Background: Streptococcus pneumonia (S.pneumoniae) is the main cause of acquired pneumonia in the community along with otitis media, sinusitis, septicemia and meningitis. Objectives: The study determined antimicrobial resistance and serotype distribution of Streptococcus pneumonia isolates from hospitalized children at Hai Phong Children's Hospital, Vietnam. Subjects and method: From June 2006 to September 2007, 80 pneumococccal isolates were tested for susceptibility to the 13 antibiotics and 84 pneumococcal isolates were serotyped. Results:Seventy-five percent of strains showed multi-drug resistance. Ninety percent of strains showed resistance to penicillin (48% intermediate and 42% fully resistant). In addition, 100% of isolates were resistant to cotrimoxazole, 74% of isolates were resistant to cephalexin; 71 % of isolates were resistant to erythroomycin and 58% were resistant to cefuroxxime. Almost all the isolates were susceptible to amoxicillin, cefotaxime, ceftriaxone, ceefepime, ofloxacin and 100% of isolates were susceptible to vancomycin. Among the 84 serotypes, 82% were included in the 23 valent pneumococcal polysaccharide vaccine including: 19F (30%), 23F (21 %), 14 (13%) and 6B (13%). Six other serotypes (13, 15C, 18, 11A, 15B and 6A) accounted for 12% of strains and 9 (11%) strains were untypeable. Conclusion: Pneumococcal antibiotics is spreading most rapidly among children in Vietnam, especially strains typs 19F and 23 F. Concerted efforts are necessary to prevent it spreading.\r\n", u'\r\n', u'
Antimicrobial resistance ; streptococcus pneumonia

Antibiotic resistance of urinary tract pathogens has increased worldwide. The purpose of this study is to provide information regarding local resistance pattern of urinary pathogens to the commonly used antibiotics. One hundred and seventeen cases of community-acquired urinary tract infections were studied. The most common group of patients was the uncomplicated acute cystitis in women. E. coli was the most common isolate. Overall, antimicrobial susceptibility test on the organisms isolated showed a resistance of 63.0% to ampicillin, 40.1% to sulfamethoxazole-trimethoprim (S-T), 14.3% to pipemidic acid, 8.6% to norfloxacin, 3.8% to cephalexin, 3.7% to amoxicillin-clavulanate, 1.0% to cefuroxime, and 1.0% to fosfomycin. Three out of five patients on ampicillin as well as two out of five patients on S-T were likely to be inadequately treated.
Cancer resistance to treatment ; Community ; Upper case tea ; Upper case ess ; Antimicrobial susceptibility

The recent emergence of Staphylococcus schleiferi in dogs with otitis externa or skin and soft tissue infections has become a significant zoonotic issues. In the current study, we investigated 1) the carriage rates of S. schleiferi among major staphylococci in healthy dogs and dogs with otitis externa, 2) antibiotic susceptibility profiles of S. schleiferi, particularly methicillin resistance (MR), and 3) virulence factors associated with skin and soft tissue infections such as ability to form biofilm, resistance to cationic antimicrobial peptides (CAMPs), and carriage of staphylococcal enterotoxin genes. Among the 21 S. schleiferi isolates, 5 isolates (24%) were determined to be methicillin-resistant (MRSS). Staphylococcal cassette chromosome mec (SCCmec) typing revealed the presence of SCCmec type V in 4 MRSS isolates and type VII in one MRSS. Higher levels of antibiotic resistance, especially multidrug resistance, were observed in MRSS isolates compared to the methicillin-susceptible S. schleiferi (MSSS) isolates. In addition, MRSS isolates exhibited enhanced ability to form biofilm under static condition and all the 5 MRSS isolates carried three or more enterotoxin genes. However, there were no significant differences in resistance to CAMPs between MRSS and MSSS isolates. These findings suggest that coagulase-negative S. schleiferi is becoming more prevalent in canine otitis externa cases. Our results also highlight the presence of multidrug-resistant MRSS isolates with enhanced biofilm production and carriage of multiple enterotoxins.
Animals ; Antimicrobial Cationic Peptides ; Biofilms ; Dogs ; Drug Resistance, Microbial ; Drug Resistance, Multiple ; Enterotoxins ; Methicillin Resistance ; Otitis Externa ; Otitis ; Skin ; Soft Tissue Infections ; Staphylococcus ; Virulence Factors ; Virulence

