High-level levofloxacin-resistant emm12 group A Streptococcus, 2012-2018: A multicenter study in Taiwan.

High-level levofloxacin-resistant group A Streptococcus emerged in Taiwan in 2012. Among the 24 isolates identified, 23 belonged to emm12/ST36, most harbored the same GyrA and ParC mutations and were highly clonal. wgMLST showed them to be closely related to the Hong Kong scarlet fever outbreak strains. Continuous surveillance is warranted.

Rapid and Routine Molecular Typing Using Multiplex Polymerase Chain Reaction and MinION Sequencer.

Molecular typing is an essential tool that has been extensively applied in laboratories as well as in clinical settings. Next-generation sequencing technologies promise high-throughput and cost-effective molecular applications; however, the accessibility of these technologies is limited due to the high capital cost. Oxford Nanopore Technologies (ONT) offers a MinION device with the advantages of real-time data analysis, rapid library preparation, and low cost per test. However, the advantages of the MinION device are often overshadowed by its lower raw accuracy. Herein, we present a concise multilocus sequence typing protocol of Staphylococcus aureus using multiplex polymerase chain reaction and Rapid Barcoding Kit for barcoding and MinION device for sequencing. Moreover, to clarify the effects of carryover DNA on tasks that require high sequence accuracy, we used the MinION flow cell in successive runs of washing and reusing. Our results revealed that the MinION flow cell could achieve accurate typing of a total of 467 samples with 3,269 kilobase-long genes within a total of 5 runs. This thus demonstrates the effectiveness of a portable nanopore MinION sequencer in providing accurate, rapid, and routine molecular typing.

Overbooking for physical examination considering late cancellation and set-resource relationship.

BACKGROUND: Late cancellations of physical examination has severe impact on the operations of a physical examination center since it is often too late to fill vacancy. A booking control policy that considers overbooking is then one natural solution. Unlike appointment scheduling problems for clinics and hospitals, in which treating a patient mostly requires only one type of resource, a physical examination set typically requires multiple types of resources. Traditional methods that do not consider set-resource relationship thus may be inapplicable. METHODS: We formulate a stochastic mathematical programming model that maximizes the expected net reward, which is the examination revenue minus overage cost. A complete search algorithm and a greedy search algorithm are designed to search for optimal booking limits for all examination sets. To estimate the late cancellation probability for each individual consumer, we apply logistic regression to identify significant factors affecting the probability. After clustering is used to estimate individual probabilities, Monte Carlo simulation is conducted to generate probability distributions for the number of consumers without late cancellations. A discrete-event simulation is performance to evaluate the effectiveness of our proposed solution. RESULTS: We collaborate with a leading physical examination center to collect real data to evaluate our proposed overbooking policies. We show that the proposed overbooking policy may significantly increase the expected net reward. Our simulation results also help us understand the impact of overbooking on the expected number of customers and expected overage. A sensitivity analysis is conducted to demonstrate that the benefit of overbooking is insensitive to the accuracy of cost estimation. A Pareto efficiency analysis gives practitioners suggestions regarding policy determination considering multiple performance indications. CONCLUSIONS: Our proposed overbooking policies may greatly enhance the overall performance of a physical examination center.

Temporal Trend of ST131 Clone among Urinary Escherichia coli Isolates in the Community: A Taiwan National Surveillance from 2002 to 2016.

Sequence type (ST) 131 is a multidrug-resistant pandemic lineage of E. coli responsible for extraintestinal infections. Few surveillance data of ST131 included all antimicrobial-susceptible and -resistant isolates or focused on community-acquired urinary tract infection (UTI). From a population-based surveillance pool of 2997 outpatient urine E. coli isolates, 542 were selected for detection of ST131 based on ciprofloxacin and/or cefotaxime resistance. Pulsed-field gel electrophoresis (PFGE) was performed on all ST131 isolates to further determine their relatedness. The estimated overall ST131 prevalence in this community UTI cohort increased from 11.2% (in 2002-2004), 12.2% (in 2006-2008), 13.6% (in 2010-2012), to 17.4% in 2014-2016 (p < 0.01). In the ciprofloxacin-resistant/cefotaxime-resistant group, ST131 increased from 33.3% in 2002-2004 to 72.1% in 2014-2016 (p < 0.01). In the ciprofloxacin-resistant/cefotaxime-susceptible group, ST131 was found in 24.3% overall without significant increase in its prevalence over time. PFGE showed emergence of a cluster of ciprofloxacin-resistant/cefotaxime-resistant ST131 carrying Gr. 1 CTX-M ESBL in 2014-2016, especially 2016. Multivariate analysis revealed that age (≥65 y.o) and ciprofloxacin resistance were independent factors associated with ST131. This longitudinal surveillance showed that ciprofloxacin-resistant/cefotaxime-susceptible ST131 has been circulating in the community since 2002 but ciprofloxacin-resistant/cefotaxime-resistant ST131 increased rapidly in the later years.

