N LATEX FLC KAPPA

Additional Manufacturer Narrative

THE CUSTOMER CONTACTED A SIEMENS CUSTOMER CARE CENTER AND REPORTED THAT DIFFERENT FLC KAPPA RESULTS WERE OBTAINED ON A PATIENT SAMPLE ON A BN PROSPEC SYSTEM USING N LATEX FLC KAPPA REAGENT (LOT NUMBER: 473145) WHEN RUNNING THE SAMPLE IN DIFFERENT DILUTIONS. SIEMENS INVESTIGATED THE ISSUE AND DETERMINED THAT THE KINETIC CURVES FIT THE OBSERVED RESULT VALUES. QUALITY CONTROL RESULTS WERE WITHIN SPECIFICATIONS. A POTENTIAL CAUSE FOR THE RESULT DISCREPANCIES FOR THIS ONE SINGLE PATIENT SAMPLE IN THE DIFFERENT SAMPLE DILUTIONS IS THAT HIGH CONCENTRATIONS OF BOUND-LIGHT CHAINS MAY INFLUENCE FLC KAPPA RESULTS. AS PER THE INSTRUCTIONS FOR USE (IFU) FOR N LATEX FLC KAPPA, "EXCESSIVELY ELEVATED MONOCLONAL IMMUNOGLOBULIN CONCENTRATIONS MIGHT HAVE THE POTENTIAL TO SUPPRESS THE REACTION OF ANTI-FLC ANTIBODIES WITH FREE LIGHT CHAIN MOLECULES". IF RESULTS DO NOT MATCH PREVIOUS RESULTS, IT IS RECOMMENDED TO RE-ANALYZE THE SAMPLE IN A HIGHER SAMPLE DILUTION. THE CAUSE OF THE EVENT IS UNKNOWN AND IS LIMITED TO THIS SINGLE PATIENT SAMPLE. THE REAGENT IS PERFORMING ACCORDING TO SPECIFICATIONS. NO FURTHER EVALUATION OF THIS DEVICE IS REQUIRED.

Description of Event or Problem

THE CUSTOMER REPORTED THAT DIFFERENT FLC KAPPA RESULTS WERE OBTAINED ON A PATIENT SAMPLE ON A BN PROSPEC SYSTEM USING N LATEX FLC KAPPA REAGENT (LOT NUMBER: 473145) WHEN RUNNING THE SAMPLE IN DIFFERENT DILUTIONS. IT IS UNKNOWN IF ANY OF THESE RESULTS WERE REPORTED TO THE PHYSICIAN(S). THE CORRECT RESULTS FOR THIS PATIENT ARE UNKNOWN. THERE ARE NO KNOWN REPORTS OF PATIENT INTERVENTION OR ADVERSE HEALTH CONSEQUENCES DUE TO THE DIFFERENT FLC KAPPA RESULTS.