Investigation: a potential false positive vibrio result on the biofire gi panel was reported after testing a patient stool sample in cary blair transport media on (b)(6) 2024.On (b)(6) 2024, the sample was tested again on the biofire gi panel, but was negative for vibrio.The customer stated that the patient was not affected due to the biofire gi panel result.No serious injury or death was reported.Conclusion: the investigation determined that the most likely cause of the discrepant vibrio result was the presence of non-viable organism/nucleic acid in the cary blair transport media.While cary blair medium vials are autoclaved and routinely quality controlled for sterility, non-viable organisms or nucleic acids can remain in the transport medium after the sterilization process.The presence of non-viable organisms and nucleic acid does not compromise the intended use of transport medium, transportation and preservation of clinical stool and rectal specimens; however, the biofire gi panel does not distinguish between nucleic acid from viable or non-viable organisms.The "laboratory precaution" and "limitation" sections of the filmarray gi reagent instruction booklet (https://www.Online-ifu.Com/iti0030) outlines the potential for false positive detections during molecular testing with sterile cary blair transport medium containing detectable levels of non-viable organisms and/or nucleic acid.Importantly, results from the biofire gi panel are intended to be correlated with the clinical history, epidemiological data, and other data available to the clinician evaluating the patient.Detection of organism targets does not imply that the corresponding organisms are infectious or are the causative agents for clinical symptoms.Clinical performance: according to table 11.Biofire gi clinical performance summary of the filmarray gi reagent instruction booklet, the performance claim for vibrio (v.Parahaemolyticus/v.Vulnificus/v.Cholerae) compared to stool culture with standard manual/automated microbiological/biochemical identification showed a specificity of 99.9% (95% ci 99.5-100%).Vibrio was detected in 2/2 false positive specimens using bi-directional sequence analysis.To supplement the results of the prospective clinical study, an evaluation of preselected archived specimens was performed.According to table 17.Biofrie gi panel archived specimen performance data summary, the performance claim for vibrio showed a positive percent agreement (ppa) of 100% (95% ci n/a) and a negative percent agreement (npa) of 100% (95% ci 97.1-100%).Additionally, in table 18.Biofire gi panel performance using contrived specimens, vibrio showed a ppa of 97.4% (95% ci 92.6-99.5%) and a npa of 100% (95% ci 94.0-100%).Includes 64/65 v.Cholerae (five different strains were used in spiking; one specimen spiked near the assay limit of detection was not detected) and 48/50 non-v.Cholerae (four v.Parahaemolyticus strains and one v.Vulnificus strain were used in spiking; two specimens spiked with v.Parahaemolyticus near the assay limit of detection were not detected).
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