RESUMO
Several research center have been set up to evaluate the system that deals with sensitivity to microbes under Sensititre break-point. The study has been broken down as follows: the break-point system was compared with the agar diffusion according to Bauer et al., using 1180 strains of fast-growing Gram-negative bacteria; a limited number of strains (176) have been used to compare the Sensititre break-point and the Sensititre MIC; results have been obtained testing 448 strains processed by break-point with correct inoculum and with simplified inoculum, from a colony; an investigation has been carried out on the time and cost of the break-point functioning. Having taken the Bauer system and others are compared them with the break-point, it was seen that their total agreement was 90.3% with 2% of major disagreement. The total major disagreement between Sensititre MIC and Sensititre break-point was 2.7%. The total major disagreement of the latter was largely the result of cephalotin (21%) on the Escherichia coli strains. An initial research centre has been formed to try to trow light upon the origins of such disagreements and we are now pleased to report back their initial findings. The preparation and reading of a test with the Bauer system and others takes about 18 minutes and costs 5600 Lit; a break-point test takes 10 minutes and costs 4500 Lit.