| Sumario: | Objectives: To investigate whether enrichment of clinical faecal specimens in Selenite F broth, for the cultivation of Salmonella and Shigella, should be discontinued in the community laboratory setting. Methods: A retrospective analysis of all faecal specimens submitted to Aotea Pathology Limited for bacterial culture over a two-year period was analysed using the Labsolutions statistics software. Samples positive for either Salmonella or Shigella were analysed as being isolated from either the direct Hektoen agar plate, isolated on secondary XLD agar plate following enrichment in Selenite F broth, or both. Results: Direct culture on Hektoen agar yielded a recovery rate of 39% of the Salmonella isolated and 67% of the Shigella isolated. Secondary sub culture on XLD agar following enrichment in Selenite F broth yielded a recovery rate of 99% of the Salmonella isolated and 50% of the Shigella isolated. Conclusions: This study shows that enrichment in Selenite F broth should continue to be used and a combination of direct plating and sub-culturing is required in order to maximise the recovery rate of both Salmonella and Shigella as well as to provide early detection. If enrichment was to be discontinued, potentially a significant proportion of Salmonella and Shigella isolates may have been missed (61% and 33% respectively).
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