A customer in (b)(6) reported the occurrence of false negative (no growth) for yeast from a vaginal specimen.Testing via alternate agar media (cpse, pvx, anc) obtained good growth.Identification testing (vitek® 2 yst id test kit) produced a result of "no identification." blastese test was positive; customer concluded candida albicans.Incubation time allowed by the customer = 48 hours.Instructions for use (ifu) indicate incubation up to 72 hours.Plates were stored at 4°c in a lighted environment.This practice is outside the ifu; the plates should be stored in a manner protected from light.Additionally, the ifu indicates "growth depends on the requirements of each individual microorganism.It is therefore possible that certain yeast strains which have specific requirements (substrate, temperature, etc.) may not grow or may not produce color." the customer stated no incorrect result was reported to the treating physician, and there was no adverse impact to the patient's state of health.Biomérieux internal investigation will be initiated.
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This report was initially submitted following notification that a customer in (b)(6) reported the occurrence of a false negative result (no growth) in association with the chromid® candida agar.Biomérieux investigation was conducted.The strain submitted by the customer was tested with the implicated lot and a random lot of chromid® candida agar.After 24 hours of incubation, growth of white colonies was obtained for both lots tested.At 48 hours of incubation, development of blue colonies was observed for both lots tested.As indicated in the package insert, the development of pale blue to dark blue colonies is characteristic of candida albicans.The biomérieux investigation did not reproduce the results obtained by the customer using the quality control strains and the strain submitted by the customer.Good growth of the customer's candida albicans patient strain was observed on all lot numbers tested.A review of the quality control certificate for lot number 1005462060 indicated that the product conformed with specifications for appearance, color, ph, microbiological activity and microbiological state.Laboratory quality controls conformed with specifications for microbiological activity for all quality controls tested; candida albicans atcc® 2091¿, candida albicans atcc® 10231¿, candida tropicalis atcc® 9968¿, proteus mirabilis atcc® 12453¿, enterococcus faecalis atcc® 29212¿.Laboratory quality controls conformed with specifications for microbiological state and appearance.167 plates were incubated at 20-25c and 170 plates were incubated at 33-37c.All plates conformed with specifications.There were no non-conformities or deviations associated with lot 1005462060.The investigation concluded the chromid® candida agar is performing as intended.
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