DIMENSION VISTA® CLINICAL CHEMISTRY SYSTEM

Description of Event or Problem

A DISCORDANT LOW IMMUNOGLOBULIN A (IGA) RESULT WAS REPORTED ON A PATIENT SAMPLE. THE RESULT WAS REPORTED TO THE PHYSICIAN WHO QUESTIONED THE RESULT. THE PATIENT WAS TESTED BY AN ALTERNATE METHODOLOGY (ELECTROPHORESIS) AND ELEVATED RESULTS WERE OBTAINED. THE ORIGINAL SAMPLE WAS RETESTED AND AN ELEVATED RESULT WAS OBTAINED AND REPORTED. IT IS UNKNOWN IF PATIENT TREATMENT WAS ALTERED OR PRESCRIBED. THERE IS NO REPORT OF ADVERSE OUTCOME TO THE PATIENT AS A RESULT OF INITIAL FALSELY DEPRESSED IGA RESULT.

Additional Manufacturer Narrative

ANALYSIS OF THE INSTRUMENT AND INSTRUMENT DATA INDICATE THAT THE CAUSE FOR THE FALSELY DEPRESSED IGA RESULT IS UNKNOWN. THE DIMENSION VISTA(R) IGA FLEX(R) REAGENT CARTRIDGE IFU IN THE LIMITATIONS OF "PROCEDURE SECTION STATES: ""THE IGA METHOD HAS BEEN DESIGNED TO MINIMIZE ANTIGEN EXCESS IN THE INITIAL SAMPLE DILUTION. HOWEVER, IT CANNOT BE COMPLETELY ELIMINATED AND IN RARE CASES VERY HIGH IMMUNOGLOBULIN CONCENTRATIONS MAY PRODUCE FALSELY-LOW RESULTS. MONOCLONAL IMMUNOGLOBULINS MAY SHOW REACTIVITY DIFFERENT FROM THE POLYCLONAL CALIBRATOR, WHICH IN ISOLATED CASES MAY LEAD TO ARTIFICIALLY DECREASED OR NON-LINEAR RESULTS."" THE INSTRUMENT IS PERFORMING WITHIN SPECIFICATIONS. NO FURTHER EVALUATION OF THE DEVICE IS REQUIRED.