Population structure of Japanese extraintestinal pathogenic Escherichia coli and its relationship with antimicrobial resistance.

Objectives: To define the population structure of extraintestinal pathogenic Escherichia coli (ExPEC) in Japan and its relationship with antimicrobial resistance and the major resistance mechanisms for fluoroquinolones and ß-lactams, we designed a multicentre prospective study. Methods: A total of 329 ExPEC isolates were collected at 10 Japanese acute-care hospitals during December 2014. We defined the clonal groups of ExPEC by fumC and fimH sequencing (CH typing). Antimicrobial susceptibility testing of 18 agents and the detection of mutations in quinolone resistance-determining regions (QRDRs) and ß-lactamases were performed. Results: Among the study isolates, 103 CH types were found, and CH40-30 (25%) and another 10 CH types (35% in total) constituted the major ExPEC population. Ciprofloxacin non-susceptibility, ESBLs and MDR phenotypes were found in 34%, 22% and 33%, respectively. CH40-30, corresponding to the C/H30 clade of the global pandemic ST131 clone, was associated with four QRDR mutations (100%) and bla CTX-M (60%) and was the most frequent type in 15 antimicrobial-non-susceptible populations (dominating 39%-75% of each population, the highest prevalence for ciprofloxacin), the ESBL producers (70%) and the MDR isolates (59%). Isolates that were non-susceptible to nalidixic acid and low-level resistant to ciprofloxacin with one or two QRDR mutations represented 16% of the study isolates and were distributed among the eight major and non-major CH types. Conclusions: More than half of the ExPEC population in Japan consisted of 11 major clones. Of these clones, the CH40-30-ST131-C/H30 clone was the predominant antimicrobial-resistant population. The presence of major clones with low-level ciprofloxacin resistance supports the potential future success of a non-ST131 fluoroquinolone-resistant clone.

Complete adherence to evidence-based quality-of-care indicators for Staphylococcus aureus bacteremia resulted in better prognosis.

PURPOSE: Staphylococcus aureus bacteremia (SAB) is a serious clinical condition associated with high morbidity and mortality. Recent studies have revealed that adherence to evidence-based quality-of-care indicators (QCIs) for the management of SAB could result in reduced mortality. We aimed to determine whether compliance with QCIs was associated with mortality and whether compliance with QCIs predicted the mortality of patients with SAB. METHODS: In a university hospital in Kyoto, Japan, SAB patients, who survived at least 14 days after positive blood cultures were analyzed from 2006 to 2014 to assess their compliance with QCIs and the trend in mortality. In addition, the predicted mortality, which was stratified by the number of fulfilled QCIs (QCI points), was calculated. In this study, the following five main QCI points were evaluated: (1) follow-up blood cultures; (2) early source control when applicable; (3) echocardiography; (4) the early use of appropriate antibiotics, and (5) the appropriate duration of therapy. RESULTS: We identified 477 eligible SAB cases, of which 199 were MRSA cases (41.7 %). The proportion of SAB cases in which the physicians adhered to at least four QCIs increased gradually from 47.5 % in 2006 to 79.3 % in 2014 (P = 0.001); whereas, the 30-day mortality decreased from 10.0 to 3.4 % after treatment completion. CONCLUSIONS: With an increase in the proportion of SAB cases adhering to QCIs, better prognoses were observed for patients with SAB. The QCI points reflected the 30-day mortality.

Clinical and microbiologic characteristics of cefotaxime-non-susceptible Enterobacteriaceae bacteremia: a case control study.

