BACKGROUND: Escherichia coli and Klebsiella pneumoniae clinical isolates producing CTX-M extendedspectrum β-lactamases (ESBLs) were assessed for antimicrobial resistance phenotypes varied by group of enzymes. METHODS: A total of 1,338 blood isolates, including 959 E. coli and 379 K. pneumoniae, were studied. All the strains were collected between January and July 2017 from eight general hospitals in South Korea. The species were identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry. Antimicrobial susceptibilities were determined by disk diffusion methods and ESBL phenotypes by double-disk synergy tests using disks containing cefotaxime, ceftazidime, cefepime, aztreonam, and clavulanic acid (CA). The genes for β-lactamases were identified by PCR and sequencing. RESULTS: Of total microbes, 31.6% (303/959) E. coli and 24.0% (91/379) K. pneumoniae were resistant to cefotaxime and 28.1% (269/959) E. coli and 20.1% (76/379) K. pneumoniae were CTX-M-type ESBL producers. Among the detected CTX-M ESBLs, 58.0% (156/269) in E. coli and 86.8% (66/76) in K. pneumoniae belonged to group 1, 46.8% (126/269) in E. coli and 14.5% (11/76) in K. pneumoniae were group 9. Ten E. coli and one K. pneumoniae isolates co-produced both groups of CTX-M ESBL. The group 1 CTX-M producers had a higher level of resistance to cefotaxime, ceftazidime, cefepime, and aztreonam and exhibited stronger synergistic activities when combined with CA compared to group 9. CONCLUSION: ESBL phenotypes differ by CTX-M ESBL group and phenotype testing with drugs including 4th generation cephalosporins and monobactams is critical for screening CTX-M-producers with better sensitivity.
Aztreonam ; Cefotaxime ; Ceftazidime ; Cephalosporins ; Clavulanic Acid ; Diffusion ; Escherichia coli ; Hospitals, General ; Klebsiella pneumoniae ; Korea ; Mass Screening ; Mass Spectrometry ; Monobactams ; Phenotype ; Pneumonia ; Polymerase Chain Reaction

A urinary tract infection (UTI) is a collective term for infections that involve any part of the urinary tract. It is one of the most common infections in local primary care. The incidence of UTIs in adult males aged under 50 years is low, with adult women being 30 times more likely than men to develop a UTI. Appropriate classification of UTI into simple or complicated forms guides its management and the ORENUC classification can be used. Diagnosis of a UTI is based on a focused history, with appropriate investigations depending on individual risk factors. Simple uncomplicated cystitis responds very well to oral antibiotics, but complicated UTIs may require early imaging, and referral to the emergency department or hospitalisation to prevent urosepsis may be warranted. Escherichia coli remains the predominant uropathogen in acute community-acquired uncomplicated UTIs and amoxicillin-clavulanate is useful as a first-line antibiotic. Family physicians are capable of managing most UTIs if guided by appropriate history, investigations and appropriate antibiotics to achieve good outcomes and minimise antibiotic resistance.
Adult ; Aged ; Amoxicillin ; administration & dosage ; Amoxicillin-Potassium Clavulanate Combination ; Anti-Bacterial Agents ; Clavulanic Acid ; administration & dosage ; Cystitis ; drug therapy ; Drug Resistance, Microbial ; Escherichia coli ; Escherichia coli Infections ; drug therapy ; epidemiology ; Female ; Humans ; Incidence ; Male ; Middle Aged ; Primary Health Care ; Risk Factors ; Urinary Tract Infections ; drug therapy ; epidemiology

OBJECTIVES: The increased prevalence of antibiotic resistance is an outcome of evolution. Most patients presenting with odontogenic space infections also have associated systemic co-morbidities such as diabetes mellitus resulting in impaired host defense. The present study aims to compare the odontogenic spaces involved, antibiotic susceptibility of microorganisms, length of hospital stay, and the infl uence of systemic comorbidities on treatment outcome in diabetic patients. MATERIALS AND METHODS: A 2-year prospective study from January 2012 to January 2014 was conducted on patients with odontogenic maxillofacial space infections. The patients were divided into two groups based on their glycemic levels. The data were compiled and statistically analyzed. RESULTS: A total of 188 patients were included in the study that underwent surgical incision and drainage, removal of infection source, specimen collection for culture-sensitivity, and evaluation of diabetic status. Sixty-one out of 188 patients were found to be diabetic. The submandibular space was the most commonly involved space, and the most prevalent microorganism was Klebsiella pneumoniae in diabetics and group D Streptococcus in the nondiabetic group. CONCLUSION: The submandibular space was found to be the most commonly involved space, irrespective of glycemic control. Empiric antibiotic therapy with amoxicillin plus clavulanic acid combined with metronidazole with optimal glycemic control and surgical drainage of infection led to resolution of infection in diabetic as well as nondiabetic patients. The average length of hospital stay was found to be relatively longer in diabetic individuals.
Amoxicillin ; Clavulanic Acid ; Comorbidity ; Diabetes Mellitus ; Drainage ; Drug Resistance, Microbial ; Humans ; Klebsiella pneumoniae ; Length of Stay ; Metronidazole ; Prevalence ; Prospective Studies ; Specimen Handling ; Streptococcus ; Treatment Outcome

