[Evaluation of the BD Phoenix ID Yeast System for the Species Identification of Clinical Yeast-Like Organisms].

Most fungi isolated from patients with deep-seated mycosis are yeast-like organisms such as Candida and Cryptococcus. As their respective susceptibilities to antifungal agents can vary depending on the species, rapid identification is important for the administration of appropriate antifungal therapy. The aim of this study was to evaluate the performance of a new automated identification panel, Phoenix Yeast ID (Becton, Dickinson Diagnostics, USA) as well as the time required for identification. The identification results of 106 isolates generated by this system were then compared with those of the API 20C AUX system (SYSMEX bioMérieux Co., Ltd. Japan). Among the 106 isolates, the identification agreement between the two yeast panels was 97/106 (91.5%). Of the 9 (8.5%) discrepant identifications, 5 identification using the Phoenix Yeast ID system and 1 identification using the API 20C AUX system agreed with the genotypic identification. Genotypic identification did not agree with the Phoenix Yeast ID or API 20C AUX findings for the remaining 3 discrepant identifications. Approximately 60% of the C. albicans, C. tropicalis, and C. parapsilosis isolates were identified within 4 hours. In total, about 90% of the 4 major Candida sp. (C. albicans, C. tropicalis and C. glabrata) were identified within 8 hours. In conclusion, the Phoenix Yeast ID findings agreed well with the API 20C AUX findings. Genotypic identification of the discrepant identifications confirmed most of the Phoenix Yeast ID panel identifications. As approximately 80% of the major Candida sp. could be identified within 8 hours using the Phoenix Yeast ID identification system, our results suggest that this system is a clinically useful addition to commercially available yeast identification panels. The Phoenix Yeast ID system showed excellent concordance with genotypic identification for the classification of organisms with discrepant API 20C AUX findings.

In vitro activity of sitafloxacin against atypical bacteria (2009-2014) and comparison between susceptibility of clinical isolates in 2009 and 2012.

In vitro activities of sitafloxacin (STFX) along with fluoroquinolones (levofloxacin (LVFX), moxifloxacin (MFLX), garenoxacin (GRNX)) and macrolides (azithromycin, clarithromycin) against atypical bacteria (Mycoplasma pneumoniae, Legionella pneumophila, Chlamydia trachomatis, Chlamydophila pneumoniae) recovered from clinical specimens from 2009 to 2014 at different healthcare facilities in Japan were investigated. The minimum inhibitory concentration of STFX at which 90% of isolates (MIC90) against M pneumoniae (n= 14) was 0.03µg/mL which was comparable to GRNX, 4- and 16-fold more active than MFLX and LVFX, respectively. Reduced susceptibilities of M pneumoniae (9/14 isolates) to macrolides were observed. MIC90 of STFX against L. pneumophila (n =15) was 0.004µg/mL which was 2- and 4-fold more active than GRNX/LVFX and MFLX, respectively. The minimum inhibitory concentration range of STFX against C. trachomatis (n=5) and C. pneumoniae (n=5) were from 0.015 to 0.03 and from 0.03 to 0.06µg/mL, respectively. Furthermore, differences between the activities of STFX against various clinical isolates in 2009 and those in 2012, which were already published in two articles (Jpn. J. Antibiotics 63:411- 430, 2010, 66:311-330, 2013), were also evaluated. The MIC90s of STFX against methicillin- susceptible Staphylococcus aureus (MSSA), Streptococcus spp. and Enterococcus faecalis isolated in 2012 were 4 or 8 times higher than those in 2009, however there was no difference between STFX activities against other species in 2009 and those in 2012. In conclusion, STFX showed potent activity against atypical bacteria (M pneumoniae, L. pneumophila, C. trachomatis, C. pneumoniae) and no tendency for emergence resistance to Gram- positive cocci, Gram-negative bacteria and anaerobes except MSSA, Streptococcus spp. andt. faecalis.

