CMV IGG ELECSYS E2G
Received Jun 14, 2023 · Event occurred May 16, 2023
Report 1823260-2023-01970 · MDR key 17130591
Device
Generic name
Cytomegalovirus Immunoassay
Manufacturer
Roche DiagnosticsModel number
NACatalog number
09118551190
Lot number
ASKU
Product problems
- False Negative Result
- False Negative Result
Patient
Unknown
- No Clinical Signs, Symptoms or Conditions
- No Clinical Signs, Symptoms or Conditions
Narrative
Additional Manufacturer Narrative
FOR THE TWO SAMPLES PROVIDED FOR INVESTIGATION, THE FIRST SAMPLE WAS THE COMPLAINED SAMPLE. THIS SAMPLE HAD A SLIGHTLY POSITIVE CMV PCR RESULT AT 150 COPIES. THE SECOND SAMPLE PROVIDED FOR INVESTIGATION WAS INITIALLY TESTED BY THE CUSTOMER ON (B)(6) 2023. THIS SAMPLE RESULTED IN A CMV IGM VALUE OF 1.06 COI (POSITIVE) AND A CMV IGG VALUE OF 0.417 U/ML (NEGATIVE). ON (B)(6) 2023, THE PATIENT WAS MEASURED USING THE CMV PCR METHOD AND THE RESULT WAS POSITIVE WITH 50 COPIES. A THIRD SAMPLE COLLECTED FROM THE SAME PATIENT AND TESTED ON (B)(6) 2023 RESULTED IN A TOXO IGM VALUE OF 0.207 COI. THIS SAMPLE HAD A POSITIVE CMV PCR RESULT AT 50 COPIES.
Additional Manufacturer Narrative
TWO SAMPLES FROM THE PATIENT WERE PROVIDED FOR INVESTIGATION. THE INVESTIGATION COULD REPRODUCE THE RESULTS OBTAINED BY THE CUSTOMER.
Additional Manufacturer Narrative
FOR PCR TESTING, REAL-TIME TAQMAN PROBES AND THERMOCYCLER BIO-RAD CFX 96 WERE USED. FURTHER INVESTIGATIONS PERFORMED WITH THE PATIENT SAMPLES DETERMINED THAT AN ACUTE PRIMARY INFECTION IN THE EARLY PHASE IS INDICATED FOR THE PATIENT. DETECTION OF A SEROCONVERSION TO IGG WAS DELAYED WITH THE ELECSYS CMV IGG ASSAY COMPARED TO OTHER METHODS. EPITOPES REQUIRED FOR THE DETECTION OF THIS RARE SAMPLE ARE NOT SUFFICIENTLY REPRESENTED IN THE ELECSYS CMV IGG ASSAY. BASED ON THE SENSITIVITY CLAIMS FOR THE ELECSYS CMV IGG ASSAY, SINGLE FALSE NEGATIVES CAN OCCUR. THE REAGENT PERFORMS WITHIN SPECIFICATIONS.
Description of Event or Problem
THE INITIAL REPORTER COMPLAINED OF DISCREPANT NEGATIVE RESULTS FOR 1 PATIENT SAMPLE TESTED FOR ELECSYS CMV IGG (CMV IGG) AND ELECSYS CMV IGM (CMV IGM) ON A COBAS E 801 MODULE. THIS MEDWATCH WILL COVER CMV IGG. REFER TO MEDWATCH WITH A1 PATIENT IDENTIFIER PT-82002 FOR INFORMATION ON THE CMV IGM RESULTS. THE CMV IGM RESULT FROM THE E801 MODULE WAS 0.635 COI (NEGATIVE). THE CMV IGG RESULT FROM THE E801 MODULE WAS 0.408 U/ML (NEGATIVE). THE SAMPLE WAS REPEATED BY THE CHORUS METHOD AND THE RESULTS WERE POSITIVE. THE SPECIFIC RESULTS WERE NOT PROVIDED. NO QUESTIONABLE RESULTS WERE REPORTED OUTSIDE OF THE LABORATORY. THE E801 MODULE SERIAL NUMBER WAS (B)(6).
Additional Manufacturer Narrative
THE SAMPLE WAS REQUESTED FOR INVESTIGATION.