In vitro activity of imipenem/relebactam, meropenem/vaborbactam, ceftazidime/avibactam, cefepime/zidebactam and other novel antibiotics against imipenem-non-susceptible Gram-negative bacilli from Taiwan.

OBJECTIVES: To investigate the susceptibility of imipenem-non-susceptible Escherichia coli (INS-EC), Klebsiella pneumoniae (INS-KP), Acinetobacter baumannii (INS-AB) and Pseudomonas aeruginosa (INS-PA) to novel antibiotics. METHODS: MICs were determined using the broth microdilution method. Carbapenemase and ESBL phenotypic testing and PCR for genes encoding ESBLs, AmpCs and carbapenemases were performed. RESULTS: Zidebactam, avibactam and relebactam increased the respective susceptibility rates to cefepime, ceftazidime and imipenem of 17 INS-EC by 58.8%, 58.8% and 70.6%, of 163 INS-KP by 77.9%, 88.3% and 76.1% and of 81 INS-PA by 45.7%, 38.3% and 85.2%, respectively. Vaborbactam increased the meropenem susceptibility of INS-EC by 41.2% and of INS-KP by 54%. Combinations of ß-lactams and novel ß-lactamase inhibitors or ß-lactam enhancers (BLI-BLE) were inactive against 136 INS-AB. In 58 INS-EC and INS-KP with exclusively blaKPC-like genes, zidebactam, avibactam, relebactam and vaborbactam increased the susceptibility of the partner ß-lactams by 100%, 96.6%, 84.5% and 75.9%, respectively. In the presence of avibactam, ceftazidime was active in an additional 85% of 20 INS-EC and INS-KP with exclusively blaOXA-48-like genes while with zidebactam, cefepime was active in an additional 75%. INS-EC and INS-KP with MBL genes were susceptible only to cefepime/zidebactam. The ß-lactam/BLI-BLE combinations were active against INS-EC and INS-KP without detectable carbapenemases. For INS-EC, INS-KP and INS-AB, tigecycline was more active than omadacycline and eravacycline but eravacycline had a lower MIC distribution. Lascufloxacin and delafloxacin were active in <35% of these INS isolates. CONCLUSIONS: ß-Lactam/BLI-BLE combinations were active in a higher proportion of INS-EC, INS-KP and INS-PA. The susceptibility of novel fluoroquinolones and tetracyclines was not superior to that of old ones.

Serotype Distribution and Antimicrobial Susceptibility of Streptococcus pneumoniae in Pre- and Post- PCV7/13 Eras, Taiwan, 2002-2018.

In Taiwan, the 7-valent pneumococcal conjugate vaccine (PCV7) was introduced in 2006 and a PCV13 national childhood catchup program was implemented in 2013. To delineate the trend of serotype distribution and antimicrobial susceptibility following vaccination programs, we investigated a total of 1845 Streptococcus pneumoniae isolates collected biennially between 2002 and 2018 over a 3-month period from 25 hospitals. The number of isolates collected over the years decreased significantly in all age groups, from a total of 320 isolates in 2002 (pre-PCV), to 196 in 2010 (post-PCV7/pre-PCV13), to 89 in 2018 (post-PCV13). Overall, PCV7/PCV13 serotypes comprised 66.9%/76.3%, 53.1%/78.1%, and 15.7%/31.5% of isolates in 2002, 2010, and 2018, respectively. The leading serotypes in the pre-PCV era were 23F, 19F, 6B, and 14, while serotype 19A predominated in the post-PCV7/pre-PCV13 era, but non-vaccine serotypes (NVT) 15A (18.0%) and 23A (15.7%) surpassed 19A (10.1%) to become the top two leading serotypes in 2018. All the major serotypes, including the emergent serotypes 15A and 23A, were multidrug-resistant with high rates of non-susceptibility to ß-lactam (except serotype 3) and several non-ß-lactam agents. PFGE and MLST revealed that while meropenem-susceptible serotype 15A-ST3058 isolates and a serotype 23A-ST338 clone existed in earlier years, rise and spread of meropenem-non-susceptible serotype 15A-ST63 and serotype 23A-ST166 clones occurred in recent years. We conclude that successive implementation of PCVs has led to a marked decrease in pneumococcal isolate burden, but the replacement by meropenem-non-susceptible NVT 15A and 23A highlights the need for continued local surveillance to track pneumococcal evolution in each region to help vaccine polyvalency decisions.

