MAUDE Adverse Event Report: Tosoh Hi-Tec, Inc. AIA-360; Fluorometer, For Clinical Use

Model Number	AIA-360 IMMUNOASSAY ANALYZER
Medical Device Problem Code	Incorrect, Inadequate or Imprecise Result or Readings (1535)
Health Effect - Clinical Code	No Clinical Signs, Symptoms or Conditions (4582)
Date of Event	08/31/2026
Type of Reportable Event	Malfunction
Event or Problem Description
A customer reported failing american proficiency testing (api) second event chemistry core proficiency testing for cardiac troponin i (ctnl2) sample cm-09 and creatine kinase mb (ck-mb) samples cm-07, cm-08, and cm-09 on the aia-360 analyzer.The customer stated the testing was performed on (b)(6)2026, however, tosoh was not notified of the failed api testing until 31aug2026.Technical support specialist (tss) reviewed the customer's calibration and quality control data, with no issues found.Periodic maintenance (pm) was performed on 05jun2026 after the api failure.After the pm, the aia-360 analyzer was confirmed to operate as expected.The customer retested api in (b)(6)2026, and all result passed.The tosoh quality assurance (qa) lab passed all samples for api testing.No further action required by technical support specialist.There was no indication of any patient intervention or adverse health consequences due to the reported event.
Additional Manufacturer Narrative
A 13 month complaint history review and service history review for similar complaints was performed for the failure mode "api failure for cardiac troponin i (ctnl2) and creatine kinase mb (ck-mb)" on the aia-360 analyzer from 31jul2025 through aware date 31aug2026.There were no similar complaints identified during the searched period.The analyte application manual (aam) for cardiac troponin states the following: evaluation of results.Quality control.In order to monitor and evaluate the precision of the analytical performance, it is recommended that commercially available control samples be assayed daily.The minimum recommendations for the frequency of running internal control material are: ¿ after calibration, two levels of controls are run in order to accept the calibration curve.¿ the two levels of controls are also repeated after calibration when certain service procedures are performed (e.G.Temperature adjustment, sampling mechanism changes, maintenance of the wash probe or detector lamp adjustment or change).After daily maintenance, at least two levels of the control should be run in order to verify the overall performance of the tosoh aia system analyzers.If one or more control sample value(s) is out of the acceptable range, it will be necessary to investigate the validity of the calibration curve and the assay results before reporting patient values.Standard laboratory procedures should be followed in accordance with the regulatory agency under which the laboratory operates.Limitations of the procedure: for diagnostic purposes, the results obtained from this assay should be used in conjunction with other data (e.G., symptoms, results of other tests, clinical impressions, therapy, etc.).Troponin i results should never be used as the single determining factor in treatment of the patient.Physicians should be made aware that published literature indicates possible interference in troponin i assays - i.E.Both false positive and false negative results.16, 17 studies on patients diagnosed with myocarditis and dilated cardiomyopathy indicate that disease specific cardiac autoantibodies may be present in the serum and plasma of these and other patients.18-20 autoantibodies are generated against cardiac proteins and this could potentially cause false negative results if the autoantibodies produced interfere with the epitopes utilized in a particular manufacturer's assay.Patient samples may also contain human anti-mouse antibody (hama) due to either natural antibody production or antibodies produced in response to therapy regimens.Hama may cause either false positive or false negative results in assays using mouse monoclonal antibodies.Other heterophile antibodies are also known to interfere in assays of this type.St aia-pack ctni 2nd-gen has been designed to minimize the effects of heterophile antibodies, but interference from high titers cannot be ruled out.Results from this or any other in vitro diagnostic procedure which do not correlate with the clinical presentation of the patient should be interpreted with extreme caution.The use of a single ctni result on a patient should be discouraged.As with the other cardiac markers, a temporal pattern of rise and fall over time should be observed to aid in accurate interpretation of the results.Users are reminded that elevations in ctni can occur for reasons other than myocardial infarction, and lack of a ctni value over a certain value does not preclude ami or serious cardiac injury.Assays from various manufacturers may yield different results.Reactivity of the epitopes used in the assay vary with the form of ctni present in a specific specimen.Also, assay calibration between manufacturers is not standardized.Using st aia-pack ctni 2nd-gen, the highest concentration of troponin i measurable without dilution is approximately 115 ng/ml, and the lowest measurable concentration is 0.06 ng/ml (assay sensitivity).Although the approximate value of the highest calibrator is 115 ng/ml, the exact concentration may be slightly different.The assay specification, assay range high, should be defined as the upper limit of the assay range, 115 ng/ml.Although hemolysis has an insignificant effect on the assay, hemolyzed samples may indicate mistreatment of a specimen prior to assay and results should be interpreted with caution.Lipemia has an insignificant effect on the assay except in the case of gross lipemia where spatial interference may occur.Samples containing fibrin may exhibit either falsely elevated or falsely decreased results.Fibrin must be eliminated in the sample before assay begins.No patients with skeletal muscle disorders were studied.Certain medications may interfere with assay performance.Specimens from patients taking medicines and/or medical treatment may show erroneous results.All results should be interpreted with respect to the clinical picture of the patient.The analyte applicate manual (aam) for creatine kinase mb states the following: evaluation of results.Quality control.In order to monitor and evaluate the precision of the analytical performance, it is recommended that commercially available control samples be assayed daily.The minimum recommendations for the frequency of running internal control material are: ¿ after calibration, two levels of controls are run in order to accept the calibration curve.¿ the two levels of controls are also repeated after calibration when certain service procedures are performed (e.G.Temperature adjustment, sampling mechanism changes, maintenance of the wash probe or detector lamp adjustment or change).After daily maintenance, at least two levels of the control should be run in order to verify the overall performance of the tosoh aia system analyzers.If one or more control sample value(s) is out of the acceptable range, it will be necessary to investigate the validity of the calibration curve before reporting patient results.Standard laboratory procedures should be followed in accordance with the regulatory agency under which the laboratory operates.Limitations of the procedure: for diagnostic purposes, the results obtained from this assay should be used in conjunction with other data (e.G., symptoms, results of other tests, clinical impressions, therapy, etc.).Using st aia-pack ck-mb, the highest concentration of creatine kinase mb isoenzyme measurable without dilution is approximately 500 ng/ml, and the lowest measurable concentration is 0.5 ng/ml (assay sensitivity).The exact linearity of the st aia-pack ck-mb depends on the particular lot of calibrator in use.Although the approximate value of the highest calibrator is 500 ng/ml, the exact concentration may be slightly different.The assay specification, assay range high, should be defined as the upper limit of the assay range, 500 ng/ml.Although hemolysis has an insignificant effect on the assay, hemolyzed samples may indicate mistreatment of a specimen prior to assay and results should be interpreted with caution.Lipemia has an insignificant effect on the assay except in the case of gross lipemia where spatial interference may occur.Specimens from patients who have received preparations of mouse monoclonal antibodies for diagnosis or therapy may contain human anti-mouse antibodies (hama).Such specimens may show falsely elevated values when tested for ck-mb.Certain medications may interfere with assay performance.Specimens from patients taking medicines and/or medical treatment may show erroneous results.All results should be interpreted with respect to the clinical picture of the patient.The most probable cause of the reported event was traced to maintenance.