BACKGROUND: Cefotaxime plays an important role in the treatment of patients with bacteremia due to Enterobacteriaceae, although cefotaxime resistance is reported to be increasing in association with extended-spectrum ß-lactamase (ESBL) and AmpC ß-lactamase (AmpC). METHODS: We conducted a case-control study in a Japanese university hospital between 2011 and 2012. We assessed the risk factors and clinical outcomes of bacteremia due to cefotaxime-non-susceptible Enterobacteriaceae (CTXNS-En) and analyzed the resistance mechanisms. RESULTS: Of 316 patients with Enterobacteriaceae bacteremia, 37 patients with bacteremia caused by CTXNS-En were matched to 74 patients who had bacteremia caused by cefotaxime-susceptible Enterobacteriaceae (CTXS-En). The most common CTXNS-En was Escherichia coli (43%), followed by Enterobacter spp. (24%) and Klebsiella spp. (22%). Independent risk factors for CTXNS-En bacteremia included previous infection or colonization of CTXNS-En, cardiac disease, the presence of intravascular catheter and prior surgery within 30 days. Patients with CTXNS-En bacteremia were less likely to receive appropriate empirical therapy and to achieve a complete response at 72 h than patients with CTXS-En bacteremia. Mortality was comparable between CTXNS-En and CTXS-En patients (5 vs. 3%). CTXNS-En isolates exhibited multidrug resistance but remained highly susceptible to amikacin and meropenem. CTX-M-type ESBLs accounted for 76% of the ß-lactamase genes responsible for CTXNS E. coli and Klebsiella spp. isolates, followed by plasmid-mediated AmpC (12%). Chromosomal AmpC was responsible for 89% of CTXNS Enterobacter spp. isolates. CONCLUSIONS: CTXNS-En isolates harboring ESBL and AmpC caused delays in appropriate therapy among bacteremic patients. Risk factors and antibiograms may improve the selection of appropriate therapy for CTXNS-En bacteremia. Prevalent mechanisms of resistance in CTXNS-En were ESBL and chromosomal AmpC.

Global Escherichia coli Sequence Type 131 Clade with blaCTX-M-27 Gene.

The Escherichia coli sequence type (ST) 131 C2/H30Rx clade with the blaCTX-M-15 gene had been most responsible for the global dissemination of extended-spectrum ß-lactamase (ESBL)-producing E. coli. ST131 C1/H30R with blaCTX-M-27 emerged among ESBL-producing E. coli in Japan during the late 2000s. To investigate the possible expansion of a single clade, we performed whole-genome sequencing for 43 Japan and 10 global ST131 isolates with blaCTX-M-27 (n = 16), blaCTX-M-14 (n = 16), blaCTX-M-15 (n = 13), and others (n = 8). We also included 8 ST131 genomes available in public databases. Core genome-based analysis of 61 isolates showed that ST131 with blaCTX-M-27 from 5 countries formed a distinct cluster within the C1/H30R clade, named C1-M27 clade. Accessory genome analysis identified a unique prophage-like region, supporting C1-M27 as a distinct clade. Our findings indicate that the increase of ESBL-producing E. coli in Japan is due mainly to emergence of the C1-M27 clade.

Interspecies Dissemination of a Mobilizable Plasmid Harboring blaIMP-19 and the Possibility of Horizontal Gene Transfer in a Single Patient.

Carbapenemase-producing Gram-negative bacilli have been a global concern over the past 2 decades because these organisms can cause severe infections with high mortality rates. Carbapenemase genes are often carried by mobile genetic elements, and resistance plasmids can be transferred through conjugation. We conducted whole-genome sequencing (WGS) to demonstrate that the same plasmid harboring a metallo-ß-lactamase gene was detected in two different species isolated from a single patient. Metallo-ß-lactamase-producing Achromobacter xylosoxidans (KUN4507), non-metallo-ß-lactamase-producing Klebsiella pneumoniae (KUN4843), and metallo-ß-lactamase-producing K. pneumoniae (KUN5033) were sequentially isolated from a single patient and then analyzed in this study. Antimicrobial susceptibility testing, molecular typing (pulsed-field gel electrophoresis and multilocus sequence typing), and conjugation analyses were performed by conventional methods. Phylogenetic and molecular clock analysis of K. pneumoniae isolates were performed with WGS, and the nucleotide sequences of plasmids detected from these isolates were determined using WGS. Conventional molecular typing revealed that KUN4843 and KUN5033 were identical, whereas the phylogenetic tree analysis revealed a slight difference. These two isolates were separated from the most recent common ancestor 0.74 years before they were isolated. The same resistance plasmid harboring blaIMP-19 was detected in metallo-ß-lactamase-producing A. xylosoxidans and K. pneumoniae Although this plasmid was not self-transferable, the conjugation of this plasmid from A. xylosoxidans to non-metallo-ß-lactamase-producing K. pneumoniae was successfully performed. The susceptibility patterns for metallo-ß-lactamase-producing K. pneumoniae and the transconjugant were similar. These findings supported the possibility of the horizontal transfer of plasmid-borne blaIMP-19 from A. xylosoxidans to K. pneumoniae in a single patient.