Microbial biofilm, a consortium of microbial cells protected by a self-produced polymer matrix, is considered as one main cause of current bacterial drug resistance. As a new type of antimicrobial agents, antimicrobial peptides provide a new strategy for the treatment of antibiotic resistant bacteria biofilm infections. Antimicrobial peptides have shown unique advantages in preventing microbial colonization of surfaces, killing bacteria in biofilms or disrupting the mature biofilm structure. This review systemically analyzes published data in the recent 30 years to summarize the possible anti-biofilm mechanisms of antimicrobial peptides. We hope that this review can provide reference for the treatment of infectious diseases by pathogenic microbial biofilm.
Anti-Bacterial Agents ; pharmacology ; Antimicrobial Cationic Peptides ; pharmacology ; Bacteria ; drug effects ; Biofilms ; drug effects ; Drug Resistance, Bacterial ; drug effects ; Microbial Sensitivity Tests ; Research ; trends

BACKGROUND: Multidrug-resistant Enterobacteriaceae is a worldwide problem. Although various resistance mechanisms have been recognized with increasing frequency, only a few cases of triple resistance of extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae have been reported. This study was designed to evaluate the coexistence of qnr (qnrA, qnrB, and qnrS) and 16S rRNA methylase (armA, rmtA, rmtB, and rmtC) in ESBL-producing K. pneumoniae. METHODS: We tested 44 isolates of ESBL-producing K. pneumoniae at Chungnam National University Hospital from March to September 2006. Antimicrobial susceptibilities were tested by broth microdilution method, and transconjugation test was performed using E. coli J53 with azide resistance. Search for qnr (qnrA, qnrB, and qnrS) and 16S rRNA methylase (armA, rmtA, rmtB, and rmtC) genes was conducted by PCR amplification, and the genotypes were determined by direct nucleotide sequence analysis of the amplified products. Epidemiologic study was performed by Enterobacterial repetitive intergenic consensus-PCR (ERIC-PCR). RESULTS: All ESBL-positive strains produced qnrB; however, armA was detected in 68.2%. The coproduction rate of qnrB and armA in ESBL-producing K. pneumoniae was 68.2%. Two types (A and B) were dominant in ERIC-PCR results. CONCLUSIONS: K. pneumoniae producing qnrB, armA, and ESBL are spreading widely.
Bacterial Proteins/biosynthesis/*genetics ; Disk Diffusion Antimicrobial Tests ; Drug Resistance, Bacterial/genetics ; Humans ; Klebsiella Infections/microbiology ; Klebsiella pneumoniae/drug effects/*genetics/isolation & purification ; Methyltransferases/biosynthesis/*genetics ; beta-Lactamases/biosynthesis/drug effects/*genetics

BACKGROUND: Stenotrophomonas maltophilia is a gram-negative bacillus and a nosocomial pathogen in immunocompromised patients. Trimethoprim/sulfamethoxazole (TMP/SMX) is the drug of choice for treating S. maltophilia infection; however, resistance to TMP/SMX is increasing. In this study, we investigated the relationship between the incidence of TMP/SMX resistance and the presence of sul genes and mobile elements. METHODS: A total of 120 S. maltophilia isolates were collected from 3 university hospitals between April 2007 and April 2009. Antimicrobial susceptibilities were determined using the disk diffusion method. PCR and DNA sequencing were conducted for the detection of sul1, sul2, class 1 integron, and ISCR2 element. Repetitive extragenic palindromic sequence-based PCR (REP-PCR) was carried out to evaluate the genetic relatedness. RESULTS: The TMP/SMX-resistant (R) isolates harbored a significantly higher proportion of sul1 gene and class 1 integron than TMP/SMX-susceptible (S) isolates (P<0.001). Seventeen of 28 isolates with sul1 also had a class 1 integron, but none of the isolates without sul1 had a class 1 integron. The identified gene cassettes within class 1 integrons include aacA4, aadA1, aac6'-II, and qac. None of the 120 isolates carried sul2, glmM, or ISCR2 element. REP-PCR did not show any genetic relatedness among the isolates. CONCLUSIONS: In Korea, the resistance of S. maltophilia isolates to TMP/SMX is due to sul1 within a class 1 integron rather than to sul2. The class 1 integron also harbors multiple antibiotic resistance genes in addition to sul1, and therefore it could mediate multidrug resistance in S. maltophilia.
Anti-Bacterial Agents/*pharmacology ; Bacterial Proteins/genetics ; Carrier Proteins/genetics ; DNA, Bacterial/genetics ; Disk Diffusion Antimicrobial Tests ; Drug Resistance, Multiple, Bacterial/genetics ; Humans ; Integrons/genetics ; Polymerase Chain Reaction ; Stenotrophomonas maltophilia/*drug effects/*genetics/isolation &purification ; Trimethoprim-Sulfamethoxazole Combination/*pharmacology

