The risk of pig and chicken farming for carriage and transmission of Escherichia coli containing extended-spectrum beta-lactamase (ESBL) and mobile colistin resistance (mcr) genes in Thailand.

South-East Asian countries report a high prevalence of extended-spectrum cephalosporin- (ESC-) and colistin-resistant Escherichia coli (Col-R-Ec). However, there are still few studies describing the molecular mechanisms and transmission dynamics of ESC-R-Ec and, especially, Col-R-Ec. This study aimed to evaluate the prevalence and transmission dynamics of Ec containing extended spectrum beta-lactamases (ESBL) and mobile colistin resistance (mcr) genes using a 'One Health' design in Thailand. The ESC-R-Ec and Col-R-Ec isolates of human stool samples (69 pig farmers, 155 chicken farmers, and 61 non-farmers), rectal swabs from animals (269 pigs and 318 chickens), and the intestinal contents of 196 rodents were investigated. Resistance mechanisms and transmission dynamics of Ec isolates (n=638) were studied using short and long read sequencing. We found higher rates of ESBL-Ec isolates among pig farmers (n=36; 52.2%) than among chicken farmers (n=58; 37.4 %; P<0.05) and the control group (n=61; 31.1 %; P<0.05). Ec with co-occurring ESBL and mcr genes were found in 17 (6.0 %), 50 (18.6 %) and 15 (4.7 %) samples from humans, pigs and chickens, respectively. We also identified 39 (13.7 %) human samples with non-identical Ec containing ESBL and mcr. We found higher rates of ESBL-Ec, in particular CTX-M-55, isolates among pig farmers than among non-pig farmers (P<0.01). 'Clonal' animal-human transmission of ESBL-Ec and Ec with mcr genes was identified but rare as we overall found a heterogenous population structure of Ec. The Col-R-Ec from human and animal samples often carried mcr-1.1 on conjugative IncX4 plasmids. The latter has been identified in Ec of many different clonal backgrounds.

One Health Surveillance of Antimicrobial Resistance Phenotypes in Selected Communities in Thailand.

Integrated surveillance of antimicrobial resistance (AMR) using the One Health approach that includes humans, animals, food, and the environment has been recommended by responsible international organizations. The objective of this study was to determine the prevalence of AMR phenotypes in Escherichia coli and Klebsiella species isolated from humans, pigs, chickens, and wild rodents in five communities in northern Thailand. Rectal swabs from 269 pigs and 318 chickens; intestinal contents of 196 wild rodents; and stool samples from 69 pig farmers, 155 chicken farmers, and 61 non-farmers were cultured for E. coli and Klebsiella species, which were then tested for resistance to ceftriaxone, colistin, and meropenem. The prevalence of ceftriaxone-resistant E. coli and Klebsiella species in pigs, chickens, rodents, pig farmers, chicken farmers, and non-farmers was 64.3%, 12.9%, 4.1%, 55.1%, 38.7%, and 36.1%, respectively. Colistin resistance in pigs, chickens, rodents, pig farmers, chicken farmers, and non-farmers was 41.3%, 9.8%, 4.6%, 34.8%, 31.6%, and 24.6%, respectively. Meropenem resistance was not detected. The observed high prevalence of AMR, especially colistin resistance, in study food animals/humans is worrisome. Further studies to identify factors that contribute to AMR, strengthened reinforcement of existing regulations on antimicrobial use, and more appropriate interventions to minimize AMR in communities are urgently needed.

Feasibility, Challenges, and Benefits of Global Antimicrobial Resistance Surveillance System Implementation: Results from a Multicenter Quasi-Experimental Study.

