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•As derived from API 20E (bioM6rfeux, inc.) for identification of Enterobacteriaceae.

Figure 7-18 Example erf converting a metabolic profile to an octal profile for bacterial identification.

updated taxonomic status of clinically relevant bacteria. Although microbiologists typically do not establish and maintain their own databases, an overview of the general approach provides background information.

The first step in developing a database is to accumulate many bacterial strains of the same species. Each strain is inoculated to an identical battery of metabolic tests to generate a positive-negative test profile. The cumulative results of each test are expressed as a percentage of each genus or spedes that possesses that chararteristic. For example, suppose that 100 different known E. coli strains and 100 known Shigella spp. strains are tested in four biochemicals, yielding the results illustrated in Table 7-2. In reality, many more strains and tests would be performed. However, the prindple—to generate a database for each spedes that contains the percentage probability for a positive result with each test in the battery—is the same.

Manufacturers develop databases for each of the identification systems they produce for diagnostic use {e.g., Enterobacteriaceae, gram-positive cocd, non-fermentative gram-negative bacilli). Because the data are based on organism "behavior'' in a particular commerdal system, the databases cannot and should

Table 7-2 Generation and Use of Genus-Identification Database Probability: Percent Positive Reactions for 100 Known Strains

Biochemical Parameter

Table 7-2 Generation and Use of Genus-Identification Database Probability: Percent Positive Reactions for 100 Known Strains

Biochemical Parameter

Organism

Lactase

Sucrose

Indole

Ornithine

Escherichia

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Bacterial Vaginosis Facts

Bacterial Vaginosis Facts

This fact sheet is designed to provide you with information on Bacterial Vaginosis. Bacterial vaginosis is an abnormal vaginal condition that is characterized by vaginal discharge and results from an overgrowth of atypical bacteria in the vagina.

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