ELECSYS FT3 III

Additional Manufacturer Narrative

THE SAMPLE WAS PROVIDED FOR INVESTIGATION. THE CUSTOMER'S HIGH FT3 V2 VALUE COULD BE REPRODUCED. FURTHER INVESTIGATIONS OF THE SAMPLE DETERMINED IT CONTAINS AN INTERFERING FACTOR AGAINST THE IDIOTYPE OF THE MONOCLONAL ANTIBODY OF THE FT3 ASSAY. THIS CAUSED THE FALSELY ELEVATED VALUE FOR THE FT3 V2 ASSAY. PER PRODUCT LABELING: "IN RARE CASES, INTERFERENCE DUE TO EXTREMELY HIGH TITERS OF ANTIBODIES TO ANALYTE-SPECIFIC ANTIBODIES, STREPTAVIDIN OR RUTHENIUM CAN OCCUR. THESE EFFECTS ARE MINIMIZED BY SUITABLE TEST DESIGN. FOR DIAGNOSTIC PURPOSES, THE RESULTS SHOULD ALWAYS BE ASSESSED IN CONJUNCTION WITH THE PATIENT¿S MEDICAL HISTORY, CLINICAL EXAMINATION AND OTHER FINDINGS."

Description of Event or Problem

THE INITIAL REPORTER STATED THEY RECEIVED DISCREPANT RESULTS FOR ONE PATIENT SAMPLE TESTED WITH ELECSYS FT3 III VER. 2 (FT3 V2) ASSAY ON MULTIPLE ROCHE ANALYZERS. AN INTERFERENCE IS SUSPECTED. NO INCORRECT RESULTS WERE REPORTED OUTSIDE OF THE LABORATORY. THE SAMPLE WAS COLLECTED ON (B)(6)2023 AND INITIALLY TESTED WITH FT3 V2 ON THE CUSTOMER'S COBAS E 801 MODULE ON AN UNKNOWN DATE. THE SAMPLE WAS TREATED WITH A 25 % POLYETHYLENE GLYCOL (PEG) SOLUTION AND REPEATED ON THE CUSTOMER'S COBAS E 801 MODULE. THE SAMPLE WAS REPEATED USING THE WAKO ACCURASEED FT3 METHOD. THE SAMPLE WAS PROVIDED FOR INVESTIGATION, WHERE IT WAS TESTED WITH THE FT3 V2 ASSAY ON A SECOND E 801 ANALYZER ON (B)(6)2023. DURING INVESTIGATIONS, THE SAMPLE WAS ALSO TESTED WITH THE FT3 V2 ASSAY ON A COBAS E 411 ANALYZER. THE SAMPLE WAS ALSO REPEATED USING THE ABBOTT ARCHITECT FT3 METHOD ON (B)(6)2023. REFER TO THE ATTACHMENT FOR ALL RELEVANT PATIENT RESULTS. THE SERIAL NUMBER OF THE CUSTOMER'S E 801 ANALYZER IS (B)(4). THE FT3 V2 REAGENT LOT NUMBER AND EXPIRATION DATE USED ON THIS ANALYZER WERE REQUESTED, BUT NOT PROVIDED. THE SERIAL NUMBER OF THE E 801 ANALYZER USED FOR INVESTIGATION IS (B)(4). FT3 V2 REAGENT LOT NUMBER 653314, WITH AN EXPIRATION DATE OF 31-DEC-2023 WAS USED ON THIS ANALYZER. THE SERIAL NUMBER OF THE E411 ANALYZER USED FOR INVESTIGATION IS (B)(4). FT3 V2 REAGENT LOT NUMBER 611918, WITH AN EXPIRATION DATE OF 30-MAY-2023 WAS USED ON THIS ANALYZER.

Additional Manufacturer Narrative

THE SAMPLE WAS REQUESTED FOR INVESTIGATION.