DIMENSION VISTA®

Additional Manufacturer Narrative

THE ORIGINAL MDR WAS FILED ON 2017-07-07. ANALYSIS OF THE INSTRUMENT AND INSTRUMENT DATA INDICATE THE CAUSE FOR THE DISCORDANT ELEVATED FREE THYROXINE (FT4) RESULT IS UNKNOWN. NO SAMPLE WAS RETURNED TO SIEMENS FOR TESTING. A SIEMENS HEALTHCARE DIAGNOSTICS HEADQUARTERS SUPPORT CENTER (HSC) REPRESENTATIVE EVALUATED THE INFORMATION AND FOUND THE ELEVATED FREE THYROXINE VALUE IS REPEATABLE, PATIENT SPECIFIC AND DISCORDANT WITH THE FREE TRIIODOTHYRONINE AND THYROID STIMULATING HORMONE VALUES, ALTERNATE METHODOLOGY AND THE CLINICAL IMPRESSION. THE INSTRUCTIONS FOR USE FOR THE FT4 FREE THYROXINE FLEX® REAGENT CARTRIDGE, CONTAINS THE FOLLOWING INFORMATION: "PATIENT SAMPLES MAY CONTAIN HETEROPHILIC ANTIBODIES THAT COULD REACT IN IMMUNOASSAYS TO GIVE A FALSELY ELEVATED OR DEPRESSED RESULT. THIS ASSAY HAS BEEN DESIGNED TO MINIMIZE INTERFERENCE FROM HETEROPHILIC ANTIBODIES. NEVERTHELESS, COMPLETE ELIMINATION OF THIS INTERFERENCE FROM ALL PATIENT SPECIMENS CANNOT BE GUARANTEED. A TEST RESULT THAT IS INCONSISTENT WITH THE CLINICAL PICTURE AND PATIENT HISTORY SHOULD BE INTERPRETED WITH CAUTION. THYROID AUTOANTIBODIES IN HUMAN SERUM MAY INTERFERE AND CAUSE FALSELY ELEVATED FT4 RESULTS." THE DEVICE IS PERFORMING WITHIN SPECIFICATIONS. NO FURTHER EVALUATION OF THE DEVICE IS REQUIRED.

Additional Manufacturer Narrative

THE CUSTOMER CONTACTED SIEMENS HEALTHCARE DIAGNOSTICS. THE CAUSE FOR THE DISCORDANT ELEVATED FT4 RESULT IS UNKNOWN. THE CUSTOMER STATED THAT THE QUALITY CONTROL MET SPECIFICATION DURING TESTING. MDR 2517506-2017-00520 AND 2517506-2017- 00550 WERE FILED FOR THE SAME EVENT. SIEMENS IS INVESTIGATING THE INCIDENT.

Description of Event or Problem

A DISCORDANT ELEVATED FREE THYROXINE (FT4) RESULT WAS OBTAINED ON A PATIENT SAMPLE ON THE DIMENSION VISTA 500 SYSTEM. THE RESULT WAS REPORTED TO THE PHYSICIAN AND QUESTIONED. THE SAME PATIENT SAMPLE WAS TESTED AT AN ALTERNATE FACILITY WITH AN ALTERNATE SIEMEN'S INSTRUMENT AND ALTERNATE METHODOLOGY AND A LOWER RESULT WAS OBTAINED. THERE ARE NO REPORTS OF PATIENT INTERVENTION OR ADVERSE HEALTH CONSEQUENCES AS A RESULT OF THE DISCORDANT ELEVATED FT4 RESULT.