ATELLICA IM CMV IGG (CMV IGG)

Description of Event or Problem

THE CUSTOMER REPORTS OBSERVATION OF A NONREACTIVE (NEGATIVE) ATELLICA IM CMV IGG (CMV IGG) RESULT WHEN USING LOT 071 WHICH WAS DISCORDANT RELATIVE TO REPEAT TESTING USING LOT 072. IN (B)(6) 2024, A NONREACTIVE (NEGATIVE) ATELLICA IM CMV IGG RESULT WAS OBTAINED FOR A 33-YEAR-OLD PREGNANT FEMALE PATIENT. WHEN THE PATIENT WAS RE-SAMPLED IN FEBRUARY, A REACTIVE (POSITIVE) RESULT WAS PRODUCED. THE FIRST SAMPLE (FROM DECEMBER) WAS RE-TESTED IN MARCH USING CMV IGG LOT 072, AND PRODUCED A REACTIVE (POSITIVE) RESULT.. THE SECOND SAMPLE (FROM FEBRUARY) COULD NOT BE RE-TESTED DUE TO INSUFFICIENT VOLUME. WHEN THE SAME PATIENT WAS DRAWN AND TESTED AGAIN IN MARCH (USING CMV IGG LOT 072), ANOTHER REACTIVE RESULT WAS OBTAINED. THE REPRODUCIBLY REACTIVE RESULTS WERE ACCEPTED AS CORRECT. THERE ARE NO ALLEGATIONS OF ANY ADVERSE PATIENT CONSEQUENCES ASSOCIATED WITH THE EARLIER DISCORDANT RESULT.

Additional Manufacturer Narrative

A CUSTOMER FROM OUTSIDE THE UNITED STATES REPORTED OBSERVATION OF A NONREACTIVE (NEGATIVE) ATELLICA IM CMV IGG (CMV IGG) RESULT WHICH WAS DISCORDANT RELATIVE TO REPEAT TESTING. SIEMENS IS INVESTIGATING. NOTE: THE ATELLICA IM CMV IGG (CMV IGG) ASSAY IS MARKETED IN THE UNITED STATES UNDER SIEMENS MATERIAL NUMBER 11202208; THE 510(K) NUMBER DOCUMENTED IN SECTION G4 IS FOR THIS PRODUCT,

Additional Manufacturer Narrative

A CUSTOMER FROM OUTSIDE THE UNITED STATES REPORTED OBSERVATION OF A NONREACTIVE (NEGATIVE) ATELLICA IM CMV IGG (CMV IGG) RESULT WHEN USING LOT 071 WHICH WAS DISCORDANT RELATIVE TO REPEAT TESTING USING LOT 072. THE NONREACTIVE RESULT WAS CONSIDERED ERRONEOUS. MDR 1219913-2025-00055 WAS INITIALLY SUBMITTED ON 17-MAR-2025. UPDATE, 28-AUG-2025: SIEMENS HAS CONCLUDED INVESTIGATION. ASSAY CALIBRATION AND QUALITY CONTROL (QC) RESULTS WERE REVIEWED AND FOUND ACCEPTABLE. SAMPLES FROM THE AFFECTED PATIENT WERE PROVIDED TO SIEMENS FOR ADDITIONAL TESTING. THESE SAMPLES WERE TESTED USING ATELLICA IM CMV IGG, LOT 071 AS WELL AS USING IMMULITE CMV IGG LOT 378. RESULTS FROM BOTH ASSAYS WERE NONREACTIVE (NEGATIVE) FOR BOTH METHODS. REVIEW OF PATIENT HISTORY SHOWS THAT A NONREACTIVE RESULT (FROM CMV IGG LOT 071) WAS FOLLOWED BY REACTIVE RESULTS PRODUCED USING LOT 072. THE PATTERN OF RESULTS SUGGESTS THE POSSIBILITY THAT THE REACTIVE (POSITIVE) DETERMINATIONS MADE USING LOT 072 MAY BE ERRONEOUS, RATHER THAN THE NONREACTIVE LOT-071 RESULT. THE AFFECTED PATIENT HAS NOT RETURNED FOR ADDITIONAL TESTING SINCE MARCH, 2025. AVIDITY TESTING RECOMMENDED BY SIEMENS WAS NOT PERFORMED. THE CUSTOMER IS OPERATIONAL AND NOT REQUESTING ANY FURTHER FOLLOW-UP. THERE IS INSUFFICIENT INFORMATION TO DEFINITIVELY DETERMINE WHICH RESULT WAS CORRECT, AND A CAUSE FOR THE OBSERVED DISCORDANCE WAS NOT IDENTIFIED. NO SYSTEMIC PRODUCT PROBLEM WAS IDENTIFIED. NOTE: IN SECTION H6, THE CODES FOR INVESTIGATION FINDINGS AND INVESTIGATION CONCLUSIONS HAVE BEEN UPDATED.