• Brand Name: AIA-360
• Common Device Name: Fluorometer, For Clinical Use
• Manufacturer (Section D): Tosoh Hi-Tec, Inc.; 1-37, fukugawa minami-machi; shunan, yamaguchi 74600 42; JA 7460042
• Manufacturer (Section G): Tosoh Hi-Tec, Inc.; 1-37, fukugawa minami-machi; shunan, yamaguchi 74600 42; JA 7460042
• Manufacturer Contact: janefrances ajiduah ; 2-2-1 yaesu; chuo-ku, tokyo 10400-28 ; JA 1040028 ; +1(650)636-8314
• MDR Report Key: 50947422
• Report Number: 3004529019-2026-00144
• Device Sequence Number: 9552103
• Product Code: KHO
• UDI-Device Identifier: 04560189282896
• UDI-Public: 04560189282896
• Combination Product (Y/N): N
• Initial Reporter State: KS
• Initial Reporter Country: US
• PMA/510(K) Number: K971103
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Serviced by Third Party (Y/N): N
• Reporter Type: Manufacturer
• Report Source: Health Professional
• Initial Reporter Occupation: Other Health Care Professional
• Type of Report: Initial
• Report Date (Section B): 09/30/2026

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 Model Number: AIA-360 IMMUNOASSAY ANALYZER
• Device Catalogue Number: 019945
• Device Lot Number: na
• Was Device Available for Evaluation?: Yes
• Is the Reporter a Health Professional?: Yes
• Type of Report(Section G): Thirty-Day
• Initial Date Received by Manufacturer: 08/31/2026
• Initial Report FDA Received Date: 09/30/2026
• Was Device Evaluated by Manufacturer? (Y/N): No
• Date Device Manufactured: 01/01/2021
• 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: Reuse
• Patient Sequence Number: 1
• Patient Sex: Unknown