[Surveillance of susceptibility of clinical isolates to panipenem between 2000 and 2003].

For the post-marketing surveillance of panipenem/betamipron (PAPM/BP, Carbenin), MICs of injectable beta-lactam antibacterials including PAPM against clinical isolates from 15 medical institutions all over Japan are measured yearly and the incidence rates of resistance in various species are also evaluated. In the first surveillance from June 2000 to March 2001, 1,356 isolates of 28 species were tested, 1,221 isolates of the same 28 species were tested in the second surveillance from April 2001 to March 2002, and 1,403 isolates of the same 28 species were tested in the third surveillance from April 2002 to March 2003. No remarkable changes in the activity of PAPM were observed in these surveillances spanning three years. The activity of PAPM in this study was comparable to that in the studies conducted before Carbenin was launched. This result suggests that PAPM still maintains potent activity. In these surveillances spanning three years, the incidence rates of resistance in various species were as follows (2000.6-2001.3 --> 2001.4-2002.3 --> 2002.4-2003.3): methicillin-resistant Staphylococcus aureus (39.3% --> 43.9% --> 47.3%), penicillin-intermediate Streptococcus pneumoniae (48.9% --> 44.2% --> 25.7%), penicillin-resistant S. pneumoniae (PRSP, 13.8% --> 26.3% --> 43.2%), extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli (0.9% --> 0% --> 1.4%), ESBL-producing Klebsiella pneumoniae (3.4% --> 1.3% --> 3.1%), beta-lactamase-producing Haemophilus influenzae (19.2% --> 8.9% --> 42.9%), beta-lactamase-negative ampicillin-resistant H. influenzae (BLNAR, 22.1% --> 30.7% --> 33.0%), and metallo-beta-lactamase-producing Pseudomonas aeruginosa (1.0% --> 4.4% --> 1.0%). PAPM showed the most potent activity among tested drugs against PRSP, whose incidence rate increased notably. BLNAR, whose incidence rates also increased, exhibited low susceptibility to all tested drugs and metallo-beta-lactamase-producing P. aeruginosa also exhibited high resistance. The findings of this surveillance indicate that it is necessary to pay careful attention to the trends of resistant bacteria such as PRSP, BLNAR, and metallo-beta-lactamase producing strains.

[Surveillance of susceptibility of clinical isolates to cefpodoxime between 2000 and 2003].

For the post-marketing surveillance of cefpodoxime proxetil (CPDX-PR, Banan), MICs of oral cephem antibacterials including CPDX against clinical isolates from 15 medical institutions all over Japan are measured yearly and the incidence rates of resistance in various species are also evaluated. In the first surveillance from June 2000 to March 2001, 1,091 isolates of 22 species were tested, 993 isolates of the same 22 species were tested in the second surveillance from April 2001 to March 2002, and 1,115 isolates of the same 22 species were tested in the third surveillance from April 2002 to March 2003. No remarkable changes in the activity of CPDX were observed against most of the species in these surveillances spanning three years and in comparison with that in the studies conducted before Banan was launched. In the study, CPDX as well as other cephem antibacterials showed a gradual decrease in activity against all the strains of Streptococcus pneumoniae and Haemophilus influenzae in proportion to the increase in the incidence rates of penicillin-resistant S. pneumoniae (PRSP) and beta-lactamase-negative ampicillin-resistant H. influenzae (BLNAR). A small percentage of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae, which are high-resistant strains, were isolated. The findings of this surveillance indicate that it is necessary to pay careful attention to the trends of resistant bacteria such as PRSP, BLNAR, and ESBL-producing strains.

[Surveillance of susceptibility of clinical isolates to cefmetazole between 2000 and 2003].

For the post-marketing surveillance of cefmetazole (CMZ, Cefmetazon), MICs of injectable beta-lactam antibacterials including CMZ against clinical isolates from 15 medical institutions all over Japan are measured yearly and the incidence rates of resistance in various species are also evaluated. In the first surveillance from June 2000 to March 2001, 574 isolates of 13 species were tested, 548 isolates of the same 13 species were tested in the second surveillance from April 2001 to March 2002, and 654 isolates of the same 13 species were tested in the third surveillance from April 2002 to March 2003. No remarkable changes in the activity of CMZ were observed in these surveillances spanning three years. The activity of CMZ in this study was comparable to that in the studies conducted before Cefmetazon was launched. This result suggests that CMZ still maintains potent activity. Changes in percent resistance of each species to CMZ (MIC of CMZ > or = 32 microg/ml) were as follows: methicillin-susceptible Staphylococcus aureus (MSSA, 0.0% --> 0.0% --> 0.0%), methicillin-resistant Staphylococcus aureus (MRSA, 72.9% --> 87.2% --> 88.7%), Staphylococcus epidermidis (18.5% --> 31.6% --> 14.3%), coagulase-negative Staphylococcus spp. (CNS, 13.3% --> 18.2% --> 21.4%), Escherichia coli (3.6% --> 0.8% --> 2.1%), Klebsiella pneumoniae (3.4% --> 3.8% --> 2.1%), Klebsiella oxytoca (0.0% --> 0.0% --> 0.0%), Proteus mirabilis (2.3% --> 2.1% --> 0.0%), Proteus vulgaris (13.6% --> 6.7% --> 0.0%), Morganella morganii (7.3% --> 0.0% --> 14.0%), Providencia spp. (12.5% --> 0.0% --> 18.2%), Peptostreptococcus spp. (0.0% --> 0.0% --> 0.0%), Bacteroides fragilis (10.3% --> 10.8% --> 17.1%), Bacteroides spp. (78.6% --> 87.5% --> 62.5%). The Change in percent resistance of MRSA, other CNS, and B. flagiris tended to increase. It is necessary to pay much attention to trends observed in these species. Compared to other drugs tested, against MSSA, the activity of CMZ was inferior to that of CEZ, CTM, and FMOX and superior to that SBT/CPZ. Against MRSA, S. epidermidis, and CNS, the tested drugs exhibited little activity. Against Gram-negative bacteria, the activity of CMZ was almost superior to that of CEZ and CTM, and inferior to that of FMOX. Against B. flagiris and other Bacteroides spp., the activity of CMZ was almost superior to that of CEZ and CTM, and comparable to or inferior to that of SBT/CPZ and FMOX.