Physical fitness cognition, assessment, and promotion: A cross-sectional study in Taiwan.

INTRODUCTION: Many health organizations have promoted the importance of the health-related benefits of physical fitness and physical activity. Studies have evaluated effective public health practice aiming to understand the cognition of physical activity among youths and adolescents. However, studies investigating the level of cognition and knowledge of physical fitness among Asian adults are lacking. PURPOSE: This study aimed to investigate the self-awareness level of physical fitness and exercise prescription and the demand for physical fitness assessment among Taiwanese adults. METHODS: In January-July 2019, a cross-sectional anonymous survey was conducted using Research Electronic Data Capture to gather data on demographic data, cognition investigation of physical fitness and exercise prescription, cognitive test of physical fitness and exercise prescription, and demand for physical fitness assessment. RESULTS: The questionnaire was answered by 200 respondents. The rating for cognition investigation of physical fitness was 2.63-3.13 (unclear to mostly clear) and for exercise prescription was 2.05-2.76 (unclear) (rated on a 5-point Likert scale). Results show that lack of awareness was highest for health-related physical fitness, exercise prescription, and exercise progress planning. 98% of subjects did not know the latest recommended guidelines for physical activity, despite most agreeing that physical fitness and exercise are good for health. Most subjects (72%) indicated a willingness to accept self-pay service for physical fitness assessments. CONCLUSIONS: This is the first study to report on the demand for cognition, assessment, and promotion of physical fitness among Taiwanese adults. The study shows that the subjects widely lack knowledge in the cognition of physical fitness and exercise prescription. Furthermore, a self-pay service for the physical fitness assessment and individualized exercise prescription were acceptable to most subjects, especially those undergoing regular health examinations. The findings are encouraging and will aid support for health organizations and professionals in the development and management of promotion strategies on health-related physical fitness in preventive medicine and health promotion.

Molecular Epidemiology of Emerging Carbapenem Resistance in Acinetobacter nosocomialis and Acinetobacter pittii in Taiwan, 2010 to 2014.

This study investigated the molecular epidemiology of carbapenem-resistant Acinetobacter nosocomialis and Acinetobacter pittii (ANAP). Clinical isolates of Acinetobacter spp. collected by the biennial nationwide Taiwan Surveillance of Antimicrobial Resistance program from 2010 to 2014 were subjected to species identification, antimicrobial susceptibility testing, and PCR for detection of carbapenemase genes. Whole-genome sequencing or PCR mapping was performed to study the genetic surroundings of the carbapenemase genes. Among 1,041 Acinetobacter isolates, the proportion of ANAP increased from 11% in 2010 to 22% in 2014. The rate of carbapenem resistance in these isolates increased from 7.5% (3/40) to 22% (14/64), with a concomitant increase in their resistance to other antibiotics. The blaOXA-72 and blaOXA-58 genes were highly prevalent in carbapenem-resistant ANAP. Various genetic structures were found upstream of blaOXA-58 in different plasmids. Among the plasmids found to contain blaOXA-72 flanked by XerC/XerD, pAB-NCGM253-like was identified in 8 of 10 isolates. Conjugations of plasmids carrying blaOXA-72 or blaOXA-58 to A. baumannii were successful. In addition, three isolates with chromosome-located blaOXA-23 embedded in AbGRI1-type structure with disruption of genes other than comM were detected. Two highly similar plasmids carrying class I integron containing blaIMP-1 and aminoglycoside resistance genes were also found. The universal presence of blaOXA-272/213-like on A. pittii chromosomes and their lack of contribution to carbapenem resistance indicate its potential to be a marker for species identification. The increase of ANAP, along with their diverse mechanisms of carbapenem resistance, may herald their further spread and warrants close monitoring.

