[Comparative study and time changes in the resistance to gentamycin, tobramycin, sisomicin and amikacin of Gram-negative nosocomial bacterial strains isolated from the urinary tract, in relation to the annual use of the aminoglycosides tested]. / Studio comparativo e variazioni nel tempo delle resistenze a gentamicina, tobramicina, sisomicina ed amikacina di ceppi batterici nosocomiali Gram-negativi isolati dalle vie urinarie, in relazione ai consumi ospedalieri annuali degli aminoglucosidi esaminati.

Changes in susceptibility to four aminoglycosides (gentamycin, amikacin, tobramycin, sisomicin) of bacterial strains, isolated from in-patients with urinary tract infections at the "Santa Maria della Scala" Hospital of Siena, in the period January-April in three consecutive years (1980, 1981, 1982) were studied. The change susceptibility patterns were related to the use of the four antimicrobial drugs in the same periods. Emergence of antibiotic-resistant strains was seen after a wider use, whereas an increasing number of susceptible strains was observed after reducing use of antimicrobial drugs.