Molecular typing of methicillin-resistant Staphylococcus aureus: Comparison of PCR-based open reading frame typing, multilocus sequence typing, and Staphylococcus protein A gene typing.

The recently developed PCR-based open reading frame typing (POT) method is a useful molecular typing tool. Here, we evaluated the performance of POT for molecular typing of methicillin-resistant Staphylococcus aureus (MRSA) isolates and compared its performance to those of multilocus sequence typing (MLST) and Staphylococcus protein A gene typing (spa typing). Thirty-seven MRSA isolates were collected between July 2012 and May 2015. MLST, spa typing, and POT were performed, and their discriminatory powers were evaluated using Simpson's index analysis. The MRSA isolates were classified into 11, 18, and 33 types by MLST, spa typing, and POT, respectively. The predominant strains identified by MLST, spa typing, and POT were ST8 and ST764, t002, and 93-191-127, respectively. The discriminatory power of MLST, spa typing, and POT was 0.853, 0.875, and 0.992, respectively, indicating that POT had the highest discriminatory power. Moreover, the results of MLST and spa were available after 2 days, whereas that of POT was available in 5 h. Furthermore, POT is rapid and easy to perform and interpret. Therefore, POT is a superior molecular typing tool for monitoring nosocomial transmission of MRSA.

Prevention of surgical site infection via antibiotic administration according to guidelines after gynecological surgery.

AIM: We modified the antimicrobial prophylaxis of surgical site infection (SSI) according to the guidelines of the Japanese Society of Chemotherapy and Japan Society of Infectious Diseases (hereinafter referred to as optimization) and measured outcomes. METHODS: From April 2016 to March 2017, we performed cesarean section and open hysterectomy with optimization, and compared the outcome to that of surgery performed without optimization between April 2014 and March 2016. We measured the rates of antibiotic discontinuation, appropriate antibiotic selection, SSI incidence, resumption of antibiotic therapy and fever incidence, as well as the length of postoperative hospital stay and medical expenses for antibiotics to evaluate the appropriateness and outcomes of antibiotic prophylaxis. RESULTS: Optimization resulted in a change in the method of selecting antibiotics for cesarean section, but there was no change in SSI incidence rate (0.74% vs 0.0%, P = 0.36). Optimization reduced the use of antibiotics and medical expenses of hysterectomy (median reduction of 50% and 78% for hysterectomy without or with lymphadenectomy, respectively). However, there was no change in outcome regarding SSI incidence (5.7% vs 0.0%, P = 0.11 and 7.8% vs 9.5%, P = 0.77, respectively). CONCLUSION: Appropriate use of antibiotics according to guidelines reduced antibiotic dose and medical expenses, but there was no change in outcome regarding SSI incidence rate. These findings suggested that implementation of dosing regimens according to the guidelines would be useful to reduce antibiotic medicine costs and prevent resistant bacteria and complications associated with antibiotics.

First report of KPC-2 Carbapenemase-producing Klebsiella pneumoniae in Japan.

We investigated a novel Japanese isolate of sequence type 11 (ST11), the Klebsiella pneumoniae carbapenemase-2 (KPC-2)-producing K. pneumoniae strain Kp3018, which was previously obtained from a patient treated at a Brazilian hospital. This strain was resistant to various antibiotic classes, including carbapenems, and harbored the gene blaKPC-2, which was present on the transferable plasmid of ca. 190 kb, in addition to the blaCTX-M-15 gene. Furthermore, the ca. 2.3-kb sequences (ISKpn8-blaKPC-2-ISKpn6-like), encompassing blaKPC-2, were found to be similar to those of K. pneumoniae strains from China.