ELECSYS CMV IGM

Description of Event or Problem

THERE WAS AN ALLEGATION OF QUESTIONABLE FALSE NEGATIVE CMV IGM ELECSYS RESULTS FROM COBAS E 801 ANALYTICAL UNIT SERIAL NUMBER (B)(4). FOR A SAMPLE COLLECTED ON (B)(6) 2022, THE RESULT WAS NEGATIVE. WHEN TESTED ON A VIDAS ANALYZER, THE RESULT WAS POSITIVE. FOR A SAMPLE COLLECTED ON (B)(6) 2022, THE RESULT WAS NEGATIVE. WHEN TESTED ON A VIDAS ANALYZER, THE RESULT WAS POSITIVE. THE QUESTIONABLE RESULTS WERE REPORTED OUTSIDE OF THE LABORATORY.

Additional Manufacturer Narrative

THE SAMPLES IN QUESTION WERE SUBMITTED FOR INVESTIGATION. FOR THE (B)(6) 2022 SAMPLE: THE CMV IGM RESULT WAS 0.466 COI (NON-REACTIVE). THE CMV IGG RESULT AFTER DILUTION WAS 1724 U/ML (REACTIVE). THE CMV IGG AVIDITY WAS 60.9%. FOR THE (B)(6) 2022 SAMPLE: THE CMV IGM RESULT WAS 0.377 COI (NON-REACTIVE). THE CMV IGG RESULT AFTER DILUTION WAS 1612 U/ML (REACTIVE). THE CMV IGG AVIDITY WAS 61.6%. THE CUSTOMER'S RESULTS WERE REPRODUCIBLE. A GENERAL REAGENT ISSUE CAN BE EXCLUDED. THE INVESTIGATION IS ONGOING.

Additional Manufacturer Narrative

THE CALIBRATION AND QC DATA WERE WITHIN THE EXPECTED RANGES. ADDITIONAL ANALYSIS SHOWED THE SAMPLES CONTAINED CMV-SPECIFIC IGG ANTIBODIES OF HIGH AVIDITY, SUGGESTING THAT OTHER METHODS MIGHT DETECT PERSISTING CMV IGM ANTIBODIES IN THE SAMPLES. THE OBTAINED RESULTS ARE NOT INDICATIVE OF AN EARLY PHASE OF INFECTION WITH CMV. MEDWATCH FIELDS A2 - AGE AT TIME OF EVENT, A3 - SEX, AND B7 - OTHER RELEVANT HISTORY WERE UPDATED.