[Evaluation of the in vitro activity of aztreonam on 1990 gram-negative bacterial strains recently isolated in Campania hospitals].

The in vitro activity of aztreonam, leader of a new class of antibiotics, the monobactams, has been investigated. The effectiveness of the new molecule on 1990 strains of Gram-negative clinical isolates has been compared to that of some other drugs widely utilized for the treatment of nosocomial infections. Aztreonam has shown the highest activity against all the tested strains, with a geometrical mean of MICs (MG) of 0.37 and a MIC 90 of 8 micrograms/ml.