MAUDE Adverse Event Report: INSTRUMENTATION LABORATORY CO. HEMOSIL HIT-AB (PF4-H); PLATELET FACTOR 4 RADIOIMMUNOASSAY

Catalog Number	00020014600
Medical Device Problem Codes	False Negative Result (1225); Adverse Event Without Identified Device or Use Problem (2993)
Health Effect - Clinical Code	Insufficient Information (4580)
Date of Event	05/20/2025
Type of Reportable Event	Malfunction
Additional Manufacturer Narrative
This is an initial report.A follow-up report will be submitted upon completion of the investigation.
Event or Problem Description
A complaint was filed on may 20, 2025 regarding a discrepant hit test result.The patient's hit results on the acl top instrument returned a negative result, but a follow-up sra conducted at an external facility on yielded a positive result.The instrument was calibrated on (b)(6) 2025.Due to clinical suspicion, the patient was initially treated with an alternative anticoagulant, briefly switched back to heparin, and then resumed appropriate therapy (bivalirudin and later apixaban) upon receiving the positive sra.The original serum sample has been discarded, and no elisa testing was performed.No known patient impact was reported.
Additional Manufacturer Narrative
Internal investigation included review of qc, calibration, and manufacturing records for reagent lot b36907, and service history for the acl top instrument.All controls were within range, calibration was properly performed, and no instrument issues were identified.The affected patient sample was not available for retesting.Internal testing of retained and alternate reagent lots with qc controls and panel samples showed all results within expectations.No root cause was identified.As per the product ifu, discrepancies with confirmatory tests like sra may occur, and functional assay confirmation is recommended in the clinical context.Based on this review, no problem was identified and no remedial action is required.This issue will be tracked through trend analysis.

• Brand Name: HEMOSIL HIT-AB (PF4-H)
• Common Device Name: PLATELET FACTOR 4 RADIOIMMUNOASSAY
• Manufacturer (Section D): INSTRUMENTATION LABORATORY CO.; 180 hartwell road; bedford MA 01730 2443
• Manufacturer (Section G): INSTRUMENTATION LABORATORY CO.; 180 hartwell road; bedford MA 01730 2443
• Manufacturer Contact: anuja khan ; 180 hartwell road; bedford, MA 01730 ; 7818614451
• MDR Report Key: 22284252
• Report Number: 1217183-2025-00035
• Device Sequence Number: 8467708
• Product Code: LCO
• UDI-Device Identifier: 08426950975380
• UDI-Public: (01)08426950975380(11)241119(17)260430(10)B37250
• Combination Product (Y/N): N
• Initial Reporter State: FL
• Initial Reporter Country: US
• PMA/510(K) Number: K153137
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Serviced by Third Party (Y/N): Unknown
• Reporter Type: Manufacturer
• Report Source: Health Professional
• Initial Reporter Occupation: Other Health Care Professional
• Type of Report: Initial,Followup
• Report Date (Section B): 07/24/2025

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
• Device Expiration Date: 04/30/2026
• Device Catalogue Number: 00020014600
• Device Lot Number: B37250
• Was Device Available for Evaluation?: No
• Is the Reporter a Health Professional?: Yes
• Type of Report(Section G): Thirty-Day
• Initial Date Received by Manufacturer: 05/20/2025
• Supplement Date Received by Manufacturer: Not provided
• Initial Report FDA Received Date: 06/18/2025
• Supplement Report FDA Received Date: 07/24/2025
• Was Device Evaluated by Manufacturer? (Y/N): Yes
• Date Device Manufactured: 11/19/2024
• Is the Device Labeled for Single Use? (Y/N): No
• Is This a Single-Use Device that was Reprocessed and Reused on a Patient? (Y/N): No
• Usage of Device: Unknown
• Patient Sequence Number: 1
• Patient Sex: Unknown