In Vitro and In Vivo Activity of Amoxicillin-Clavulanate Combined with Ceftibuten or Cefpodoxime Against Extended-Spectrum β-Lactamase-Producing Escherichia coli and Klebsiella pneumoniae

Infections due to extended-spectrum β-lactamase (ESBL)-producing Enterobacterales are an increasingly common problem. For many of these infections, no oral treatment options are available. The activity of amoxicillin-clavulanate combined with ceftibuten or cefpodoxime was evaluated against a group of Escherichia coli and Klebsiella pneumoniae clinical isolates possessing a variety of CTX-M- and SHV-type ESBLs; some possessed blaTEM1 as well. In time-kill studies, the combination of subinhibitory concentrations of amoxicillin-clavulanate with ceftibuten was bactericidal and synergistic for all strains with an amoxicillin-clavulanate MIC ≤32 μg/mL, regardless of the type of ESBL and the cephalosporin minimal inhibitory concentration (MIC). The combination with cefpodoxime was also bactericidal and synergistic against all but one of these strains. These combinations were further tested against two strains of K. pneumoniae and one E. coli in a sepsis model using Galleria mellonella larvae. The combination of amoxicillin-clavulanate with ceftibuten demonstrated a synergistic survival benefit against all three strains. The combination with cefpodoxime also improved survival against the two K. pneumoniae strains, but not the E. coli strain. These findings support combining amoxicillin-clavulanate with ceftibuten, and possibly cefpodoxime, for the treatment of infections due to ESBL producers and suggest that having an amoxicillin-clavulanate MIC of 32 μg/mL or less may predict activity at clinically achievable concentrations. Clinical studies are warranted to further evaluate this therapeutic approach.

Physical Characterization and In Vitro Evaluation of Dissolution Rate from Cefpodoxime Proxetil Loaded Self Solidifying Solid SNEDDS

BACKGROUND

Cefpodoxime Proxetil (CPD) is a broad-spectrum cephalosporin indicated in respiratory and urinary tract infections. CPD is a BCS class IV drug with pH-dependent solubility and has poor bioavailability. This study investigated the challenges of developing ternary components based on solid SNEDDS of CPD for in vitro dissolution rate enhancement and self-solidifying behaviour.

METHODS

Tween 80, Transcutol and PEG6000 were employed as surfactants, solvents and solidifiers for a base of ternary components to develop self-solidifying solid SNEDDS, respectively. Ternary phase diagrams were used to characterize solidifying behaviour of ternary components in different proportions. S-SNEDDS formulations were drawn on the solidification areas available in the phase diagram and characterized for IR, XRD, DSC and in vitro drug release in various pH media.

RESULTS

Ternary components for the preparation of self-solidifying solid SNEDDS were selected based on drug solubility. FTIR and DSC characterization studies ruled out any drug interaction between CPD and components chosen to prepare S-SNEDDS. CPD was transformed from a crystalline into an amorphous state in ternary dispersions as revealed from XRD data. Optimized formulation (S-S 1) demonstrated more than 95% of drug release irrespective of the pH environments of the medium. Calculation of dissolution efficiency and similarity factors indicate that S SNEDDS resulted in a higher drug dissolution rate over binary dispersion (p<0.01). The stability studies showed that the S SNEDDS were stable in performances and CPD assay.

CONCLUSION

The present investigation provides an alternative approach for enhancing the CPD dissolution rate using self-solidifying solid SNEDDS exhibited solidification behaviour at ambient temperature conditions and drug loading, which could be exploited over conventional dosage form.

Resistance pattern of infected chronic wound isolates and factors associated with bacterial resistance to third generation cephalosporins at Mbarara Regional Referral Hospital, Uganda

BACKGROUND

The objectives of this study were; (I) to determine the proportion of pathogens isolated from patients with infected chronic wounds in the surgical ward of MRRH that are resistant to the third-generation cephalosporins and (II) to determine the factors associated with resistance to third-generation cephalosporins in the surgical ward of MRRH.

METHOD(S)

This study was a descriptive analytical survey of bacterial isolates from infected chronic wounds among patients admitted in the surgical ward of MRRH, Uganda. Seventy five (75) study participants were recruited in the study using convenient sampling technique. Bacterial culture and identification was performed using standard microbiology laboratory procedures whereas broth microdilution method was used to establish the susceptibility of the identified pathogens. Data for objective one (1) was summarized as proportions while the categorized variables were analyzed using logistic regression to determine whether they were associated with the resistance patterns. The level of significance was preset at 5% and p-values less than 0.05 were considered statistically significant.

RESULTS

Generally, all isolates had complete susceptibility (100%) to Cefoperazone+Sulbactam 2g except 7.1% of proteus spp that were resistant. Of all the bacterial isolates studied, Staphylococcus aureus, Enterobacter agglomerans, providencia spp and pseudomonas earuginosa had complete resistance (100%) to Cefopodoxime 200mg while providencia spp and pseudomomas earuginosa had complete resistance (100%) to Cefixime 400mg and cefotaxime 1g. Finally, higher odds of bacterial resistance to more 2 brands of the third generation cephalosporins were observed among participants who had prior exposure to the third generation cephalosporins (OR, 2.22, 95% CI, 0.80-6.14), comorbidities (OR, 1.76, 95% CI, 0.62-4.96) and those who had more than two hospitalizations in a year (OR, 1.39, 95% CI 0.46-4.25). However, multivariate logistic regression was not performed since no factor was significantly associated with resistance to more than two brands of third generation cephalosporins (p >0.05).

CONCLUSION

This study found that cefixime and cefpodoixme had high rates of resistance and should not be used in routine management of infected chronic wounds. In addition, the factors investigated in this study were not significantly associated with bacterial resistance to more than two brands of third generation cephalosporins.

Clavulanate combinations with mecillinam, cefixime or cefpodoxime against ESBL-producing Enterobacterales frequently associated with blaOXA-1 in a paediatric population with febrile urinary tract infections

OBJECTIVES

Oral treatment of febrile urinary tract infections (FUTIs) can be impaired by MDR Enterobacterales often combining ESBL and inhibitor-resistant genes. We studied the impact of β-lactamases and Enterobacterales' genotypes on the cefixime, cefpodoxime and mecillinam ± amoxicillin/clavulanate MICs.

MATERIALS AND METHODS

In this multicentric study, we included 251 previously whole-genome-sequenced ESBL-producing Enterobacterales, isolated in French children with FUTIs. The MICs of cefixime, cefpodoxime, mecillinam alone and combined with amoxicillin/clavulanate were determined and analysed with respect to genomic data. We focused especially on the isolates' ST and their type of β-lactamases. Clinical outcomes of patients who received cefixime + amoxicillin/clavulanate were also analysed.