BACKGROUND: Cinical and Laboratory Standards Institute (CLSI) recommends the use of cefoxitin disks instead of long-used oxacillin disks for screening methicillin-resistant isolates of staphylococci. The frequency of discrepant results and accuracy of the tests were evaluated by detecting mecA gene. METHODS: A total of 3,123 Stapylococci isolates from patients in Severance Hospital were tested during September 2005 to August 2006 by the CLSI-recommended test using both cefoxitin and oxacillin disks. The mecA gene was detected by PCR and the oxacillin minimum inhibitory concentration (MIC) was determined by using agar dilution method for the isolates with discrepant tests. RESULTS: Among 1,915 S. aureus islolates tested, one isolate was resistant to oxacillin disk but susceptible to cefoxitin disk; the isolate did not have mecA gene. Another isolate susceptible to oxacillin but resistant to cefoxitin had mecA gene. Among 1,208 coagulase-negative staphylococcal isolates, 15 isolates were resistant to oxacillin disk but susceptible to cefoxitin disk; the isolates did not have mecA genes. Two isolates susceptible to oxacillin disk but resistant to cefoxitin disk had mecA genes. Among the 16 Staphylococcus isolates that did not have mecA gene, 15 isolates had the oxacillin MICs of < or =2 microgram/mL and were considered as methicillin-susceptible, while 1 isolate with the MIC of 4 microgram/mL was considered as methicillin-resistant. CONCLUSIONS: Overall, 1.9% of staphylococcal isolates showed discrepant results when the screening tests were performed by using oxacillin and cefoxitin disks. None of the isolates resistant to oxacillin disk but susceptible to cefoxitin disk had mecA gene. In conclusion, the cefoxitin disk test is more reliable than oxacillin disk test in screening methicillin-resistant staphylococcal isolates.
Anti-Bacterial Agents/*pharmacology ; Bacterial Proteins/analysis/*genetics ; Cefoxitin/*pharmacology ; *Disk Diffusion Antimicrobial Tests ; Humans ; Methicillin/pharmacology ; Methicillin Resistance ; Oxacillin/*pharmacology ; Polymerase Chain Reaction ; Staphylococcal Infections/microbiology ; Staphylococcus aureus/*drug effects/isolation & purification