Bundled strategies against infection after liver transplantation: Lessons from multidrug-resistant Pseudomonas aeruginosa.

Infection is a life-threatening complication after liver transplantation (LT). A recent outbreak of multidrug-resistant Pseudomonas aeruginosa triggered changes in our infection control measures. This study investigated the usefulness of our bundled interventions against postoperative infection after LT. This before-and-after analysis enrolled 130 patients who underwent living donor or deceased donor LT between January 2011 and October 2014. We initiated 3 measures after January 2013: (1) we required LT candidates to be able to walk independently; (2) we increased the hand hygiene compliance rate and contact precautions; and (3) we introduced procalcitonin (PCT) measurement for a more precise determination of empirical antimicrobial treatment. We compared factors affecting the emergence of drug-resistant microorganisms, such as the duration of antimicrobial and carbapenem therapy and hospital stay, and outcomes such as bacteremia and death from infection between before (n = 77) and after (n = 53) the LT suspension period. The utility of PCT measurement was also evaluated. Patients' backgrounds were not significantly different before and after the protocol revision. Incidence of bacteremia (44% versus 25%; P = 0.02), detection rate of multiple bacteria (18% versus 4%; P = 0.01), and deaths from infections (12% versus 2%; P = 0.04) significantly decreased after the protocol revision. Duration of antibiotic (42.3 versus 25.1 days; P = 0.002) and carbapenem administration (15.1 versus 5.2 days; P < 0.001) and the length of postoperative hospital stay (85.4 versus 63.5 days; P = 0.048) also decreased after the protocol revision. PCT mean values were significantly higher in the bacteremia group (10.10 ng/mL), compared with the uneventful group (0.65 ng/mL; P = 0.002) and rejection group (2.30 ng/mL; P = 0.02). One-year overall survival after LT significantly increased in the latter period (71% versus 94%; P = 0.001). In conclusion, the bundled interventions were useful in preventing infections and lengthening overall survival after LT.

Epidemiology of invasive fungal infections after liver transplantation and the risk factors of late-onset invasive aspergillosis.

Invasive fungal infection (IFI) in liver transplant recipients is associated with poor outcomes. Targeted antifungal prophylaxis is recommended for high-risk populations; however, the epidemiology of IFI has changed, and the risk criteria remain unclear. In addition, the risk factors for late-onset invasive aspergillosis (IA) have not been fully characterized. We examined 279 recipients over 16 years of age to uncover their IFI epidemiology, clinical characteristics and outcomes. In addition, a case-control study was performed to identify the risk factors of late-onset IA. Of the 279 recipients, 96.1% underwent living donor liver transplantation. Antifungal prophylaxis was administered to 80.6% of the recipients. IFI occurred in 15 patients, among which 8 cases were early-onset (≤90 days after liver transplantation) and 7 cases were late-onset (>90 days after liver transplantation). Five of the late-onset cases were invasive pulmonary aspergillosis, and 2 were fungemia cases. The mortality rate of late-onset IA was 80.0%. According to a multivariate analysis, steroid use before liver transplantation, bloodstream infection within 90 days after liver transplantation and reoperation within 90 days after liver transplantation were significant risk factors for late-onset IA after liver transplantation. The prevalence of IFI was low in our population given that over 80% of liver recipients received antifungal prophylaxis. The prognosis of late-onset IA remains poor, and predictors associated with late-onset IA, such as steroid use before liver transplantation, bloodstream infection and reoperation after liver transplantation, may help clinicians to optimize prevention measures for these devastating infections.

Oral administration and younger age decrease plasma concentrations of voriconazole in pediatric patients.