RESULTS

All isolates were cefixime and cefpodoxime resistant. Disparities depending on blaCTX-M variants were observed for cefixime. The addition of amoxicillin/clavulanate restored susceptibility for cefixime and cefpodoxime in 97.2% (MIC50/90 of 0.38/0.75 mg/L) and 55.4% (MIC50/90 of 1/2 mg/L) of isolates, respectively, whatever the ST, the blaCTX-M variants or the association with inhibitor-resistant β-lactamases (34.2%). All isolates were susceptible to mecillinam + amoxicillin/clavulanate with MIC50/90 of 0.19/0.25 mg/L, respectively. Neither therapeutic failure nor any subsequent positive control urine culture were reported for patients who received cefixime + amoxicillin/clavulanate as an oral relay therapy (n = 54).

CONCLUSIONS

Despite the frequent association of ESBL genes with inhibitor-resistant β-lactamases, the cefixime + amoxicillin/clavulanate MICs remain low. The in vivo efficacy of this combination was satisfying even when first-line treatment was ineffective. Considering the MIC distributions and pharmacokinetic parameters, mecillinam + amoxicillin/clavulanate should also be an alternative to consider when treating FUTIs in children.

Study of the structure and dynamics at various parts of the antibacterial drug molecule cefpodoxime proxetil

The structure and dynamics of cefpodoxime proxetil are elucidated by measuring chemical shift anisotropy (CSA) tensor, spin-lattice relaxation time, and local correlation time at twenty-one crystallographically different 13C nuclei sites. The principal components of CSA tensor of cefpodoxime proxetil are extracted by the two-dimensional phase adjusted sinning sideband (2DPASS) cross-polarization magic angle spinning (CP-MAS) solid-state NMR experiment, and the spin-lattice relaxation time is measured by the method outlined by Torchia(T1CP). The local correlation time is calculated by bearing in mind that the spin-lattice relaxation mechanism of 13C nuclei is mainly governed by the CSA interaction and the heteronuclear dipole-dipole interaction. The aminothiazole ring, β-lactam ring, and dihydrothiazine ring provide stability to the drug molecule and increase the affinity of the drug to penicillin-binding proteins (PBPs) receptors. The principal components of CSA parameters, spin-lattice relaxation time, and local correlation time vary substantially for carbon nuclei residing on these three rings. These signify that not only the electronic environment, but the molecular conformation, and the local dynamics are also altered within the ring. The substitution of the acyl side chain, oxime group, and the aminothiazole ring at the C7 position of the β-lactam ring enhances the antibacterial activity and the binding affinity of the drug. A huge variation of the spin-lattice relaxation time and local correlation time is observed in those regions. The change in the electron charge distribution and nuclear spin dynamics at different parts of the drug molecule is clear by CSA and spin-lattice relaxation measurements, which will enrich the field "NMR crystallography".

Comparison of Complication Rates with Antibiotic Prophylaxis with Cefpodoxime Versus Fluoroquinolones After Transrectal Prostate Biopsy

BACKGROUND

After recommended restriction of the use of fluoroquinolones, the optimal antibiotic prophylaxis for transrectal prostate biopsy is still under debate.

OBJECTIVE

To test the effectiveness of cefpodoxime as oral antibiotic prophylaxis for transrectal prostate biopsies and the complication rates relative to fluoroquinolones.

DESIGN, SETTING, AND PARTICIPANTS

Antibiotic prophylaxis for transrectal prostate biopsies at the Department of Urology at University Hospital Frankfurt was fluoroquinolones for 342 consecutive patients in January 2018 and December 2019 and cefpodoxime for 100 patients from January 2020 to July 2020. Data were prospectively evaluated and retrospectively analyzed. Patients were followed up according to clinical routine at 6 wk after biopsy at the earliest. Patients without follow-up (n = 98) and those receiving antibiotic prophylaxis other than cefpodoxime or fluoroquinolones (n = 15) were excluded.

INTERVENTION

Use of cefpodoxime or fluoroquinolones as antibiotic prophylaxis for transrectal prostate biopsies.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Logistic regression models were used to predict biopsy-related complications according to antibiotic prophylaxis.

RESULTS AND LIMITATIONS

Of 442 patients, 100 (22.6%) received cefpodoxime as antibiotic prophylaxis. Patient baseline and biopsy characteristics were comparable between the cefpodoxime and fluoroquinolone groups. Moreover, there were no differences in the number of prior prostate biopsies or the proportions of systematic vs. fusion biopsies (p > 0.05). There were no differences between the groups in infectious complications such as epididymitis and prostatitis after biopsy. Infectious complication rates were very low, at 2.0% in the cefpodoxime and0.9%fluoroquinolone group. Moreover, there were no differences between the groups in patient-reported complications, such as gross hematuria occurring at more than 5 d after biopsy, hematospermia, or rectal bleeding. In multivariable analyses, after adjustment for patient and prostate biopsy characteristics, cefpodoxime was not associated with higher complication rates than fluoroquinolones (p > 0.05).

CONCLUSIONS

Complications after transrectal prostate biopsies are rare and cefpodoxime might be a sufficient choice as oral antibiotic prophylaxis and noninferior compared to fluoroquinolones.

PATIENT SUMMARY

Cefpodoxime might be a sufficient choice as an easily applicable oral antibiotic prophylaxis for transrectal prostate biopsy. The safety profile of cefpodoxime is comparable to the safety profile of fluoroquinolones.

Spray dried nanospheres for inclusion complexes of cefpodoxime proxetil with β-cyclodextrin, 2-hydroxypropyl-β-cyclodextrin and methyl-β-cyclodextrin: improved dissolution and enhanced antibacterial activity

OBJECTIVE

The aim of the current research was the development hard cellulose capsules containing cefpodoxime proxetil (CEF) (BCS-Class II) encapsulated nanospheres of inclusion complexes with β-CD, HP-β-CD and M-β-CD for efficient antibacterial therapy.

SIGNIFICANCE

The reason for this phenomenon is to bring an innovative approach to effective oral antimicrobial therapy with hard cellulose capsules containing spray dried nanospheres of CEF with β-CD, HP-β-CD and M-β-CD by means of increased solubility, dissolution rate and improved antibacterial efficiency with lower oral dose.

METHODS

Phase solubility analyses was performed to evaluate the drug/CD interaction, involving the stoichiometry and apparent stability constant. Following the preparation of inclusion complexes by spray-drying method, complexes were characterized for physical, solid-state and microbiological analyses. In vitro dissolution from hard cellulose capsules containing CEF and CEF/β-CD, CEF/HP-β-CD and CEF/M-β-CD complexes were performed.

RESULTS

According to AL type phase solubility curves, complexes were formulated as 1:1 molar ratio. The solubility of pure CEF was determined as 0.241 ± 0.002 mg mL-1, the solubility of inclusion complexes increased solubility from 3 to 5 times. The strong host-guest interaction was confirmed for CEF/HP-β-CD and CEF/M-β-CD complexes with SEM, DSC, FT-IR and 1H-NMR analyses. Inclusion complexes were more efficient on bacterial cells (2-4 fold) than pure CEF both Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae. Hard-cellulose capsules filled with inclusion complexes exhibited significantly faster release than unprocessed CEF.

