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D.2.Additional medical device types: nsu, ouy, pqa.Investigation summary: the complaint investigation for discrepant results when using the bd max¿ vaginal panel (ref.443712), lot: 5262897 was performed by the review of manufacturing records, review of customer¿s data, retain material testing and by the complaint¿s history review.The customer reported a discrepant result for the trichomonas vaginalis (tv) target with bd max vaginal panel (ref#: 443712) kit, lot: 5262897.Two swabs were collected from the same patient and tested, one with the bd max vaginal panel assay and the other with the bd ctgctv2 for bd max¿ system (ref#: 443904) kit, lot: 5204477.The bd max vaginal panel assay gave a negative result for the tv target while the bd ctgctv2 assay gave a positive result.The customer provided runs files (pdf and csv) of runs (b)(4) from the instrument ct2473 for the investigation.Manual pcr curve adjudication was performed on the two samples.For the ctgctv2 run (b)(4), which was positive for tv, the amplification curve in the cy5 channel (tv target) showed a late amplification, consistent with a low positive sample.However, for the sample tested with the vaginal panel (run (b)(4), no amplification is seen in the fam channel (tv target) explaining the negative result, while the sample processing control target in the cy5.5 channel showed an expected amplification without anomaly, suggesting no issue with the test itself.These findings suggest that the target dna concentration in all the samples may have been at or near both assays limits of detection.Variability in target dna concentration between swabs from a same patient, combined with differences in assay sensitivity, may explain the discrepancies observed by the customer.Moreover, the intended use of each assay should be taken into consideration.According to their respective package inserts, the bd max¿ vaginal panel assay is indicated for vaginal swabs from symptomatic patients with vaginitis/vaginosis, whereas the bd ctgctv2 for bd max¿ system assay can be used with both symptomatic and asymptomatic individuals.Nevertheless, manual curve adjudication has limitations; visual examination of pcr curves for low signal is a conservative assessment of the data.The retain material of bd max¿ vaginal panel from lot: 5262897 was tested and the results were as expected.There is no indication of a reagent issue based on the analysis of the complaints received for discrepant results on bd max¿ vaginal panel lot: 5262897.Overall, based on the investigation, samples near the assay limit of detection combined with differences in assay design and intended use are the most likely causes to explain the customer¿s discrepant results.The root cause was not identified.Bd cannot confirm the complaint based on the investigation that was performed.Bd did not initiate a corrective and a preventive action plan since no new hazard identified.Bd apologizes for the inconvenience that this may have caused.
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