Antibiotic Resistance in Haemophilus influenzae Decreased, except for β-Lactamase-Negative Amoxicillin-Resistant Isolates, in Parallel with Community Antibiotic Consumption in Spain from 1997 to 2007

ABSTRACT The susceptibility to 14 antimicrobial agents and the mechanisms of aminopenicillin resistance were studied in 197 clinical isolates of Haemophilus influenzae—109 isolated in 2007 (study group) and 88 isolated in 1997 (control group). Community antibiotic consumption trends were also examined. H. influenzae strains were consecutively isolated from the same geographic area, mostly from respiratory specimens from children and adults. Overall, amoxicillin resistance decreased by 8.4% (from 38.6 to 30.2%). β-Lactamase production decreased by 15.6% (from 33 to 17.4%, P = 0.01), but amoxicillin resistance without β-lactamase production increased by 7.1% (from 5.7 to 12.8%). All β-lactamase-positive isolates were TEM-1, but five different promoter regions were identified, with Pdel being the most prevalent in both years, and Prpt being associated with the highest amoxicillin resistance. A new promoter consisting of a double repeat of 54 bp was detected. Community consumption of most antibiotics decreased, as did the geometric means of their MICs, but amoxicillin-clavulanic acid and azithromycin consumption increased by ca. 60%. For amoxicillin-clavulanic acid, a 14.2% increase in the population with an MIC of 2 to 4 μg/ml (P = 0.02) was observed; for azithromycin, a 21.2% increase in the population with an MIC of 2 to 8 μg/ml (P = 0.0005) was observed. In both periods, the most common gBLNAR (i.e., H. influenzae isolates with mutations in the ftsI gene as previously defined) patterns were IIc and IIb. Community consumption of trimethoprim-sulfamethoxazole decreased by 54%, while resistance decreased from 50 to 34.9% (P = 0.04). Antibiotic resistance in H. influenzae decreased in Spain from 1997 to 2007, but surveillance should be maintained since new forms of resistances may be developing.

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Molecular Evolution of β-Lactam-Resistant Haemophilus influenzae: 9-Year Surveillance of Penicillin-Binding Protein 3 Mutations in Isolates from Japan

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01316-05 ◽

2006 ◽

Vol 50 (7) ◽

pp. 2487-2492 ◽

Cited By ~ 50

Author(s):

Yumiko Sanbongi ◽

Takahisa Suzuki ◽

Yumi Osaki ◽

Nami Senju ◽

Takashi Ida ◽

...

Keyword(s):

Amino Acid ◽

Molecular Evolution ◽

Haemophilus Influenzae ◽

Clavulanic Acid ◽

Antimicrobial Agents ◽

Binding Protein ◽

Amino Acid Substitutions ◽

Penicillin Binding Protein ◽

Amoxicillin Clavulanic Acid ◽

Second Period

ABSTRACT A total of 621 clinical isolates of Haemophilus influenzae collected in Japan between 1995 and 2003 were studied for their susceptibilities to several antimicrobial agents, β-lactamase production, and amino acid substitutions in penicillin-binding protein 3 (PBP 3). Over the four study periods (first period, 1995 to 1996; second period, 1997 to 1998; third period, 2000 to 2001; fourth period, 2002 to 2003), the susceptibilities to β-lactam agents decreased and the incidence of isolates with substitutions at positions 377, 385, 389, 517, and/or 526 in PBP 3 increased from 28.8% to 52.0%. Five hundred seventy-one β-lactamase-nonproducing isolates were grouped into 18 classes, based on the pattern of the five mutations in PBP 3. The Asp526Lys substitution led to 6.0-, 4.3-, 2.4-, and 5.4-fold increases in amoxicillin-clavulanic acid, cefdinir, cefditoren, and faropenem resistance, respectively. PBP 3 with multiple substitutions (Met377Ile, Ser385Thr, and/or Leu389Phe) together with Asp526Lys resulted in increased resistance compared to that for PBP 3 with the Asp526Lys substitution alone. These results indicate that mutations at these five positions increased resistance to most β-lactams. Although a significant change in the prevalence of β-lactamase-producing strains was not observed, the proportions of those possessing both PBP 3 alterations and β-lactamase production have slightly increased (from 1.4% to 5.0%). The ROB-1 β-lactamase was rare, but this is the first report of this β-lactamase in Japan.

