The microbiologist uses TSI and LIA agars to rule out stool pathogens,Salmonella and Shigella spp.The reactions observed are TSI: K/A,H2S+ and LIA: R/A.What should the technologist do next?

Question

Quizplus · Accepted Answer

Although the hydrogen sulfide is usually suspicious of Salmonella the technologist would quickly look at the LIA: R/A and realize that this organism is lysine deaminase positive effectively eliminating both stool pathogens (both are lysine deaminase negative).The organism could possibly be a Proteus spp.(normal stool flora)and,as long as there are no other suspicious colonies,normal stool flora can be reported.

The Microbiologist Uses TSI and LIA Agars to Rule Out