Molecular Epidemiology of Emerging blaOXA-23-Like- and blaOXA-24-Like-Carrying Acinetobacter baumannii in Taiwan.

The rate of recovery of carbapenem-resistant Acinetobacter baumannii (CRAB) isolates has increased significantly in recent decades in Taiwan. This study investigated the molecular epidemiology of CRAB with a focus on the mechanisms of resistance and spread in isolates with blaOXA-23-like or blaOXA-24-like All 555 CRAB isolates in our multicenter collection, which were recovered from 2002 to 2010, were tested for the presence of class A, B, and D carbapenemase genes. All isolates with blaOXA-23-like or blaOXA-24-like were subjected to pulsed-field gel electrophoresis, and 82 isolates (60 isolates with blaOXA-23-like and 22 isolates with blaOXA-24-like) were selected for multilocus sequence typing to determine the sequence type (ST) and clonal group (CG) and for detection of additional ß-lactamase and aminoglycoside resistance genes. The flanking regions of carbapenem and aminoglycoside resistance genes were identified by PCR mapping and sequencing. The localization of blaOXA was determined by S1 nuclease and I-CeuI assays. The numbers of CRAB isolates carrying blaOXA-23-like or blaOXA-24-like, especially those carrying blaOXA-23-like, increased significantly from 2008 onward. The blaOXA-23-like gene was carried by antibiotic resistance genomic island 1 (AbGRI1)-type structures located on plasmids and/or the chromosome in isolates of different STs (CG92 and novel CG786), whereas blaOXA-24-like was carried on plasmids in CRAB isolates of limited STs (CG92). No class A or B carbapenemase genes were identified. Multiple aminoglycoside resistance genes coexisted in CRAB. Tn6180-borne armA was found in 74 (90.2%) CRAB isolates, and 58 (70.7%) isolates had Tn6179 upstream, constituting AbGRI3. blaTEM was present in 38 (46.3%) of the CRAB isolates tested, with 35 (92.1%) isolates containing blaTEM in AbGRI2-type structures, and 61% of ampC genes had ISAba1 upstream. We conclude that the dissemination and spread of a few dominant lineages of CRAB containing various resistance island structures occurred in Taiwan.

Multiclonal emergence of levofloxacin-resistant group B Streptococcus, Taiwan.

OBJECTIVES: This study investigated the trend in antimicrobial resistance among group B Streptococcus (GBS) from a national surveillance programme in Taiwan and delineated characteristics of and factors associated with levofloxacin-resistant isolates. METHODS: Clinical isolates of all sample types and patient groups were collected from multiple hospitals biennially between 2002 and 2012. Susceptibilities to different antibiotics were determined by broth microdilution. Molecular studies of levofloxacin-resistant isolates included serotyping, PFGE, mutations in the QRDRs and MLST. RESULTS: A total of 1559 isolates were tested and all remained susceptible to penicillin, cephalosporins, meropenem and vancomycin. However, levofloxacin resistance increased from 2.2% (range 0%-3.3%) in 2002-06 to 6.2% (5.9%-7.5%) in 2008-12 (P = 0.016). Among the 88 levofloxacin-resistant isolates, the majority (79.5%) had the GyrA(S81L)+ParC(S79F/Y) double mutations and most (54.5%) were also resistant to clindamycin, erythromycin and tetracycline. The predominant genotype of the levofloxacin-resistant isolates was ST19/serotype III (43.2%). Four previously unreported genotypes, ST1 and its single-locus variants (ST920 and ST922)/serotype VI (28.4%) and ST1/serotype II (18.2%), were found to have circulated locally. Serotype III isolates were predominately from urine and female genital tract specimens and <65-year-old adult outpatients, while serotype II and VI isolates were mostly from respiratory and urine samples and >65-year-old inpatients. Multivariate analysis revealed that elderly age and respiratory samples were independent factors associated with levofloxacin resistance. CONCLUSIONS: Multiclonal emergence and dissemination of levofloxacin-resistant GBS isolates occurred in healthcare and community settings in Taiwan. Continuous molecular-level surveillance is important to detect new epidemic trends.

Prevalence of and risk factors for methicillin-resistant Staphylococcus aureus colonization among human immunodeficient virus-infected outpatients in Taiwan: oral Candida colonization as a comparator.

