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When creating or requesting concepts for the H antigen for Escherichia Coli O serogroup that cannot be typed, SNOMED International requests are declined due to ambiguity, but reporting of these organisms is necessary for Public Health reporting in Canada. SNOMED CT® Canadian CT Canadian Edition adds accommodates requests for public health reporting as needed.
Conventional Escherichia coli (E. coli) O:H serotyping is by agglutination of somatic (O) and flagellar (H) antigens with the use of E. Coli polyclonal antiserum. This is time-consuming, expensive, and available only in a small number of reference laboratories. When reporting the H antigen, it should be remembered that the O antigen is always present. In Canada, it is only a few that have reported it over the years Over the years, few in Canada have reported untyped or untype-able O antigens. For all organisms, the flagellar has to have the somatic (O).
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For E Coli where the O antigen is not typed or was unable to be typed, the guidance is to use E. coli serogroup O undetermined: H
Escherichia coli serogroup O undetermined: H (organism), indicate that the O is textual as undetermined as it is not known and untype-able
Example:
Escherichia coli serogroup O (organism)| Parent
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