BACKGROUND: Campylobacter jejuni is an important food-borne pathogen that causes human gastroenteritis. This study was conducted to investigate the incidence of isolation, antimicrobial susceptibility pattern, and C. jejuni genotype from diarrhea patients in Busan, Korea. METHODS: A total of 97 C. jejuni were isolated from diarrhea patients during five food-borne outbreaks from 2014 to September 2017. Antimicrobial susceptibility tests were carried out by the broth microdilution method for ciprofloxacin (CIP), nalidixic acid (NAL), tetracycline (TET), chloramphenicol, azithromycin (AZI), erythromycin (ERY), streptomycin (STR), gentamicin, and telithromycin. To investigate C. jejuni genotypes, pulsed-field gel electrophoresis (PFGE) profile analysis was performed. RESULTS: The isolation rate of C. jejuni was 2.0% for the last 4 years and increased annually. Antimicrobial resistance rates of C. jejuni were shown to be in the order of NAL (90.9%), CIP (89.4%), TET (13.6%), AZI (3.0%), ERY (3.0%), and STR (1.5%). The proportion of multidrug-resistance was 18.2%, and they commonly contained quinolones (CIP-NAL). Analysis of PFGE patterns of SmaI-restricted DNA of C. jejuni isolates showed 17 clusters; cluster 11 was the major genotype pattern. CONCLUSION: This study will provide useful data for the proper use of antimicrobials and the management of resistant C. jejuni. Also it will help to provide data for the epidemiological investigation of foodborne diseases caused by C. jejuni, which is expected to increase in the future.
Azithromycin ; Busan ; Campylobacter jejuni ; Campylobacter ; Chloramphenicol ; Ciprofloxacin ; Diarrhea ; Disease Outbreaks ; DNA ; Electrophoresis, Gel, Pulsed-Field ; Erythromycin ; Foodborne Diseases ; Gastroenteritis ; Genotype ; Gentamicins ; Humans ; Incidence ; Korea ; Methods ; Nalidixic Acid ; Quinolones ; Streptomycin ; Tetracycline

Turtle-borne Salmonella enterica owns significance as a leading cause in human salmonellosis. The current study aimed to determine the quinolone susceptibility and the genetic characteristics of 21 strains of S. enterica subsp. enterica isolated from pet turtles. Susceptibility of four antimicrobials including nalidixic acid, ciprofloxacin, ofloxacin, and levofloxacin was examined in disk diffusion and MIC tests where the majority of the isolates were susceptible to all tested quinolones. In genetic characterization, none of the isolates were positive for qnr or aac(6')-Ib genes and no any target site mutations could be detected in gyrA, gyrB, and parC quinolone resistance determining regions (QRDR). In addition, neighbor-joining phylogenetic tree derived using gyrA gene sequences exhibited two distinct clads comprising; first, current study isolates, and second, quinolone-resistant isolates of human and animal origin. All results suggest that studied strains of S. enterica subsp. enterica isolated from pet turtles are susceptible to quinolones and genetically more conserved with regards to gyrA gene region.
Animals ; Ciprofloxacin ; Diffusion ; Humans ; Levofloxacin ; Nalidixic Acid ; Ofloxacin ; Quinolones ; Salmonella enterica* ; Salmonella Infections ; Salmonella* ; Trees ; Turtles*

The present study investigated the prevalence and mechanisms of fluoroquinolone (FQ)/quinolone (Q) resistance in Escherichia (E.) coli isolates from companion animals, pet-owners, and non-pet-owners. A total of 63 E. coli isolates were collected from 104 anal swab samples, and 27 nalidixic acid (NA)-resistant isolates were identified. Of those, 10 showed ciprofloxacin (CIP) resistance. A plasmid-mediated Q resistance gene was detected in one isolate. Increased efflux pump activity, as measured by organic solvent tolerance assay, was detected in 18 NA-resistant isolates (66.7%), but was not correlated with an increase in minimum inhibitory concentration (MIC). Target gene mutations in Q resistance-determining regions (QRDRs) were the main cause of (FQ)Q resistance in E. coli. Point mutations in QRDRs were detected in all NA-resistant isolates, and the number of mutations was strongly correlated with increased MIC (R = 0.878 for NA and 0.954 for CIP). All CIP-resistant isolates (n = 10) had double mutations in the gyrA gene, with additional mutations in parC and parE. Interestingly, (FQ)Q resistance mechanisms in isolates from companion animals were the same as those in humans. Therefore, prudent use of (FQ)Q in veterinary medicine is warranted to prevent the dissemination of (FQ)Q-resistant bacteria from animals to humans.
Animals ; Bacteria ; Ciprofloxacin ; Drug Resistance, Microbial ; Escherichia coli* ; Escherichia* ; Fluoroquinolones ; Friends* ; Humans ; Microbial Sensitivity Tests ; Nalidixic Acid ; Pets* ; Point Mutation ; Prevalence ; Quinolones ; Veterinary Medicine