CONCLUSION

Hard-cellulose capsules containing CEF/HP-β-CD and CEF/M-β-CD complexes appear to be superior alternative to commercially available CEF tablets for effective antibacterial therapy.

Repurposing of cefpodoxime proxetil as potent neuroprotective agent through computational prediction and in vitro validation

In recent reports, NR2B-NMDA receptor antagonists showed more research value because of its strong targeting ability and less side effects potential. In 2016, EVT-101 was reported to bind in an almost entirely new binding region of this target. Whether strikingly different binding modes can improve targeting and reduce side effects is worth studying. In our preliminary work, we explored the binding patterns of ifenprodil and EVT-101, found the key amino acids and summarized the pharmacophores, hoping to find such antagonists that target the two binding modes simultaneously. In this study, we developed a scalable virtual screening workflow in the FDA-approved drugs library to identify novel NR2B-NMDAR antagonists based on the combination of two pharmacophores. Cefpodoxime proxetil (5) was identified as the hit compound, and it was found for the first time that 5 might have neuroprotective activity as a NR2B-NMDAR antagonist. This result interested us to make further study, the ligand-receptor interactions modeled by molecular docking studies showed that the compound could perfectly merge both the pharmacophore characteristics of ifenprodil and EVT-101 at the binding cavity between the ATDs of GluN1 and GluN2B. The accuracy of molecular docking results and binding stability of ligand-receptor complexes were validated through 100 ns molecular dynamics simulation and binding free energy calculation. Afterwards, MTT assay (49.8%±0.1%, 5 μM) on NMDA injured SH-SY5Y cells and evidence of the effect on attenuating Ca2+ influx induced by NMDA were applied to validate the computational results, further investigation showed that 5 could suppress the NR2B upregulation induced by NMDA. [Formula: see text] Communicated by Ramaswamy H. Sarma.

Development and characterization of lyophilized cefpodoxime proxetil-Pluronic® F127/polyvinylpyrrolidone K30 solid dispersions with improved dissolution and enhanced antibacterial activity

The aim of this study was the development of hard-cellulose capsules containing cefpodoxime proxetil (CEF) (BCS Class II) loaded novel Pluronic® F127 (P127)/Polyvinylpyrrolidone K30 (PVP) solid dispersions (SDs) using ultrasonic probe induced solvent-lyophilization method for effective antibacterial treatment by means of improved saturated aqueous solubility, dissolution rate, reduced particle size, and wettability. SDs were evaluated for physical and solid-state analyses. The solubility of pure CEF was calculated as 0.269 ± 0.005 mg/mL, SDs formulated with P127/PVP exhibited increased solubility from 3.5- to 8-fold. Molecular distribution of CEF in SDs and formation of CEF loaded amorphous polymeric network were confirmed with morphological study, thermal analysis, Fourier-transform infrared spectroscopy (FT-IR), and 1H-NMR studies. Staphylococcus aureus (ATCC 29213), Escherichia coli (ATCC 25922), and Klebsiella pneumoniae (ATCC 700603) were used to investigate the antibacterial effectiveness of the SDs. The minimum inhibitory concentration (MIC) values of the P127/PVP SDs were found 2-8 times lower than the pure CEF. All SDs from hard-cellulose capsules exhibited significantly faster release than unprocessed CEF. The profiles of SDs and reference were detected to be dissimilar according to difference (f1) and similarity factor (f2). Hard-cellulose capsules containing CEF loaded P127/PVP SDs appear to be feasible alternative to commercially available CEF tablets for effective antibacterial therapy at lowest dose.

Drug Rash With Eosinophilia and Systemic Symptoms (DRESS) Syndrome Probably Related to Cefpodoxime: A Case Report

Cefpodoxime is a common antibiotic with a favorable side effect profile. Drug Rash with Eosinophilia and Systemic Symptoms (DRESS) syndrome has been described with several cephalosporins but not cefpodoxime. We report the probable first case of cefpodoxime-induced DRESS syndrome in a 52-year-old female patient. In our case, the patient presented with symptoms of DRESS syndrome 16 days after initiation of cefpodoxime. This case highlights the necessity of consideration of an iatrogenic reason for presenting signs and symptoms at all times. Reinforcing the importance of taking a thorough drug history and considering drug reactions even if onset of symptoms are delayed.

Ceftazidime-Avibactam Resistance Mutations V240G, D179Y, and D179Y/T243M in KPC-3 β-Lactamase Do Not Alter Cefpodoxime-ETX1317 Susceptibility

Mutations in KPC-2 and KPC-3 β-lactamase can confer resistance to the β-lactam/β-lactamase inhibitor antibacterial intravenous drug combination ceftazidime-avibactam, introduced in 2015. Avibactam was the first of the diazabicyclooctane class of non-β-lactam β-lactamase inhibitors to be approved for clinical use. The orally bioavailable prodrug ETX0282 of the diazabicyclooctane β-lactamase inhibitor ETX1317 is in clinical development in combination with the oral β-lactam prodrug cefpodoxime proxetil for use against complicated urinary tract infections. We investigated the effects of 3 ceftazidime-avibactam resistance mutations in KPC-3 (V240G, D179Y, and D179Y/T243M) on the ability of ETX1317 to overcome KPC-3-induced cefpodoxime resistance. Isogenic Escherichia coli strains, each expressing the wild-type or a mutant KPC-3 at similar levels, retained susceptibility to cefpodoxime-ETX1317 (1:2) with essentially identical minimal inhibitory concentrations of 0.125-0.25 μg/mL cefpodoxime. The KPC-3 mutations had little or no effect on the kinact/Ki values for inhibition by each of 3 diazabicyclooctanes: avibactam, durlobactam (ETX2514), and ETX1317. The KM values for hydrolysis of cefpodoxime were similar for all 4 variants, but the kcat values of the D179Y and D179Y/T243M variants were much lower than those of the wild-type and V240G mutant enzymes. All 4 KPC-3 variants formed stable, reversibly covalent complexes with ETX1317, but dissociation of ETX1317 was much slower from the D179Y and D179Y/T243M mutants than from the wild-type and V240G mutant enzymes. Thus, the KPC-3 variants examined here that cause resistance to ceftazidime-avibactam do not cause resistance to cefpodoxime-ETX1317.

Isolation and characterization of Uropathogenic Escherichia coli (UPEC) from red panda (Ailurus fulgens)

BACKGROUND

Disease prevention and control is a significant part in the ex-situ conservation of the endangered red panda (Ailurus fulgens), being bacterial infection is one of the most important health threats to the captive population. To date, studies about the infection caused by Escherichia coli in the red panda are scarce. This study was conducted to determine the cause of death of a captive red panda through clinical symptoms, complete blood count, biochemical analysis, pathological diagnosis and bacterial whole genome sequencing.