The Global Antimicrobial Resistance Surveillance System (GLASS) is one of the pillars of the global action plan on antimicrobial resistance launched by the World Health Organization in 2015. This study was conducted to determine the feasibility and benefits of GLASS as a component of antimicrobial stewardship strategies in three provincial hospitals in Thailand. Data on the types of bacteria isolated and their antibiotic susceptibility during January-December 2019 and January-April 2020 were retrieved from the microbiology laboratory of each participating hospital. Laboratory-based antibiograms from 2019 and GLASS-based antibiograms from 2020 were created and compared. A total of 14,877 and 3580 bacterial isolates were obtained during January-December 2019 and January-April 2020, respectively. The common bacteria isolated in both periods were Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Staphylococcus aureus. Hospital-acquired infection (HAI)-related bacteria were observed in 59.0%, whereas community-acquired infection (CAI)-related bacteria were observed in 41.0% of isolates. Antibiotic resistance in CAIs was high and may have been related to the misclassification of colonized bacteria as true pathogens and HAIs as CAIs. The results of this study on AMR surveillance using GLASS methodology may not be valid owing to several inadequate data collections and the problem of specimen contamination. Given these considerations, related personnel should receive additional training on the best practices in specimen collection and the management of AMR surveillance data using the GLASS approach.

A One Health approach to assessing occupational exposure to antimicrobial resistance in Thailand: The FarmResist project.

This Southeast Asia-Europe research project will use a One Health approach to identify the major parameters responsible for the presence of animal-associated antimicrobial resistant bacteria in animal production facilities in Thailand and the risk of their transmission from animals to humans. We will focus on traditional, small, extensive pig and poultry farms where information on antibiotic use is scarce and animals live in close contact with humans. This cross-sectional study will be based on the epidemiological analysis of the antimicrobial resistance (AMR) present in fecal samples from animals and humans. Extended spectrum beta-lactamase producing Enterobacteriaceae (ESBL-E) and Enterobacteriaceae resistant to colistin will be actively searched in the feces of farm animals (pigs and poultry), small wild rodents and farmers. Phenotypic (selective plating) and genotypic (multilocus seuquence typing and sequencing) methods will be used for the detection of AMR, the identification of antibiotic resistance genes (ARGs) and the characterization of strains carrying resistance genes. Questionnaires will be administered to investigate the effects of antibiotic use, farm characteristics and biosecurity measures on the occurrence of AMR in animals. Subsequently, the fecal carriage of AMR and ARGs in farmers will be compared to a control population with no occupational contacts with animals, thus enabling an estimation of the risk of transmission of AMR/ARGs from animals to farmers.

Case Report: Recovery of Pathogenic Leptospira spp. from Routine Aerobic Blood Culture Bottles.

Leptospira spp. are fastidious and slow-growing bacteria, making recovery difficult and diagnostic sensitivity in the clinical setting low. However, collection of Leptospira isolates is valuable for epidemiological and laboratory research. Severe leptospirosis cases may present as septic shock, and the differential diagnosis often includes bacterial septicemia, leading clinicians to collect blood cultures. Here, we report the successful isolation of pathogenic Leptospira spp. from blood culture bottles (targeting aerobic bacteria incubated at 37°C) from a 64-year-old man admitted with septic shock. The patient presented with 4 days of fever, severe hypotension, transient atrial fibrillation, jaundice, and oliguric renal failure. After admission, intravenous ceftriaxone plus azithromycin was given with fluid resuscitation, norepinephrine infusion, invasive mechanical ventilation, and renal replacement therapy. He was discharged from the hospital 16 days after admission. Using the blood sample obtained on admission, the diagnosis of leptospirosis was confirmed by multiplex real-time PCR (targeting bacterial 16S rRNA and LipL32 gene). We collected 200 µL from the blood culture bottle to inoculate a 5-mL Ellinghausen, McCullough, Johnson, and Harris media supplemented with 5% fetal bovine serum. After 2 weeks of incubation at 30°C, Leptospira strains were identified and confirmed by real-time PCR. Genotyping was undertaken using the multi-locus sequence typing (MLST) scheme#1. The isolate matched with ST50 isolates in the PUbMLST database. This case provides evidence that in tropical countries, severe leptospirosis should be considered in patients who present with symptoms of sepsis. Pathogenic Leptospira may be successfully isolated from aerobic blood cultures in routine clinical settings.

