Description of Event or Problem · 1
IN 2005, A BAYER TECHNICAL SERVICE SPECIALIST REPORTED THAT A CUSTOMER HAD SENT OUT ERRONEOUSLY LOW RESULTS FOR A PATIENT'S CK [CREATINE KINASE] LEVEL. A PATIENT'S AVERAGE CK VALUES FOR ONE SAMPLE WAS REPORTED AS 18 AND 7 U/L ON TWO DIFFERENT AVIA 1650 CHEMISTRY ANALYZERS. REACTION CURVES INDICATED THAT THE SAMPLE EXHAUSTED THE SUBSTRATE RAPIDLY BEFORE THE READ POINTS BEGAN. IN ADDITION, THE FALSELY LOW RESULTS WERE NOT FLAGGED BY THE INSTRUMENT. THE CUSTOMER THEN DILUTED THE SAMPLE AND THE RESULT WAS GREATER THAN 200,000 U/L ON DILUTION. THE ANALYTICAL RANGE IN BAYER'S INSTRUCTION FOR USE ARE 0 U/L TO 1,300 U/L. THE PATIENT WAS KNOWN TO HAVE RHABDOMYELOSIS, THESE RESULTS DID NOT RESULT IN ANY UNUSUAL TREATMENT OF THE PATIENT. THE SAMPLE WAS SENT TO BAYER FOR FURTHER TESTING AND ANALYSIS. UPON FURTHER INVESTIGATION IT WAS DETERMINED THAT THE CONDITION AT THE CUSTOMER SITE COULD PRESENT ITSELF AGAIN WITH A SAMPLE WITH UNUSUALLY HIGH CK (>400,000 U/L). A SAMPLE WITH THAT HIGH LEVEL OF CK WOULD DEPLETE THE SUBSTRATE SO RAPIDLY THE SYSTEM CHECK WOULD NOT BE ABLE TO DETECT IT AND THERE COULD BE NO FLAGS ASSOCIATED WITH THE RESULTS. THIS EVENT IS BEING REPORTED SINCE THERE IS THE POTENTIAL THAT THE DEVICE MAY FAIL TO FLAG A SAMPLE WITH AN UNUSUALLY HIGH LEVEL OF CK WHICH IS USED AS A SINGLE TEST WHEN LOOKING FOR RHABDOMYELOSIS AND OTHER FORMS OF SKELETAL MUSCLE NECROSIS. WERE THIS EVENT TO RECUR MISSING A PATIENT WITH RHABDOMYELOSIS COULD LEAD TO SERIOUS ADVERSE CONSEQUENCES. APPROPRIATE PREVENTATIVE MEASURES ARE BEING INVESTIGATED TO ENSURE SAMPLES WITH AN UNUSALLY HIGH LEVEL OF CK ARE FLAGGED BY THE INSTRUMENT.