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A customer in the (b)(6) notified biomérieux of obtaining a low discrimination result while testing a salmonella abortusovis nctc qc strain using the api ®20 e 25strips (reference # 20100, lot #1007630390).The organism is a nctc (national collection of type cultures) strain of salmonella abortusovis.The result obtained with api 20 e strip was ¿low discrimination¿ with yersinia pestis (81.9%), e.Coli (8.9%) and shigella spp.(8,5%) as significant taxa and salmonella ser.Typhi (0.2%).Salmonella abortusovis is not included in api 20 e database.Per global customer service (gcs) and api experts, salmonella abortusovis was not tested during development; therefore, the identification is not possible for this strain and it's not possible to have an identification to the genus "salmonella spp".Salmonella spp.Is in the database but only applies to those species of salmonella which were tested when the database was created.Per the package insert, "api® systems identify an organism by using a methodology based on the characteristics of the data and knowledge about the organism and reactions being analyzed.Sufficient data have been collected from known strains to estimate the typical reactions of the claimed species to a set of discriminating biochemicals.If a unique identification pattern is not recognized, a list of possible organisms is given or the strain is determined to be outside the scope of the database.The software comment and/or the printed lab report contains suggestions for any supplementary tests necessary to complete the identification.If the tests are not sufficient to complete the identification, then standard microbiology references and literature should be consulted.Certain species may belong to a slashline (mixed) taxa.This occurs when the biopattern is the same for the taxa listed.Supplementary tests may be used to separate slashline taxa." there is no patient associated with this qc isolate; therefore, there is no adverse event related to any patient's state of health.A biomérieux internal investigation will be initiated.
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An investigation was initiated in response to a customer complaint of obtaining a low-discrimination result while testing a salmonella abortusovis nctc qc strain using the api® 20 e strip (reference # 20100, lot #1007630390).Complaint trend analysis complaint trending did not identify this issue as a trend for this lot or this product.Batch record analysis--- batch record analysis did not identify any issues associated with this lot.Quality control investigation quality control testing was performed on biomérieux retain samples of the customer's lot (1007630390) and a reference lot (1007865190).Strains tested: - proteus mirabilis atcc® 35659¿ cq 106 - enterobacter cloacae atcc 13047¿ cq 124 - escherichia coli atcc 25922¿ cq 126 - klebsiella pneumoniae ssp pneumoniae atcc 35657¿ / 13882 cq 112 - stenotrophomonas maltophilia atcc 51331¿ cq 219 results: all results are compliant with the profile for both lots, and there were no differences observed for the same strain between the two lots tested.Analysis of the strain the customer submitted their strain for investigational testing, but was unable to be used since the sample was provided as a lyophilized strain in an unsecured glass tube and the possibility of the presence of yersinia pestis could not be excluded.Instead, the strain salmonella enterica ssp enterica serotype abortusovis (nctc 10241) was ordered directly from nctc.The strain was analyzed by vitek® ms and the identification was confirmed to be salmonella enterica ssp enterica (99.9%).The strain was then tested with retain samples of the api® 20 e from the customer's lot (1007630390) and a reference lot (1007865190).Three (3) strips per lot were used for investigational testing.On apiweb¿, the interpretation is: low-discrimination between yersinia pestis (81.9%), escherichia coli 2 (8.9%), shigella spp (8.5%).The low-discrimination result is reproduced internally.In order to obtain a more discriminant identification between salmonella enterica ssp enterica and the other species, complementary tests were performed: nitrites (no2), nitrogen (n2), mobility (mob), growth on macconkey agar medium (mcc) and glucose oxidation/fermentation (of/o of/f).The final profile obtained gave a doubtful profile between yersinia pestis (61.1%), escherichia coli 2 (19.1%), pantoea spp1 (15.8%), salmonella ser typhi (3.6%).A doubtful result should not be taken into account as a final identification, and is not considered a misidentification.Comparing the profile obtained by the customer (and reproduced internally) with the expected profile for salmonella enterica ssp enterica, three (3) false negative reactions were identified.The false negative reactions for lysine decarboxylase (ldc), ornithine decarboxylase (odc), and rhamnose (rha) may contribute to the inaccurate detection of yersinia pestis (81.9%) instead of salmonella enterica ssp enterica.Conclusion no issues were identified with the manufacture of the customer's lot.Additionally, this issue was not identified as a trend for the customer's lot or the api® 20 e product.The customer's low-discrimination identification results were reproduced internally.However, a low-discrimination result has to be further investigated by completing additional tests.By completing the additional tests, the profile obtained leads to a doubtful profile in which the probability of yersinia pestis is reduced to 61.1%.Doubtful results should not be taken into account as a final identification and are not considered misidentifications.A change request has been opened to evaluate possible improvement of the database for the api® 20 e.
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