ABSTRACT
The effect of ceftizoxime, a new aminothiazolil-syn-methoxy-iminocephalosporin has been evaluated on 169 strains of Gram negative bacilli isolated from hospitalized patients and compared with that of cefotaxime and of ceftriaxone. The effect of these 3 cephalosporins and of cefalotin was also evaluated on 50 strains of staphylococcus. CIM50 of ceftizoximel was as follows: K. pneumoniae less than .032, aureus and S. epidermidis less than .2 CIM90 for the same species was: K. pneumoniae less than .25, E. coli less than .63, E. Cloacae and S. marcescens less than 8, S. aureus less than 32, S. epidermidis less than 16. The values obtained with cefotaxime and ceftriaxone were similar. Cefalotin was clearly more active on staphylococcus strains with CIM50 and CIM90 for both species of less than .25 and less than .2 respectively.
Subject(s)
Ceftizoxime/pharmacology , Gram-Negative Bacteria/drug effects , Staphylococcus/drug effects , Cefotaxime/pharmacology , Ceftriaxone/pharmacology , Cephalothin/pharmacology , Drug Resistance, Microbial , Humans , In Vitro TechniquesABSTRACT
The effect of ceftizoxime, a new aminothiazolil-syn-methoxy-iminocephalosporin has been evaluated on 169 strains of Gram negative bacilli isolated from hospitalized patients and compared with that of cefotaxime and of ceftriaxone. The effect of these 3 cephalosporins and of cefalotin was also evaluated on 50 strains of staphylococcus. CIM50 of ceftizoximel was as follows: K. pneumoniae less than .032, aureus and S. epidermidis less than .2 CIM90 for the same species was: K. pneumoniae less than .25, E. coli less than .63, E. Cloacae and S. marcescens less than 8, S. aureus less than 32, S. epidermidis less than 16. The values obtained with cefotaxime and ceftriaxone were similar. Cefalotin was clearly more active on staphylococcus strains with CIM50 and CIM90 for both species of less than .25 and less than .2 respectively.
ABSTRACT
The sensitivity of microorganisms to antimicrobial preparations is determined--using agar as the test medium--by means of a semi-quantitative method involving two concentrations, i.e. a low concentration relating to serum levels easily attained at the commonly used dosage level of the various antibacterially acting preparations, and a high concentration corresponding to serum levels attainable at increased dosage via the appropriate route of administration. The inoculum is distributed with a multi-inoculator making a simultaneous inoculation of 25 strains possible. For 25 antibiograms with 20 antibiotics 40 Petri dishes are required, inoculation take 15 min. The method described is suited above all for laboratories with large workload where a great number of resistance determinations must be carried out rapidly, precisely at a low cost.
