Study of the in vitro activity of new cephalosporins on strains of Neisseria gonorrhoeae of the Toulouse region.

The study was carried out with 50 strains of gonococci. Susceptibility to the antibiotics was determined by standard sensitivity test, by systematic test for beta-lactamase and by measurement of the MICs. The cephalosporins tested were: moxalactam, cefotaxime, ceftriaxone, cefotiam, cefoxitin, cefazolin and cephalothin. Their activities were also compared with other beta-lactams, namely penicillin and ampicillin. The efficacy in vitro of the cephalosporins: in the lead, ceftriaxone, remarkably active, with cefotaxime following very close, and then moxalactam with cefotiam a little behind, and finally all the other beta-lactams tested. The median MICs of the new cephalosporins (moxalactam, cefotaxime, ceftriaxone and cefotiam) were at least 10 times greater than those of the other beta-lactams tested. The MIC values observed with a resistant strain (penicillin, ampicillin; MIC 256 microgram/ml) never exceed the maximum values found with the 50 susceptible strains.