CLINICAL CHEMISTRY AST-ACTIVATED

Additional Manufacturer Narrative

(B)(4). AN INVESTIGATION IS IN PROCESS. A FOLLOW-UP REPORT WILL BE SUBMITTED WHEN THE INVESTIGATION IS COMPLETE.

Additional Manufacturer Narrative

THE PATIENT SAMPLE WAS AVAILABLE AND WAS RETURNED FOR INVESTIGATION. TESTING WAS ALSO PERFORMED ON THE CUSTOMER'S RETURNED PATIENT SERUM SAMPLE WITH FLEX PARAMETERS. THE PATIENT SAMPLE DID NOT GENERATE A <5 U/L (<0.08 UKAT/L) RESULT WHEN RUN UNDILUTED AS OBSERVED BY THE CUSTOMER. UNDILUTED AND DILUTED 1:2 SAMPLES ALL GAVE EITHER ERROR CODE 1350 AND 1351. WHEN THE SAMPLE WAS DILUTED 1:3, THE RESULT WAS >5364 U/L WITH A#2, >, AND FLEX FLAGS. TESTING WAS PERFORMED TO EVALUATE HIGH ACTIVATED ASPARTATE AMINOTRANSFERASE (A-AST) CONCENTRATION SAMPLES WITH FLEX READ TIME AND WITHOUT FLEX READ TIME. SAMPLES WERE PREPARED USING A SERUM POOL AND 4% HUMAN SERUM ALBUMIN (HSA). HIGH SAMPLES WERE PREPARED IN CONCENTRATIONS BETWEEN ~20,000 U/L TO ~200, AND LOW SAMPLES WERE PREPARED IN CONCENTRATIONS OF ~100 TO ~10. ALL SERUM POOL AND 4% HSA SAMPLES GENERATED RESULTS WITHIN STATED ACCEPTANCE CRITERIA. THE SERUM POOL AND 4% HSA SAMPLES ALSO GENERATED RESULTS AND/OR FLAGS APPROPRIATELY BASED ON THE EXPECTED CONCENTRATIONS AND NO <5 U/L RESULTS WERE GENERATED. A QUALITY REVIEW OF COMPLAINT ACTIVITY FOR THE A-AST ASSAY WAS CONDUCTED AND DID NOT IDENTIFY ANY ADVERSE OR NON-STATISTICAL TRENDS FOR PATIENT RESULTS. THE A-AST PACKAGE INSERT WAS REVIEWED AND WAS FOUND TO INCLUDE INFORMATION REGARDING DILUTIONS EXCEEDING LINEARITY AND FLEX RATE LINEARITY PROCEDURES. BASED UPON THE DATA AVAILABLE AND THE RESULTS OF THE EVALUATION, NO PRODUCT DEFICIENCY WAS IDENTIFIED. (B)(4).

Description of Event or Problem

THE CUSTOMER STATED THAT AN ARCHITECT ACTIVATED AST RESULT OF <0.08 U/L WAS GENERATED ON A FEMALE PATIENT. THE PATIENT'S ACTIVATED ALT RESULT WAS 300 U/L. THE ACTIVATED AST RESULT WAS REPEATED USING A MANUAL DILUTION WHICH GENERATED A VERY HIGH RESULT (EXACT VALUE NOT PROVIDED). THE CUSTOMER SUSPECTS THAT SUBSTRATE DEPLETION OCCURRED CAUSING THE INITIAL RESULT TO BE FALSELY LOW. THE INITIAL RESULT WAS REPEATED BECAUSE IT DID NOT ALIGN WITH THE OTHER LABORATORY RESULTS (ELEVATED ALT). DURING A FOLLOW-UP CONVERSATION, THE CUSTOMER STATED THAT THE PATIENT HAD DIED DURING SURGERY DUE TO CARDIAC ARREST. THE INITIAL LOW RESULT WAS NOT REPORTED OUT OF THE LABORATORY AND THERE WAS NO DELAY IN TREATMENT. THE CUSTOMER STATED THAT THE ACTIVATED AST RESULTS DID NOT CAUSE OR CONTRIBUTE TO THE PATIENT DEATH.