BACKGROUNDA prior study showed significant antibiotic resistance to quinolone in our population. In this study we aimed to evaluate and compare the efficacy of a single versus a combined prophylactic antibiotic regimen before transrectal ultrasound-guided prostate biopsy (TRUGPB).

METHODSA prospective randomized study was conducted at a university hospital. Patients undergoing TRUGPB were randomized into an amoxicillin-clavulanate alone (1 mg; one dose before and two doses after biopsy) or an amoxicillin-clavulanate + ciprofloxacin group (250 mg; one dose before and two doses after biopsy). Patients were surveyed for infection symptoms by phone on days 3 and 30 after TRUGPB. We defined an infective complication as the occurrence of symptoms including fever, chills or rigor within 30 days after prostate biopsy, requiring medical treatment or hospitalization, aided by a territory-wide electronic medical record system.

RESULTSBetween November 2007 and July 2009, 367 patients were randomized to either amoxicillin-clavulanate alone or amoxicillin-clavulanate + ciprofloxacin group. The infection rates after TRUGPB were 3.91% in the former group (7 out of 179 patients) versus 0.53% (1 out of 188 patients) in the latter. Sixty-three percent (5/8) of patients with infective complications needed hospitalization. There was no intensive care unit admission or mortality during the study period.

CONCLUSIONSCombining prophylactic antibiotics with amoxicillin-clavulanate + ciprofloxacin significantly reduced the incidence of infective complications after TRUGPB. We recommended a combination regimen, especially in centre with high incidence of post-TRUGPB infection.

Amoxicillin ; therapeutic use ; Anti-Bacterial Agents ; therapeutic use ; Antibiotic Prophylaxis ; methods ; Biopsy, Needle ; adverse effects ; methods ; Ciprofloxacin ; therapeutic use ; Clavulanic Acid ; therapeutic use ; Humans ; Male ; Prostate ; diagnostic imaging ; pathology ; surgery ; Rectum ; Ultrasonography

OBJECTIVES: Currently established first line therapy of acute (presumed bacterial) rhinosinusitis (ARS) consists of 10 to 14 days of oral amoxicillin or cephalosporins. This study compared the clinical efficacy and tolerance of cefcapene pivoxil (CP) and amoxicillin-clavulanate (AMC) in patients with ARS. METHODS: A randomized, open labeled, double-blinded trial of ARS patients over 15 years of age was performed. Patients diagnosed with ARS received paranasal sinus X-rays and nasal endoscopies and 2 weeks of either CP (150 mg, 3 times/ day) or AMC (625 mg, amoxicillin 500 mg, 3 times/day). All patients revisited the clinic on days 7, 14, and 28 for evaluation of changes in symptoms, endoscopy, and monitoring of any adverse reactions. Demographics, clinical characteristics and drug efficacy were also compared between the two groups. RESULTS: Among the 60 initially enrolled patients (CP 30, AMC 30), 5 patients in the CP group and 6 in the AMC group were excluded due to poor compliance. There were no significant differences in demographic data including age, sex, initial signs and symptoms, endoscopic and X-ray findings between the two groups. Rates of improvement after 2 weeks were 96% and 95.8% in the CP and AMC group, respectively. Sinus symptoms were changed significantly after 2 and 4 weeks, however, there was no difference between groups (P=0.41). The most common adverse reaction was gastrointestinal complication, diarrhea occurred in 1 patient in the CP group and 6 in the AMC group (P=0.04). CONCLUSION: CP and AMC were both effective in treating ARS. The difference of treatment outcome was not found between the two groups, however, gastrointestinal complications were less prevalent in the CP group.
Amoxicillin ; Amoxicillin-Potassium Clavulanate Combination ; Bacterial Infections ; Cephalosporins ; Clavulanic Acid ; Compliance ; Demography ; Diarrhea ; Double-Blind Method ; Endoscopy ; Humans ; Sinusitis ; Treatment Outcome

OBJECTIVETo establish a chromatography-based method for simultaneous analysis of the concentrations of amoxicillin and clavulanate potassium in human blood.