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Antibiotic resistance of canine Staphylococcus intermedius group (SIG) - practical implications

Polish Journal of Veterinary Sciences ◽

10.2478/v10181-011-0032-9 ◽

2011 ◽

Vol 14 (2) ◽

pp. 213-218 ◽

Cited By ~ 6

Author(s):

D. Chrobak ◽

M. Kizerwetter-Świda ◽

M. Rzewuska ◽

M. Binek

Keyword(s):

Antibiotic Resistance ◽

Clavulanic Acid ◽

Antimicrobial Agents ◽

Clinical Samples ◽

Rrna Gene ◽

Phenotypic Properties ◽

Diagnostic Laboratory ◽

Staphylococcus Intermedius ◽

Amoxicillin Clavulanic Acid ◽

Practical Implications

Antibiotic resistance of canineStaphylococcus intermediusgroup (SIG) - practical implicationsA total of 221 SIG strains were isolated from clinical samples of canine origin submitted to the Diagnostic Laboratory of the Division of Bacteriology and Molecular Biology at the Warsaw University of Life Sciences in Warsaw during the period 2006-2010. The aim of the study was to investigate the frequency of prevalence of methicillin-resistant SIG strains and to determine the MIC values of cephalotin, amoxicillin/clavulanic acid, ciprofloxacin, clindamycin, gentamicin, chloramphenicol, mupirocin for a collection of randomly selected 79 strains belonging toStaphylococcus intermediusgroup (SIG), including 23mecA-positive and 56mecA-negative strains. All isolates were identified as belonging to SIG based on their phenotypic properties and PCR amplification ofS. intermedius-specific fragment of the 16S rRNA gene. ThemecAgene was detected in 26 (12%) of 221 SIG strains. All testedmecA-negative SIG strains were susceptible to amoxicillin/clavulanic acid and cephalotin. One of the 56mecA-negative SIG strains was resistant to ciprofloxacin, six (11%) to gentamicin. It was found that sixteen (29%) of 56mecA-negative SIG strains were resistant to clindamycin. Most of themecA-positive SIG strains were resistant to ciprofloxacin (96%), clindamycin (96%), and gentamicin (96%). Only one MRSIG strain was resistant to chloramphenicol. All examinedmecA-positive SIG strains were found to be susceptible to mupirocin. Our results imply that staphylococcal multidrug resistance has become more prevalent, which could lead to difficulties in effective treatment. With some resistant strains the only therapeutic possibility are antimicrobial agents important in human medicine. New regulations for veterinary medicine concerning appropriate therapy of infections caused by multidrug-resistat staphylococci are needed.

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Is perioperative antibiotic necessary in straightforward implant placement procedures?

Journal of Oral Implantology ◽

10.1563/aaid-joi-d-19-00282 ◽

2020 ◽

Author(s):

Elçin Bedeloğlu ◽

Mustafa Yalçın ◽

Cenker Zeki Koyuncuoğlu

Keyword(s):

Clavulanic Acid ◽

Dental Implant ◽

Prophylactic Antibiotic ◽

Antibiotic Use ◽

Implant Failure ◽

Control Group ◽

Implant Placement ◽

Significant Difference ◽

Amoxicillin Clavulanic Acid ◽

Experimental Group

The purpose of this non-random retrospective cohort study was to evaluate the impact of prophylactic antibiotic on early outcomes including postoperative pain, swelling, bleeding and cyanosis in patients undergoing dental implant placement before prosthetic loading. Seventy-five patients (45 males, 30 females) whose dental implant placement were completed, included to the study. Patients used prophylactic antibiotics were defined as the experimental group and those who did not, were defined as the control group. The experimental group received 2 g amoxicillin + clavulanic acid 1 h preoperatively and 1 g amoxicillin + clavulanic acid twice a day for 5 days postoperatively while the control group had received no prophylactic antibiotic therapy perioperatively. Data on pain, swelling, bleeding, cyanosis, flap dehiscence, suppuration and implant failure were analyzed on postoperative days 2, 7, and 14 and week 12. No statistically significant difference was detected between the two groups with regard to pain and swelling on postoperative days 2, 7, and 14 and week 12 ( p >0.05), while the severity of pain and swelling were greater on day 2 compared to day 7 and 14 and week 12 in both groups ( p =0.001 and p <0.05, respectively). Similarly, no significant difference was found between the two groups with regard to postoperative bleeding and cyanosis. Although flap dehiscence was more severe on day 7 in the experimental group, no significant difference was found between the two groups with regard to the percentage of flap dehiscence assessed at other time points. Within limitations of the study, it has been demonstrated that antibiotic use has no effect on implant failure rates in dental implant surgery with a limited number of implants. We conclude that perioperative antibiotic use may not be required in straightforward implant placement procedures. Further randomized control clinical studies with higher numbers of patients and implants are needed to substantiate our findings.

