ELECSYS FT3 III

Additional Manufacturer Narrative

THE INVESTIGATION ANALYZED THE PATIENT SAMPLE FOR THE PRESENCE OF INTERFERENCE. THE INVESTIGATION CONFIRMED THAT THE PRESENCE OF A STREPTAVIDIN INTERFERING FACTOR IN THE PATIENT SAMPLE LED TO THE ELEVATED ELECSYS FT3 III AND FT4 III RESULTS. PRODUCT LABELING STATES "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."

Additional Manufacturer Narrative

THE SERIAL NUMBER OF THE CUSTOMER'S COBAS 6000 E601 MODULE IS (B)(6). THE PATIENT SAMPLE WAS RECEIVED FOR INVESTIGATION. THE INVESTIGATION IS ONGOING.

Description of Event or Problem

THE INITIAL REPORTER RECEIVED QUESTIONABLE ELECSYS FT4 III AND FT3 III ASSAY RESULTS FROM ONE PATIENT SAMPLE TESTED ON THE COBAS 6000 E601 MODULE. THIS MEDWATCH IS FOR THE FT3 III ASSAY. PLEASE REFER TO A1. PATIENT IDENTIFIER (B)(6) FOR THE FT4 III ASSAY. THE INITIAL RESULT WAS NOT REPORTED OUTSIDE OF THE LABORATORY. THE REPORTER STATED THAT THEIR LABORATORY SUPERVISOR DEEMED THE RESULTS REPORTED BY ROCHE COBAS E601 DID NOT MEET CLINICAL EXPECTATIONS AND WERE UNEXPLAINABLE. THEY CONSIDERED THAT THERE WAS AN INTERFERENCE IN THE FT3 & FT4 ELECTROCHEMILUMINESCENCE IMMUNOASSAYS (ECLIA) THAT LED TO THE ELEVATED RESULTS. THE PATIENT SAMPLE WAS SENT TO TWO OTHER LABORATORIES: LABORATORY 1, WHICH USES A BECKMAN DXI 800 ANALYZER AND LABORATORY 2, WHICH USES AN ABBOTT ARCHITECT. PLEASE REFER TO THE ATTACHMENT (B)(6) FOR THE TABLE CONTAINING THE QUESTIONABLE RESULTS.