THE CUSTOMER ALLEGED A SIGNIFICANT BILIRUBIN INTERFERENCE WITH THE (B)(4) ACETAMINOPHEN APPLICATION. THE CUSTOMER RECEIVED A QUESTIONABLE RESULT FOR ACETAMINOPHEN ON THE ANALYTICAL P MODULE FOR ONE PATIENT SAMPLE COLLECTED FROM A TRANSPLANT PATIENT. THE DATE OF OCCURRENCE WAS NOT PROVIDED. THE INITIAL RESULT FOR ACETAMINOPHEN WAS 130 UMOL/L. THIS RESULT WAS REPORTED OUTSIDE THE LABORATORY. THE BILIRUBIN CONCENTRATION FOR THIS SAMPLE WAS ABOUT 300 UMOL/L. A URINE SAMPLE OBTAINED FROM THE PATIENT WAS TESTED BY (B)(6) AND NO ACETAMINOPHEN WAS DETECTED IN THIS URINE SAMPLE. THE PATIENT WAS TREATED WITH (NAC) N-ACETYL CYSTEINE DUE TO THE QUESTIONABLE ACETAMINOPHEN RESULT OF 130 UMOL/L. NO ADVERSE EVENT HAS BEEN ALLEGED REAGARDING THIS EVENT. THE ACETAMINOPHEN REAGENT LOT NUMBER WAS NOT PROVIDED.
D
Patient 1
N
Patient 1
THE EVENT OCCURRED IN (B)(6).
N
Patient 1
AN URGENT MEDICAL DEVICE CORRECTION WAS ISSUED CONTAINING THE FOLLOWING INFORMATION: THE "LIMITATIONS - INTERFERENCE" SECTION OF THE ACETAMINOPHEN PACKAGE INSERT, E-PACKAGE INSERT, AND METHOD SHEETS WILL BE UPDATED TO MORE CLEARLY INDICATE THE IMPACT OF ICTERIC, HEMOLYTIC, OR LIPEMIC SAMPLES WITH LOW LEVELS OF ACETAMINOPHEN. THE UPDATED ACETAMINOPHEN LABELING (I.E., PACKAGE INSERT, E-PACKAGE INSERT, AND METHOD SHEETS) WILL BE MADE AVAILABLE AS SOON AS POSSIBLE. FALSE POSITIVE ACETAMINOPHEN RESULTS MAY BE OBTAINED FOR ACETAMINOPHEN- FREE SAMPLES IF AN ENDOGENOUS INTERFERENT (I.E., BILIRUBIN, HEMOLYSIS, OR LIPEMIA) IS PRESENT. THIS MAY CAUSE N-ACETYLCYSTEINE TREATMENT TO BE UNNECESSARILY INITIATED IN PATIENTS WITH ELEVATED BILIRUBIN CONCENTRATIONS. SINCE MOST OF THE PATIENTS SEEN WITHIN THE FIRST 24 HOURS OF AN ACUTE ACETAMINOPHEN OVERDOSE PRESENT WITH ONLY SLIGHTLY INCREASED BILIRUBIN CONCENTRATIONS, IT IS UNLIKELY THAT FALSE POSITIVE ACETAMINOPHEN RESULTS WILL OCCUR IN THE SETTING OF ACUTE ACETAMINOPHEN TOXICITY. IN PATIENTS WITH ACUTE LIVER INJURY, THE FALSE POSITIVE RESULTS MAY LEAD TO THE INCORRECT CLINICAL INTERPRETATION THAT THE INJURY IS CAUSED BY ACETAMINOPHEN INGESTION. ENDOGENOUS INTERFERENTS (I.E., BILIRUBIN, HEMOLYSIS, AND/OR LIPEMIA) MAY PRODUCE A FALSELY ELEVATED VALUE FOR SAMPLES CONTAINING CONCENTRATIONS LESS THAN 50 UG/ML OF ACETAMINOPHEN.