Voriconazole is used for treating or preventing invasive aspergillosis and other invasive fungal infections. To minimize adverse reactions and to maximize treatment effects, therapeutic drug monitoring should be performed. However, it is challenging to optimize daily voriconazole dosing because limited data have been published so far on pediatric patients. We retrospectively analyzed voriconazole concentrations in patients aged 0-18 years. In addition, a literature review was conducted. In our study cohort, younger age and oral administration were significantly associated with lower plasma voriconazole concentrations (P < 0.01). An unfavorable outcome was associated with low concentrations of voriconazole (P = 0.01). Reports of voriconazole administration in pediatric patients show that higher doses are required in younger children and in patients receiving oral administration. Hence, the current data suggest that we should escalate both initial and maintenance doses of voriconazole in pediatric patients, particularly in patients of younger age receiving an oral administration of voriconazole.

Genetic, phenotypic and matrix-assisted laser desorption ionization time-of-flight mass spectrometry-based identification of anaerobic bacteria and determination of their antimicrobial susceptibility at a University Hospital in Japan.

The accuracies of matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) and the phenotypic method using VITEK 2 were compared to the accuracy of 16S rRNA sequence analysis for the identification of 170 clinically isolated anaerobes. The antimicrobial susceptibility of the isolates was also evaluated. Genetic analysis identified 21 Gram-positive species in 14 genera and 29 Gram-negative species in 11 genera. The most frequently isolated genera were Prevotella spp. (n = 46), Bacteroides spp. (n = 25) and Clostridium spp. (n = 25). MALDI-TOF MS correctly identified more isolates compared with VITEK 2 at the species (80 vs. 58%, respectively; p < 0.01) and genus (85 vs. 71%, respectively; p < 0.01) levels. More than 90% of the isolates of the three major genera identified (Prevotella, Bacteroides, and Clostridium species other than Clostridium difficile) were susceptible to beta-lactam/beta-lactamase inhibitor combinations, carbapenems, metronidazole and chloramphenicol. MALDI-TOF MS provided better identification results than VITEK2. Commonly used anti-anaerobic agents indicated that the isolates of the three most frequently identified anaerobic genera exhibited good antimicrobial susceptibility.

[Vancomycin-Resistant Enterococci].

Vancomycin-resistant enterococci (VRE) have been detected from all over Japan since 1996. However, the incidence has been relatively low. In 2006, we organized Kyoto VRE surveillance group, established a VRE control program, and conducted an investigation which was to control the post-outbreak prevalence of VRE in the affected Kyoto region. The study period was from 2005 to 2010. Faecal samples were subjected to VRE screening, and vancomycin resistance genes were detected by polymerase chain reaction (PCR). A VRE control program consists of a laboratory-based faecal VRE screening system, annual surveillance of hospital inpatients and the promotion of adequate infection control measures. Number of VRE-detected patients was significantly smaller in hospitals with routine laboratory-based faecal VRE screening. From an- nual surveillance, the rate of faecal VRE carriage among the patients enrolled in the annual surveillance in- creased until 2007, when it reached 24(1.2%) of the 2,035 enrolled patients. The rate began to decrease in 2008 and, by 2010, reached a low of 4(0.17%) of the 2,408 enrolled patients. While VRE did spread within the Kyoto region, our program succeeded in controlling the overall VRE spread. [Review].

Multicenter retrospective study of cefmetazole and flomoxef for treatment of extended-spectrum-ß-lactamase-producing Escherichia coli bacteremia.

