MAUDE Adverse Event Report: CEPHEID XPERT MRSA/SA BC (US); XPERT MRSA/SA BLOOD CULTURE

Catalog Number	GXMRSA/SA-BC-10
Medical Device Problem Code	False Negative Result (1225)
Health Effect - Clinical Code	No Clinical Signs, Symptoms or Conditions (4582)
Date of Event	09/19/2025
Type of Reportable Event	Malfunction
Additional Manufacturer Narrative
This case highlights a questionable negative result for s.Aureus by xpert mrsa/sa bc, despite subsequent identification of mssa by maldi-tof ms and other methods.The discrepancies between xpert and the other identification methods employed suggests mutations or deletions in the spa gene which is the target used in the xpert mrsa/sa bc test to identify the presence of s.Aureus.Cepheid has attempted to reach the customer multiple times without success.The determination in this case is a false negative due to mutation/genetic drift.
Event or Problem Description
Customer reported discrepant results for sa when testing with xpert mrsa sa/bc and maldi-tof ms as well as other cultures.The customer stated the patient was symptomatic at time of sample collection, did not provide specific symptoms.Customer site procedure is to run maldi-tof ms for rapid identification on samples that do not produce sa positive result on xpert test.Customer site also stated bcid2 and phenotypic results of antimicrobial susceptibility testing indicated mssa.No patient harm was reported, however there was a delay in antimicrobial therapy.

• Brand Name: XPERT MRSA/SA BC (US)
• Common Device Name: XPERT MRSA/SA BLOOD CULTURE
• Manufacturer (Section D): CEPHEID; 904 e caribbean dr; sunnyvale CA 94089
• Manufacturer (Section G): CEPHEID; 904 e caribbean dr; sunnyvale CA 94089
• Manufacturer Contact: somesh lalithraj ; 904 e caribbean dr; sunnyvale, CA 94089 ; 4085488951
• MDR Report Key: 23319860
• Report Number: 3004530258-2025-00034
• Device Sequence Number: 4838671
• Product Code: NQX
• UDI-Device Identifier: 07332940000141
• UDI-Public: 07332940000141
• Combination Product (Y/N): N
• Initial Reporter State: PA
• Initial Reporter Country: US
• PMA/510(K) Number: K101879
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Serviced by Third Party (Y/N): N
• Reporter Type: Manufacturer
• Report Source: Health Professional,User Facility
• Initial Reporter Occupation: Administrator/Supervisor
• Type of Report: Initial
• Report Date (Section B): 10/16/2025

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Is this an Adverse Event Report?: No
• Is this a Product Problem Report?: Yes
• Operator of Device: Health Professional
• Device Expiration Date: 03/29/2026
• Device Catalogue Number: GXMRSA/SA-BC-10
• Device Lot Number: 1001452749
• Was Device Available for Evaluation?: No
• Type of Report(Section G): Thirty-Day
• Initial Date Received by Manufacturer: 09/23/2025
• Initial Report FDA Received Date: 10/16/2025
• Was Device Evaluated by Manufacturer? (Y/N): No
• Date Device Manufactured: 11/05/2024
• Is the Device Labeled for Single Use? (Y/N): Yes
• Is This a Single-Use Device that was Reprocessed and Reused on a Patient? (Y/N): No
• Usage of Device: Initial
• Patient Sequence Number: 1
• Patient Sex: Unknown