Contamination by Antibiotic-Resistant Bacteria in Selected Environments in Thailand.

This study determined the presence of important antibiotic-resistant bacteria in selected environments in Thailand, including wastewater samples from 60 hospitals; washed fluid, leachate, flies, cockroaches, and rats collected from five open markets; washed fluid from garbage trucks; and stabilized leachate from a landfill facility. At least one type of antibiotic-resistant bacteria was isolated from all samples of influent fluid before treatment in hospitals, from wastewater treatment tank content in hospitals, and from 15% of effluent fluid samples after treatment with chlorine prior to draining it into a public water source. Antibiotic-resistant bacteria were recovered from 80% of washed market fluid samples, 60% of market leachate samples, all fly samples, 80% of cockroach samples, and all samples of intestinal content of rats collected from the open markets. Antibiotic-resistant bacteria were recovered from all samples from the landfill. Extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli and/or Klebsiella pneumoniae were the most common antibiotic-resistant bacteria recovered from all types of samples, followed by carbapenem-resistant E. coli and/or K. pneumoniae. Colistin-resistant Enterobacteriaceae, carbapenem-resistant Psuedomonas aeruginosa, carbapenem-resistant Acinetobacter baumannii, colistin-resistant Enterobacteriaceae, vancomycin-resistant Enterococci, and methicillin-resistant S. aureus were less common. These findings suggest extensive contamination by antibiotic-resistant bacteria in hospital and community environment in Thailand.

Evaluation of the Rapid Polymyxin NP test for detection of colistin susceptibility in Enterobacteriaceae isolated from Thai patients.

Development and evaluations of the Rapid Polymyxin NP test for detection of colistin resistance in Enterobacteriaceae have been recently reported. In this study, we evaluated the performance of the test using a larger number of Enterobacteriaceae, and a larger proportion of isolates with a colistin MIC close to the breakpoint. Out of 339 isolates, the Rapid Polymyxin NP test detected colistin resistance in 13 isolates of Escherichia coli, 213 isolates of Klebsiella pneumoniae, 9 isolates of Enterobacter aerogenes, and 10 isolates of the other Enterobacteriaceae species. Sensitivity and specificity of the test for detecting colistin resistance were 100% and 95.9%, respectively. Positive predictive value and negative predictive value were 98.3% and 100%, respectively.

Prevalence of the colistin resistance gene mcr-1 in colistin-resistant Escherichia coli and Klebsiella pneumoniae isolated from humans in Thailand.

OBJECTIVES: Historically, colistin has been considered a last-line therapeutic option against multidrug-resistant Gram-negative bacterial infections. However, chromosomally-encoded and plasmid-mediated colistin resistance is increasingly being reported worldwide. Spread of the plasmid-borne colistin resistance gene mcr-1 is of great concern since it can be transferred between bacteria. The aim of this study was to investigate the prevalence of mcr-1 in Escherichia coli and Klebsiella pneumoniae collected from human clinical specimens in Thailand during 2014-2017. METHODS: Minimum inhibitory concentrations (MICs) of colistin were determined by the broth microdilution method for 317 non-duplicate Enterobacteriaceae clinical isolates (37 E. coli and 280 K. pneumoniae). All isolates were screened for the mcr-1 gene by PCR. RESULTS: The colistin MIC50, MIC90 and MIC range for the 37 E. coli isolates were 0.5, 8 and 0.5-32mg/L, respectively. The mcr-1 gene was detected in 11 E. coli isolates (29.7%). Escherichia coli harbouring the mcr-1 gene had a colistin MIC range of 4-32mg/L. The colistin MIC50, MIC90, and MIC range for the 280 K. pneumoniae isolates were 32, >128, and 0.25 to >128mg/L, respectively. The mcr-1 gene was detected in 4 K. pneumoniae isolates (1.4%). Klebsiella pneumoniae harbouring the mcr-1 gene had a colistin MIC range of 4-64mg/L. CONCLUSIONS: This is the first report on the prevalence of the mcr-1 gene in colistin-resistant E. coli and K. pneumoniae isolated from humans in Thailand. These data provide added insight into the mechanism of colistin resistance among Enterobacteriaceae pathogens.