[In vitro activity of sitafloxacin against clinical isolates in 2012].

In vitro activity of sitafloxacin (STFX) and various oral antimicrobial agents against bacterial isolates recovered from clinical specimens between January and December 2012, at different healthcare facilities in Japan was evaluated. A total of 1,620 isolates including aerobic and anaerobic organisms were available for the susceptibility testing using the microbroth dilution methods recommended by Clinical and Laboratory Standards Institute. The minimum inhibitory concentration of STFX at which 90% of isolates (MIC90) was 0.5 microg/mL for methicillin-susceptible Staphylococcus aureus and was 2 times lower than that of garenoxacin (GRNX), 4 times lower than that of moxifloxacin (MFLX), and 16 times lower than that of levofloxacin (LVFX). STFX inhibited the growth of all the isolates of Streptococcus pneumoniae at 0.06 microg/mL or less. The MIC90 of STFX was 0.03 microg/mL and was 2 times lower than that of GRNX, 4 times lower than that of MFLX, and 32 times lower than that of LVFX. Against Streptococcus pyogenes, the MIC90 of STFX was 0.06 microg/mL and was 2 times lower than that of GRNX, 8 times lower than that of MFLX, and 32 times lower than that of LVFX. The MIC90 of STFX was 2 microg/mL for Enterococcus faecalis, and was 4 times lower than that of GRNX, 8 times lower than that of MFLX, and 32 times lower than that of LVFX. The MIC90 of STFX for Escherichia coli was 2 microg/mL, and the MIC90(s) of other 10 species of Enterobacteriaceae which were the lowest values of the quinolones tested ranged from 0.03 to 1 microg/mL. The MIC90 of STFX for Pseudomonas aeruginosa isolates recovered from urinary infections was 4 microg/mL and was 32 times lower than those of GRNX, MFLX and LVFX. The MIC90 of STFX for P. aeruginosa isolates recovered from respiratory infections was 4 microg/mL and was 8 to 16 times lower than those of GRNX, MFLX, and LVFX. STFX inhibited the growth of all the isolates of Haemophilus influenzae at 0.004 microg/mL or less, and was 4 times lower than that of GRNX, 16 times lower than that of MFLX, and 8 times lower than that of LVFX. The MIC90 of STFX was 0.015 microg/mL for Moraxella catarrhalis, and was equal to that of GRNX, 4 times lower than those of MFLX and LVFX. The MIC90(s) of STFX ranged from 0.03 to 0.25 microg/mL for all the species of anaerobic bacteria and were the lowest values of all the antimicrobial agents tested. In conclusion, the activity of STFX against Gram-positive cocci was comparable or superior to those of GRNX, MFLX and LVFX. STFX showed the most potent activity against Gram-negative bacteria and anaerobic bacteria of all the antimicrobial agents tested in this study.

[Antimicrobial susceptibility surveillance of recent isolates from ophthalmological infections to gatifloxacin and other antimicrobial drugs].

The antimicrobial susceptibility of 240 isolates from the ophthalmological infections during July 2003 to March 2004 was determined to gatifloxacin (GFLX), levofloxacin, lomefloxacin and cefmenoxime applicable for ophthalmological infections. The in vitro activities of these drugs against the fresh isolates were compared. The quinolones including GFLX were potently active against Gram-positive bacteria, except for MRSA, a major causative pathogens for ophthalmological infection. When MIC ranges, MIC50 and MIC90 of three quinolones were compared, it was considered that the activity of GFLX was the most active of them. GFLX showed to be more active against opportunistic pathogens including Pseudomonas aeruginosa than other antimicrobial agents, and GFLX was especially potent against Streptococcus pneumoniae and Enterococcus faecalis. In conclusion, GFLX exhibits a potently active against fresh isolates from ophthalmological infections, and has an effective potential in the treatment of ophthalmological infections with the drug to administer eye drops.