inforMED
MalfunctionJSO

BD BBL¿ CHROMAGAR¿ MRSA II 90MM

Received Oct 28, 2025 · Event occurred Oct 3, 2025

Report 9680577-2025-02919 · MDR key 23402959

Device

Generic name

Culture Media, Antimicrobial Susceptibility Test, Excluding Mueller Hinton

Catalog number

257435

Lot number

5223016

Product problems

  • Incorrect, Inadequate or Imprecise Result or Readings
  • Incorrect, Inadequate or Imprecise Result or Readings

Patient

NA · Unknown

  • No Clinical Signs, Symptoms or Conditions
  • No Clinical Signs, Symptoms or Conditions

Narrative

Additional Manufacturer Narrative

INVESTIGATION SUMMARY - THIS MEMO IS TO SUMMARIZE FINDINGS ON YOUR RECENT COMPLAINT PR (B)(4) AGAINST PLATE BBL CHROMAGAR MRSA II, CATALOG NUMBER 257435, LOT NUMBER 5223016 WITH RESPECT TO A PERFORMANCE ISSUE. EVENT DESCRIPTION: THE CUSTOMER HAS OBSERVED THAT IN FOUR INDIVIDUAL PATIENTS, THERE WAS A FALSE-POSITIVE MRSA RESULT ON THE CHROMAGAR MRSA. THESE ISOLATES SHOWED A TYPICAL PINK/PURPLE APPEARANCE AFTER INOCULATION, BUT SUSCEPTIBILITY TESTING REVEALED THAT THE STRAINS DID NOT EXHIBIT RESISTANCE. THE ISOLATES WERE RE-INOCULATED ON A DIFFERENT LOT OF CHROMAGAR MRSA, AND NO GROWTH WAS DETECTED THERE. COMPLAINT HISTORY REVIEW: THE COMPLAINT HISTORY OF THE LAST 12 MONTHS WAS REVIEWED, AND TWO OTHER PERFORMANCE COMPLAINTS WERE IDENTIFIED FOR THIS CATALOG NUMBER. A TREND WAS NOT IDENTIFIED. BATCH HISTORY RECORD (BHR) REVIEW: THE BATCH HISTORY RECORD WAS REVIEWED. NO DEVIATIONS FROM THE VALIDATED PROCESS PARAMETERS WERE DETECTED. RELEASE TESTING BY THE QC DEPARTMENT WAS SATISFACTORY. SAMPLE ANALYSIS: WITHIN THE COMPLAINT INVESTIGATION, RETAINMENT SAMPLES OF LOT 5223016 WERE ANALYZED ACCORDING TO THE QUALITY CONTROL RELEASE PARAMETERS USING STRAINS S. AUREUS MRSA ATCC 33592 AND S. AUREUS MRSA ATCC 43300. THE TESTED STRAINS GREW ACCORDING TO THE SPECIFICATION WITH MAUVE COLONIES, AFTER INCUBATION AEROBICALLY FOR 20-22 H AT 35-37 C. COLONY SIZE WAS ACCORDING TO THE SPECIFICATION. ADDITIONALLY, S. AUREUS MSSA ATCC 25923; S. AUREUS MSSA ATCC 29213 AND S. AUREUS MSSA ATCC 43387 WERE ANALYZED ACCORDING TO THE QUALITY CONTROL RELEASE PARAMETERS; THE TESTED STRAINS SHOWED COMPLETE INHIBITION ACCORDING TO THE SPECIFICATION, AFTER INCUBATION AEROBICALLY FOR 42-48 H AT 35-37 C IN THE DARK. RETURN SAMPLES WERE NOT PROVIDED BY THE CUSTOMER. PICTURE SAMPLES, PROVIDED BY THE CUSTOMER, SHOW PLATES OF LOT 5223016 WITH GROWTH OF LARGE DARK VIOLET COLONIES. ADDITIONALLY, PLATES OF LOT 5231080 SHOWED NO GROWTH. EVALUATION RESULTS: AT THIS STAGE OF OUR INVESTIGATION, WE HAVE EXCLUDED ANY SYSTEMIC FAILURE IN OUR PRODUCTION PROCESS. NO DEVIATION COULD BE FOUND DURING THE QC RELEASE PERFORMANCE TEST AND THE PERFORMANCE TEST ON THE RETAIN SAMPLES. DUE TO THE INDIVIDUAL GROWTH REQUIREMENTS OF THE DIFFERENT STRAINS, VARIABILITY CAN BE EXPECTED TO SOME EXTEND WHEN COMPARING MEDIA. OFTEN THE SENSITIVITY AND SPECIFICITY OF THE MEDIA ARE HIGHLY DEPENDENT ON THE INDIVIDUAL STRAINS TESTED ¿ WHICH EXPLAINS VARYING RESULTS WITHIN PUBLICATIONS REGARDING PERFORMANCE OF CHROMOGENIC MEDIA. INVESTIGATION CONCLUSION: BASED UPON OUR INVESTIGATION ON RETAIN SAMPLES OF THE COMPLAINT BATCH, THE COMPLAINT CANNOT BE CONFIRMED FOR A PERFORMANCE ISSUE. ALL TWO TESTED STAPHYLOCOCCUS AUREUS MRSA STRAINS SHOWED GROWTH ON THE TESTED PLATES. AND ALL THREE TESTED STAPHYLOCOCCUS AUREUS MSSA STRAINS SHOWED COMPLETE INHIBITION ACCORDING TO THE SPECIFICATION.

Description of Event or Problem

REPORT 2 OF 4: IT WAS REPORTED WHILE USING ONE (1) BD BBL¿ CHROMAGAR¿ MRSA II 90MM PLATE, A POSITIVE RESULT WAS OBTAINED FROM A PATIENT SAMPLE. AFTER THE PATIENT WAS PUT INTO ISOLATION, SUSCEPTIBILITY TESTING CONFIRMED IT WAS A FALSE POSITIVE RESULT. THERE WAS NO ADVERSE PATIENT IMPACT REPORTED.