METHODSWith paracetamol as the internal control, human plasma samples, after treatment with methanol for protein sedimentation and centrifugation, were loaded for analysis with high-performance liquid chromatography (HPLC). HPLC analysis was carried out using a C18 column (5 µm, 4.6 mm×150 mm) with the mobile phase of acetonitrile-PBS (0.05 mol/L) of 10:90 (pH 2.3), UV detection wavelength of 220 nm, flow rate of 1.0 ml/min, and column temperature of 25 degrees celsius;.

RESULTSThe retention time of acetaminophen for potassium clavulanate, amoxicillin sodium and the internal control was 5.3, 7.2, and 8.5 min, respectively, and no interference by the endogenous impurities in the plasma samples was found. Amoxicillin sodium showed a good linearity within the concentration range of 0.52-4.16 µg/ml (r(2)=0.9996), and potassium clavulanate had a good linearity within the range of 0.266-2.14 µg/ml (r(2)=0.9998). The minimum detectable concentrations of amoxicillin sodium and potassium clavulanate were 0.065 µg/ml and 0.066 µg/ml, respectively. The relative recoveries of amoxicillin sodium were 95.9%-96.5% (n=5), and those of clavulanate potassium were 92.5%-98.8% (n=5); the intra- and inter-day RSD of amoxicillin sodium was 1.84%-6.4% and 2.1%-7.8%, as compared to that of potassium clavulanate of 3.57%-8.6% and 1.8%-9.1%, respectively.

CONCLUSIONThis method is simple, accurate, sensitive, specific and reproducible for analyzing the concentrations of amoxicillin and clavulanate potassium simultaneously in human plasma.

Amoxicillin ; blood ; Chromatography, High Pressure Liquid ; methods ; Clavulanic Acid ; blood ; Drug Stability ; Humans

BACKGROUND: Accurate detection of extended spectrum beta-lactamase (ESBL) is important because ESBLproducing organisms may appear susceptible to oxyimino- beta-lactams in standard susceptibility tests, but are considered to be clinically resistant to these drugs. And continued monitoring of isolation trend of ESBL-producing organisms is essential for the guideline settlement of antibiotic usage and infection control program. METHODS: Disk diffusion test using the Clinical and Laboratory Standards Institute's ESBL phenotypic confirmatory test were performed on 5,511 clinical isolates of Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca, and Proteus mirabilis during the recent six years (April 2001-March 2007). The ESBL producer was defined as an organism showing an increase in the zone diameter of > or =5 mm for either cefotaxime or ceftazidime with clavulanic acid versus that without clavulanic acid (CTC confirmatory test, CZC confirmatory test, respectively). RESULTS: The ESBL-positive rates were 34.8% in K. pneumoniae, 9.3% in K. oxytoca, 8.4% in E. coli, and 6.5% in P. mirabilis. Among the ESBL-positive organisms, the detection rates of ESBL CTC and CZC confirmatory tests were as follows: 91.3% vs 68.7% in K. pneumoniae, 96.3% vs 44.4% in K. oxytoca, 94.8% vs 45.4% in E. coli, and 100% vs 20% in P. mirabilis. ESBL-producing K. pneumoniae had shown a continuously increasing trend from 24.3% in 2001 to 46.4% in 2006. CONCLUSION: Both of the ESBL confirmatory tests should be simultaneously tested for the accurate detection of ESBL-producing K. pneumoniae, K. oxytoca, E. coli, and P. mirabilis. In addition, an active infection control approach is needed for ESBL-producing K. pneumoniae.
beta-Lactamases* ; beta-Lactams ; Cefotaxime ; Ceftazidime ; Clavulanic Acid ; Diffusion ; Escherichia coli* ; Escherichia* ; Infection Control ; Klebsiella oxytoca ; Klebsiella pneumoniae ; Klebsiella* ; Mirabilis ; Pneumonia ; Proteus mirabilis* ; Proteus*

