Roche Susceptibility Test (RST) medium, a defined formulation for susceptibility testing: I. Nutrient interaction and optimization studies

Abstract Roche Susceptibility Test (RST) Medium represents the most completely optimized and convenient fully defined medium described. It requires no post-autoclaving supplementation with vitamins, supports good growth of all common aerobic and anaerobic pathogens and may be used as a broth or agar gel on which the swarming of Proteus spp. is virtually eliminated. The broth as a superior buffering capacity to most complex media and an osmolality and pH close to those of human serum. RST is highly satisfactory for the susceptibility testing of commonly used antibiotics and meets the requirements of the National Committe for Clinical Laboratory Standards of the U.S.A. in almost every respect.