OBJECTIVES: Few long-term studies have been conducted on the serotype and antibiotic resistance patterns of Salmonella speices (spp.) The aim of this study was to determine the serotypes and antibiotic resistance patterns of Salmonella spp. isolated at Jeollanam-do in Korea from 2004 to 2014. METHODS: A total of 276 Salmonella samples were evaluated. Serotyping was carried out according to the Kauffmann–White scheme. Antibiotic susceptibility was determined using the Vitek II system with an AST-N169 card. RESULTS: A total of 22 different serotypes were identified, and the major serotypes were Salmonella Enteritidis (116 strains, 42.0%) and Salmonella Typhimurium (60 strains, 21.7%). The highest resistance was observed in response to nalidixic acid (43.4%), followed by ampicillin (40.5%) and tetracycline (31.6%). Resistance to nalidixic acid was detected in 81.0% of S. Enteritidis. Multidrug resistance was detected in 43.3% of Salmonella spp. S. Enteritidis and S. Typhimurium presented the highest resistance (98.3%) and multidrug resistance rate (73.3%), respectively. The most highly observed antibiotic resistance pattern among Salmonella spp. in this study was ampicillin-chloramphenicol (14 strains, 5.7%). CONCLUSION: Overall, S. Enteritidis and S. Typhimurium showed higher antibiotic resistance than the other Salmonella serotypes tested in this study. Our study will provide useful information for investigating the sources of Salmonella infections, as well as selecting effective antibiotics for treatment.
Ampicillin ; Anti-Bacterial Agents ; Drug Resistance, Microbial* ; Drug Resistance, Multiple ; Jeollanam-do* ; Korea* ; Nalidixic Acid ; Salmonella enteritidis ; Salmonella Infections ; Salmonella typhimurium ; Salmonella* ; Serogroup* ; Serotyping ; Tetracycline

A novel Helicobacter species was identified from the gastrointestinal tract of the Korean striped field mouse (Apodemus agrarius). Biochemical testing, ultrastructure characterization, and 16S rRNA gene sequence analysis suggested that this bacterium represents a distinct taxon. The bacterium was positive for urease activity, susceptible to cephalothin and nalidixic acid, and weakly positive for oxidase and catalase activity. Electron microscopy revealed that the bacterium has spirally curved rod morphology with singular bipolar nonsheathed flagella. Genotypically, the isolated bacterial strains (YMRC 000215, YMRC 000216, and YMRC 000419) were most closely related to a reference strain of Helicobacter mesocricetorum (97.25%, 97.32%, and 97.03% 16S rRNA sequence similarities, respectively). The 16S rRNA sequences of these strains were deposited into GenBank under accession numbers AF284754, AY009129, and AY009130, respectively. We propose the name Helicobacter apodemus for this novel species.
Animals ; Catalase ; Cephalothin ; Databases, Nucleic Acid ; Flagella ; Gastrointestinal Tract* ; Genes, rRNA ; Helicobacter* ; Korea* ; Mice* ; Microscopy, Electron ; Murinae* ; Nalidixic Acid ; Oxidoreductases ; Sequence Analysis ; Urease

Infection with nontyphoidal Salmonella most often results in self-limited acute gastroenteritis. However, occasionally it causes bacteremia and localized infection requiring antibiotic treatment. A third-generation cephalosporin or fluoroquinolone is often the first choice of antibiotic. However, there has been an increase in nalidixic-acid-resistant nontyphoidal Salmonella with decreased fluoroquinolone susceptibility. Although there have been many cases reported of nontyphoidal Salmonella, no cases of nalidixic-acid-resistant nontyphoidal Salmonella have been reported in Korea. Here, we report on the case of a 61-year-old man with a diagnosis of acute osteomyelitis and periosteal abscess of the femur caused by nalidixic-acid-resistant Salmonella enteritidis. He was treated successfully with prolonged administration of a high-dose of ciprofloxacin and drainage of the abscess.
Abscess ; Bacteremia ; Ciprofloxacin ; Diagnosis ; Drainage ; Drug Resistance ; Femur* ; Gastroenteritis ; Humans ; Korea ; Middle Aged ; Nalidixic Acid ; Osteomyelitis* ; Salmonella ; Salmonella enteritidis*

To develop a live vaccine strain against fowl typhoid and paratyphoid caused by Salmonella serovar Gallinarum biovar Gallinarum (Salmonella Gallinarum) and Salmonella serovar Enteritidis (Salmonella Enteritidis), respectively, several nalidixic acid resistant mutants were selected from lipopolysaccharide (LPS) rough strains of Salmonella Gallinarum that escaped from fatal infection of a LPS-binding lytic bacteriophage. A non-virulent and immunogenic vaccine strain of Salmonella Gallinarum, SR2-N6, was established through in vivo pathogenicity and protection efficacy tests. SR2-N6 was highly protective against Salmonella Gallinarum and Salmonella Enteritidis and safer than Salmonella Gallinarum vaccine strain SG 9R in the condition of protein-energy malnutrition. Thus, SR2-N6 may be a safe and efficacious vaccine strain to prevent both fowl typhoid and paratyphoid.
Bacteriophages ; Nalidixic Acid ; Protein-Energy Malnutrition ; Salmonella ; Salmonella enteritidis ; Typhoid Fever* ; United Nations ; Virulence

OBJECTIVES: To determine the occurrence and antimicrobial resistance of pathogenic vibrios from green mussel, Perna viridis in bacoor bay cavite.

