The nationwide surveillance of antibacterial susceptibility to meropenem (MEPM) and other parenteral antibiotics against clinical isolates during 2012 in Japan was conducted. A total of 2985 strains including 955 strains of Gram-positive bacteria, 1782 strains of Gram-negative bacteria, and 248 strains of anaerobic bacteria obtained from 31 medical institutions were examined. The results were as follows;

1. MEPM was more active than the other carbapenem antibiotics tested against Gram-negative bacteria, especially against enterobacteriaceae and Haemophilus influenzae MEPM was also active against most of the species tested in Gram-positive and anaerobic bacteria, except for multi-drug resistant strains including methicillin-resistant Staphylococcus aureus (MRSA).

2. Of all species tested, there were no species, which MIC₉₀ of MEPM was more than 4-fold higher than those in our previous studies in 2009 or 2006. Therefore, the tendency to increase in antimicrobial resistance rates was not observed.

3. MEPM resistance against Pseudomonas aeruginosa was 17.8% (56/315 strains). Compared to our previous results, it was the lowest than that in 2006 and 2009.

4. Carbapenem-resistant Klebsiella pneumoniae, and multi-drug-resistant Acinetobacter species, which emerged in worldwide, were not observed.

5. The proportion of extended-spectrum 𝛽-lactamase (ESBL) strains was 6.2% (59/951strains) in enterobacteriaceae, which increased compared with that of our previous studies in 2009 or before. Whereas, the proportion of metallo-𝛽-lactamase strains was 1.6% (5/315 strains) in P. aeruginosa, which was stable.

In conclusion, the results from this surveillance suggest that MEPM retains its potent and broad antibacterial activity and therefore is a clinically useful carbapenem for serious infections treatment at present, 17 years passed after available for commercial use in Japan.

Latamoxef (LMOX, Moxalactam) is one of the 𝛽-lactam antibiotics which is stable against 𝛽-lactamase. In this study, the antibacterial activity of LMOX was investigated, and Monte Carlo simulation was conducted to determine the appropriate dosing regimens of LMOX against extended-spectrum 𝛽-lactamase (ESBL) producing Enterobacteriaceae. The probability of target attainment (PTA) was analyzed at 40% and 70% of time above minimum inhibitory concentration (MIC) (time above MIC, T_>MIC) for bacteriostatic and bactericidal effect respectively. All the tested regimens achieved 85% of PTA at 40% of T_>MIC against ESBL producing Escherichia coli, and all the tested regimens except 1g q12h with 1 hour infusion achieved 85% of PTA at 40% of T_>MIC against ESBL producing Klebsiella pneumoniae. The effective regimens to achieve 85% of PTA at 70% of T_>MIC against E. coli were 1g q12h with 4 hours infusion, 1g q8h with 1–4 hours infusion, 2g q12h with 2–4 hours infusion, and 1g q6h with 1–4 hours infusion. The effective regimens to achieve 85% of PTA at 70% of T_>MIC against K. pneumoniae were 1g q8h with 3–4 hours infusion and 1g q6h with 1–4 hours infusion. These results of harmacokinetics/pharmacodynamics (PK/PD) modeling showed the potent efficacy of LMOX against bacterial infections caused by ESBL producing Enterobacteriaceae.

We investigated vancomycin-resistant genes for clinical isolates of 353 vancomycin-resistant enterococci in the Aichi Medical University hospital and 120 vancomycin-resistant enterococci from the 8 facilities in Aichi prefecture between April 2008 and January 2013. We detected 8, 105, 21 and 4 strains of enterococci with vanA, vanB, vanC1 and vanC2/C3, respectively. Among enterococci with vancomycin-resistant genes, we detected 4, 3 and 2 enterococci of vancomycin MIC level 4𝜇g/mL with vanB, vanC1 and vanC2/C3, respectively. According to molecular analysis using repetitive-sequence-based PCR (rep-PCR) for enterococci with vanA or vanB genes, although there have been no similarity for Enterococcus faecium with vanA and Enterococcus faecalis with vanB, high similarity was shown among E. faecium with vanB, which might be nosocomial spread in each hospital. These results showed that molecular analysis for vancomycin-resistant genes would be useful for the management of healthcare-associated infections.

Background: Many case series studies have reported risk factors of infection with anaerobic bacteria, but few factor analysis studies have been conducted.

Objective: We conducted a case–control study to identify the risk factors of anaerobic bacteremia.

Methods: We compared a number of characteristics of patients with anaerobic bacteremia with those with aerobic bacteremia. Clinical information for 71 patients of anaerobic bacteremia was collected from January 1999 to December 2012 in Aichi Medical University Hospital. For each case, we identified up to four controls matched by the time of the positive blood culture.

Results: Multivariate logistic analyses revealed an association between anaerobic bacteremia and malignancy (OR: 3.35, 95%CI: 1.85–6.09), Douglas’ pouch drains (OR: 25.90, 95%CI: 2.90–25.00) and chest drains (OR: 3.35, 95%CI: 1.19–9.43) as the primary causative disease, as well as associations between anaerobic bacteremia and the gastrointestinal tract (OR: 3.29, 95%CI: 1.38–7.81) , genitourinary tract (OR: 4.98, 95%CI: 2.06–12.05), Douglas’ pouch drains (OR: 16.95, 95%CI: 1.82–166.67) and chest drains (OR: 3.62, 95%CI: 1.29–10.20) as the primary causative organs. On the other hand, our study showed that having a central venous catheter was not associated with anaerobic bacteremia.

Conclusions: We demonstrated an association between anaerobic bacteremia and malignancy, gastrointestinal and genitourinary tracts, patients having a Douglas’ pouch drains or chest drains. These findings may be useful for developing early appropriate management for anaerobic bacteremia.