CASE PRESENTATION

The following report describes a case of a 1.5 year old captive red panda (Ailurus fulgens) that was found lethargic and anorectic. She was moved to the quarantine area for daily treatment with 50 mg of Cefpodoxime Proxetil. During the three-day treatment, she did not eat or defecate, and then died. Clinical hematology revealed the values of neutrophils, alanine aminotransferase (ALT), aspartate aminotransferase (AST) and blood urea nitrogen (BUN) were significantly higher. Histological analysis demonstrated major pathological damage in the kidneys, liver and lungs, characterized by hyperemia, parenchymal cell degeneration and necrosis and inflammatory cell infiltration which were predominantly neutrophilic. A bacterial strain confirmed as Escherichia coli was isolated post mortem. Whole genome sequencing of the E. coli showed the complete genome size was 4.99 Mbp. PapA, PapC, OmpA, OmpU and other virulence factors which specific to Uropathogenic Escherichia coli (UPEC) were found in the isolate. Among the virulence factors, P pili, type I pili and related factors of the iron uptake system were associated with nephrotoxicity.

CONCLUSION

The red panda died of bacterial infection caused by an uropathogenic strain of Escherichia coli. The pathogenic mechanisms of the strain are closely related to the expression of specific virulence genes.

Clostridium difficile infection after antibiotic use

Every day, patients are prescribed antibiotics to treat infections, and some of these patients will subsequently develop a superinfection with Clostridium difficile. Although the use of antibiotics is a necessary part of modern medical care, clinicians must be judicious with their use and choice of antibiotics to prevent consequences for patients whenever possible.

Antibiotic susceptibility of cultivable aerobic microbiota from the oral cavity of Echis carinatus from Odisha (India)

During a snake bite, the microbes may get transferred to the bite site and may cause secondary infection along with envenomation. The knowledge on the oral bacterial flora of snakes constitutes information important for snake bite management. The inadequately studied oral microflora of snakes differ geographically, temporally and among the members of the same species. The objective of this study is to determine the pattern of oral bacterial flora of Saw-scaled viper (Echis carinatus) and their susceptibility to antibiotics. Oral swabs were collected from nine healthy Saw-scaled vipers, subjected to microbiological, biochemical and molecular characterization. Additionally, these isolates were subjected to antimicrobial susceptibility testing using ICOSA-20-Plus and ICOSA-20-Minus. A wide range of pathogenic bacteria such as Salmonella arizonae, Pseudomonas stutzeri, Proteus penneri, Alcaligenes faecalis; Citrobacter diversus, C. freundii, Enterococcus faecalis, Bacillus anthracis, Staphylococcus sciuri and Achromobacter xylosoxidans were isolated as new additions to the floral diversity of saw scale viper. Most of the isolates were sensitive towards amikacin, azithromycin, imipenem, ciprofloxacin, gentamicin, ofloxacin, sparfloxacin, tobramycin, levofloxacin, kanamycin, tetracycline, and chloramphenicol while resistant to amoxyclav, cephalothin, cefpodoxime, Co-Trimoxazole, oxacillin and penicillin. The present study revealed that the bacterial flora of the oral cavity of Saw-scaled viper is resistant to many common antibiotics, which are often used for the treatment of snake-bite victims.

Taste-masking and colloidal-stable cubosomes loaded with Cefpodoxime proxetil for pediatric oral delivery

Drug administration failure has been often witnessed in pediatric due to children's resistance to take medicines with bitter taste. Taste-masking is the key requirement among the scanty drugs available for children. Solid taste-masking systems, such as tablets and capsules, are difficult to swallow for children. Therefore, a liquid taste-masking system based on lyotropic liquid crystalline nanoparticles (LLCNs) was developed in this study. Cefpodoxime proxetil (CFP), a typically bitter drug used as antibiotic in pediatric, was selected as the model drug, and the encapsulation of CFP into the LLCNs was envisaged to improve their taste. Pluronic F127 was added to improve the colloidal stability of CFP-LLCNs. The optimized CFP-LLCNs showed the particle size of 187.29 ± 4.12 nm and the encapsulation efficiency of 85.80%. The mesophase analysis by polarized light microscopy and small angle X-ray scattering confirmed the cubic phase of CFP-LLCNs. It showed a sustained-release profile well fitted to Higuchi model, indicating that diffusion and erosion were both responsible for the CFP release. The taste-masking ability of CFP-LLCNs was confirmed by electronic tongue, compared to CFP and commercial product. The colloidal stability was verified after 3 months storage in room condition (25 ± 2 °C, 70 ± 2%RH). To sum up, the taste-masking and colloidal-stable CFP-LLCNs showed great potential for pediatric oral delivery.

Evaluation of prophylactic antibiotic regimens on recurrence and mortality in spontaneous bacterial peritonitis

INTRODUCTION AND OBJECTIVES

Limited data describe current SBP epidemiology and specific secondary SBP prophylactic regimens, leading to variable prescribing practices. This work aims to compare 90-day and one-year SBP recurrence and mortality based on secondary SBP antibiotic prophylaxis regimens.

MATERIALS AND METHODS

We performed a retrospective cohort of patients >18 years with an SBP diagnosis from 2010 to 2015 at two academic institutions. Eligible patients had ascitic PMN counts ≥250cells/mm3 or a positive ascitic culture. Patients were compared based on secondary SBP prophylaxis regimens (i.e., daily, intermittent, or no prophylaxis).

RESULTS

Of 791 patients with ascitic fluid samples, 86 patients were included. Antibiotic prophylaxis included daily (n=34), intermittent (n=36), or no prophylaxis (n=16). Nearly half of SBP episodes had a positive ascitic fluid culture; 50% were gram-negative pathogens, and 50% were gram-positive pathogens. Daily and intermittent regimens had similar rates of recurrence at 90-days (19.4% vs. 14.7%, p=0.60) and one-year (33.3% vs. 26.5%, p=0.53). Similarly, mortality did not differ among daily and intermittent regimens at 90-days (32.4% vs. 30.6%, p=0.87) or one-year (67.6% vs. 63.9%, p=0.74). When comparing any prophylaxis vs. no prophylaxis, there were no differences in 90-day or one-year recurrence or mortality.

CONCLUSIONS

In patients with a history of SBP, our data indicate similar outcomes with daily, intermittent, or no secondary antibiotic prophylaxis. With available data, including ours, demonstrating a changing epidemiology for SBP pathogens, further data is required to determine if traditional approaches to secondary SBP prophylaxis remain appropriate.

