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Corynebacterium is a genus consisting of Gram-positive, rod-shaped bacteria, that is wildly distributed in nature. We report the epidemiological characterization of Corynebacterium spp. isolated from blood specimens at the Kurume University Hospital, between June 2008 and November 2011. Twenty-two strains that were likely Corynebacterium spp. were isolated from 22 hospitalized patients, of which 12 (54.5%) were identified as Corynebacterium striatum. Minimum inhibitory concentration tests were performed after biochemical and genotypic identifications. Biofilm production was detected using a 96-well microplate assay. The dissemination of C. striatum was investigated using pulsed-field gel electrophoresis (PFGE). All strains showed the tendency to be resistant to multiple drugs except vancomycin. Fourteen (82.4%) strains, including 9 C. striatum strains were capable of producing biofilms. Four distinct PFGE patterns were detected among C. striatum strains; 6 of which were identified as dominant pattern A (defined in this study) and had high biofilm production ability. During the 3-year monitoring period, these strains might have repeatedly infected the patients or could have readily colonized the hospital environments. C. striatum appeared to be a potential risk factor for bloodstream infections in hospitalized patients. More surveillance and enhanced control strategies are necessary to decrease Corynebacterium spp. infections in hospitals.

Corynebacterium is a genus consisting of Gram-positive, rod-shaped bacteria, that is wildly distributed in nature. We report the epidemiological characterization of Corynebacterium spp. isolated from blood specimens at the Kurume University Hospital, between June 2008 and November 2011. Twenty-two strains that were likely Corynebacterium spp. were isolated from 22 hospitalized patients, of which 12 (54.5%) were identified as Corynebacterium striatum. Minimum inhibitory concentration tests were performed after biochemical and genotypic identifications. Biofilm production was detected using a 96-well microplate assay. The dissemination of C. striatum was investigated using pulsed-field gel electrophoresis (PFGE). All strains showed the tendency to be resistant to multiple drugs except vancomycin. Fourteen (82.4%) strains, including 9 C. striatum strains were capable of producing biofilms. Four distinct PFGE patterns were detected among C. striatum strains; 6 of which were identified as dominant pattern A (defined in this study) and had high biofilm production ability. During the 3-year monitoring period, these strains might have repeatedly infected the patients or could have readily colonized the hospital environments. C. striatum appeared to be a potential risk factor for bloodstream infections in hospitalized patients. More surveillance and enhanced control strategies are necessary to decrease Corynebacterium spp. infections in hospitals.

Summary Background A vancomycin-intermediate Staphylococcus aureus (VISA) (vancomycin minimum inhibitory concentration: 4mg/L) outbreak occurred in an advanced emergency medical service centre [hereafter referred to as the intensive care unit (ICU)] between 2013 and 2014. Aim Our objective was to evaluate the infection control measures that were successful. Methods Seventeen VISA strains were isolated from the sputum of 15 inpatients and the skin of two inpatients. Fourteen VISA strains were recognized as colonization. However, three VISA strains were isolated from the sputum of three inpatients with pneumonia. Environmental cultures were performed and VISA strains were detected in five of 65 sites. Pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST) was performed on 21 VISA strains. Findings Molecular typing including PFGE and MLST showed that the patterns of 19 VISA strains were identical and those of the other two VISA strains were possibly related. This meant that a horizontal transmission of VISA strains had occurred in the ICU. In August 2013, the infection control team began interventions. However, new inpatients with VISA strains continued to appear. Therefore, in October 2013, the ICU was partially closed in order to try to prevent further horizontal transmission, and existing inpatients with the VISA strain were isolated. Although new cases quickly dissipated after the partial closure, it took approximately five months to eradicate the VISA outbreak. Conclusion Our data suggest that despite the employment of various other infection control measures, partial closure of the ICU was essential in terminating this VISA outbreak.

Prevention of candidemia has been difficult and empirical therapy may eventually reduce morbidity and mortality. Successful empirical therapies depend on understanding of fungal features and antifungal agents. Susceptibility to amphotericin B (AMPH-B), flucytosine (5-FC), fluconazole (FLCZ), itraconazole (ITCZ), miconazole (MCZ), and micafungin (MCFG) of 41 Candida species isolated from blood were determined. Candida albicans was the most common species (23 species), followed by C. parapsilosis (5 species), C. tropicalis (4 species), C. glabrata (3 species), C. guilliermondii (2 species), C. krusei (1 specie), and Candida spp (3 species). The isolation rates of the drug-resistant (DR) fungi were 5% for 5-FC. The rates of DR and susceptible dose dependent (S-DD) fungi were 0% and 2% for FLCZ, respectively. The rates of DR and S-DD fungi were 0% and 17% for ITCZ, respectively. No shift to resistant species in C. albicans occurred in our hospitals. All C. albicans were susceptible for the antifungal agents examined.

