One hundred and thirty trimethoprim-resistant R plasmids derived from of Escherichia coli isolated from clinical specimens and feces of healthy collegians were examined for incompatibility, EcoRI endonuclease restriction fragment pattern, and Southern hybridization with DHFR I, II, III, V, and VII probe. 1. Most trimethoprim-resistant R plasmids were resistant to ampicillin, tetracycline, chloramphenicol, gentamicin, and kanamycin, and showed multiple drug resistance and various antimicrobial resistance patterns. 2. Trimethoprim-resistant R plasmids ranged from 90 to 50 kilobase and 42.3% of R plasmids tested were classified to incompatibilty group Inc FI, Inc FII or Inc FIV, 3. Among 48 random selected R plasmids from various origin, 14 R plasmids (including 9 of 14 Inc FII plasmids and 3 of 14 Inc FI plasmids) hybridized with DHFR VII oligonucleotide probe but others did not respond to any of DHFR probes used. 4. Most R plasmids showed various EcoRI endonuclease fragments and different reaction sites by Southern hybridization. Six plasmids showed identical or nearly identical molecular weight, EcoRI endonuclease fragment patterns and different sites of Southern hybridization. But 2 Inc FII plasmids derived from urine and feces showed identical pattern. These findings, if confirmed by further studies, suggest that normal flora E. coli can act as reservoir of resistant genes and, consequently, as a factor in the dissemination of these genes among enteric pathogens and need to be examined further.
Ampicillin ; Chloramphenicol ; Deoxyribonuclease EcoRI ; Drug Resistance, Multiple ; Escherichia coli* ; Escherichia* ; Feces ; Gentamicins ; Immunodeficiency Virus, Feline ; Kanamycin ; Molecular Biology* ; Molecular Weight ; Plasmids ; R Factors ; Tetracycline ; Trimethoprim Resistance* ; Trimethoprim*

One hundred and twenty-two strains of E. coli isolated from urinary tract infection were examined for antibiogram, transferability of trimethoprim (Tp) resistance, incompatibility with F group plasmid and southem hybridization with DHFR I, II, and III probe of Tp-resistant R plasmids. 1. Among 172 Gram negative bacilli isolated from urinary tract infection, 122 (70.9%) were E. coli and 75 strains of them were resistant to trimethoprim (Tp). Most of Tp-resistant isolates were also resistant to penicillins (ampicillin, carbenicillin, and ticarcillin), aminoglycosides (kanamycin and gentamicin), and sulfisoxazole but almost all strains were susceptible to cephalosporins. 2. Most of Tp-resistant strains and E. coli transconjugant derived from them showed multiple drug resistance and various antimicrobial resistance patterns. 3. Thirty-three Tp-resistant strains (45.2%) transferred 35 Tp-resistant plasmids to E. coli recipients but among them 6 transconjugants did not show retransfer of resistance and plasmid DNA were not detected in 2 transconjugants after resistance transfer. 4. Tp-resistant R plasmids ranged from 157 to 67 kb and 8 R plasmids were classified to incompatibilty group IncFI or IncFII ranging from 120 to 83 kb. Three and two R plasmids belonged to IncFII showed similar molecular weight, resistance pattern, and reaction site by southern hybridization with DHFR I probe. Twenty-five plasmids specifically responded on various EcoRI endonuclease fragments to DHFR I probe but not to DHFR II or DHFR III probe. These findings suggest that most of Tp- resistant R plasmids from urine isolates of E. coli were derived from various sources but some plasmids including IncFII R plasmids were probably originated from same or similar sources.
Aminoglycosides ; Carbenicillin ; Cephalosporins ; Deoxyribonuclease EcoRI ; DNA ; Drug Resistance, Multiple ; Escherichia coli* ; Escherichia* ; Microbial Sensitivity Tests ; Molecular Weight ; Penicillins ; Plasmids ; R Factors ; Sulfisoxazole ; Trimethoprim Resistance* ; Trimethoprim* ; Urinary Tract Infections

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.

The emergence and spread of antimicrobial resistance among the pathogenic and commensal Enterobacteriaceae are of great concern worldwide. We characterized the antimicrobial resistance and integrons found in commensal Escherichia coli from healthy humans in the community. Class 1 integrase (intl1) and class 2 integrase (intl2) genes were identified in 22 (13.3%) and 2 (1.2%) of 165 E. coli isolates, respectively. dfrA17-aadA5 and dfrA1-aadA2 were the most common class 1 integrons. The prevalence of each type of class 1 integron among commensal E. coli isolates during 2001~2003 was similar to that of clinical E. coli isolates from hospital-acquired infections during 1994~1999. The resistant rates of commensal E. coli isolates carrying intl1 to ampicillin, streptomycin, gentamicin, sulfamethoxazole, trimethoprim, chloramphenicol, and tetracycline were significantly higher than those of intl1-negative E. coli isolates (p<0.05). Integrons were directly associated with multidrug resistance in commensal E. coli isolates. It is hypothesized that multidrug-resistant Enterobacteriaceae from hospital-acquired infections are a potential reservoir for integrons associated with resistance genes found in commensal E. coli isolates in the community
Ampicillin ; Chloramphenicol ; Drug Resistance, Multiple ; Enterobacteriaceae ; Escherichia coli* ; Escherichia* ; Gentamicins ; Humans* ; Integrases ; Integrons* ; Prevalence ; Streptomycin ; Sulfamethoxazole ; Tetracycline ; Trimethoprim