The efficacy of cefmetazole and flomoxef (CF) for the treatment of patients with extended-spectrum ß-lactamase-producing Escherichia coli (ESBL-EC) bacteremia (ESBL-CF group) was compared with that of carbapenem treatment for ESBL-EC patients (ESBL-carbapenem group) and with that of CF treatment in patients with non-ESBL-EC bacteremia (non-ESBL-CF group). Adult patients treated for E. coli bacteremia in four hospitals were retrospectively evaluated. The 30-day mortality rates in patients belonging to the ESBL-CF, ESBL-carbapenem, and non-ESBL-CF groups were compared as 2 (empirical and definitive therapy) cohorts. The adjusted hazard ratios (aHRs) for mortality were calculated using Cox regression models with weighting according to the inverse probability of propensity scores for receiving CF or carbapenem treatment. The empirical-therapy cohort included 104 patients (ESBL-CF, 26; ESBL-carbapenem, 45; non-ESBL-CF, 33), and the definitive-therapy cohort included 133 patients (ESBL-CF, 59; ESBL-carbapenem, 54; non-ESBL-CF, 20). The crude 30-day mortality rates for patients in the ESBL-CF, ESBL-carbapenem, and non-ESBL-CF groups were, respectively, 7.7%, 8.9%, and 3.0% in the empirical-therapy cohort and 5.1%, 9.3%, and 5.0% in the definitve-therapy cohort. In patients without hematological malignancy and neutropenia, CF treatment for ESBL-EC patients was not associated with mortality compared with carbapenem treatment (empirical-therapy cohort: aHR, 0.87; 95% confidence interval [CI], 0.11 to 6.52; definitive therapy cohort: aHR, 1.04; CI, 0.24 to 4.49). CF therapy may represent an effective alternative to carbapenem treatment for patients with ESBL-EC bacteremia for empirical and definitive therapy in adult patients who do not have hematological malignancy and neutropenia.

Management bundles for candidaemia: the impact of compliance on clinical outcomes.

OBJECTIVES: The Mycoses Forum in Japan has developed management bundles for candidaemia to incorporate into bedside practice. The aim of this study was to investigate nationwide compliance with the bundles and their impact on clinical outcomes. METHODS: Non-neutropenic patients treated with antifungals for candidaemia were surveyed. Bundles consist of nine items to complete. Data were sent to the central office between July 2011 and April 2012. RESULTS: Six hundred and eight patients were analysed. The compliance rate for achieving all elements was 6.9%, and it increased to 21.4% when compliance was analysed by the bundle except for oral switch. There was a significant difference in clinical success between patients with and without compliance [92.9% versus 75.8% (P=0.011)]. Compliance with the bundles, however, failed to be an independent factor associated with favourable outcomes. When step-down oral therapy was excluded from the elements of compliance, compliance with the bundles was revealed to be an independent predictor of clinical success (OR 4.42, 95% CI 2.05-9.52) and mortality (OR 0.27, 95% CI 0.13-0.57). Independent individual elements contributing to clinical success were removal of central venous catheters within 24 h, assessment of clinical efficacy on the third to the fifth day and at least 2 weeks of therapy after clearance of candidaemia. CONCLUSIONS: Compliance with the bundles for candidaemia had a beneficial effect on clinical outcomes. Promotion of the bundles approach may have the potential to narrow the gap between clinical evidence and bedside practice.

CTX-M-27- and CTX-M-14-producing, ciprofloxacin-resistant Escherichia coli of the H30 subclonal group within ST131 drive a Japanese regional ESBL epidemic.

OBJECTIVES: The global increase in ESBL-producing Escherichia coli is associated with the ST131 clonal group, especially its CTX-M-15-producing H30Rx subset. To understand the rapid spread of ESBL-producing E. coli in Japan, we investigated the molecular epidemiology and ESBL-associated genetic environments of Japanese ST131 isolates. METHODS: Between 2001 and 2012, 1079 ESBL-producing E. coli isolates were collected at 10 Japanese acute-care hospitals. ESBL types, ST131 status, fimH allele, H30Rx-defining sequences and ESBL-associated genetic environments were defined using PCR and sequencing. Subclonal groups were defined based on fimH allele and H30Rx status. RESULTS: Overall, 461 (43%) of the 1079 ESBL-producing E. coli isolates represented ST131. According to fimH-based subclonal typing, the ST131 isolates included 398 fimH allele 30 (H30) isolates, 49 H41 isolates, 10 H22 isolates and 4 other fimH-type isolates. The 398 H30 isolates included 396 ciprofloxacin-resistant H30R isolates, of which 64 (16%) represented the H30Rx subset. Between 2001 and 2007, the CTX-M-14-producing H30R subgroup predominated, accounting for 46% of ST131 isolates, whereas the CTX-M-27-producing H30R and CTX-M-15-producing H30Rx subgroups were rarely detected. In contrast, from 2008 onward the latter two subgroups rose to dominance, accounting for 45% and 24% of ST131 isolates, respectively, versus only 15% for the (formerly dominant) CTX-M-14-producing H30R subgroup. The emergent CTX-M-27-H30R subgroup frequently had an IS26-ΔISEcp1-blaCTX-M-27-ΔIS903D-IS26-like structure, whereas the older CTX-M-14-H30R subgroup frequently had an ISEcp1-blaCTX-M-14-IS903D-like structure. CONCLUSIONS: This Japanese regional ESBL-producing E. coli epidemic is closely associated with newly identified CTX-M-27- and CTX-M-14-producing ST131 H30R subclonal groups and with mobile elements IS26, ISEcp1 and IS903D.

