RESUMEN
In the last few years, the use of chromogenic and fluorogenic reactions for the identification of the most important pathogens in human urinary tract infections has became a powerful tool in clinic diagnostic. The study was carry out in two hospitals in Havana City, comparing the performance of experimental medium with the traditional one: C.L.E.D. Medium produced by Centro Nacional de Biopreparados (BIOCEN). Additional biochemical test were applied (indole, motility, citrate, H2S glucose and lactose) for the more accurate identification of different strains. During the test 119 positive samples were evaluated with 82 identified as E. coli (68.9%). As coliforms 18 samples (15.1%) were identify without any biochemical test. The diagnostic sensitivity was 100% and diagnostic specificity of new medium was of 97.4% for all assayed samples.