BACKGROUND: The students who had traveled in Jeju island developed symptoms of diarrhea at a girls' high school in Busan, June 2000. The goals of this study are to investigate the pattern of shigellosis and to compare drug resistance to S. sonnei with recent studies by reference reports. METHODS: Through epidemiological investigation and stool test of new patients, 993 students were registered from Jun.12 to 17, 2000 in a girls' high school, Busan. 2nd grade students(N=355) who had traveled in Jeju island described a questionnaire of the source of infection. Clinical and bacteriological studies were carried out on 6 cases of patients with S. sonnei. RESULTS: Among total 993 students, 79 patients were considered to have diarrhea. But 54 patients of 2nd grade students developed symptoms of diarrhea(14.7%) and the analysis of associative symptoms showed that it contained abdominal pain(72.2%), headache(61.6%), tenesmus(57.4%). 43 students of 2nd grade students who had traveled in Jeju ate chinese foods. Of them, 40 students showed diarrhea(93.0%) confirmed shigellosis(6 students), probable shigellosis(34 students). S. sonnei was isolated from 6 patients(14.0%). The attack rate of diarrhea was 20.7 times more in the group eating chinese foods than in the group not eating chinese foods(p<0.001). After the 2nd grade students ate chinese foods in Jeju, diarrhea attack day distribution was first day(23.2%), second day(39.7%), and third day(16.3%). The result of drug resistance test to S. sonnei(ampicillin, amoxicillin/clavulanic acid, tetracycline, sulfamethoxazole trimethoprim, and streptomycin) was 100%. CONCLUSION: The 2nd grade patients with shigellosis ate chinese foods in a restaurant, Jeju. The pattern of antibiotic resistance to S. sonnei was different from that of several previous cases of shigellosis in Busan.
Asian Continental Ancestry Group ; Busan* ; Diarrhea ; Drug Resistance ; Drug Resistance, Microbial ; Dysentery, Bacillary ; Eating ; Epidemiologic Studies* ; Humans ; Restaurants ; Shigella sonnei* ; Shigella* ; Sulfamethoxazole ; Tetracycline ; Trimethoprim ; Surveys and Questionnaires

The frequency of antibiotic resistance among Salmonella enterica serovar Typhimurium has increased due to the transfer of multiple resistance factors. We detected the 13 antibiotic resistance genes by multiplex-PCR and compared with the results of phage typing and antibiotic disk diffusion for 49 S. typhimurium isolated from food-poisoning outbreaks in Seoul from 1999 to 2002. Resistance genes for tetracycline, streptomycin, ampicillin, sulfonamide, amino-glycoside-modifying enzyme, chloramphenicol, kanamycin, and trimethoprim were detected in 67.3%, 57.1%, 26.5%, 8.1%, 8.1%, 5%, 2.0%, and 0% of isolates, respectively. Overall 28 isolates (57.1%) possessed two or more antibiotic resistance genes. Class 1 integron carrying multidrug resistace genes, ant(3")-IaB, blaPSE, qacE delta1/sul, and tet G were amplified especially in only DT104 isolates. Among the related resistance genes for same antibiotics, strA and strB for streptomycin resistance were simultaneously detected but tetA and tetB for tetracycline were sporadically detected. DT 104 isolates contained only aadA2 and tetG.
Ampicillin ; Anti-Bacterial Agents ; Bacteriophage Typing ; Chloramphenicol ; Diffusion ; Disease Outbreaks ; Drug Resistance, Microbial ; Humans ; Integrons ; Kanamycin ; R Factors ; Salmonella enterica* ; Salmonella* ; Seoul* ; Streptomycin ; Tetracycline ; Trimethoprim

Conjugative R plasmids derived from 74 clinical isolates of Serratia marcescens were epidemiologically analyzed for antimicrobial resistance, EcoRI restriction endonuclease analysis and Southern hybridization with DHFR, TEM and SHV probe. 1. Resistance frequency of isolates against various B-lactam antibiotics was changed by year. 2. Twenty (27%) resistant strains transferred 32 R plasmids to E. coli or Klebsiella by mixed culture. Most strains isolated from 1994 to 1996 transferred only trimethoprim resistance but most strains isolated from 1997 did resistances against gentamicin (Gm) and B-lactams including ampicillin (Ap), carbenicillin (Cb), cefazolin (Cz), cefaloridine (Cl), cefamandole (Cn). 3. Ten plasmids of GmApCbCzC1Cn or GmApCbCzC1 pattern and 3 plasmids of TcSuGmTbApCbCzC1 pattern respectively showed identical EcoRI restriction endonuclease digestion patterns and hybridized fragment patterns with TEM-1 probe by Southern hybridization. These results indicate that the epidemic plasmids carrying blamM gene were present in this hospital in 1997 and molecular genetic analysis of R plasmids can be used to discriminate S. marcescens isolates for epidemiologic studies.
Ampicillin ; Anti-Bacterial Agents ; Carbenicillin ; Cefamandole ; Cefazolin ; Cephaloridine ; Digestion ; DNA Restriction Enzymes ; Epidemiologic Studies ; Epidemiology* ; Gentamicins ; Klebsiella ; Molecular Biology ; Plasmids ; R Factors ; Serratia marcescens* ; Serratia* ; Trimethoprim Resistance