Cefpodoxime proxetil as a therapeutic option in switching therapy for infective endocarditis in children: case reports and literature review

Infective endocarditis (IE) is uncommon in children, affecting predominantly subjects with congenital heart disease (CHD) and patients with indwelling central lines. The principles of antibiotic treatment in paediatric population are similar to those in adults. Prolonged intravenous administration of bactericidal rather than bacteriostatic agents is preferred. Outpatient intravenous therapy after initial treatment in the hospital may be considered only in selected patients. Partial oral treatment has been described in cases of left-sided, uncomplicated IE caused by common pathogens in adult patients. There are no guidelines or trials in paediatric population regarding switching therapy from intravenous to oral route. We present two cases of IE in children caused by uncommon pathogenic bacteria (Abiotrophia defectiva and Haemophilus parainfluenzae) successfully treated with oral third-generation cephalosporin - cefpodoxime proxetil after initial intravenous therapy. This paper provides observations on different therapeutic approach for IE in children as well as another potential use of cefpodoxime proxetil.

Isolation and characterization of side-products formed through ∆2-isomerization in the synthesis of cefpodoxime proxetil

In the synthesis of cephalosporin antibiotics, esterified in 4-position, the ∆2-isomerization is a well-known side reaction proceeding under basic conditions. In this work, we investigated the ∆2-isomerization of the esterified cefpodoxime proxetil. Due to the R-configuration and S-configuration of the stereogenic center in the side chain in 4-position, there are two starting materials being diastereomeric to each other. Furthermore, an additional stereogenic center is formed in the isomerization step, thus leading to four possible products. To the best of our knowledge, in this work for the first time the ∆2-isomerization of the two isolated diastereomers of AMCA proxetil, a precursor of cefpodoxime proxetil, as a starting material is reported. It has been shown, that each diastereomer only reacts to one of the two possible ∆2-diastereomers. The synthesis, isolation and characterization of (R)-diastereomers as well as (S)-diastereomers of ∆2-AMCA proxetil and cefpodoxime proxetil, respectively, are presented.

Repeated Isolation of Extended-Spectrum-β-Lactamase-Positive Escherichia coli Sequence Types 648 and 131 from Community Wastewater Indicates that Sewage Systems Are Important Sources of Emerging Clones of Antibiotic-Resistant Bacteria

Antibiotic resistance in bacteria is an emerging problem globally. Resistant bacteria are found in human and animal microbiota, as well as in the environment. Wastewater receives bacteria from all these sources and thus can provide a measurement of abundance and diversity of antibiotic-resistant bacteria circulating in communities. In this study, water samples were collected from a wastewater pump station in a Norwegian suburban community over a period of 15 months. A total of 45 daily samples were cultured and analyzed for the presence of Escherichia coli Eighty E. coli-like colonies were collected from each daily sample and then phenotyped and analyzed for antibiotic resistance using the PhenePlate-AREB system. During the sampling period, two unique E. coli phenotypes with resistance to cefotaxime and cefpodoxime indicating carriage of extended-spectrum β-lactamases (ESBL) were observed repeatedly. Whole-genome sequencing of 15 representative isolates from the two phenotypes identified these as two distinct clones belonging to the two globally spread E. coli multilocus sequence types (STs) ST131 and ST648 and carrying blaCTX-M-15 The number of ESBL-positive E. coli strains in the community wastewater pump station was 314 of 3,123 (10%) analyzed E. coli strains. Of the ESBL-positive isolates, 37% belonged to ST648, and 7% belonged to ST131. Repeated findings of CTX-M-15-positive ST648 and ST131 over time indicate that these STs are resident in the analyzed wastewater systems and/or circulate abundantly in the community.

Levofloxacin versus Cefpodoxime for Antibacterial Prophylaxis in Allogeneic Stem Cell Transplantation

National guidelines recommend antimicrobial prophylaxis for allogeneic stem cell transplant patients during the pre-engraftment period because of increased infection risk during neutropenia. Fluoroquinolones have demonstrated lower rates of bacteremias and incidence of neutropenic fever, but there is limited evidence in the use of alternative antibacterials such as cefpodoxime. The primary objective of this study is to compare the rates of antibiotic prophylaxis failure between levofloxacin and cefpodoxime in allogeneic stem cell transplant recipients. Secondary objectives include comparing and characterizing number and type of infections, mortality at day 100 post-transplant, and hospitalizations for infectious causes in the first 100 days of transplant. This is a single-center, retrospective chart review of adult patients who received an allogeneic stem cell transplant from matched related and matched unrelated donors and antibacterial prophylaxis with levofloxacin or cefpodoxime from January 1, 2011, to October 1, 2014. A total of 142 patients were evaluated (71 levofloxacin, 71 cefpodoxime). Both levofloxacin and cefpodoxime groups had similar rates of neutropenic fever and antibiotic prophylaxis failure (58% versus 58%, P = NS). There were similar incidences of Clostridioides difficile and Multi-drug resistant (MDR) infections among both levofloxacin and cefpodoxime groups. Rates of infections, hospitalizations, and mortality in the first 100 days were similar among both groups. Cefpodoxime can be used as an alternative to levofloxacin for antibiotic prophylaxis in allogeneic stem cell transplant patients.

Cefpodoxime proxetil

A comprehensive profile of cefpodoxime proxetil including the nomenclatures, formulae, elemental composition, appearance, uses, and applications. The methods which were developed for the preparation of the drug substance and their respective schemes are outlined. The physical characteristics of the drug including the ionization constant, solubility, X-ray powder diffraction pattern, differential scanning calorimetry, thermal behavior, and spectroscopic studies are included. The methods which were used for the analysis of the drug substance in bulk drug and/or in pharmaceutical formulations includes the compendial, spectrophotometric, electrochemical and the chromatographic methods. The other studies which was carried out on this drug substance are including the drug stability, pharmacokinetics, bioavailability, drug evaluation, comparison and several compiled reviews. Finally, more than two hundred references are listed at the end of this profile.

In vitro Spectroscopic studies on drug interaction of cefpodoxime proxetil and H2 receptor blockers

One of the relatively advance 3rd generation cephalosporins, cefpodoxime proxetil, is being used all-around. Generally, these are used for the cure of infections allied to urinary and respiratory tract. These cephalosporins have showed a remarkable in vitro activity against many strains of bacteria which are resistant to other orally used active medicinal substances. It is the first oral 3rd generation cephalosporin to be used in the cure of skin infections. The practice of H2 receptor antagonists, concerning lots of treatments recommended in patients with different types of ulcers and allergic urticarial condition, is raising hazards of unwanted secondary outcomes and drug interactions. Learning of in-vitro interaction between cefpodoxime poxetil and H2 blockers (Ranitidine, Famotidine and Cimetidine) were examined applying UV/Visible spectrophotometry and Infrared spectrometry. In the existence of H2 receptor blockers, the cefpodoxime proxetil availability was found to be decreased in vitro only under specific conditions. Furthermore, complexes of Cefpodoxime proxetil-H2 receptor antagonists were manufactured approving the interaction of these drugs. Finally, the above mentioned spectrophotometric techniques were employed to examine the complexes formed (Cefpodoxime proxetil-cimetidine, cefpodoxime proxetil-famotidine and cefpodoxime proxetil-ranitidine).