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Influence of TEM-1 β-Lactamase on the Pharmacodynamic Activity of Simulated Total versus Free-Drug Serum Concentrations of Cefditoren (400 Milligrams) versus Amoxicillin-Clavulanic Acid (2,000/125 Milligrams) against Haemophilus influenzae Strains Exhibiting an N526K Mutation in the ftsI Gene

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01530-06 ◽

2007 ◽

Vol 51 (10) ◽

pp. 3699-3706 ◽

Cited By ~ 7

Author(s):

M. Torrico ◽

L. Aguilar ◽

N. González ◽

M. J. Giménez ◽

O. Echeverría ◽

...

Keyword(s):

Haemophilus Influenzae ◽

Oral Administration ◽

Clavulanic Acid ◽

Bactericidal Activity ◽

Theoretical Calculations ◽

Point Of View ◽

Release Formulation ◽

Extended Release Formulation ◽

Amoxicillin Clavulanic Acid ◽

Free Serum

ABSTRACT The aim of this study was to explore bactericidal activity of total and free serum simulated concentrations after the oral administration of cefditoren (400 mg, twice daily [bid]) versus the oral administration of amoxicillin-clavulanic acid extended release formulation (2,000/125 mg bid) against Haemophilus influenzae. A computerized pharmacodynamic simulation was performed, and colony counts and β-lactamase activity were determined over 48 h. Three strains were used: ampicillin-susceptible, β-lactamase-negative ampicillin-resistant (BLNAR) (also resistant to amoxicillin-clavulanic acid) and β-lactamase-positive amoxicillin-clavulanic acid-resistant (BLPACR) strains, with cefditoren MICs of ≤0.12 μg/ml and amoxicillin-clavulanic acid MICs of 2, 8, and 8 μg/ml, respectively. Against the ampicillin-susceptible and BLNAR strains, bactericidal activity (≥3 log10 reduction) was obtained from 6 h on with either total and free cefditoren or amoxicillin-clavulanic acid. Against the BLPACR strain, free cefditoren showed bactericidal activity from 8 h on. In amoxicillin-clavulanic acid simulations the increase in colony counts from 4 h on occurred in parallel with the increase in β-lactamase activity for the BLPACR strain. Since both BLNAR and BLPACR strains exhibited the same MIC, this was due to the significantly lower (P ≤ 0.012) amoxicillin concentrations from 4 h on in simulations with β-lactamase positive versus negative strains, thus decreasing the time above MIC (T>MIC). From a pharmacodynamic point of view, the theoretical amoxicillin T>MIC against strains with elevated ampicillin/amoxicillin-clavulanic acid MICs should be considered with caution since the presence of β-lactamase inactivates the antibiotic, thus rendering inaccurate theoretical calculations. The experimental bactericidal activity of cefditoren is maintained over the dosing interval regardless of the presence of a mutation in the ftsI gene or β-lactamase production.

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Short- and long-term effects of amoxicillin/clavulanic acid or doxycycline on the gastrointestinal microbiome of growing cats

10.1101/2021.05.28.446115 ◽

2021 ◽

Author(s):

Evangelia Stavroulaki ◽

Jan S. Suchodolski ◽

Rachel Pilla ◽

Geoffrey T. Fosgate ◽

Chi-Hsuan Sung ◽

...

Keyword(s):