Acute uncomplicated urinary tract infections (UTI), episodes of cystitis or pyelonephritis that occur in healthy non-pregnant women with no functional or anatomic abnormalities of the urinary tract, are among the most commonly encountered bacterial infections. Unfortunately, there has been a recent trend of increasing resistance to antibiotics among uropathogens in many countries including Korea. The resistance rates of Escherichia coli from acute uncomplicated UTI during 2009 to ciprofloxacin (CIP), trimethoprim-sulfamethoxazole (SXT) and cefotaxime were 84.1%, 67.2% and 95.4%, respectively. Resistance both to SXT and CIP was detected in 10.6% of the E. coli isolates. Therefore, it is difficult to recommend the antibiotics which would not worsen the resistance problem and would be effective for community-acquired uncomplicated UTI as well. Considering the high resistance of uropathogens in Korea, several academic societies made the guideline for UTI, which will be briefly reviewed in this manuscript.
Anti-Bacterial Agents ; Bacterial Infections ; Cefotaxime ; Ciprofloxacin ; Cystitis ; Drug Resistance, Microbial ; Escherichia coli ; Female ; Humans ; Korea ; Pyelonephritis ; Trimethoprim, Sulfamethoxazole Drug Combination ; Urinary Tract ; Urinary Tract Infections

Acute uncomplicated urinary tract infections (UTI), episodes of cystitis or pyelonephritis that occur in healthy non-pregnant women with no functional or anatomic abnormalities of the urinary tract, are among the most commonly encountered bacterial infections. Unfortunately, there has been a recent trend of increasing resistance to antibiotics among uropathogens in many countries including Korea. The resistance rates of Escherichia coli from acute uncomplicated UTI during 2009 to ciprofloxacin (CIP), trimethoprim-sulfamethoxazole (SXT) and cefotaxime were 84.1%, 67.2% and 95.4%, respectively. Resistance both to SXT and CIP was detected in 10.6% of the E. coli isolates. Therefore, it is difficult to recommend the antibiotics which would not worsen the resistance problem and would be effective for community-acquired uncomplicated UTI as well. Considering the high resistance of uropathogens in Korea, several academic societies made the guideline for UTI, which will be briefly reviewed in this manuscript.
Anti-Bacterial Agents ; Bacterial Infections ; Cefotaxime ; Ciprofloxacin ; Cystitis ; Drug Resistance, Microbial ; Escherichia coli ; Female ; Humans ; Korea ; Pyelonephritis ; Trimethoprim, Sulfamethoxazole Drug Combination ; Urinary Tract ; Urinary Tract Infections

BACKGROUND: The aim of this study was to evaluate the Vitek system and the disk diffusion method for susceptibility testing of Enterobacteriaceaeagainst piperacillin-tazobactam (TZP) and methicillin-resistant Staphylococcus aureus (MRSA) against trimethoprim-sulfamethoxazole (SXT)using the broth microdilution method as the reference. METHODS: Using the Vitek system and the disk diffusion method, we tested 96 isolates of Enterobacteriaceae (48 Escherichia coli, 26 Klebsiella pneumoniae, 8 Serratia marcescens, 6 Enterobacter cloacae, 2 E. aerogenes, 2 K. oxytoca, 2 Citrobacter freundii, 2 Pantoea agglomerans) and 61 isolates of MRSA for susceptibity against TZP and SXT, respectively; the broth microdilution of National Committee for Clinical Laboratory Standards was used as the reference method. RESULTS: In the susceptibility testing of Enterobacteriaceae against TZP, Vitek system yielded 10 (10%) minor errors, and the disk diffusion method one (1%) very major and 13 (14%) minor errors. For the MRSA against SXT, the rate of categorical agreement between the reference method and the Vitek or the disk diffusion method was both 100%. The rates of agreement between the reference method and the Vitek system in term of MICs (within +/-1 dilution) were 93% and 98% in the susceptibility testing of Enterobacteriaceae against TZP and MRSA against SXT, respectively. CONCLUSION: Both Vitek system and disk diffusion method showed an acceptable level of accuracy for the susceptibility test of Enterobacteriaceaeagainst TZP and MRSA against SXT.
Citrobacter freundii ; Diffusion* ; Enterobacter cloacae ; Enterobacteriaceae* ; Escherichia coli ; Klebsiella pneumoniae ; Methicillin Resistance* ; Methicillin-Resistant Staphylococcus aureus* ; Pantoea ; Serratia marcescens ; Trimethoprim, Sulfamethoxazole Drug Combination*