[Further researches on antimicrobial agents involvement in urine bacteriological analysis (author's transl)].

A further investigation on about 2700 urine samples for testing the presence of antimicrobial drugs (spot-test) has been carried out. Bacteriostatic agents were present in 35% of all samples analysed, Of these, 47% were urines producing no growth on culturing, 10% had a bacterial count of 10(4) and 43% of 10(5) or more. The frequency of the spot-test positive samples was correlated to the origin from the different Hospital Departments. Gram-positive bacteria were the most represented in the samples without antimicrobial agents, while the frequency of Pseudomonas aeruginosa rised in samples with antimicrobial drugs. Under both conditions no significant variation in the antibiotic-sensitivity pattern was noted in organisms isolated from the urines. Only indole-positive Proteus appeared to be more sensitive when isolated from samples containing no antimicrobial agents.