Clavulanic Acid ◽

Antibiotic Treatment ◽

Control Group ◽

Rrna Gene ◽

Upper Respiratory Tract ◽

Long Term Effects ◽

Microbial Composition ◽

Increased Risk ◽

Group 15 ◽

Amoxicillin Clavulanic Acid

Antibiotic treatment in early life influences gastrointestinal (GI) microbial composition and function. In humans, the resultant intestinal dysbiosis is associated with an increased risk for certain diseases later in life. The objective of this study was to determine the temporal effects of antibiotic treatment on the GI microbiome of young cats. Fecal samples were collected from cats randomly allocated to receive either amoxicillin/clavulanic acid (20 mg/kg q12h) for 20 days (AMC group; 15 cats) or doxycycline (10 mg/kg q24h) for 28 days (DOX group;15 cats) as part of the standard treatment of upper respiratory tract infection. In addition, feces were collected from healthy control cats (CON group;15 cats). All cats were approximately two months of age at enrolment. Samples were collected on days 0 (baseline), 20 or 28 (AMC and DOX, respectively; last day of treatment), 60, 120, and 300. DNA was extracted and sequencing of the 16S rRNA gene and qPCR assays were performed. Fecal microbial composition was different on the last day of treatment for AMC cats, and 1 month after the end of antibiotic treatment for DOX cats, compared to CON cats. Species richness was significantly greater in DOX cats compared to CON cats on the last day of treatment. Abundance of Enterobacteriales was increased, and that of Erysipelotrichi was decreased in cats of the AMC group on the last day of treatment compared to CON cats. The abundance of the phylum Proteobacteria was increased in cats of the DOX group on days 60 and 120 compared to cats of the CON group. Only minor differences in abundances between the treatment groups and the control group were present on day 300. Both antibiotics appear to delay the developmental progression of the microbiome, and this effect is more profound during treatment with amoxicillin/clavulanic acid and one month after treatment with doxycycline. Future studies are required to determine if these changes influence microbiome function and whether they have possible effects on disease susceptibility in cats.

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Novel Antibiotic Combinations of Diverse Subclasses for Effective Suppression of Extensively Drug-Resistant Methicillin-Resistant Staphylococcus aureus (MRSA)

International Journal of Microbiology ◽

10.1155/2020/8831322 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10

Author(s):

Shumyila Nasir ◽

Muhammad Sufyan Vohra ◽

Danish Gul ◽

Umm E Swaiba ◽

Maira Aleem ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Clavulanic Acid ◽

Antimicrobial Agents ◽

Methicillin Resistant Staphylococcus Aureus ◽

Multidrug Resistant ◽

Methicillin Resistant ◽

Development Of Resistance ◽

Amoxicillin Clavulanic Acid ◽

Combination Antibiotics ◽

Time Kill

The emergence of multidrug-resistant pathogens such as methicillin-resistant Staphylococcus aureus (MRSA), the chief etiological agent for a range of refractory infections, has rendered all β-lactams ineffective against it. The treatment process is further complicated with the development of resistance to glycopeptides, primary antibiotics for treatment of MRSA. Antibiotic combination therapy with existing antimicrobial agents may provide an immediate treatment option. Minimum inhibitory concentrations (MICs) of 18 different commercially available antibiotics were determined along with their 90 possible pairwise combinations and 64 triple combinations to filter out 5 best combinations. Time-Kill kinetics of these combinations were then analyzed to find collateral bactericidal combinations which were then tested on other randomly selected MRSA isolates. Among the top 5 combinations including levofloxacin-ceftazidime; amoxicillin/clavulanic acid-tobramycin; amoxicillin/clavulanic acid-cephradine; amoxicillin/clavulanic acid-ofloxacin; and piperacillin/tazobactam-tobramycin, three combinations were found to be collaterally effective. Levofloxacin-ceftazidime acted synergistically in 80% of the tested clinical MRSA isolates. First-line β-lactams of lower generations can be used effectively against MRSA infection when used in combination. Antibiotics other than glycopeptides may still work in combination.

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Impact of simplified therapeutic guidelines on antibiotic prescriptions: a prospective multicentre comparative study

Journal of Antimicrobial Chemotherapy ◽

10.1093/jac/dkz490 ◽

2019 ◽

Vol 75 (3) ◽

pp. 747-755

Author(s):

Pierre-Marie Roger ◽

Ingrid Peyraud ◽

Michel Vitris ◽

Valérie Romain ◽

Laura Bestman ◽

...

Keyword(s):

