ELECSYS TACROLIMUS

Additional Manufacturer Narrative

MEDWATCH FIELD D DEVICE IDENTIFICATION SECTION D4 LOT NO WAS UPDATED. THE CUSTOMER CLARIFIED THAT THE INFORMATION PROVIDED FOR PATIENT 2 IS A PARALLEL CONTROL SAMPLE. ADDITIONAL RESULTS WERE PROVIDED FOR PATIENT 1. THE ANALYZER USED FOR THE RESULTS WAS NOT PROVIDED. ON (B)(6) 2025, A SAMPLE DRAWN FROM THE FEMORAL VEIN HAD A RESULT OF 7.7 NG/ML. THE PATIENT WAS REPORTED TO BE IN ICU DURING THIS TIME. ON (B)(6) 2025, A SAMPLE DRAWN FROM THE LINE USED FOR MEDICATION AND PARENTERAL NUTRITION HAD A RESULT OF 27.9 NG/ML. ON (B)(6) 2025, THE RESULT FROM A NEW SAMPLE FROM THE LINE USED FOR MEDICATION AND PARENTERAL NUTRITION WAS 28.5 NG/ML. ON (B)(6) 2025, THE RESULT FROM A NEW SAMPLE FROM THE LINE USED FOR MEDICATION AND PARENTERAL NUTRITION WAS 41.5 NG/ML. ON (B)(6) 2025 A SAMPLE WAS DRAWN FROM THE FEMORAL VEIN AND ANALYZED BY ELECSYS TACROLIMUS WITH A RESULT OF 6.1 NG/ML. THE SAMPLE WAS REPEATED ON (B)(6) 2025 WITH THE MASS SPECTROMETRY ANALYZER, WITH A RESULT OF 6.4 NG/ML. IT WAS ASKED, BUT NOT SPECIFIED WHETHER THIS SAMPLE IS FROM EITHER OF THE ALREADY REPORTED PATIENTS. THE INVESTIGATION DETERMINED THAT THE SAMPLE DRAWN FROM THE CENTRAL LINE WAS NOT ADEQUATE. ALSO, THE DIFFERENCE BETWEEN THE ELECSYS TACROLIMUS AND THE ASSAY USED WITH THE MASS SPECTROMETRY ANALYZER IS THE SAMPLE FROM THE CENTRAL LINE AS WELL. NO ADDITIONAL ROOT CAUSE WAS FOUND.

Additional Manufacturer Narrative

THE COBAS E 801 ANALYTICAL UNIT SERIAL NUMBER IS (B)(6). THE CUSTOMER REPORTED THAT THE QC IS PASSING. THE INVESTIGATION IS ONGOING.

Description of Event or Problem

THERE WAS AN ALLEGATION OF QUESTIONABLE ELECSYS TACROLIMUS RESULTS FROM THE COBAS E 801 ANALYTICAL UNIT FOR TWO PATIENTS. PATIENT 1'S INITIAL RESULT COLLECTED FROM A MEDICATION LINE THAT THE PATIENT RECEIVES PARENTERAL NUTRITION WAS 32.5 NG/ML WITH A MASS SPECTROMETRY ANALYZER. THE RESULT WITH THE E801 WAS 23 NG/ML. A SECOND RESULT AFTER A DILUTION OF 1:2 WAS 11.7 NG/ML. ANOTHER SAMPLE WAS COLLECTED FROM THE DIALYSIS CATHETER WITH THE FOLLOWING RESULTS. THE RESULT WITH A MASS SPECTROMETRY ANALYZER WAS 5.8 NG/ML. THE RESULT WITH THE E801 WAS 6.23 NG/ML. ON (B)(6) 2025, A SAMPLE WAS COLLECTED FROM THE DIALYSIS CATHETER. THE RESULT WITH A MASS SPECTROMETRY ANALYZER WAS 6.7 NG/ML. THE RESULT WITH THE E801 WAS 6.14 NG/ML. ON (B)(6) 2025, A SAMPLE WAS COLLECTED FROM THE MEDICATION LINE WITHOUT PARENTERAL NUTRITION. THE RESULT WITH A MASS SPECTROMETRY ANALYZER WAS 23.9 NG/ML. THE RESULT WITH THE E801 WAS 16.3 NG/ML. PATIENT 2'S INITIAL RESULT WITH A MASS SPECTROMETRY ANALYZER WAS 3.4 NG/ML. THE RESULT WITH THE E801 WAS 4.65 NG/ML.