ELECSYS C-PEPTIDE

Description of Event or Problem

THE INITIAL REPORTER RECEIVED A QUESTIONABLE ELECSYS C-PEPTIDE (C-PEPTIDE) RESULT FROM ONE PATIENT SAMPLE TESTED ON THE COBAS E 801 ANALYTICAL UNIT WITH SERIAL NUMBER (B)(4). THE INITIAL RESULT WAS REPORTED OUTSIDE OF THE LABORATORY. THE C-PEPTIDE RESULT ALLEGEDLY DID NOT FIT OR WAS NOT PARALLEL TO THE MEASURED ELECSYS INSULIN RESULT. THE INITIAL C-PEPTIDE RESULT WAS >40 NG/ML. THE REPORTER DID A RECYCLING EXPERIMENT WITH POLYETHYLENE GLYCOL (PEG) AND THE RESULT WAS CONSISTENT WITH THE ORIGINAL RESULT. THE INSULIN RESULT WAS 18.2 UU/ML. THIS RESULT WAS WITHIN THE MEASUREMENT RANGE BUT HIGHER THAN THE REFERENCE INTERVAL. THE PATIENT SAMPLE WAS RETESTED FOR INSULIN AND THE RESULTS WERE CONSISTENT THE REAGENT LOT NUMBER AND THE EXPIRATION DATE WERE REQUESTED BUT NOT PROVIDED.

Additional Manufacturer Narrative

THE PATIENT SAMPLE WAS RECEIVED FOR INVESTIGATION. THE PATIENT SAMPLE WAS NOT HEMOLYZED; THE PATIENT SAMPLE WAS NOTED TO BE LIPEMIC. THE RESULTS OF C-PEPTIDE WERE PROPORTIONAL TO THE DILUTION RATIO, WHICH INDICATES THAT THERE WAS NO HOOK EFFECT. THE INVESTIGATION DETERMINED THAT THERE WAS NO INTERFERENCE WITH HETEROPHILE ANTIMOUSE ANTIBODIES (HAMA). THE INVESTIGATION EXCLUDED ALL INTERFERENCES.

Additional Manufacturer Narrative

MEDWATCH FIELD B7: OTHER RELEVANT HISTORY WAS UPDATED.

Additional Manufacturer Narrative

THE INVESTIGATION DETERMINED THAT THERE WAS NO RUTHENIUM (RU) INTERFERENCE IN THE SAMPLE. THE INVESTIGATION DETERMINED THAT THE ISSUE WAS CONSISTENT WITH THE PATIENT'S CHRONIC RENAL INSUFFICIENCY. PRODUCT LABELING STATES "ELEVATED C-PEPTIDE LEVELS MAY ALSO RESULT FROM RENAL INSUFFICIENCY AND OBESITY." THE INVESTIGATION DID NOT IDENTIFY A PRODUCT PROBLEM.