ELECSYS T4 ASSAY

Additional Manufacturer Narrative

(B)(4).

Description of Event or Problem

THE CUSTOMER INITIALLY QUESTIONED RESULTS FOR 1 PATIENT TESTED FOR ELECSYS TSH ASSAY (TSH), ELECSYS FT4 II ASSAY (FT4 II), ELECSYS PTH IMMUNOASSAY (PTH) AND ELECSYS T3 (T3) THAT SHOWED DIFFERENT RESULTS USING 3 DIFFERENT TESTING METHODS. THE CUSTOMER THINKS THERE IS AN INTERFERENCE WITH THE ROCHE REAGENTS. THE HIGH FT4 II RESULT IS WHAT MADE THE CUSTOMER INVESTIGATE OTHER THYROID RESULTS FOR THIS PATIENT. THE TSH RESULT WAS NORMAL AND THE ELEVATED FT4 II RESULT DID NOT MATCH THE PATIENT¿S DIAGNOSIS SINCE THE PATIENT DOES NOT HAVE HYPOTHYROIDISM. THREE DIFFERENT SAMPLES FROM THE PATIENT WERE INITIALLY SENT TO 3 DIFFERENT SITES USING VARIOUS TESTING METHODS. BASED ON THE DATA PROVIDED, THE RESULTS FOR TSH, FT4 II AND ELECSYS FT3 III (FT3 III) WERE ERRONEOUS AND REPORTED OUTSIDE OF THE LABORATORY. THE INITIAL ERRONEOUS RESULTS FOR TSH, FT4 II AND FT3 III WERE PREVIOUSLY REPORTED ON MANUFACTURER REPORTS 1823260-2016-01872-00, 1823260-2016-01871-00 AND 1823260-2016-01873-00 RESPECTIVELY. THE CUSTOMER OBTAINED A NEW SAMPLE FROM THE PATIENT ON (B)(6) 2017 AND RAN THYROID TESTS ON THE COBAS 6000 E 601 MODULE AT THE CUSTOMER SITE AND ALSO SENT IT OUT TO AN EXTERNAL LABORATORY USING A SIEMENS SYSTEM. THE CUSTOMER THINKS THE RESULTS FROM THE SIEMENS METHOD ARE CORRECT. BASED ON THE DATA PROVIDED, ADDITIONAL ERRONEOUS RESULTS WERE IDENTIFIED FOR TSH AND FT4 II. NEW ERRONEOUS RESULTS WERE IDENTIFIED FOR ELECSYS T4 ASSAY (T4), T3 AND PTH. THE ERRONEOUS RESULTS WERE REPORTED OUTSIDE OF THE LABORATORY. ADDITIONAL INFORMATION ON THE TSH AND FT4 II RESULTS WILL BE SENT AS A SUPPLEMENTAL TO THOSE REPORTS. THIS MEDWATCH WILL COVER T4. REFER TO MEDWATCH WITH PATIENT IDENTIFIER (B)(6) FOR INFORMATION ON THE T3 ERRONEOUS RESULTS AND MEDWATCH WITH PATIENT IDENTIFIER (B)(6) FOR INFORMATION ON THE PTH ERRONEOUS RESULTS. REFER TO THE ATTACHED DATA FOR PATIENT RESULTS. NO ADVERSE EVENT OCCURRED. THE COBAS 6000 E 601 MODULE SERIAL NUMBER WAS (B)(4).

Additional Manufacturer Narrative

THE PATIENT SAMPLE FROM (B)(6) 2017 WAS SUBMITTED FOR INVESTIGATION. UPON FURTHER INVESTIGATION OF THE PATIENT SAMPLE, A STREPTAVIDIN INTERFERENCE WAS CONFIRMED. THIS MOST LIKELY CAUSED THE HIGH T4 RESULTS. THE REAGENT USED TO PERFORM THE TESTS CONTAINS STREPTAVIDIN. THIS SPECIFIC INTERFERENCE IS ADDRESSED IN PRODUCT LABELING. FOR DIAGNOSTIC PURPOSES, THE RESULTS SHOULD ALWAYS BE ASSESSED IN CONJUNCTION WITH THE PATIENT¿S MEDICAL HISTORY, CLINICAL EXAMINATION AND OTHER FINDINGS.