BECKMAN COULTER INORGANIC PHOSPHOROUS

Additional Manufacturer Narrative

BECKMAN COULTER HAS OBTAINED REACTION MONITORS FOR SOME INITIAL RESULTS BUT NO REPEAT RESULTS WERE PROVIDED BY THE CUSTOMER. A REVIEW OF THE REACTION MONITORS INDICATED THAT THEY WERE ABNORMAL. FURTHER INFORMATION HAD BEEN REQUESTED FROM THE CUSTOMER INCLUDING DETAILS OF PATIENT TREATMENT/DIAGNOSIS, RETURN OF PATIENT SAMPLES FOR INVESTIGATION, ALL REACTION MONITORS OF AFFECTED AND UNAFFECTED SAMPLES, AND FULL REAGENT DETAILS BUT WAS NOT PROVIDED. THE CAUSE OF THE EVENT IS CURRENTLY UNKNOWN BUT MAY BE DUE TO THE PRESENCE OF AN INTERFERENT FROM AN UNKNOWN SOURCE AFFECTING THE INORGANIC PHOSPHOROUS ASSAY.

Description of Event or Problem

THE CUSTOMER REPORTED NOTICING PATIENT SAMPLES WITH ELEVATED DIRECT BILIRUBIN CONCENTRATIONS HAVING A NEGATIVE INTERFERENCE WITH INORGANIC PHOSPHOROUS RESULTS INVOLVING THE BECKMAN COULTER AU640 CLINICAL CHEMISTRY ANALYZER. THE CUSTOMER REPORTED OBTAINING ERRONEOUSLY LOW INORGANIC PHOSPHOROUS RESULTS FOR MULTIPLE PATIENTS WITH HIGH DIRECT BILIRUBIN RESULTS. THE CUSTOMER PROVIDED DATA FOR SIX (6) PATIENT SAMPLES WHICH WERE OBTAINED FROM THE AU640 ANALYZER, AND FROM A DRY SLIDE TECHNOLOGY WHICH WAS PERFORMED BY A DIFFERENT HOSPITAL ON THE CUSTOMER'S BEHALF. THE CUSTOMER ALSO REPORTED ABNORMAL INORGANIC PHOSPHOROUS REACTION MONITORS FOR FOUR (4) PATIENT SAMPLES; HOWEVER, NO REPEAT OR ALTERNATIVE TEST METHOD RESULTS WERE PROVIDED FOR THE FOUR PATIENTS. THE CUSTOMER REPORTED THE RESULTS OUT OF THE LABORATORY AND THERE WAS A CHANGE TO PATIENT TREATMENT IN CONNECTION WITH THIS EVENT. FURTHER INFORMATION HAD BEEN REQUESTED BUT THE CUSTOMER HAS NOT PROVIDED ANY INFORMATION REGARDING THE CHANGE TO PATIENT TREATMENT.

Additional Manufacturer Narrative

ADDITIONAL INFORMATION: BECKMAN COULTER PERFORMED AN EXTENSIVE INVESTIGATION FOR THIS INCIDENT AND THE RESULTS DO NOT INDICATE ANY NEGATIVE INTERFERENCE EFFECT OF BILIRUBIN ON THE BECKMAN COULTER INORGANIC PHOSPHOROUS REAGENT IN QUESTION. THE DIFFERENCE BETWEEN THE BECKMAN COULTER INORGANIC PHOSPHATE RESULTS GENERATED FROM THE AU640 ANALYZER AND THE DRY SLIDE METHODOLOGY APPEARS TO BE PARTLY DUE TO A POSITIVE BIAS OF THE DRY SLIDE METHODOLOGY RESULTS IN COMPARISON WITH THE AU SYSTEMS AND ANALYZERS FROM OTHER DIAGNOSTICS MANUFACTURERS. IT IS ALSO POSSIBLE THAT THERE IS A POSITIVE BIAS IN PHOSPHATE RECOVERY ON THE DRY SLIDE METHODOLOGY WITH INCREASING BILIRUBIN CONCENTRATION WHICH MAY BE ACCENTUATING THE DIFFERENCES OF RESULTS BETWEEN THE SYSTEMS.