Thailand Antimicrobial Resistance Containment and Prevention Program.

The Thailand Antimicrobial Resistance (AMR) Containment and Prevention Program was founded to develop, co-ordinate and implement AMR Containment and Prevention (AMRCP) operational actions in Thailand following the 'One Health' approach. This article summarises the ten AMRCP operational actions initiated during the initial phase of the programme from 2012 to 2016: estimating the national AMR burden; establishing the dynamics of AMR chains to understand how AMR in Thailand develops and spreads; developing a national AMRCP infrastructure; developing laboratory and information technology systems for surveillance of AMR, antibiotic use and hospital-acquired infections; regulating the use and distribution of antibiotics in humans and food animals; generating local evidence for promoting responsible use of antibiotics and efficient practices for infection prevention and control; designing AMRCP campaigns; creating an AMRCP package; implementing the AMRCP package in selected pilot communities; and conducting research and development on diagnostics, therapy and prevention of antimicrobial-resistant bacterial infections. The programme's core campaign is to stop producing AMR by promoting responsible use of antibiotics, and to stop the acquisition and transmission of AMR by promoting good sanitation and hygiene as well as compliance with infection control and prevention practices.

Prevalence of antibiotic resistant bacteria in healthy adults, foods, food animals, and the environment in selected areas in Thailand.

OBJECTIVES: The aim of this study was to determine the prevalence of antibiotic-resistant bacteria, especially extended-spectrum beta-lactamase (ESBL) producing Escherichia coli, in samples from healthy adults, foods, food animals, and the environment in selected areas of Thailand. METHODS: Samples were collected from stool specimens from adult food factory and food animal farm workers, fresh and cooked foods sold at markets, rectal swabs of healthy pigs and chickens, fresh pork meat from slaughterhouses, water samples from canals as well as fish and shrimp farm ponds, and stagnant water sources on pig farms. Antibiotic susceptibility was determined using the disk diffusion or agar dilution methods. Extended-spectrum beta-lactamase production was assayed using a double disk diffusion method. RESULTS: Among 544 healthy adult food factory workers, 75·5% were positive for ESBL producing E. coli, while 77·3% of E. coli isolated from 30 healthy animal farm workers were positive. Amongst healthy food animals, ESBL producing status among E. coli isolates were more commonly detected in pigs (76·7%) than broilers (40%). Extended-spectrum beta-lactamase producing E. coli seemed to be more prevalent in fresh meat samples than in fresh vegetables, in fresh foods than in cooked foods, and in water samples collected from the animal farms than those from canals and fish and shrimp ponds. CONCLUSIONS: Extended-spectrum beta-lactamase producing E. coli isolates are prevalent amongst healthy individuals, foods along the food production chain from farms to consumers, and in the environment in selected areas in Thailand.

In vitro activity of colistin plus sulbactam against extensive-drug-resistant Acinetobacter baumannii by checkerboard method.