Detection of extended-spectrum-ß-lactamase-producing Escherichia coli ST131 and ST405 clonal groups by matrix-assisted laser desorption ionization-time of flight mass spectrometry.

Escherichia coli sequence type 131 (ST131) and ST405 are important clonal groups, because they are associated with the global increase of extended-spectrum-ß-lactamase (ESBL) producers. Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) is emerging as a rapid, inexpensive, and accurate method for bacterial identification. We investigated the detection performance of MALDI-TOF for the ST131 and ST405 clonal groups using 41 ST131-O25b, 26 ST131-O16, and 41 ST405 ESBL-producing isolates and 41 ESBL-producing isolates frrom other STs. The main spectra representing each clonal group were used for classification with Biotyper (Bruker Daltonics GmbH, Bremen, Germany). The peak that had the highest area under the receiver-operating characteristic curve generated by ClinProTools (Bruker) was detected with FlexAnalysis (Bruker), and an optimal signal-to-noise ratio cutoff was determined. The optimal detection models were generated by ClinProTools. Classification by Biotyper could detect the ST131-whole (O25b and O16 together) group with a sensitivity of 98.5% and a specificity of 93.9%. With FlexAnalysis, a peak of 9,720 Da detected the ST131-whole group with a sensitivity of 97.0% and a specificity of 91.5% at a cutoff value of 8.0. The ClinProTools models exhibited good performance for the detection of the ST131-whole group (sensitivity and specificity, 94.0% and 92.7%, respectively), the ST131-O25b group (95.1% and 98.2%, respectively), and the ST405 group (90.2% and 96.3%, respectively). MALDI-TOF MS had high detection performance for the ST131-whole, ST131-O25b, and ST405 clonal groups. MALDI-TOF MS should be considered as an alternative method to monitor the epidemiology of the ESBL-producing E. coli ST131 and ST405 clonal groups.

Redo living-donor lobar lung transplantation for bronchiolitis obliterans associated with antibody-mediated rejection.

Living-donor lobar lung transplantation (LDLLT) is an established therapy for patients with end-stage lung disease, but living-donor lobar lung retransplantation (re-LDLLT) is rarely reported. We previously reported a case of unilateral antibody-mediated rejection after LDLLT in the presence of newly formed donor-specific antibodies against a right-lobe donor. The same patient developed contralateral bronchiolitis obliterans, resulting in bilateral bronchiolitis obliterans, but re-LDLLT was successful. Pathological findings of the explanted lungs were consistent with the clinical course of the patient. One year after re-LDLLT, the patient is doing well without any anti-human leukocyte antigen antibodies. Four lobes from four different donors were transplanted in this patient. The first two lobes were rejected eventually, but the two lobes implanted later presented no signs of rejection at least for 1 year after the transplant. Herein, we report this rare case and compare the clinical course and pathological findings.

Pneumocystis polymerase chain reaction and blood (1→3)-ß-D-glucan assays to predict survival with suspected Pneumocystis jirovecii pneumonia.

