ELECSYS T4

Additional Manufacturer Narrative

THE SAMPLE WAS REQUESTED FOR INVESTIGATION.

Description of Event or Problem

THE INITIAL REPORTER COMPLAINED OF DISCREPANT HIGH RESULTS FOR 1 PATIENT SAMPLE TESTED FOR ELECSYS T3 (T3), ELECSYS FT3 III (FT3 III) AND ELECSYS T4 (T4) ON A COBAS 8000 CORE UNIT COMPARED TO THE SIEMENS METHOD. THIS MEDWATCH WILL COVER T4. REFER TO MEDWATCH WITH PATIENT IDENTIFIER (B)(6) FOR INFORMATION ON THE FT3 III RESULTS AND MEDWATCH WITH PATIENT IDENTIFIER (B)(6) FOR INFORMATION ON THE T3 RESULTS. THE T3 RESULT FROM THE ROCHE METHOD WAS 3.56 NG/ML. THE RESULT FROM THE SIEMENS METHOD WAS 1.13 NG/ML. THE FT3 III RESULT FROM THE ROCHE METHOD WAS 7.26 PG/ML. THE RESULT FROM THE SIEMENS METHOD WAS 3.22 PG/ML. THE T4 RESULT FROM THE ROCHE METHOD WAS 24.9 UG/DL. THE RESULT FROM THE SIEMENS METHOD WAS 7.78 UG/DL. THE ROCHE RESULTS WERE REPORTED OUTSIDE OF THE LABORATORY WHERE THEY DID NOT CORRESPOND TO THE PATIENT¿S CLINICAL CONDITION. THE SIEMENS RESULTS WERE BELIEVED TO BE "NORMAL." THE COBAS 8000 CORE UNIT SERIAL NUMBER WAS (B)(4).

Additional Manufacturer Narrative

THE SAMPLE WAS RECEIVED FOR INVESTIGATION. THE CUSTOMER'S HIGH RESULTS FOR FT3 III, T4 AND T3 WERE REPRODUCED. FURTHER INVESTIGATION OF THE SAMPLE CONFIRMED AN INTERFERENCE AGAINST THE STREPTAVIDIN COMPONENT OF THE REAGENT. THIS INTERFERENCE CAUSED THE HIGH FT3 III, T4 AND T3 RESULTS AND IS COVERED IN 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." THE INVESTIGATION DID NOT IDENTIFY A PRODUCT PROBLEM.