OBJECTIVE: To determine in vitro activity of colistin plus sulbactam against extensive-drug-resistant (XDR) Acinetobacter baumannii. MATERIAL AND METHOD: Checkerboard method was used to determine in vitro activity of colistin plus sulbactam against 11 clinical isolates of XDR A. baumannii. The concentrations of colistin and sulbactam used in the study were 0.025 to 128 mg/ 1 and 4 to 256 mg/l, respectively. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of colistin, sulbactam and colistin plus sulbactam at various concentrations were determined. Fractional inhibitory concentration index (FICI) was calculated. The antibiotic combination is considered synergistic if FICI < 0.5, indifferent if FICI 0.5 to 4.0, and antagonistic if FICI > 4.0. RESULTS: Ten isolates of XDR A. baumannii were susceptible to colistin (MIC < 2 mg/l) and one isolate was resistant to colistin (MIC 8 mg/l). There were no antagonistic effects of colistin plus sulbactam against all study isolates. For 10 isolates of colistin-susceptible XDR A. baumannii, some MIC values of the combinations were lower than those of single antibiotics. However no synergistic effect of colistin and sulbactam was observed in colistin-susceptible XDR A. baumannii isolates. The synergistic effect of colistin and sulbactam was detected in some concentrations of colistin and sulbactam against colistin-resistant XDR A. baumannii isolate. CONCLUSION: The combination of colistin and sulbactam showed an indifferent effect against colistin-susceptible XDR A. baumannii. The combination of colistin and sulbactam showed synergistic effect at some concentrations of colistin and sulbactam against a clinical isolate of colistin-resistant XDR A. baumannii. In vitro time-kill method should be performed to confirm the aforementioned observations.

In vitro susceptibility test of sitafloxacin against resistant gram-negative bacilli isolated from Thai patients by disk diffusion method.

OBJECTIVE: To determine a correlation of minimum inhibitory concentration (MIC) of sitafloxacin determined by agar dilution method with inhibition zone diameter of sitafloxacin determined by disk diffusion method, and to determine inhibition zone, diameter breakpoints of sitafloxacin against resistant gram-negative bacilli isolated from Thai patients. MATERIAL AND METHOD: The study bacteria were 332 clinical isolates of gram-negative bacilli including ESBL-producing E. coli, ESBL-producing K. pneumoniae, P. aeruginosa andA. baumannii. Each isolate of the present study bacteria was tested for minimum inhibitory concentration (MIC) of sitafloxacin by agar dilution method and inhibition zone diameter of sitafloxacin by disk diffusion method. RESULTS: The MICs and inhibition zone diameters of sitafloxacin against gram-negative bacilli were well correlated (correlation coefficient -0.926, p-value < 0.001). The inhibition zone diameter > or = 15 mm had the least total error for determining susceptibility to sitafloxacin based on MIC value of sitafloxacin but the inhibition zone diameter > or = 16 mm had less false susceptibility than that of > or = 15 mm when compared with sitafloxacin MIC < or = 2 mg/l that was considered susceptible. The inhibition zone diameter > or = 19 mm had the least total error for determining susceptibility to sitafloxacin based on MIC value of sitafloxacin but the inhibition zone diameter > or = 18 mm had less false susceptibility than that of > or = 19 mm when compared with sitafloxacin MIC < or = 1 mg/l that was considered susceptible. CONCLUSION: For the susceptibility test of sitafloxacin against resistant gram-negative bacilli by disk diffusion method, the inhibition zone diameter > or = 16 mm and > or = 18 mm seem to be the appropriate breakpoints for susceptibility for resistant gram-negative bacilli isolated from urine and blood, respectively, since the serum concentration of sitafloxacin is rather low whereas the urinary concentration of sitafloxacin is much higher.

In vitro and in vivo activity of tebipenem against ESBL-producing E. coli.