Cryptococcus neoformans and Cryptococcus gattii are the causative agents of cryptococcosis. Despite its importance, our knowledge of the epidemiology of cryptococcosis in Japan remains limited. To establish an epidemiological database on cryptococcosis in Japan, we determined the genetic variability of 44 Japanese clinical isolates of C. neoformans (var. grubii: serotype A) by multilocus sequence typing (MLST). The strains were clinically isolated from 1992 to 2011 in 5 different areas of Japan (the Hokkaido region [n = 1], Kanto region [n = 32], Chubu region [n = 1], Kansai region [n = 1], and Kyushu region [n = 9]). According to the method recommended by the International Society for Human and Animal Mycology cryptococcal genotyping working group, 36 isolates (82%) were identified as sequence type (ST)46. The remaining strains belonged to ST45 (n = 1) and ST47 (n = 1), and 6 isolates belonged to novel independent STs. There was little geographic difference in the ST population. Our present data are still limited; however, because most clinical isolates showed the same MLST profile in Japan, applying the current MLST scheme for Cryptococcus may at times be insufficient for investigating the infection route among outbreak cases. To solve this problem, it may be necessary to investigate other gene loci or develop a novel method with greater discriminatory power. However, in cases in which a strain belongs to a minor ST, our data may serve as useful epidemiological information in Japan.

We have recently detected Abiotrophia defectiva (A. defectiva) from postoperative blood culture of a patient with diffuse peritonitis. Pleomorphic Gram positive rod appearance and no growth on a standard sheep blood agar led us to suspect aerotolerant anaerobe. From the test results of simplified identification kit for anaerobes, we tentatively reported Clostridium tertium (C. tertium) to the clinician. However, the analysis of 16SrRNA sequence proved it to be A. defectiva. When Gram positive coccus or pleomorphic Gram positive rod are observed on blood culture, it is recommended to incubate Brucella HK (RS) blood agar plates for 24 hours at 35 degrees C both aerobically and anaerobically. The growth both aerobically and anaerobically suggests A. defectiva and Satellitism test and Rapid ID 32 STREP(SYSMEX) testing should be performed to identify the responsible bacteria. A. defectiva is Gram positive streptococcus and requires pyridoxal hydrochloride or L-cysteine to grow. It could be unidentified or misidentified and its particularity often leads incomplete report to the clinician. Our study shows that more careful examination will increase the detection of A. defectiva.

Hospital renovation projects pose risks of invasive infection by fungi from dust that is blown about during the period in question. Control measures to reduce the amount of dust during hospital renovation are thus necessary. Currently, no study has compared different control measures for effectiveness through more than one period of renovation. In this study, we examined the capacities of two control measures of weatherstripping (0.15 mm poly film and adhesive tape) to reduce the amount of blowing dust during two different hospital renovations (in 2008 and 2009). The amount of dust in the air of the hospital before and during the renovation was measured about once a week in both 2008 and 2009, and the between-year and within-year differences were tested. Our study revealed that the weatherstripping used in 2009 (adhesive tape) was significantly more effective than the measures taken in 2008 (0.15 mm poly film) to reduce the amount of dust during the renovations (p < 0.001), while in both years the amount of dust became significantly higher during the renovations than before the renovations. Differences in the effectiveness of weatherstripping during renovations between floors of the hospital were not significant in both 2008 and 2009. The number of Aspergillus-positive samples did not significantly increase compared with the number observed before the start of the hospital renovations (2006–2007) in 2008 and 2009, respectively. The weatherstripping potentially reduced the associated risk of airborne fungal infection.

The Ariake Sea area of Japan is endemic for Vibrio vulnificus infection. V vulnificus was isolated from slime from tidal flats, seawater, and fish Sea year-round as we reported previously. To identify new routes and factors of V vulnificus infection, we studied V. vulnificus pollution of imported frozen Black Tiger shrimps purchased from a fish market in Kurume, Fukuoka, Japan. V. vulnificus was isolated from 9 of 100 tails (9%) of Philippines products, 3 of 100 tails (3%) of Indonesia products, and 0 out of 100 tails (0%) of Madagascar products. Cytotoxin-hemolysin genes were identified in 7 V. vulnificus strains isolated from patients with V vulnificus septicemia, 9 strains from Philippine products, and 3 strains from Indonesian products. These results suggest that imported frozen Black Tiger shrimps are a new sources of V. vulnificus infection.