EVALUATION OF UREASE AND BETA-GLUCOSIDASE ACTIVITY FOR THE PRACTICAL IDENTIFICATION OF MYCOBACTERIA

Use of urease and .beta.-glucosidase measurements for identification of mycobacteria was evaluated using 1019 strains received for reference purposes in 1978. The urease test was useful in the differential identification of BCG which, contrary to Mycobacterium bovis, gave a strong positive reaction in 3 h. The test was useful to discriminate M. scrofulaceum from pigmented strains of M. avium. The .beta.-glucosidase test discriminated between M. tuberculosis and M. bovis and was useful to distinguish the niacin-positive strains of M. africanum which were usally negative in this test. The .beta.-glucosidase test was particularly useful in differential identification of M. fortuitum and M. chelonei. The frequency distribution of the species submitted to the laboratory in 1978 was shown, and results obtained for each of the conventional test procedures were presented.