Chronic obstructive pulmonary disease (COPD) is the fourth leading cause of death in the United States, and is projected to rank fifth in 2020 as a worldwide burden of disease. It accounts for approximately 500,000 hospitalizations for exacerbations each year. According to a nationwide survey in Korea, the prevalence of COPD is 7.7%. New definitions of acute COPD exacerbation have been suggested, but the one used by Anthonisen is still widely accepted. It requires the presence of one or more of the following findings: increase in sputum purulence, increase in sputum volume, and worsening of dyspnea. The etiology of the exacerbations is mainly infectious. Patients experiencing COPD exacerbations with clinical signs of airway infection may benefit from antibiotic treatment. Antibiotic use has been shown to be beneficial, especially for patients with severe exacerbation. When initiating empirical antibiotic treatment physicians should always take account of any guidance issued by their local microbiologists. Antibiotic choices for patients with uncomplicated COPD include an advanced macrolide (azithromycin or clarithromycin), a ketolide (telithromycin), a cephalosporin (cefuroxime, cefpodoxime, or cefdinir) or doxycycline. In patients with complicated COPD, antibiotic choices include a new fluoroquinolone (moxifloxacin, gemifloxacin, gatfloxacin, or levofloxacin) or amoxicillin clavulanate. If Pseudomonas and other Enterobactereaces species are suspected, a combination therapy should be considered. When the initial empiric antimicrobial therapy fails, it would be appropriate to reevaluate the patient to confirm the diagnosis, to consider sputum studies to ascertain for resistant or difficult-to-treat pathogens, and to treat with an alternative agent with a better in vitro microbiologic efficacy.
Amoxicillin ; Anti-Bacterial Agents* ; Cause of Death ; Clavulanic Acid ; Diagnosis ; Doxycycline ; Dyspnea ; Hospitalization ; Humans ; Korea ; Prevalence ; Pseudomonas ; Pulmonary Disease, Chronic Obstructive* ; Sputum ; United States

PURPOSE: S. pneumoniae is one of major pathogens of community-acquired respiratory infections. The rate of antibiotic resistance to this organism has increased, and resistance to multiple antimicrobial agents in a single strain of S. pneumoniae may compromise the efficacy of empiric antimicrobial treatment commonly used for respiratory infections. We did this study to find out the penicillin resistant distributions and oral antibiotics susceptibility patterns against S. pneumoniae, isolated from pediatric patients with community-acquired respiratory infections in Korea. METHODS: One hundred fifty six pneumococcal isolates obtained from pediatric patients with community-acquired respiratory infections such as acute otitis media(AOM), sinusitis and pneumonia between May 2000 to June 2003. And MICs of penicillin and oral antibiotics(amoxicillin, amoxicillin- clavulanate, cefaclor) were performed by broth microdilution methods according to the NCCLS(2003a). RESULTS: Seventy eight percent of the isolates were resistant to penicillin. The isolates, collected from AOM patients showed the highest penicillin resistance(92.7%). The resistant rates of amoxicillin (16.7%) and amoxicillin-clavulanate(9.6%), based on susceptibility breakpoints established by the NCCLS, were markedly lower than these of penicillin. But, the resistant rate of cefaclor was very high, above 95%. CONCLUSION: We concluded that pneumococci isolated from study cases may be one of the world's highest penicillin resistant rates. But, amoxicillin and amoxicillin-clavulanate can be used as a first- line antibiotics. Finally, we hope that a continuous surveillance study to monitor resistant patterns of pneumococcal respiratory infections will be needed for the standard guidelines of empiric antibiotic treatment.
Amoxicillin ; Anti-Bacterial Agents* ; Anti-Infective Agents ; Cefaclor ; Clavulanic Acid ; Community-Acquired Infections ; Drug Resistance, Microbial ; Hope ; Humans ; Korea* ; Otitis ; Penicillin Resistance ; Penicillins* ; Pneumonia ; Respiratory Tract Infections* ; Sinusitis ; Streptococcus pneumoniae* ; Streptococcus*

A simple, rapid, sensitive, precise and accurate high-performance liquid chromatographic (HPLC) method with ultraviolet detection at wavelength of 205nm has been validated for the simultaneous determination of amoxicillin and clavulanic acid in human serum. Serum samples were deproteinized with methanol. The separation of 2 obtained compounds was achieved using a reversed phase C8 column and a mobile phase, consisting of acetonitrile-phosphate solution. The calibration curves were linear over the concentration range of 0.625 – 10 g.ml-1 for amoxicillin and 0.3125 – 5 g.ml-1 for clavulanic acid. The quantitative limits are 0.625 and 0.3125 g.ml-1 for amoxicillin and clavulanic acid. Analytical recoveries from human serum ranged from 93 to 96% for both components. This method was fully validated. It allows the simultaneous assay of amoxicillin and clavulanic acid in biomedical applications. This method has been successfully applied to a pilot pharmacokinetic study in 3 healthy volunteers after a single oral administration of amoxicillin and clavulanic acid combination
Amoxicillin ; Clavulanic Acid ; Serum ; Chromatography, High Pressure Liquid