Human immuodeficency virus (HIV)-infected patients receiving highly active antiretroviral therapy (HAART) and community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) have increased in recent years in Taiwan. This study was undertaken to determine the prevalence of and risk factors for nasal and oral S. aureus and MRSA colonization among contemporary HIV-infected populations. Clinical variables for S. aureus and MRSA colonization among HIV-infected outpatients from three hospitals were analyzed and compared with those for oral Candida colonization. Genetic characteristics of MRSA isolates were analyzed. A total of 714 patients were screened for nasal S. aureus colonization, and a subset of 457 patients were also screened for oral S. aureus colonization. Of all patients, 79.4% were receiving HAART, and their mean CD4 count was 472 cells/mm3. The colonization rates in the oral cavity, nasal cavity, and at either site were 18.8%, 31.7%, and 36.8%, respectively, for S. aureus, and 3.1%, 4.4%, and 5.5%, respectively, for MRSA. These rates were all much lower than the previously reported rate of oral Candida colonization (52.4%). By multivariate analysis, a suppressed viral load (<200 copies/mL) protected against oral S. aureus, MRSA, and Candida colonization, and recent use of antibacterial agents protected against oral and nasal S. aureus colonization. Recent incarceration increased the risk of nasal MRSA colonization, while recent hospitalization, tuberculosis, older age, and intravenous drug use increased the risk of oral Candida colonization. Candida spp. did not augment S. aureus or MRSA colonization in the oral cavity. Most of the 41 MRSA isolates recovered belonged to the SCCmec IV/pvl-negative (51.2%) and VT/pvl-positive (26.8%) ST59 local prevalent CA-MRSA clones. Distinct carriage rates demonstrated here suggested that mucosal immunity against colonization might differ in terms of microbes and sites. A decreased risk in oral carriage of MRSA and Candida might be a benefit of HAART.

Prevalence and characteristics of pks genotoxin gene cluster-positive clinical Klebsiella pneumoniae isolates in Taiwan.

The pks gene cluster encodes enzymes responsible for the synthesis of colibactin, a genotoxin that has been shown to induce DNA damage and contribute to increased virulence. The present study investigated the prevalence of pks in clinical K. pneumoniae isolates from a national surveillance program in Taiwan, and identified microbiological and molecular factors associated with pks-carriage. The pks gene cluster was detected in 67 (16.7%) of 400 isolates from various specimen types. Multivariate analysis revealed that isolates of K1, K2, K20, and K62 capsular types (p < 0.001), and those more susceptible to antimicrobial agents (p = 0.001) were independent factors strongly associated with pks-carriage. Phylogenetic studies on the sequence type (ST) and pulsed-field gel electrophoresis patterns indicated that the pks-positive isolates belong to a clonal group of ST23 in K1, a locally expanding ST65 clone in K2, a ST268-related K20 group, and a highly clonal ST36:K62 group. Carriage of rmpA, iutC, and ybtA, the genes associated with hypervirulence, was significantly higher in the pks-positive isolates than the pks-negative isolates (95.5% vs. 13.2%, p < 0.001). Further studies to determine the presence of hypervirulent pks-bearing bacterial populations in the flora of community residents and their association with different disease entities may be warranted.

The Antimicrobial Susceptibility of Klebsiella pneumoniae from Community Settings in Taiwan, a Trend Analysis.

Drug-resistant Klebsiella pneumoniae, especially extended-spectrum ß-lactamase (ESBL)- and/or AmpC ß-lactamase-producing strains, is an emerging problem worldwide. However, few data focusing on drug susceptibility of K. pneumoniae from community is available. In this study, we analyzed 1016 K. pneumoniae isolates from outpatients or those visiting emergency rooms collected during 2002-2012 from Taiwan Surveillance of Antimicrobial Resistance program. Significantly decreased susceptibilities to 3rd generation cephalosporins and ciprofloxacin were found during the study period. By 2012, susceptibility to cefotaxime and ciprofloxacin was 83.6% and 81.6%, respectively. The prevalence of ESBL-producers increased from 4.8% in 2002 to 11.9% in 2012 (P = 0.012), while that of AmpC ß-lactamase-producers increased from 0% to 9.5% in the same period (P < 0.001). Phylogenic analysis of the ESBL and AmpC-ß-lactamase-producers by pulsed-field gel electrophoresis and multi-locus sequence typing revealed wide genetic diversity even among the most common sequence type 11 isolates (33.0%). By multivariate analysis, later study year, elderly, and urine isolates were associated with carriage of ESBL genes, while only urine isolates were associated with carriage of AmpC ß-lactamase genes. Further studies are needed to determine which antibiotics are reasonable empirical therapy options for patients presenting with severe sepsis that might be caused by K. pneumoniae.