OBJECTIVE: To determine in vitro and in vivo activity of tebipenem against ESBL-producing E. coli. MATERIAL AND METHOD: Minimum inhibitory concentration (MIC) of tebipenem against 100 clinical isolates of ESBL-producing E. coli was performed by broth micro-dilution technique. Blood and urine samples from 10 healthy male subjects before and after receiving 300 mg of tebipenem pivoxil 3 times a day for 2 consecutive days were determined for inhibitory and bactericidal titers against a clinical urinary isolate of ESBL-producing E. coli by disk diffusion method and broth micro- dilution method. RESULTS: MIC50 and MC90 of tebipenem against ESBL-producing E. coli were both 0.06 mg/L with MIC range from ≤ 0.06 to 0.25 mg/L. The inhibition zones were observed around the disks inoculated with serum samples and urine samples collected from all study subjects after receiving tebipenem pivoxil for at least 1 hour and 5 hours, respectively. The inhibitory titer of 1:160 and bactericidal titer of 1:160 of serum samples were observed for at least one hour after ingestion of tebipenem pivoxil. Inhibitory titer of 1:640 and bactericidal titer of 1:640 of urine samples were observed after at least 14 hours after ingestion of tebipenem pivoxil. No subjects experienced side effects related to receiving tebipenem pivoxil. CONCLUSION: Tebipenem is very active against ESBL-producing E. coli. Oral administration of tebipenem pivoxil 300 mg 3 times a day for two days was well tolerated, safe and induced high inhibitory and bactericidal activity in serum and urine. Tebipenem pivoxil could be an oral agent for effective therapy of ESBL-producing E. coli infections.

In vitro activity of polymyxin B against carbapenem-resistant Acinetobacter baumannii.

OBJECTIVE: To determine in vitro activity of polymyxin B against carbapenem-resistant Acinetobacter baumannii. MATERIAL AND METHOD: The activity of polymyxin B was determined against 217 strains of carbapenem-resistant A. baumannii collected from different patients by standard agar dilution method and disk diffusion test using polymyxin B disk (300 units). The control strains were E. coli ATCC 25922 and P. aeruginosa ATCC 27853. RESULTS: The MIC values and inhibition zone diameters of polymyxin B against the quality control bacteria were within the acceptable range. The MIC50 and MIC90 values of polymyxin B against 217 strains of carbapenem-resistant A. baumannii were 0.5 and 1 mg/l, respectively. If the susceptible MIC breakpoint of polymyxin B was ≤ 2 mg/l, 98.2% of carbapenem-resistant A. baumannii strains were susceptible to polymyxin B. If the susceptible MIC breakpoint of polymyxin B was ≤ 2 mg/l, the sensitivity and the specificity ofthe inhibition zone diameter of > 12 mm were 100% and 75%, respectively. The aforementioned diagnostic parameters gave positive predictive value of 99.5% and negative predictive value of 100% for predicting susceptibility of carbapenem-resistant A. baumannii to polymyxin B by disk diffusion test. CONCLUSION: Polymyxin B was very active against carbapenem-resistant A. baumannii. The inhibition zone diameters of >12 mm was accurate enough to determine susceptibility of carbapenem-resistant A. baumannii topolymyxin B. Polymyxin B can be an alternative to or more preferable than colistin for therapy ofcarbapenem-resistant A. baumannii infections.

Inhibitory activity of fermented milk with Lactobacillus casei strain Shirota against common multidrug-resistant bacteria causing hospital-acquired infections.

OBJECTIVE: To determine inhibitory activity of fermented milk with Lactobacillus casei strain Shirota (FMLC) against common multi-drug-resistant (MDR) bacteria causing hospital-acquired infections. MATERIAL AND METHOD: Time-kill methods of FMLC and cell-free filtered fluid of FMLC (CF-FMLC) against Acinetobacter baumannii, Pseudomonas aeruginosa, ESBL-producing Escherichia coli & Klebsiella pneumoniae and methicillin-resistant Staphylococcus aureus were conducted. The control solutions were Mueller Hinton broth (MHB) and distilled water. The mixtures of FMLC, CF-FMLC, MHB and DW with 10(5) to 10(6) CFU/ml of each bacterium were prepared and incubated at 35 degrees C. Each mixture was quantified for viable bacteria at 0, 1, 3, 6 and 24 hr after incubation onto brain heart infusion agar plates. The inoculated agar plates were incubated at 35 degrees C for 24-48 hr. Bacterial colonies on agar plates were counted and compared among the mixtures. RESULTS: Log CFUs of each organism in MHB and distilled water after incubation were increased from 5.1-6.3 at 0 h to 6.4- > 11 at 24 hr. Log CFUs of each organism in FMLC and CF-FMLC after incubation with study bacteria for 0, 1, 3, 6 and 24 hr were decreased to undetectable amounts at 24 hr. CONCLUSION: FMLC and CF-FMLC exerted slow inhibitory activity against MDR bacteria resulting in eradication of all study bacteria at 24 hr. Such inhibitory effects were probably due to the products of the milk fermented by Lactobacillus casei strain Shirota. Clinical study is needed to determine if consumption of FMLC can prevent and treat colonization and infection with MDR bacteria in hospitalized patients.