METHODS: Vibrios were isolated using TCBS agar and confirmed using API Identification kit. The relationship between the density of vibrios and environment parameters such as months, harvest sites and other physico-chemical parameters of water was determined. The isolated vibrios were subjected to antibiotic resistance testing to determine the resistance patterns.

RESULTS: Pathogenic vibrios were isolated in all of the 90 mussel samples. Of the 183 vibrio isolates, 75 strains were V. alginolyticus and 53 strains belonged to V. cholerae wherein 18 (34%) of these were V. cholerae serotype O1. Forty nine (49) strains belonged to V. parahaemolyticus and six were V. vulnificus. Using the regression analysis, salinity, water temperature and ph have significant correlation on the density of vibrios (p=0.0309), with regression model, total vibrios = -16990763 + 145858 Salinity + 186808 Temperature + 1037886 pH. In the antimicrobial resistance assay,ampicillin had the highest drug resistance (37.8%) followed by nalidixic acid (10.4%), tetracycline (10.4%) and co-trimoxazole (9.3%).

CONCLUSION: Pathogenic vibrios were isolated in mussel of Bacoor, Cavite and can be predicted using salinity, temperature and pH of the water. Thirty six percent (36%) of Vibrio isolates were resistance to ampicillin.

An antimicrobial susceptibility test was conducted to compare the resistance rates among Campylobacter spp. isolates from dogs (n = 50) raised under diverse conditions and humans (n = 50). More than 60% of Campylobacter (C.) jejuni from dogs and humans showed resistance to nalidixic acid, enrofloxacin and ciprofloxacin. C. jejuni isolates from humans showed higher resistance to tetracycline (83.3%) and ampicillin (91.3%) than those from dogs. None of the C. jejuni or Campylobacter coli isolates from humans or dogs were resistant to erythromycin. Overall, 85% of Campylobacter spp. isolates showed a multidrug resistant phenotype. Nucleotide sequencing analysis of the gryA gene showed that 100% of NA(R)/CIP(R) C. jejuni isolates from dogs and humans had the Thr-86th-Ile mutation, which is associated with fluoroquinolone resistance. flaA PCR restriction fragment length polymorphism (RFLP) typing to differentiate the isolates below the species level revealed 12 different clusters out of 73 strains. The human isolates belonged to eight different RFLP clusters, while five clusters contained dog and human isolates.
Ampicillin ; Animals ; Campylobacter coli ; Campylobacter* ; Ciprofloxacin ; DNA Gyrase ; Dogs* ; Drug Resistance, Microbial ; Epidemiological Monitoring* ; Erythromycin ; Humans ; Korea ; Nalidixic Acid ; Phenotype ; Point Mutation ; Polymerase Chain Reaction ; Polymorphism, Restriction Fragment Length* ; Tetracycline

BACKGROUND: Extended-spectrum cephalosporins and fluoroquinolones are important antimicrobials for treating invasive salmonellosis, and emerging resistance to these antimicrobials is of paramount concern. METHODS: A total of 30 Salmonella spp. clinical isolates recovered in Gyeongsangbuk-do from 2012 to 2013 were characterized using antibiotic resistance profiles and pulsed-field gel electrophoresis (PFGE). RESULTS: A high prevalence of multidrug-resistant isolates, mainly showing an ampicillin, nalidixic acid, chloramphenicol resistance pattern, was observed. Four extended-spectrum beta-lactamase (ESBL)-producing isolates (3 CTX-M-15 isolates and 1 CTX-M-27 isolate) were found. The bla(CTX-M-27) gene was carried by an IncF conjugative plasmid in the S. Infantis isolate. The bla(CTX-M-15) gene were carried by an IncF (2 isolates) or IncHI2 (1 isolate) conjugative plasmid in S. Enteritidis. In addition, a single mutation of GyrA, Ser83Thr (1 isolates), Asp87Tyr (9 isolates), Asp87Gly (4 isolates), and Asp87Leu (3 isolates), was detected in nalidixic acid-resistant Salmonella spp. isolates. XbaI PFGE analysis of all isolates revealed more than 19 different pulsotypes. The most common S. Enteritidis PFGE pattern (SEGX01.003) was associated with a larger number of cases of invasive salmonellosis than all other patterns. CONCLUSION: The information from our study can assist in source attribution, outbreak investigations, and tailoring of interventions to maximize disease prevention.
Ampicillin ; beta-Lactamases ; Cephalosporins ; Chloramphenicol Resistance ; Drug Resistance ; Drug Resistance, Microbial ; Electrophoresis, Gel, Pulsed-Field ; Fluoroquinolones ; Gyeongsangbuk-do ; Nalidixic Acid ; Plasmids ; Prevalence ; Salmonella Infections ; Salmonella*