATING. THE INSTRUCTION FOR USE (IFU) LIMITATION SECTION STATES: "WARNING: DO NOT USE THE ADVIA CENTAUR CEA IMMUNOASSAY AS A SCREENING TEST FOR DIAGNOSIS. NOTE: DO NOT INTERPRET LEVELS OF CEA AS ABSOLUTE EVIDENCE OF THE PRESENCE OR THE ABSENCE OF MALIGNANT DISEASE. MEASUREMENTS OF CEA SHOULD ALWAYS BE USED IN CONJUNCTION WITH OTHER DIAGNOSTIC PROCEDURES, INCLUDING INFORMATION FROM THE PATIENT'S CLINICAL EVALUATION. THE CONCENTRATION OF CEA IN A GIVEN SPECIMEN DETERMINED WITH ASSAYS FROM DIFFERENT MANUFACTURERS CAN VARY DUE TO DIFFERENCES IN ASSAY METHODS, CALIBRATION, AND REAGENT SPECIFICITY. CEA DETERMINED WITH DIFFERENT MANUFACTURERS' ASSAYS WILL VARY DEPENDING ON THE METHOD OF STANDARDIZATION AND ANTIBODY SPECIFICITY. WARNING: DO NOT USE THE ADVIA CENTAUR CEA IMMUNOASSAY AS A SCREENING TEST FOR DIAGNOSIS."

Description of Event or Problem

A FALSE LOW ADVIA CENTAUR XPT CEA RESULT WAS OBTAINED ON A PATIENT SAMPLE. THE PATIENT NOTICED THAT THE PREVIOUS RESULT WAS ELEVATED FOR CEA FROM THE HEALTH CHECK. THE CUSTOMER THEN RAN THE SAMPLE ON AN ALTERNATE METHOD AND THE RESULT WAS ELEVATED. THE PATIENT SAMPLE WAS SENT TO ANOTHER LABORATORY FOR TESTING ON TWO ALTERNATE METHODS AND THE ADVIA CENTAUR XP. THE RESULTS ON THE TWO ALTERNATE METHODS WERE ELEVATED AND THE RESULT ON THE ADVIA CENTAUR XP WAS LOW. IT IS UNKNOWN IF PATIENT TREATMENT WAS ALTERED OR PRESCRIBED. THERE WAS NO REPORT OF ADVERSE HEALTH CONSEQUENCES DUE TO THE DISCORDANT ADVIA CENTAUR XP CEA RESULTS.

Additional Manufacturer Narrative

SIEMENS FILED THE INITIAL MDR 1219913-2017-00060 ON MARCH 9, 2017. ON 03/13/2017 ADDITIONAL INFORMATION: THE PATIENT WENT FOR AN ENDOSCOPY AND NO CANCEROUS SYMPTOM WAS FOUND. THE NORMAL RESULT WAS REPORTED TO PATIENT. THE PATIENT SAMPLE RESULT ON THE ADVIA CENTAUR SYSTEM WAS NORMAL BUT ELEVATED ON THE TWO ALTERNATE METHODS. THE PATIENT HAD AN ENDOSCOPY PERFORMED AND NO ISSUES WERE FOUND. THE ALTERNATE METHOD 1 CEA INSTRUCTIONS FOR USE (IFU) INDICATES THAT MECONIUM ANTIGEN (NCA2) INTERACTS WITH THE ANTIBODIES USED IN THEIR ASSAY. AS STATED IN THE IFU FOR THE ADVIA CENTAUR CEA ASSAY, NCA2 DOES NOT CROSS REACT WITH THE ASSAY. THE ALTERNATE METHOD 2 IFU DOES NOT MENTION WHETHER NCA2 CROSS REACTS OR NOT. IT IS POSSIBLE THIS PATIENT SAMPLE CONTAINS NCA2 WHICH IS CROSS REACTING WITH THE ALTERNATE METHOD ASSAYS. THE CAUSE FOR THE DISCORDANT CEA RESULT ID UNKNOWN. THE PATIENT SAMPLE WAS NOT AVAILABLE FOR EVALUATION AT THE MANUFACTURING SITE. THE INSTRUMENT IS PERFORMING WITHIN SPECIFICATIONS. NO FURTHER EVALUATION OF THE DEVICE IS REQUIRED.