Development and validation of RP-HPLC method for simultaneous determination of cefpodoxime proxetil and H2 receptor antagonists in pharmaceutical dosage forms

A new method on RP-HPLC is devised and validated, as per ICH guidelines, for the synchronous estimation of cefpodoxime proxetil and H2-receptor antagonits that are Cimetidine, Famotidine and Ranitidine. The method is simple, accurate, expeditious, reproducible, robust and precise. Chromatography was done on a C18 (250 x 4.6mm) column with methanol: water as mobile phae in the ratio of 70:30 (v/v), pumped at a flow rate of 1ml/min and pH was maintained using 85% ortho-phosphoric acid at 3. The λ max 240 nm was preferred for UV detection. A good linear relationship was attained, over the concentration ranges of 20-70 μg/ml and 5-30μg/ml, for cefpodoxime proxetil and H2 blockers respectively, with a correlation coefficient of R= 0.9987 to 0.9992. The method was validated and found precised (i.e. intra day and interday analysis) with RSD <2%. LOD and LOQ observations were under 0.4806 to 2.6069μg/ml which proved the method to be sensitive. The method provided satisfactory results of robustness and reproducibility, when validated and applied successfully for analysis of dosage forms.

Is A Combination of Antibiotics and Non-Steroidal Anti-Inflammatory Drugs More Beneficial Than Antibiotic Monotherapy For The Treatment of Female Acute Uncomplicated Cystitis? A Randomized Controlled Pilot Study

Purpose: To compare the efficacy of non-steroidal anti-inflammatory drugs (NSAIDs) combination therapy to single-agent antibiotic therapy for the resolution of symptoms during two restricted activity days in patients with acute uncomplicated cystitis (AUC)Materials and Methods: We performed a prospective, randomized control pilot study. A total of 55 patients were enrolled. Group I (n=28) was treated with cepodoxime (100 mg twice per day), and Group II (n=27) was treated with cepodoxime (100 mg) and aceclofenac (100 mg) twice per day; both groups were treated for three days. Upon dysuria after each administration, the participants entered a value on a numerical pain scale. The primary outcome was whether there were any differences in the decrease rate in pain scale between the two groups.Result: The average age of the 55 patients was 49.9 ± 13.5 years, and prior to the clinical visit, the patients ex-perienced an average of 2.4 ± 2.2 days of dysuria symptoms. The average numerical pain scale score for dysuria was 4.98 ± 2.18. Thirty-four patients (61.8%) showed positive culture results, and E. coli was the most commonly found bacteria, cultured in 32 patients.Fifty-one patients visited the clinic on day 7, and 42 (76.4%) reported symptom improvement, while nine patients (16.3%) had persistent symptoms. The follow-up numerical pain score was 0.39 ± 1.02 points. The pain score was dramatically decreased after medication. No difference was observed in the magnitude of the pain scale reduction between the two groups (P = 0.134). However, group II showed faster symptom resolution (P = 0.035) at the third administration (day 1.5).Conclusion: Combination therapy with NSAIDs and antibiotics for AUC patients can improve symptoms faster during two restricted activity days when patients have difficulty performing daily living activities.

Roultella ornithinolytica infection in infancy: a case of febrile urinary tract infection

Raoultella ornithinolytica is a Gram-negative, non-motile, encapsulated, aerobic bacillus belonging to the Enterobacteriaceae family. R. ornithinolytica is a not very common, but emergent causal agent of human infection, and its expression of beta-lactamase provides resistance to commonly used antibiotics. The pathogenetic potential of R. ornithinolytica isolates in human disease has become increasingly important. Several cases of hospital-acquired infection, mostly associated with invasive procedures, or in patients with co-morbidity caused by R. ornithinolytica, have been previously reported in the adult population. In pediatric population, two cases in immunocompromised children, one case in an infant with visceral heterotaxy and one case of catheter-related bacteraemia are described. Here, we present the first case of febrile urinary tract infection due to R. ornithinolytica in an 8-month-old infant, recovered from a previous febrile UTI caused by E. coli and without co-morbidity. The empiric therapy with ceftriaxone, followed by cefpodoxime proxetil, resolved symptoms: the clinical condition of the infant improved rapidly and the treatment eradicated urine from the R. ornithinolytica infection. Since other pathogens rather than R. ornithinolytica are usually identified in children with urinary tract infections, including Escherichia coli, Proteus, Klebsiella and Pseudomonas, the identification of this microorganism in our patient's urine was also unexpected.

Antibiotics for recurrent acute pharyngo-tonsillitis: systematic review

The purpose was to determine the current evidence for preferable antibiotic treatment in three common clinical situations with insufficient consensus: Q1: Can antibiotic treatment prevent future attacks of acute pharyngo-tonsillitis (APT) in patients with recurrent APT (RAPT)? Q2: Which antibiotic regimen is preferable in the treatment of APT in patients with RAPT? Q3: Which antibiotic regimen is preferable in the treatment of relapsing APT? Five databases were searched systematically for randomized clinical trials on patients with RAPT with or without current APT or with relapse of APT. Of the unique publications, 643 were found. Five studies addressing Q1 (n = 3) and Q2 (n = 2) met the eligibility criteria. No studies reporting on Q3 were included. Q1: Two studies found that clindamycin and cefpodoxime, respectively, were effective in preventing future APT episodes and in eradicating group A streptococci from the tonsils of RAPT patients. One study found that long-term azithromycin had no effect on the number of APT episodes. Q2: Two studies reported superior clinical and microbiological effects of clindamycin and amoxicillin with clavulanate, respectively, compared to penicillin. The four studies showing superior effects of clindamycin and amoxicillin with clavulanate were assessed to have high risk of bias. Hence, the level of evidence was moderate. There is considerable evidence to suggest that clindamycin and amoxicillin with clavulanate are superior to penicillin with preferable effects on the microbiological flora and the number of future attacks of APT in patients with RAPT. Antibiotic treatment is an option in patients with RAPT, who has contraindications for tonsillectomy.

Increased exposure to extended-spectrum β-lactamase-producing multidrug-resistant Enterobacteriaceae through the consumption of chicken and sushi products