[Antibacterial activity of panipenem against clinical isolates in 2000 and 2001].

As the post-marketing surveillance of panipenem/betamipron (Carbenin), MICs of panipenem (PAPM) against 1355 clinical isolates of 28 species from 15 medical institutions all over Japan from June 2000 to March 2001 were measured using the broth microdilution method approved by the Japanese Society of Chemotherapy and compared with those of parenteral carbapenem antibacterials, imipenem (IPM) and meropenem (MEPM), and parenteral cephem antibacterials, cefozopran, cefepime, and sulbactam/cefoperazone. The activity of PAPM was comparable to that of IPM against almost all species tested. Compared with MEPM, PAPM was more active against Gram-positive bacteria and Bacteroides spp., and less active against Gram-negative bacteria. Compared with the parenteral cephems, PAPM was more active against most of species tested and its MIC ranges were narrower than those of the cephems as were those of other carbapenems. In this surveillance study, the incidence of resistance in various species were as follows: 39.3% for methicillin-resistant Staphylococcus aureus, 47.3% for penicillin-intermediate Streptococcus pneumoniae (PISP), 15.1% for penicillin-resistant S. pneumoniae (PRSP), 0.9% for extended-spectrum beta-lactamase (ESBL) producing Escherichia coli, 3.4% for ESBL producing Klebsiella pneumoniae, 19.2% for beta-lactamase producing Haemophilus influenzae, 24.0% for beta-lactamase-negative ampicillin-resistant (BLNAR) H. influenzae, and 1.0% for metallo-beta-lactamase producing Pseudomonas aeruginosa. Against these resistant strains, carbapenems including PAPM showed generally more potent activity than cephems. It was noted that PAPM showed the most potent activity against PISP and PRSP, which showed high incidence of 62.4% totally, among tested drugs. Metallo-beta-lactamase producing P. aeruginosa exhibited high resistance and BLNAR H. influenzae also exhibited low susceptibility against all tested drugs. But no remarkable change in the activity of PAPM against other species was observed in this study compared with that in the studies before the marketing of Carbenin. Furthermore, it is necessary to pay much attention to the trend of resistant strains such as PRSP, metallo-beta-lactamase producing bacteria, and BLNAR H. influenzae.

[Antibacterial activity of cefpodoxime against clinical isolates in 2000 and 2001].

As the post-marketing surveillance of cefpodoxime proxetil (Banan), MICs of cefpodoxime (CPDX, an active form of Banan) against 1090 clinical isolates of 22 species from 15 medical institutions all over Japan from June 2000 to March 2001 were measured using the broth microdilution method approved by the Japanese Society of Chemotherapy and compared with those of oral cephem antibacterials, cefaclor, cefdinir, cefditoren, and cefcapene. In this study, remarkable change in the activity of CPDX was observed in Streptococcus pneumoniae and Haemophilus influenzae compared with the susceptibility in the studies before Banan was launched. This cause is considered to be the increase in the incidence of the following resistant strains: penicillin-intermediate S. pneumoniae (47.3%), penicillin-resistant S. pneumoniae (PRSP, 15.1%), and beta-lactamase-negative ampicillin-resistant (BLNAR) H. influenzae (24.0%), which were scarcely isolated in 1989 when Banan was launched. Other tested drugs also exhibited low activity against these resistant strains. However, CPDX showed comparatively good activity with MIC90 of 2 micrograms/mL against PRSP. Against methicillin-susceptible Staphylococcus spp., Streptococcus pyogenes, Streptococcus agalactiae, and Moraxella catarrhalis, CPDX also showed comparatively good activity with MIC90 of < or = 4 micrograms/mL, which was almost equal to that in the studies before its marketing. Against quinolones-resistant Neisseria gonorrhoeae, CPDX showed excellent activity with MIC90 of 0.5 microgram/mL. Against members of the family Enterobacteriaceae except for Citrobacter freundii, Enterobacter spp., Proteus vulgaris, and Morganella morganii, CPDX showed good activity. However, in Escherichia coli, Klebsiella spp. Proteus spp., and Providencia spp., there are some high-resistant strains to all tested drugs including CPDX. Against Peptostreptococcus spp., MIC90 of CPDX was 8 micrograms/mL and its MIC range was widely distributed from 0.03 to 32 micrograms/mL, which were similar to those in the studies before its marketing. In this study, CPDX showed the decrease in the activity against several species as did other drugs tested, but against most of species tested, CPDX maintained good activity. Furthermore, it is necessary to pay much attention to the trend of resistant strains.