Antimicrobial Non-Susceptibility of Escherichia coli from Outpatients and Patients Visiting Emergency Rooms in Taiwan.

Longitudinal nationwide surveillance data on antimicrobial non-susceptibility and prevalence of extended-spectrum ß-lactamases (ESBLs) as well as AmpC ß-lactamases producers among Escherichia coli from different sources in the community settings are limited. Such data may impact treatment practice. The present study investigated E. coli from outpatients and patients visiting emergency rooms collected by the Taiwan Surveillance of Antimicrobial Resistance (TSAR) program. A total of 3481 E. coli isolates were studied, including 2153 (61.9%) from urine and 1125 (32.3%) from blood samples. These isolates were collected biennially between 2002 and 2012 from a total of 28 hospitals located in different geographic regions of Taiwan. Minimum inhibitory concentrations (MIC) were determined using methods recommended by the Clinical Laboratory Standards Institute (CLSI). The prevalence and factors associated with the presence of ESBL and AmpC ß-lactamase-producers were determined. Significant increases in non-susceptibility to most ß-lactams and ciprofloxacin occurred during the study period. By 2012, non-susceptibility to cefotaxime and ciprofloxacin reached 21.1% and 26.9%, respectively. The prevalence of ESBL- and AmpC- producers also increased from 4.0% and 5.3%, respectively, in 2002-2004, to 10.7% for both in 2010-2012 (P < 0.001). The predominant ESBL and AmpC ß-lactamase genes were CTX-M and CMY-types, respectively. Non-susceptibility of urine isolates to nitrofurantoin remained at around 8% and to fosfomycin was low (0.7%) but to cefazolin (based on the 2014 CLSI urine criteria) increased from 11.5% in 2002-2004 to 23.9% in 2010-2012 (P <0.001). Non-susceptibility of isolates from different specimen types was generally similar, but isolates from elderly patients were significantly more resistant to most antimicrobial agents and associated with the presence of ESBL- and AmpC- ß-lactamases. An additional concern is that decreased ciprofloxacin susceptibility (MIC 0.12-1 mg/L) was as high as 25% in isolates from all age groups, including those from pediatric patients. Our data indicated that there is a need to re-evaluate appropriate treatment selection for community-acquired infections in Taiwan. Identification of community reservoirs of multidrug-resistant E. coli is also warranted.

Antimicrobial susceptibilities of Proteus mirabilis: a longitudinal nationwide study from the Taiwan surveillance of antimicrobial resistance (TSAR) program.

BACKGROUND: Longitudinal nationwide data on antimicrobial susceptibility in Proteus mirabilis from different sources are rare. The effects of the revised Clinical and Laboratory Standards Institute (CLSI) ß-lactam breakpoints on susceptibility rates and on detecting extended-spectrum ß-lactamase (ESBL) and AmpC ß-lactamase-producers in this species are also seldom evaluated. The present study analyzed data from the Taiwan Surveillance of Antimicrobial Resistance program to address these issues. METHODS: Isolates were collected biennially between 2002 and 2012 from 25 to 28 hospitals in Taiwan. Minimum inhibitory concentrations (MIC) were determined by reference broth microdilution method. All isolates with aztreonam, ceftazidime, or cefotaxime MIC ≥ 2 mg/L were checked for the presence of ESBL by CLSI confirmatory test and subjected to ESBL and AmpC ß-lactamases gene detection by PCR. Univariate and multivariate analyses were performed. RESULTS: Between 2002 and 2012, a total of 1157 P. mirabilis were studied. Susceptibility to cefotaxime, ceftazidime, and ciprofloxacin decreased significantly during the past decade, from 92.6% to 81.7%, 100% to 95.2%, and 80.1% to 53.8%, respectively (P < 0.01). The revised CLSI breakpoints had significant impact on susceptibility to cefazolin (2009 vs. current breakpoints, 71.9% vs. 0.9%) and imipenem (99.8% vs. 55.1%) (P < 0.001 for both). However, using the 2014 cefazolin breakpoints for urinary tract infections, 81.2% of the urine isolates were susceptible. Susceptibilities of isolates from different specimen types were mostly similar but outpatient isolates were more susceptible than inpatient isolates. The overall prevalence of ESBL- and AmpC- producers was 8.2% and 4.7%, respectively, but AmpC carriage increased significantly over the years (from 0 to 7.0%, P < 0.001). ESBL and AmpC ß-lactamase-producers were more likely to be found in elderly and ICU patients. The predominant ESBL and AmpC ß-lactamase genes were CTX-M- and CMY- types, respectively. CONCLUSIONS: A significant decrease in susceptibility to 3rd-generation cephalosporins and ciprofloxacin occurred in P. mirabilis from Taiwan in the past decade. The prevalence of ESBL remained stable but AmpC ß-lactamase-producing P. mirabilis increased significantly. Cefotaxime was a better surrogate than ceftazidime for predicting the presence of these ß-lactamases. Continuous surveillance on antimicrobial resistance and associated resistance mechanisms in P. mirabilis is warranted.