The aim of this study was to determine the occurrence and patterns of resistance of extended-spectrum β-lactamase (ESBL) producing Enterobacteriaceae in food products purchased in Navarra, northern Spain. A total of 174 samples of fish and chicken were analyzed from September 2015 to September 2016, including raw and ready-to-eat products: trout (n = 25), salmon (n = 28), panga (n = 13), chicken nuggets and chicken scalopes (n = 32), sushi (n = 31) and sliced cooked poultry (n = 45). Cefpodoxime-resistant strains were isolated on ChromID ESBL agar and further phenotypic (antimicrobial study on MicroScan© NM37 panel) and genotypic characterization (multiplex PCR, sequencing and multi-locus sequence typing, MLST) was performed to confirm and characterize ESBL producers. Raw chicken and sushi have been determined as the most risky products regarding transmission of ESBL-producing Enterobacteriaceae (occurrence 53.1% and 19.4%, respectively), while sliced cooked poultry products appear to be a safe product in this aspect. With regard to raw fish, prevalence in salmon was lower (3.6%) than in trout and panga (16.0%). Ninety-eight per cent of ESBL isolates (n = 50) show multidrug-resistant profiles, highlighting the high resistances against quinolones and tetracyclines observed in chicken isolates, as well as against ertapenem and chloramphenicol in sushi strains. Predominant β-lactamase type was SHV-12 (50.1%), followed by TEM-type (24.5%) and CTX-M (20.8%). In addition, CTX-M type was only detected in chicken products. The phylogenetic study showed the prevalence of groups A (35%), F (25%) and B1 (15%), usually related to nonvirulent strains. MLST E. coli isolates (n = 20) were grouped into 5 clonal complexes (CC) and 15 sequence types (ST), showing high clonal diversity. ST117 was the prevalent sequence type, while the human pathogen ST131 was not detected in this study. The high prevalence of ESBL-producing multidrug-resistant Enterobacteriaceae detected in products of widespread consumption such as chicken and sushi, increases the concern regarding human exposure to superbugs and encourages the need to improve surveillance of this public health issue.

Development and validation of HPLC method for the determination of Cefpodoxime Proxetil in human plasma

A new, simple, accurate, precise and specific method has been developed for the analysis of Cefpodoxime Proxetil in human plasma. The proposed method was developed and validated with the aim to be used in Bioavailability/Bioequivalence studies for quantification of drug in human plasma. The mobile phase components were acetonitrile, methanol, and water in the ratio of 20:50:30. Ortho phosphoric acid was used to adjust at pH5.0. Flow rate and wavelength were kept 1ml/min and 247nm respectively. The column was C-18 HPLC column 5um particle size, L x 1.d. 25cm x4.6mm. (Supelcosil). Retention time of Cefpodoxime Proxetil was found to be 10.967min. The developed method was validated for selectivity, recovery, accuracy, precision, repeatability, reproducibility, stability and linearity in the range of 0.195mcg/ml to 50mcg/ml. The accuracy and Precision of the proposed method were well within the predefined limits i.e. ±15% for all the calibration standards other than LLOQ (Lower Limit of Quantification) where it was well within ±20% of the nominal value. The analytical recovery was always above 89% showing satisfactory recovery. The coefficient of correlation (R2 ) was 0.999. The developed method was found suitable for the estimation of Cefpodoxime Proxetil in plasma.

Evaluation of the relationship between the minimum inhibitory concentration of ceftiofur and third-generation cephalosporins in Escherichia coli isolates from food-producing animals

To enable future comparison of the antimicrobial susceptibility data between bacteria obtained from animals and humans, it is necessary to compare the relationships between minimum inhibitory concentrations (MICs) of veterinary and human medicine. We evaluated the relationship between the MIC of ceftiofur (CTF) and the MICs of other third-generation cephalosporins (TGCs): cefotaxime (CTX), cefpodoxime (CPDX), and ceftazidime (CAZ), determined by the broth microdilution method using 118 cefazolin-resistant Escherichia coli isolates from food-producing animals. Using the Clinical and Laboratory Standards Institute criteria, very major classification errors were observed only in CAZ (17.8%, 21 of 118); major and minor errors were observed in all TGCs (CTX: 0.8% [1 of 118] and 9.3% [11 of 118]; CPDX: 9.3% [11 of 118] and 6.8% [8 of 118]; CAZ: 2.5% [3 of 118] and 9.3% [11 of 118], respectively). The Spearman correlation coefficients between the MICs of CTF and CTX, CPDX, and CAZ were 0.765, 0.731, and 0.306, respectively. The sensitivity and specificity values were 100.0% and 81.8% for CTX, 99.0% and 27.3% for CPDX, and 76.0% and 86.4% for CAZ compared with CTF. The C-statistic was 0.978 for CTF and CTX, 0.953 for CPDX, and 0.798 for CAZ. For the TGCs evaluated in our study, testing for CTX susceptibility results showed the highest correlation with the results given when testing for CTF susceptibility.

The performance of a resazurin chromogenic agar plate with a combined disc method for rapid screening of extended-spectrum-β-lactamases, AmpC β-lactamases and co-β-lactamases in Enterobacteriaceae

A promising means of rapid screening of extended-spectrum-β-lactamase (ESBL), AmpC β-lactamase, and co-production of ESBL and AmpC that combines resazurin chromogenic agar (RCA) with a combined disc method is here reported. Cefpodoxime (CPD) discs with and without clavulanic acid (CA), cloxacillin (CX) and CA+CX were evaluated against 86 molecularly confirmed β-lactamase-producing Enterobacteriaceae, including 15 ESBLs, 32 AmpCs, nine co-producers of ESBL and AmpC and 30 carbapenemase producers. The CA and CX synergy test successfully detected all ESBL producers (100% sensitivity and 98.6% specificity) and all AmpC producers (100% sensitivity and 96.36% specificity). This assay also performed well in screening for co-existence of ESBL and AmpC (88.89% sensitivity and 100% specificity). The RCA assay is simple and inexpensive and provides results within 7 hr. It can be performed in any microbiological laboratory, in particular, in geographic regions in which ESBL, AmpC or co-β-lactamase-producing Enterobacteriaceae are endemic.

Impact of different organic acids on solubility enhancement of cefpodxime proxetil immediate release tablet and its stability studies

Cefpodoxime proxetil is a third generation cephalosporin antibiotic demonstrates pH dependent solubility and is highly soluble only in acidic pH. The purpose of this investigation was to design and develop immediate release tablets of cefpodoxime proxetil by direct compression method and determine the effect of different solid buffers (organic acids) such as fumaric acid (formulations F1-F4), maleic acid (formulations M1-M4) and citric acid (formulations C1-C4) by using cefpodoxime and acid in the ratios of 4:1, 2:1, 1:1 and 1:2 to achieve pH-independent release of the drug. Physical parameters and assay were found to be within the acceptable range as prescribed in USP 36 / NF 31. In vitro dissolution studies of each formulation were performed in distilled water, USP dissolution medium, HCl buffer solution of pH 1.2, phosphate buffer solutions of pH 4.5 and 6.8 to observe the drug release. The formulations F3, F4, M4 were selected for film coating on the basis of better drug release profile, to protect the drug from chemical degradation through hydrolysis. Film coated formulation F3, F4 and M4 showed a remarkable in vitro release of the drug (72.88±0.43 to 92.67±0.71%) within 30min of observation in all dissolution media and further evaluated by model independent and model dependent approaches. The drug release was found to be best fit to Weibull model as highest r2adjusted (0.924-0.998) and lowest AIC (18.416-54.710) values were obtained in all dissolution media. R Gui® applied for stability studies of F3 and F4 formulations, showing shelf lives of 28 & 27months at ambient and 33 months at accelerated temperatures. Formulation F4 was chosen as best formulation on the basis of physical properties, highest dissolution rate and stability studies.

