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Miwa Katagiri,1,2 Makoto Kuroda,2 Tsuyoshi Sekizuka,2 Norihide Nakada,3 Yukitaka Ito,4 Masanobu Otsuka,4 Manabu Watanabe,1 Shinya Kusachi1 1Department of Surgery, Toho University Ohashi Medical Center, Meguro-ku, Tokyo, Japan; 2Laboratory of Bacterial Genomics, Pathogen Genomics Center, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan; 3Research Center for Environmental Quality Management, Graduate School of Engineering, Kyoto University, Otsu-shi, Shiga, Japan; 4Division of Clinical Microbiology Laboratory, Toho University Ohashi Medical Center, Meguro-ku, Tokyo, JapanCorrespondence: Miwa KatagiriDepartment of Surgery, Toho University Ohashi Medical Center, 2-22-36 Ohashi, Meguro-ku, Tokyo, 153-8515, JapanTel +81354333086Fax +81354333091Email girioyoshikazu0513@gmail.comMakoto KurodaLaboratory of Bacterial Genomics, Pathogen Genomics Center, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo, 162-8640, JapanTel +81352851111Fax +81352851150Email makokuro@niid.go.jpBackground: Excrement containing antimicrobial-resistant bacteria (ARB) is discharged from the hospital sewage through wastewater treatment plants (WWTP) into rivers, increasing the antimicrobial resistance (AMR) burden on the environment.Purpose: We illustrate the contamination of hospital sewage tanks with ARB harboring antimicrobial resistance genes (ARGs) using comprehensive metagenomic sequencing. During the study period, we moved to a new hospital building constructed for renovation. Therefore, we investigated the difference in bacterial flora in the sewage tanks for each building with different departments, and the change in bacterial flora over time in new sewage tanks. Furthermore, we performed a comparative genome analysis of extended spectrum β-lactamase (ESBL)-producing organisms (EPOs) from hospital sewage and clinical samples. Residual antibiotics in the sewage tank were also measured.Methods: Metagenomic analysis was performed on the hospital sewage samples, followed by whole genome sequencing of EPOs.Results: The bacterial composition of new sewage tanks was comparable with that of old tanks within 1 month after relocation and was instantly affected by excrement. The bacterial composition of sewage tanks in the old and new buildings, containing rooms where seriously ill patients were treated, was similar. Selection on CHROMagar ESBL allowed detection of EPOs harboring blaCTX-M and carbapenemase genes in all sewage tanks. One of the sewage Escherichia coli strain comprising ST393 harboring blaCTX-M-27 corresponded to the clinical isolates based on core genome analysis. Moreover, the levels of levofloxacin and clarithromycin in the hospital sewage were 0.0325 and 0.0135 μg/mL, respectively.Conclusion: Hospital sewage was contaminated with many ARB species, ARGs and residual antibiotics, which can cause a burden on WWTP sewage treatment. The bacterial flora in the sewage tank was rapidly affected, especially by the ward with seriously ill patients. AMR monitoring of hospital sewage may help detect carriers prior to nosocomial ARB-associated outbreaks and control the outbreaks.Keywords: hospital sewage, antimicrobial resistance, antimicrobial resistance gene, metagenome analysis, whole genome sequencing, residual antimicrobial reagents

Background Elastomeric pumps (EPs) are devices that allow quantitative and continuous drug administration without the need for electronic control, and they are used by being filled with anticancer agents. Although the package inserts of several manufacturers that provide EPs describe the relationship between the flow rate per unit time and temperature, the solution is only saline solution or 5% glucose solution, and data on anticancer drugs have not been published. In this study, we focused on 5-fluorouracil (5-FU), a drug frequently used in cancer chemotherapy, and examined the effect of changes in standard of EPs and temperature on drug emission. Methods We evaluated the EP data of patients treated with Baxter Infusor® LV5 and SV2.5 in terms of emission rate, relationship between 5-FU prescription amount and emission rate, and relationship between emission rate and monthly air temperature in LV5 and SV2.5. The number of EPs sampled in the study was N = 5708 (n = 2988 for LV5 and n = 2720 for SV2.5). Results In LV5, the emission rate varied from 88 to 97% (median 94.0%), whereas in SV2.5, the emission rate was observed as 97 to 98% (median 97.4%). The 5-FU prescription amount and the emission rate were not correlated in LV5 and SV2.5, respectively (LV5; y = − 0.0015x + 97.305, R2 = 0.0226, SV2.5; y = − 0.001x + 100.25, R2 = 0.0466). LV5 showed a higher emission rate in the months with higher air temperature and a lower emission rate in the month with lower air temperature. In addition, LV5 showed a significant reduction in emission rate compared with SV2.5 in all months (P Conclusions In this study, we clarified that air temperature is an important factor that affects the drug emission of EPs. Therefore, it is necessary to examine the conditions for total fluid volume suitable for the air temperature in each region and to provide sufficient information to patients.