Comparative in vitro activity of sitafloxacin against bacteria isolated from Thai patients with urinary tract infections and lower respiratory tract infections.

OBJECTIVE: To determine comparative in vitro activity of sitafloxacin against clinical isolates of bacteria from Thai patients with urinary tract infection and those with lower respiratory tract infection. MATERIAL AND METHOD: 1,255 clinical isolates of Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa, Acinetobacter baumannii, Enterococcus spp, Streptococcus pneumoniae, Staphylococcus aureus, Haemophilus influenzae and Moraxella catarrhalis isolated from different Thai patients with urinary tract infection and those with lower respiratory tract infection in 2010 were included. The minimum inhibitory concentrations (MICs) of sitafloxacin, ciprofloxacin, levofloxacin, moxifloxacin, imipenem, amikacin, ampicillin, ceftazidime, ceftriaxone, penicillin, piperacillin/tazobactam, vancomycin, azithromycin and trimethoprim/sulfamethoxazole were determined by standard agar dilution method. RESULTS: The MIC50 and MIC90 values of sitafloxacin against all tested bacteria were lowest when compared with those of levofloxacin, ciprofloxacin and moxifloxacin. Sitafloxacin was active against 51% of methicillin-resistant S. aureus (MRSA) isolates. The activity of sitafloxacin against multidrug-resistant (MDR) Gram-negative bacteria, such as, extended spectrum beta-lactamase (ESBL)-producing E. coli and K. pneumomiae, P. aeruginosa and A. baumannii was comparable to or more than that of some beta-lactam/beta-lactamase inhibitors, cephalosporins or carbapenems. CONCLUSION: Sitafloxacin is more active than levofloxacin, ciprofloxacin and moxifloxacin against isolated bacteria from Thai patients with urinary tract and lower respiratory infections including antibiotic resistant bacteria, such as MRSA, ESBL-producing Gram-negatives, carbapenem-resistant A. baumannii.

Viability of Lactobacillus casei strain Shirota (LcS) from feces of Thai healthy subjects regularly taking milk product containing LcS.

OBJECTIVE: To demonstrate the recovery of Lactobacillus casei strain Shirota (LcS) from feces of Thai subjects who regularly took LcS containing milk product for 1 week and demonstrate the disappearance of LcS after stopped taking milk product. MATERIAL AND METHOD: First fecal samples were collected from 20 healthy adults at 10 days after they abstained from all lactobacillus containing milk products. Second specimens taken after the subjects ingested LcS containing milk product for 7 days and third specimens at 7 days after they stopped taking LcS containing milk product. All the fecal specimens were culture for LcS using LLV-FOS culture medium and enumeration of LcS was calculated. All stool samples were also tested for the presence of LcS by using nested PCR to confirm the presence of LcS obtained from culture method. RESULTS: Both culture and nested PCR method showed that all the stools samples obtained from subjects prior to the administration of LcS containing milk product were devoid of LcS, except for 3 specimens which showed weakly positive test for PCR. At 7 days after ingesting LcS containing milk product, all stool specimens were positive for LcS on both culture and PCR method. At 7 days after stopped taking LcS containing milk product, 1/19 specimens were positive from culture and 6/ 19 specimens were positive for PCR method. CONCLUSION: LcS could survive in the gastrointestinal tract of Thai subjects and could be recovered from the feces after ingestion.