Comparative Efficiency of Endo, Lithium Chloride Endo, Desoxycholate-Citrate, and Bismuth Sulfite Media for the Isolation of Eberthella Typhosa

Abstract

A rept. of the comparative efficiency of different culture media for the isolation of Eberthella typhosa from routine feces specimens received by the Laboratories of the Mississippi State Board of Health. The specimens are collected in 30% glycerol soln. (in 0.85% soln.) with emphasis on the amt. of specimen placed in the soln. (not to exceed 1 g.) and age of specimen (not more than 48 hrs. old from time of collection) until it reaches the laboratory. The laboratory technique employed is streaking the specimens the day they arrive, placing them at 20[degree] C refrigeration and replating them for 2 additional days. LiCl Endo is superior to plain Endo medium (both Difco and that prepd. by the Mississippi State Laboratories) based on a comparison of 477 positive isolations. Of the 724 positive cultures plated on LiCl Endo, desoxycholate-citrate, and bismuth sulfite there were 535 (74%) isolations on LiCl, 591 (82%) on desoxycholate-citrate, and 601 (83%) on bismuth sulfite. 195 specimens were positive only on one of the 3 media, 42 on LiCl Endo, 65 on desoxycholate-citrate and 88 on bismuth sulfite. Streaking the specimens 3 days appears an important factor when the additional number of positives obtained on the 2d and 3d days were 127 (24%) on LiCl Endo, 144 (24%) on desoxycholate-citrate, and 246 (40%) on bismuth sulfite, which would have been reported negative if only one day''s plating had been made.