Background The dissemination of antimicrobial-resistant bacteria (ARB) and the transfer of antimicrobial resistance genes (ARGs) are a threat to public health. Antibiotics are indispensable therapeutic agents essential for the treatment of infectious diseases; however, inappropriate use of antibiotics leads to the emergence of ARB. It is established that hospitals are closely involved in the spread of antimicrobial resistance (AMR), which impedes antibiotic treatment and subsequently increases mortality. In addition, excrement of patients or healthy carriers of ARB are discharged from the hospital sewage through the wastewater treatment plant (WWTP) into the rivers, causing an AMR burden on the environment.Method Metagenomic analysis was performed on the hospital sewage samples, followed by whole genome sequencing of the extended spectrum β-lactamase (ESBL)-producing organisms (EPOs). A comparative genome analysis was also performed between EPO isolates from sewage and clinical isolates.Results Metagenomic analysis showed that the hospital sewage tanks had bacterial flora corresponding to the human gut. During the study period, the hospital was relocated to a newly constructed building with new sewage tanks; however, the presence of ARB/ARGs in the new hospital sewage tanks became markedly equivalent to that of the old hospital within one month. The ESBL blaCTX−M and carbapenemase blaIMP genes were not much detected in the original hospital sewage samples by metagenome analysis, but selection on CHROMagar ESBL increased the sensitivity to detect those β-lactamase genes. Comparative genome analysis between sewage and clinical EPO isolates revealed partial similarity; however, most EPO isolates exhibited a notable difference (≥ 50) in single nucleotide variations based on core-genome phylogeny. This result suggests that only some of the sewage EPO isolates were originated from the clinical patient. Therapeutic agents in the hospital sewage were analyzed and the concentration of levofloxacin and clarithromycin was 0.0325 and 0.0135 µg/mL, respectively.Conclusions Whole genome analysis between sewage and clinical isolates suggested that healthy or asymptomatic carriers may be involved in the contamination of hospital sewage. Moreover, the hospital sewage tank may serve as a hotspot for the horizontal transfer of ARGs under the selective pressure of antimicrobial agents. Therefore, ARB monitoring in hospital sewage is expected to detect the presence of carriers prior to nosocomial ARB outbreaks. In addition, hospital wastewater should be treated suitably to bring ARB below detectable levels to reduce the environmental AMR burden.

We report the first case of bacteremia caused by Veillonella atypica in a morbid elderly female patient who developed obstructive pyelonephritis. She was treated with ceftriaxone and ureteral stenting; this is the first report of V. atypica infection in humans. Species identification was performed by multiplex PCR and sequencing of rpoB. The strain was susceptible to metronidazole and clindamycin but resistant to benzylpenicillin, ampicillin, ampicillin/sulbactam, and moxifloxacin.

Escherichia coli strain TUM2139 was isolated from a stool sample from a 9-year-old girl on 16 June 2004. This strain was categorized as Shiga toxin-producing Escherichia coli (STEC) because the Shiga-like toxin gene stx 1 was detected by immunochromatography and PCR assay. The strain was highly resistant to cefotaxime (256 μg/ml) and was also resistant to cefepime, cefpodoxime, ceftriaxone, and aztreonam. In the presence of 4 μg of clavulanic acid per ml, the MIC of cefotaxime decreased to ≤0.12 μg/ml, indicating that this strain was an extended-spectrum β-lactamase (ESBL) producer. Cefotaxime resistance was transferred to E. coli C600 by conjugation at a frequency of 3.0 × 10 −6 . A PCR assay was performed with primer sets specific for TEM-type and SHV-type ESBLs and for the CTX-M-2 (Toho-1), CTX-M-3, and CTX-M-9 groups of ESBLs. A specific signal was observed with the primer set specific for the CTX-M-9 group of β-lactamases. This β-lactamase was confirmed to be the ESBL CTX-M-18 by DNA sequencing. This is the first report of an ESBL-producing STEC isolate.

Sheet-shaped carriers, having both obverse and reverse surfaces and thus a large contact area for targeting a site, have several advantages over spherical-shaped carriers, which have an extremely small contact area for targeting sites. Here, we proposed a novel method to prepare a free-standing ultrathin and biocompatible nanosheet having heterosurfaces, by a combination of four processes: (1) specific adsorption of recombinant human serum albumin (rHSA) molecules onto a patterned octadecyltrimethoxysilane self-assembled monolayer region (ODS-SAM), (2) preparation of nanosheets of rHSA molecules bearing thiol groups (SH-rHSA) via two-dimensionally disulfide crosslinking, (3) surface modification of the resulting nanosheet, and (4) preparation of the free-standing nanosheet by detachment from the ODS-SAM. The SH-rHSA molecules at pH 5.0 and a concentration of 1 μg/mL were specifically adsorbed on the patterned ODS-SAM regions by hydrophobic interaction, and were two-dimensionally crosslinked in the presence of copper ion as an oxidant. The rHSA-nanosheets were then simply detached from the ODS-SAM by treatment with surfactant. We succeeded in the preparation of rectangular (10 μm × 30 μm) and ultrathin (4.5 ± 1.0 nm) rHSA-nanosheets on a patterned ODS-SAM, and could also obtain free-standing rHSA-nanosheets having heterosurfaces by surface modification with fluorescent latex beads. Thus, the rHSA-nanosheets having heterosurfaces could be regarded as a new biomaterial for drug carriers, hemostatic reagents, wound dressing for burn injury, and so forth. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009