Clavulanic Acid ◽

Odds Ratio ◽

Adjusted Odds Ratio ◽

Antibiotic Use ◽

Antibiotic Consumption ◽

Third Generation ◽

Therapeutic Guidelines ◽

Amoxicillin Clavulanic Acid ◽

The Impact ◽

Third Generation Cephalosporins

Abstract Objectives We studied the impact of simplified therapeutic guidelines (STGs) associated with accompanied self-antibiotic reassessment (ASAR) on antibiotic use. Methods Prospective antibiotic audits and feedback took place at 15 hospitals for 12 months, allowing STGs with ≤15 drugs to be devised. STGs were explained to prescribers through sessions referred to as ASAR. Optimal therapy was defined by the conjunction of a diagnosis and the drug specified in the STGs. Analysis of consumption focused on critical drugs: amoxicillin/clavulanic acid, third-generation cephalosporins and fluoroquinolones. Results We compared prescriptions in five hospitals before (n = 179) and after (n = 168) the implementation of STGs + ASAR. These tools were associated with optimal therapies and amoxicillin/clavulanic acid prescriptions [adjusted odds ratio (AOR) 3.28, 95% CI 1.82–5.92 and 2.18, 95% CI 1.38–3.44, respectively] and fewer prescriptions for urine colonization [AOR 0.20 (95% CI 0.06–0.61)]. Comparison of prescriptions (n = 1221) from 10 departments of three clinics with STGs + ASAR for the first quarters of 2018 and 2019 revealed that the prescriptions by 23 ASAR participants more often complied with STGs than those by 28 other doctors (71% versus 60%, P = 0.003). STGs alone were adopted by 10 clinics; comparing the prescriptions (n = 311) with the 5 clinics with both tools, we observed fewer unnecessary therapies in the latter [AOR 0.52 (95% CI 0.34–0.80)]. The variation in critical antibiotic consumption between 2017 and 2018 was −16% for the 5 clinics with both tools and +20% for the other 10 (P = 0.020). Conclusions STGs + ASAR promote optimal antibiotic therapy and reduce antibiotic use.

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Antimicrobial Susceptibility of Subgingival Bacterial Flora in Cats with Gingivitis

Journal of Veterinary Dentistry ◽

10.1177/089875649501200406 ◽

1995 ◽

Vol 12 (4) ◽

pp. 157-160 ◽

Cited By ~ 14

Author(s):

C.E. Harvey ◽

C. Thornsberry ◽

B.R. Miller ◽

F. S. Shofer

Keyword(s):

Clavulanic Acid ◽

Antimicrobial Susceptibility ◽

Antimicrobial Agents ◽

Bacterial Flora ◽

In Vitro Susceptibility ◽

Amoxicillin Clavulanic Acid ◽

Aerobic And Anaerobic

The aerobic and anaerobic flora from gingival pockets of 40 cats with established gingivitis were cultured. The susceptibility of each isolate to four antimicrobial agents currently approved for use in cats (amoxicillin-clavulanic acid; clindamycin; cefadroxil; enrofloxacin) was determined. Amoxicillin-clavulanic acid (Clavamox®) had the highest in-vitro susceptibility against all isolates (92%) and all anaerobes (99% [co-equal with clindamycin]) tested; enrofloxacin (Baytril®) had the highest in-vitro susceptibility against all aerobes (90%) tested.

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Etiological and Resistance Profile of Bacteria Involved in Urinary Tract Infections in Young Children

BioMed Research International ◽

10.1155/2017/4909452 ◽

2017 ◽

Vol 2017 ◽

pp. 1-8 ◽

Cited By ~ 8

Author(s):

Antonio Sorlózano-Puerto ◽

José María Gómez-Luque ◽

Juan de Dios Luna-del-Castillo ◽

José María Navarro-Marí ◽

José Gutiérrez-Fernández

Keyword(s):

Escherichia Coli ◽

Urinary Tract Infection ◽

Urinary Tract ◽

Clavulanic Acid ◽

Total Activity ◽

Geographic Area ◽

E Coli ◽

Amoxicillin Clavulanic Acid ◽

Tract Infections ◽

Reduced Activity

Background.The objective of this study was to identify the bacteria most frequently responsible for urinary tract infection (UTI) in the population of under-2-year-olds in our geographic area and to evaluate the activity of antibiotics widely used for UTI treatment during a 4-year study period.Materials and Methods.A retrospective analysis was conducted of data on the identification and susceptibility of microorganisms isolated in urine samples from children under 2 years of age.Results.A total of 1,045 uropathogens were isolated.Escherichia coliaccounted for the majority (60.3%) of these, followed byEnterococcus faecalis(22.4%) andKlebsiellaspp. (6.5%). The highestE. colisusceptibility rates (>90%) were to piperacillin-tazobactam, cefuroxime, cefotaxime, ceftazidime, imipenem, gentamicin, nitrofurantoin, and fosfomycin, and the lowest were to amoxicillin-clavulanic acid and cotrimoxazole. Among all bacteria isolated, we highlight the overall high activity of piperacillin-tazobactam, imipenem, nitrofurantoin, and fosfomycin against both community and hospital isolates and the reduced activity of amoxicillin-clavulanic acid, cephalosporins, gentamicin, and cotrimoxazole. There was no significant change in the total activity of any of the studied antibiotics over the 4-year study period.Conclusion.Empiric treatment with amoxicillin-clavulanic acid, cotrimoxazole, cephalosporins, and gentamicin may be inadequate due to their limited activity against uropathogens in our setting.

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