Pneumocystis polymerase chain reaction (PCR) and blood (1→3)-ß-D-glucan assays are known to be useful for the diagnosis of Pneumocystis pneumonia (PCP). However, their impact on the outcome of clinically suspected PCP patients has not yet been elucidated. Between January 2008 and July 2011, we prospectively observed 190 immunocompromised patients who had ground-glass opacity on chest computed tomography scans and were suspected to have PCP. The blood ß-D-glucan levels of these patients were measured, and PCR was used to detect Pneumocystis jirovecii in the respiratory samples. The 30-day mortality rates and related factors were assessed. The 30-day mortality rate of all included patients was 21.6%. Both ß-D-glucan-positive (10.1%) and PCR-positive patients (15.0%) had significantly lower mortality rates than ß-D-glucan-negative (28.1%) or PCR-negative patients (30.1%). All of the 13 definite PCP patients had positive PCR and ß-D-glucan results, received anti-PCP treatments, and survived. Among the 72 patients who were negative for microscopic detection of P. jirovecii but received anti-PCP treatments, positive PCR results (odds ratio [OR], 0.14; 95% confidence interval [CI], 0.02-0.74), a high Sequential Organ Failure Assessment score (OR, 1.42; CI, 1.08-1.88), and positive ß-D-glucan levels (OR 0.25, CI 0.06-1.02) were associated with mortality rates using stepwise logistic regression analyses. A positive Pneumocystis PCR or ß-D-glucan test was a candidate predictor of survival in patients who were suspected of having PCP, even though negative for visual detection by microscopy.

Clinical practice guidelines for therapeutic drug monitoring of arbekacin: a consensus review of the Japanese Society of Chemotherapy and the Japanese Society of Therapeutic Drug Monitoring.

Arbekacin (ABK) was approved and widely used in Japan for treatment of patients infected with MRSA, and TDM was introduced in clinical practice. The Japanese Society of Chemotherapy and the Japanese Society of Therapeutic Drug Monitoring decided to develop a clinical practice guidelines for TDM of ABK for the following reasons. First, although the daily dose of 150-200 mg was approved in Japan, recent PK-PD studies revealed that higher serum concentration is required to achieve better clinical efficacy and several findings concerning the usefulness of higher dosage regimen have obtained recently. Second, although maximal concentrations that obtained immediately after the end of administration (Cmax) was generally adopted, the serum concentration at 1 h after initiation of administration [peak serum concentration (Cpeak)] proved to be more suitable as an efficacy indicator of aminoglycosides. Lastly, as ABK is approved only in Japan, no international practice guideline for TDM has not been available in ABK to date. This guideline evaluated the scientific data associated with serum ABK monitoring and provided recommendations based on the available evidence. Potential limitations of this guideline, however, include the findings that few prospective clinical trials of TDM of ABK are available in the treatment of MRSA infections and that most of the published literature describes observational studies.

Association of fluoroquinolone resistance, virulence genes, and IncF plasmids with extended-spectrum-ß-lactamase-producing Escherichia coli sequence type 131 (ST131) and ST405 clonal groups.

The global increase of extended-spectrum-ß-lactamase (ESBL)-producing Escherichia coli is associated with the specific clonal group sequence type 131 (ST131). In order to understand the successful spread of ESBL-producing E. coli clonal groups, we characterized fluoroquinolone resistance determinants, virulence genotypes, and plasmid replicons of ST131 and another global clonal group, ST405. We investigated 41 ST131-O25b, 26 ST131-O16, 41 ST405, and 41 other ST (OST) ESBL-producing isolates, which were collected at seven acute care hospitals in Japan. The detection of ESBL types, fluoroquinolone resistance-associated mutations (including quinolone resistance-determining regions [QRDRs]), virulence genotypes, plasmid replicon types, and IncF replicon sequence types was performed using PCR and sequencing. blaCTX-M, specifically blaCTX-M-14, was the most common ESBL gene type among the four groups. Ciprofloxacin resistance was found in 90% of ST131-O25b, 19% of ST131-O16, 100% of ST405, and 54% of OST isolates. Multidrug resistance was more common in the ST405 group than in the ST131-O25 group (56% versus 32%; P = 0.045). All ST131-O25b isolates except one had four characteristic mutations in QRDRs, but most of the isolates from the other three groups had three mutations in common. The ST131-O25b and ST405 groups had larger numbers of virulence genes than the OST group. All of the ST131-O25b and ST405 isolates and most of the ST131-O16 and OST isolates carried IncF replicons. The most prevalent IncF replicon sequence types differed between the four clonal groups. Both the ST131-O25b and ST405 clonal groups had a fluoroquinolone resistance mechanism in QRDRs, multidrug resistance, high virulence, and IncF plasmids, suggesting the potential for further global expansion and a need for measures against these clonal groups.

