MAUDE Adverse Event Report: The Binding Site Limited Optilite® Freelite® Lambda Free Kit

Model Number	LK018.OPT.A
Medical Device Problem Codes	High Test Results (2457); Low Test Results (2458)
Health Effect - Clinical Code	No Clinical Signs, Symptoms or Conditions (4582)
Date of Event	08/17/2026
Type of Reportable Event	Serious Injury
Event or Problem Description
The binding site were informed by the customer on (b)(6) 2026 that a falsely high lambda free light chain (flc) and a falsely low kappa free light chain (flc) patient results had been generated using the freelite® kappa free light chain assay (lk016.Opt.A) and freelite® lambda free light chain assay (lk018.Opt.A) on the optilite® analyser and released by the laboratory on (b)(6) 2026.The initial results were 2.3 mg/l for kappa flc and 19,722 mg/l for lambda flc.The discrepancy was identified when the results did not match the patient history.A redraw was tested on (b)(6) 2026 and produced results of 16 mg/l for kappa flc and 14.2 mg/l for lambda flc.Although no serious injury or change in patient management occurred, the incident is being reported as a precaution as the falsely high lambda flc result could potentially lead to serious injury if a similar issue were to recur and the result was considered in isolation.As stated in the ifus (ins016.Opt.A and ins018.Opt.A), free light chain measurement results should always be interpreted in conjunction with other laboratory and clinical findings.
Additional Manufacturer Narrative
To date, no assay or instrument performance issues have been identified.The investigation indicates that this is most likely a laboratory site-specific issue.

• Brand Name: Optilite® Freelite® Lambda Free Kit
• Common Device Name: Optilite® Freelite® Lambda Free Kit
• Manufacturer (Section D): The Binding Site Limited; 8 calthorpe road; edgbaston; birmingham, west midlands B15 1 QT; UK B15 1QT
• Manufacturer (Section G): The Binding Site Limited; 8 calthorpe road; edgbaston; birmingham, west midlands B15 1 QT; UK B15 1QT
• Manufacturer Contact: richard hughes ; 8 calthorpe road; edgbaston; birmingham, west midlands B15 1-QT ; UK B15 1QT
• MDR Report Key: 50772866
• Report Number: 9614373-2026-00007
• Device Sequence Number: 18747543
• Product Code: DEH
• UDI-Device Identifier: 05051700017800
• UDI-Public: 05051700017800
• Combination Product (Y/N): N
• Initial Reporter State: NY
• Initial Reporter Country: US
• PMA/510(K) Number: K231290
• 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: Other Health Care Professional
• Type of Report: Initial
• Report Date (Section B): 09/15/2026

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Is this an Adverse Event Report?: Yes
• Is this a Product Problem Report?: No
• Operator of Device: Health Professional
• Device Model Number: LK018.OPT.A
• Device Catalogue Number: LK018.OPT.A
• Device Lot Number: 551738
• 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: 08/20/2026
• Initial Report FDA Received Date: 09/15/2026
• Was Device Evaluated by Manufacturer? (Y/N): No
• 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: Initial
• Patient Sequence Number: 1
• Outcome Attributed to Adverse Event: Other
• Patient Sex: Unknown