RESUMO
Xylose lysine deoxycholate (XLD) agar was more efficient for the detection of Shigella sonnei than Salmonella-Shigella (SS) agar and Drigalski agar, XLD was slightly more efficient for the detection of Salmonellae by direct plating than SS agar. Xylose lysine deoxycholate agar is proposed as the second selective plating medium for Shigellae isolation. It is also a useful second selecting plating medium for the isolation of Salmonellae serotypes, which form non-characteristic colonies on Bismuth-Sulfite agar. Efficiency comparisons between 4 direct plating media and one enrichment medium were made during the period of 3 years by analysing 21793 fresh clinical stool specimens. In that time 1394 Salmonella and 519 Shigella strains were isolated.