Clinical characteristics and risk factors of non-Candida fungaemia.

BACKGROUND: The incidence of fungaemia has been increasing worldwide. It is important to distinguish non-Candida fungaemia from candidaemia because of their different antifungal susceptibilities. The aims of this study were to investigate the clinical characteristics of non-Candida fungaemia and identify the clinical factors that differentiate it from candidaemia. METHODS: We investigated the clinical manifestations and mortality of non-Candida fungaemia in Kyoto University Hospital from 2004 to 2009. RESULTS: There were 110 episodes of fungaemia during the study period. There were 11 renal replacement therapy episodes of fungaemia due to non-Candida yeasts (10.0%), including 6 episodes with Cryptococcus neoformans, 4 with Trichosporon asahii, and 1 with Kodamaea ohmeri, in addition to 99 episodes of candidaemia (90.0%). The presence of collagen disease [odds ratio (OR) 9.00; 95% confidence interval (CI) 1.58-51.4; P=0.01] or renal replacement therapy (OR 15.0; 95% CI 3.06-73.4; P<0.01) was significantly more common in non-Candida fungaemia patients than in candidaemia patients. Prior colonisation by the species may be a predictor of non-Candida fungaemia. Non-Candida fungaemia had a higher mortality than candidaemia (54.5% versus 21.2%, P=0.03). CONCLUSIONS: Although Candida species frequently cause fungaemia, we should also be aware of non-Candida yeasts because of their high mortality, particularly among high-risk patients, such as those with collagen disease and those under renal replacement therapy. Prior colonisation by the causative organisms may be an important predictor of non-Candida fungaemia.

[Risk factors and clinical charasteristics of Stenotrophomonas maltophilia bacteremia: a comparison with bacteremia due to other glucose-non fermenters].

Stenotrophomonas maltophilia (SM) is an important nosocomial pathogen. Due to its intrinsic resistance to various therapeutic drugs, the optimal antimicrobial therapy is often delayed. From January 2005 to September 2012, we retrospectively compared drug susceptibilities, clinical backgrounds, and outcome of SM bacteremic patients (SM group) with these of other non fermentative gram negative bacilli bacteremic patients (non-SM group), at a tertiary-care hospital in Kyoto, Japan. Among the SM group, risk factors of 30-day mortality were evaluated. The SM group and non-SM group included 54 and 237 cases, respectively. Among the non-SM group, bacteremic patients due to Pseudomonas aeruginosa, Acinetobacter species, and other non-fermentative gram negative bacilli included 156, 68, and 13 patients, respectively. SM isolates were susceptible to trimethoprim-sulfamethoxazole and minocycline (82.0% and 100%, respectively). Non-SM isolates were susceptible to meropenem (88.6%), ceftazidime (88.6%), cefepime (85.2%), and amikacin (97.0%). Both SM and non-SM isolates were susceptible to levofloxacin (87.5% and 82.0%, respectively). The use of carbapenems, antipseudomonal cephalosporins, and isolation of SM within 30 days represented an independent risk factor for SM bacteremia. The 30 day mortality rate among the SM group was significantly higher compared with the non-SM group (35% vs 18%, odds ratio: 2.2, 95% CI: 1.2-4.3 p = 0.012). Among the SM group, an independent factor which was associated with 30-day mortality was the SOFA score. SM bacteremia showed a worse outcome compared with bacteremia due to non-SM. For the patients who present risk factors for SM bacteremia, empirical antimicrobial therapy including trimethoprim-sulfamethoxazole, minocycline or levofloxacin should be considered.