ASPARTATE AMINOTRANSFERASE ACC. TO IFCC WITHOUT PYRIDOXAL PHOSPHATE ACTIVATION

Additional Manufacturer Narrative

UNIQUE IDENTIFIER (UDI) # (B)(4). THIS EVENT OCCURRED IN (B)(6). THE INVESTIGATION IS ONGOING.

Description of Event or Problem

THE INITIAL REPORTER RECEIVED QUESTIONABLE ASPARTATE AMINOTRANSFERASE WITHOUT PYRIDOXAL PHOSPHATE ACTIVATION (ASTL) RESULTS COMPARED TO ASPARTATE AMINOTRANSFERASE - PYRIDOXAL PHOSPHATE ACTIVATED (ASTP2) RESULTS FOR 1 PATIENT SAMPLE. THE INITIAL RESULT WAS 165 U/L USING THE ASPARTATE AMINOTRANSFERASE - PYRIDOXAL PHOSPHATE ACTIVATED (ASTP2) REAGENT ON A COBAS PRO C503 MODULE, SERIAL NUMBER (B)(4). THE SAMPLE WAS REPEATED ON A COBAS 6000 C501 MODULE USING ASPARTATE AMINOTRANSFERASE WITHOUT PYRIDOXAL PHOSPHATE ACTIVATION (ASTL) AND THE RESULT WAS 52 U/L. THE SAMPLE WAS REPEATED AGAIN ON A COBAS 8000 C702 MODULE USING ASPARTATE AMINOTRANSFERASE WITHOUT PYRIDOXAL PHOSPHATE ACTIVATION (ASTL) AND THE RESULT WAS 52 U/L. THE RESULTS WERE NOT REPORTED OUTSIDE OF THE LABORATORY. THE ASTP2 REAGENT LOT NUMBER AND EXPIRATION DATE WERE REQUESTED BUT NOT PROVIDED.

Additional Manufacturer Narrative

SECTIONS D1-D4 WERE UPDATED D4 UNIQUE IDENTIFIER (UDI) #(B)(4). BASED ON INFORMATION PROVIDED, THE INVESTIGATION DETERMINED THE ISSUE WAS DUE TO REMAINING ERYTHROCYTES IN THE SAMPLE. PRODUCT LABELING STATES: "CONTAMINATION WITH ERYTHROCYTES WILL ELEVATE RESULTS, BECAUSE THE ANALYTE LEVEL IN ERYTHROCYTES IS HIGHER THAN IN NORMAL SERA. THE LEVEL OF INTERFERENCE MAY BE VARIABLE DEPENDING ON THE CONTENT OF ANALYTE IN THE LYSED ERYTHROCYTES." THE INVESTIGATION DETERMINED THE ISSUE WAS CONSISTENT WITH A PRE-ANALYTICAL HANDLING ISSUE.