[A new modification of Pizu's medium for the rapid identification of Corynebacterium diphtheriae based on the AGV medium].

Various nutrient bases (dry nutrient agar, erythrol agar, medium for toxigenicity determination, casein-yeast and AGV media) have been examined to choose a base for Pizu's medium instead of agar D that is no longer manufactured. AGV medium has been found the best nutrient base. The method for the preparation of Pizu's medium has been simplified. The modified Pizu's medium permits the detection of cystinase in C: diphtheriae in 3-5 hrs both in pure and mixed cultures.