Levofloxacin-resistant haemophilus influenzae, Taiwan, 2004-2010.

Levofloxacin resistance in Haemophilus influenzae has increased significantly in Taiwan, from 2.0% in 2004 to 24.3% in 2010 (p<0.001). Clinical and molecular investigations of 182 levofloxacin-resistant isolates revealed that the increase was mainly the result of the spread of several clones in the elderly population in different regions.

Epidemiology and molecular characterization of macrolide-resistant Streptococcus pyogenes in Taiwan.

Our multicenter nationwide surveillance data indicated that erythromycin (ERY) resistance among group A Streptococcus (GAS) isolates in Taiwan declined from 53.1% in 1998 and 2000 to 14.6% in 2002 and 2004 and 10.7% in 2006 to 2010 (P < 0.01). The present study aimed to assess the epidemiology of GAS in Taiwan and identify factors associated with ERY resistance. All 127 ERY-resistant (ERY(r)) isolates and 128 randomly selected ERY-susceptible (ERY(s)) isolates recovered from 1998 to 2010 were emm typed. ERY(r) isolates were also characterized by ERY resistance phenotype and mechanisms and pulsed-field gel electrophoresis (PFGE). Multilocus sequence typing was performed on selected ERY(r) isolates. The predominant emm types in ERY(r) isolates were emm22 (n = 33, 26.0%), emm12 (n = 24, 18.9%), emm4 (n = 21, 16.5%), and emm106 (n = 15, 11.8%). In ERY(s) isolates, emm12 (n = 27, 21.9%), emm1 (n = 18, 14.1%), emm106 (n = 16, 12.5%), and emm11 (n = 9, 7.1%) predominated. The most common ERY resistance phenotype was the M phenotype (resistant to macrolides) (70.9%), with all but one isolate carrying mef(A), followed by the constitutive macrolide-lincosamide-streptogramin B resistance (cMLSB) phenotype (26.8%), with isolates carrying erm(B) or erm(TR). ERY(r) isolates of the emm12-sequence type 36 (ST36) lineage with the cMLSB phenotype were mostly present before 2004, while those of the emm22-ST46 lineage with the M phenotype predominated in later years. Recovery from respiratory (throat swab) specimens was an independent factor associated with ERY resistance. emm1 and emm11 GAS isolates were significantly associated with ERY(s), while emm22 was detected only in ERY(r) GAS. In addition, emm106 isolates were prevalent among the abscess/pus isolates, whereas emm12 isolates were strongly associated with a respiratory (throat) origin. In addition to identifying factors associated with ERY resistance in GAS, our study provides helpful information on the changing GAS epidemiology in Taiwan.

Complete sequences of two plasmids in a blaNDM-1-positive Klebsiella oxytoca isolate from Taiwan.

Genetic determinants of a bla(NDM-1)-positive, multidrug-resistant bacterial isolate that caused active infection was investigated by DNA sequencing. Two plasmids, pKOX_NDM1 and pKOX-R1, were identified for the Klebsiella oxytoca strain E718. Sequence annotation revealed a bla(NDM-1) gene in pKOX_NDM1 and two extended-spectrum ß-lactamase producers (bla(CTX-M-3) and blaSHV-12) and a wide array of resistance genes in pKOX-R1. These findings highlight the difficulty in treating multidrug-resistant bacterial infections and the potential danger of emerging resistant enterobacteria.