IN-VITRO ACTIVITY OF CEFPODOXIME AND 7 OT HER BETA-LACTAMS AGAINST 134 STRAINS OF HAEMOPHILUS-INFLUENZAE ISOLATED FROM OTITIS OR OTHER INFECTIONS, IN 1996

The in vitro activity of cefpodoxime and 7 other beta-lactams (amoxici llin : AMX, co-amoxiclav : AMC, cefaclor : CEF, cefotaxime : CTX, cefu roxime : CXM, cefixime : CFM, cefotiam : CTF) was determined against 5 7 ampicillin susceptible (S) strains of Haemophilus influenzae, 41 bet a-lactamase producing ampicillin-resistant (RBla+) strains of H. influ enzae, and 36 non beta-lactamase producing ampicillin-resistant (RBla- ) strains of H. influenzae. These strains were randomly selected eithe r among all strains isolated from acute otitis media in 1996 and colle cted at the ''National Reference Center on Haemophilus influenzae'', o r from other specimens collected in the last few years for 34 of the 3 6 RBla- strains. MICs 50 % of CPD, AMX, AMC, CEF, CTX, CXM, CFM, CTF w ere respectively : 0,03 - 1 - 0,5 - 0,5 - 0,007 - 0,5 - 0,03 - 0,5 mg/ l against S strains; 0,03 - 16 - 0,25 - 0,5 - 0,007 - 0,5 - 0,03 - 0,5 mg/l against RBla+ strains and 0,12 - 4 - 2 - 8 - 0,03 - 2 - 0,06 - 2 mg/l against RBla- strains. Cefotaxime, cefpodoxime, and cefixime had the best in vitro activity against S strains. The activity of beta-la ctams against RBla+ strains was unchanged, except for amoxicillin.The activity of cefotaxime, cefpodoxime, and cefixime against RBla- strain s was slightly reduced, but significantly reduced for the other beta-l actams and particularly for cefaclor.