BEUDAMED
    FDA Adverse Event Malfunction Summary report: N

    PHENYTOIN

    MDR report key: 2883704 · Received December 21, 2012

    Report

    Report Number
    1823260-2012-06494
    Event Type
    Malfunction
    Date Received
    December 21, 2012
    Date of Event
    December 7, 2012
    Report Date
    April 9, 2013
    Manufacturer
    ROCHE DIAGNOSTICS
    Product Code
    DIP
    PMA / PMN Number
    K030428
    Removal / Correction Number
    NA
    Product Problem
    Yes
    Report Source
    Manufacturer report
    Reporter Location
    WA, US
    Reporter Occupation
    HEALTH PROFESSIONAL

    Narratives

    Additional Manufacturer Narrative · 1

    IT HAS BEEN DETERMINED THAT THE PATIENT IN QUESTION HAS NOT BEEN DIAGNOSED WITH HUMAN ANTI-MOUSE ANTIBODY (HETEROPHILE ANTIBODY).

    Additional Manufacturer Narrative · 1

    DURING THE INVESTIGATION, THE FALSE NEGATIVE RESULTS WITH PHENYTOIN ON COBAS C501 AND THE HIGH RESULTS ON THE INTEGRA 800 WERE CONFIRMED WITH ALL SAMPLES. AS THE PATIENT SAMPLE INTERFERES WITH SEVERAL KINETIC INTERACTION OF MICROPARTICLES IN SOLUTION (KIMS) ASSAYS, WHICH INCLUDE DIFFERENT TYPES OF ANTIBODIES; IT IS CONCLUDED THAT THE PATIENT PRODUCED AN ANTIBODY AGAINST THE MICRO PARTICLE SURFACE. THE INTERFERENCE IS DOCUMENTED IN THE PRODUCT LABELING.

    Additional Manufacturer Narrative · 1

    THE INVESTIGATION HAS DETERMINED HAMA CAN BE EXCLUDED AS AN INTERFERENT IN THIS SAMPLE. IT WAS ALSO DETERMINED THAT AN INVESTIGATION INTO THE CROSS REACTIVITY POTENTIAL OF FEXOFENADIN (ALLEGRA) IS NOT REQUIRED AS THE EVENT WAS REPORTED TO BE LOW RECOVERY OF SAMPLES, AND NOT HIGH RECOVERY.

    Additional Manufacturer Narrative · 1

    IT WAS UNKNOWN IF THE INITIAL REPORTER SENT REPORT TO THE FDA. (B)(6).

    Description of Event or Problem · 1

    THE CUSTOMER RECEIVED QUESTIONABLE RESULTS FOR PHENYTOIN ON ONE PATIENT SAMPLE. THE ISSUE HAS BEEN ONGOING SINCE (B)(6) 2012. THE PHYSICIAN HAD REQUESTED THAT THE SAMPLE BE RUN ON AN INTEGRA 800. THE CUSTOMER BELIEVES THE PATIENT IN QUESTION HAS A HUMAN ANTI-MOUSE ANTIBODY WHICH IS CAUSING INTERFERENCE. ALL RESULTS ARE IN UG/ML. THIS MEDWATCH IS FOR TESTING DONE ON COBAS 6000 C501 SERIAL NUMBER (B)(4). THE ORIGINAL SAMPLE RESULT ON INTEGRA 800 SERIAL NUMBER (B)(4) WAS 20.0. THIS VALUE IS CONSIDERED TO BE THE CORRECT RESULT BY THE CUSTOMER AND WAS REPORTED OUTSIDE OF THE LABORATORY. THERE WAS NO ADVERSE EVENT. THE SAMPLE WAS THEN RUN ON A COBAS 6000 C501 (C501) SERIAL NUMBER (B)(4). THE RESULT GENERATED ON THE C501 WAS 2.6, ACCOMPANIED BY A DATA FLAG. THE SAMPLE WAS DILUTED WITH SALINE AND REPEATED ON THE SAME ANALYZER. THE REPEAT RESULT WAS 6.0. THE RESULTS GENERATED ON THE C501 WERE NOT REPORTED OUTSIDE OF THE LABORATORY. THERE WAS NO ADVERSE EVENT. THE CUSTOMER ALSO ALLEGED THAT THE DRUG ALLEGRA CROSS REACTED WITH THE PHENYTOIN ASSAY. THE CUSTOMER REFUSED A SERVICE DISPATCH FOR THIS ISSUE.

    Devices

    Seq Brand Generic Product Code Manufacturer Model Lot UDI-DI
    1 PHENYTOIN IMMUNOASSAY, DIPHENYLHYDANTION DIP ROCHE DIAGNOSTICS NA 65398001

    Patients

    Seq Age Sex Outcome Treatment
    1 054 YR TEGRATOL| DILANTIN| LYRICA| ALLEGRA| FINESTERIDE