BACKGROUND: Cinical and Laboratory Standards Institute (CLSI) recommends the use of cefoxitin disks instead of long-used oxacillin disks for screening methicillin-resistant isolates of staphylococci. The frequency of discrepant results and accuracy of the tests were evaluated by detecting mecA gene. METHODS: A total of 3,123 Stapylococci isolates from patients in Severance Hospital were tested during September 2005 to August 2006 by the CLSI-recommended test using both cefoxitin and oxacillin disks. The mecA gene was detected by PCR and the oxacillin minimum inhibitory concentration (MIC) was determined by using agar dilution method for the isolates with discrepant tests. RESULTS: Among 1,915 S. aureus islolates tested, one isolate was resistant to oxacillin disk but susceptible to cefoxitin disk; the isolate did not have mecA gene. Another isolate susceptible to oxacillin but resistant to cefoxitin had mecA gene. Among 1,208 coagulase-negative staphylococcal isolates, 15 isolates were resistant to oxacillin disk but susceptible to cefoxitin disk; the isolates did not have mecA genes. Two isolates susceptible to oxacillin disk but resistant to cefoxitin disk had mecA genes. Among the 16 Staphylococcus isolates that did not have mecA gene, 15 isolates had the oxacillin MICs of < or =2 microgram/mL and were considered as methicillin-susceptible, while 1 isolate with the MIC of 4 microgram/mL was considered as methicillin-resistant. CONCLUSIONS: Overall, 1.9% of staphylococcal isolates showed discrepant results when the screening tests were performed by using oxacillin and cefoxitin disks. None of the isolates resistant to oxacillin disk but susceptible to cefoxitin disk had mecA gene. In conclusion, the cefoxitin disk test is more reliable than oxacillin disk test in screening methicillin-resistant staphylococcal isolates.
Anti-Bacterial Agents/*pharmacology ; Bacterial Proteins/analysis/*genetics ; Cefoxitin/*pharmacology ; *Disk Diffusion Antimicrobial Tests ; Humans ; Methicillin/pharmacology ; Methicillin Resistance ; Oxacillin/*pharmacology ; Polymerase Chain Reaction ; Staphylococcal Infections/microbiology ; Staphylococcus aureus/*drug effects/isolation & purification

No abstract availble.
Anti-Bacterial Agents/therapeutic use ; Disk Diffusion Antimicrobial Tests ; *Drug Resistance, Bacterial ; Drug Therapy, Combination ; Helicobacter Infections/*drug therapy ; *Helicobacter pylori/drug effects/isolation & purification ; Humans ; Microbial Sensitivity Tests ; Peptic Ulcer/*drug therapy

BACKGROUND: Acinetobacter baumannii is an aerobic, gram-negative, glucose-nonfermenting bacterium, which has emerged as a serious opportunistic pathogen. In recent years, the increasing instance of carbapenem-resistant A. baumannii producing metallo-beta-lactamases (MBLs) or OXAtype beta-lactamases is causing a serious clinical problem. In this study, we investigated the prevalence of Ambler class A, B, and D beta-lactamases and their extended-spectrum derivatives in carbapenem-resistant A. baumannii isolates. METHODS: A total of 31 consecutive, non-duplicate, carbapenem-resistant A. baumannii were isolated from three university hospitals in the Chungcheong province of Korea. The modified Hodge and inhibitor-potentiated disk diffusion tests were conducted for the screening of carbapenemase and MBL production, respectively. PCR and DNA sequencing were performed for the detection of beta-lactamase genes. We also employed the enterobacterial repetitive intergenic consensus (ERIC)-PCR method for the epidemiologic study. RESULTS: Twenty-three of 31 isolates harbored bla(OXA-2) (51.6%), bla(OXA-23) (22.6%), bla(IMP-1) (48.4%),and bla(VIM-2) (3.2%). All of the OXA-2-producing strains also evidenced MBLs. The strains that harbored bla(OXA-23) were isolated only in hospital C, and only in a limited fashion. The ERIC-PCR pattern of the five OXA-23 strains indicated that the isolates were closely related in terms of clonality. The six strains producing IMP-1 isolated from hospital A were confirmed to be identical strains. CONCLUSIONS: A. baumannii strains harboring IMP-1 or OXA-type beta-lactamases are currently widely distributed throughout the Chungcheong province of Korea. The most notable finding in this study was that a bla(OXA-2)-producing A. baumannii harboring MBL, which has not been previously reported, can also lead to outbreaks.
Acinetobacter Infections/microbiology ; Acinetobacter baumannii/drug effects/*enzymology/genetics ; Anti-Bacterial Agents/*pharmacology ; Carbapenems/*pharmacology ; Disk Diffusion Antimicrobial Tests ; Drug Resistance, Multiple, Bacterial ; Humans ; Polymerase Chain Reaction ; beta-Lactamases/biosynthesis/genetics/*metabolism