Validated HPLC method for the pharmacokinetic study of oral extended-release cefpodoxime proxetil chitosan-alginate beads in rabbits

The aim of this study is to develop a simple and applicable HPLC method for the detection of cefpodoxime acid (CFA) in rabbit plasma after oral administration of cefpodoxime proxetil (CFP) loaded chitosan-alginate (CH-ALG) beads formulation. CFP is a prodrug that is deesterified in vivo to its active metabolite CFA to exhibit antibiotic activity. Chromatographic separation of CFA and internal standard (IS) was achieved by a RP18(C18), Phenomenax®100, (250×4.6mm) with the mobile phase consisting of (0.02mol/l (20mM) ammonium acetate solution and acetonitrile (92:8, v/v, pH=4.6) at a flow rate of 1.0ml/min. The method was validated according to the requirements of US-FDA guidelines for bioanalytical method validation. The linear regression analysis for the calibration plots showed good linear relationship (R2=0.9905) in the working concentration range of 0.5-50μg/ml. The limits of detection and quantification (S/N=3) were 0.069 and 0.136μg/ml. Plasma CFA levels were successfully determined in rabbit with satisfactory precision and accuracy. The analyte was found to be stable after a number of stability studies. The proposed HPLC method was successfully applied to pharmacokinetic study in rabbits for CFP loaded CH-ALG beads and marketed immediate release (IR) tablets. All pharmacokinetic parameters were assessed.

Changes in the six most common sequence types of Neisseria gonorrhoeae, including ST4378, identified by surveillance of antimicrobial resistance in northern Taiwan from 2006 to 2013

BACKGROUND

There has been no longitudinal study of drug susceptibility in Neisseria gonorrhoeae in Taiwan since 2006.

METHODS

We collected 1090 gonococcal isolates from Taipei City Hospital, Taiwan from April 2006 to August 2013. We used a disk diffusion assay to determine the susceptibility to five antibiotics and an E-test to determine the minimum inhibitory concentrations for cefixime and ceftriaxone in isolates with resistance. Neisseria gonorrhoeae-multi Antigen Sequence Typing and DNA sequencing of the por and tbpB genes were used to identify sequence types.

RESULTS

Among the 1090 isolates, the resistances to penicillin, ciprofloxacin, cefpodoxime, cefixime, and ceftriaxone were 61.01%, 83.39%, 9.63%, 6.70%, and 2.39%, respectively. The highest minimum inhibitory concentrations of cefixime and ceftriaxone were 0.19 mg/L and 0.50 mg/L, respectively. There were 327 sequence types. The four most common sequence types in homosexuals were ST4378, ST359, ST4654, and ST547; the two most common sequence types in heterosexuals were ST421 and ST419. Each of these sequence types had more than 25 isolates. There were significant differences in the sequence types in patients with different sexual orientations (p < 0.001).

CONCLUSION

Oral cefixime or ceftriaxone injections were used as first-line drugs for the treatment of gonorrhea from 2006 to 2013 because gonorrhea isolates had low minimum inhibitory concentrations for these two drugs. The abrupt emergence of ST4378 (closely related to the notorious ST1407) since 2009 is a cause for alarm. Changes in sexual behavior, including an increase in sexual activity without the use of condoms, may have contributed to the peak in gonorrhea in 2010. Further molecular epidemiological investigations are required.

Investigation of molecular interaction between cefpodoxime acid and human mixtard insulin by ultrasonic and spectral methods

This paper deals with the extensive investigation of molecular interaction between third generation cephalosporin antibiotic, Cefpodoxime Acid (CA) and Human Mixtard Insulin (HMI) in an aqueous medium through ultrasonic, dilute solution viscometric (DSV) and spectral [UV-vis, Attenuated total reflection (ATR)-FT IR] methods at various blend compositions of the drug and insulin at three different (303K, 310K and 313K) temperatures. This is an attempt to unravel the possibility of drug induced hypoglycemic effect. The existence of solute-solute interaction in aqueous solutions of CA and HMI is established from the variation of ultrasonic velocity and other acoustical parameters with blend composition. DSV method is used to confirm the range of blend composition at which the molecular interaction is significant. The conclusions drawn from ultrasonic and DSV methods are further established by the UV-vis and ATR- FT IR spectral studies of ternary mixtures at different blend compositions. Further, the existing interactions suggest the possibility of cefpodoxime acid induced hypoglycemia which is discussed based on the structural aspects of the two components.

ESBL Detection: Comparison of a Commercially Available Chromogenic Test for Third Generation Cephalosporine Resistance and Automated Susceptibility Testing in Enterobactericeae

Rapid detection and reporting of third generation cephalosporine resistance (3GC-R) and of extended spectrum betalactamases in Enterobacteriaceae (ESBL-E) is a diagnostic and therapeutic priority to avoid inefficacy of the initial antibiotic regimen. In this study we evaluated a commercially available chromogenic screen for 3GC-R as a predictive and/or confirmatory test for ESBL and AmpC activity in clinical and veterinary Enterobacteriaceae isolates. The test was highly reliable in the prediction of cefotaxime and cefpodoxime resistance, but there was no correlation with ceftazidime and piperacillin/tazobactam minimal inhibitory concentrations. All human and porcine ESBL-E tested were detected with exception of one genetically positive but phenotypically negative isolate. By contrast, AmpC detection rates lay below 30%. Notably, exclusion of piperacillin/tazobactam resistant, 3GC susceptible K1+ Klebsiella isolates increased the sensitivity and specificity of the test for ESBL detection. Our data further imply that in regions with low prevalence of AmpC and K1 positive E. coli strains chromogenic testing for 3GC-R can substitute for more time consuming ESBL confirmative testing in E. coli isolates tested positive by Phoenix or VITEK2 ESBL screen. We, therefore, suggest a diagnostic algorithm that distinguishes 3GC-R screening from primary culture and species-dependent confirmatory ESBL testing by βLACTATM and discuss the implications of MIC distribution results on the choice of antibiotic regimen.

In vitro/in vivo evaluation of HPMC/alginate based extended-release matrix tablets of cefpodoxime proxetil

The purpose of this research was to assessment of antimicrobial activity and in vitro/in vivo evaluation of cefpodoxime proxetil extended-release (ER) tablet for once daily administration. The tablets were prepared using combination of biodegradable polysaccharides including hydroxypropyl methylcellulose and sodium alginate as matrix material to achieve pH-independent ER release. The tablets were found within the permissible limits for various physicochemical parameters. The in vitro drug release showed that the drug was released over a period of 24h in a sustained release manner. The drug release followed Higuchi kinetics as these plots showed the highest linearity (R(2)=0.9833), but a close relationship was also observed with zero-order kinetics (R(2)=0.9088) and the drug release mechanism was found to be of anomalous or non-Fickian type. Further, in vitro drug release was assessed by antimicrobial assay and it revealed that drug release through 24h periods was above the MIC. In vivo investigation in rabbits showed ER pharmacokinetic profile of cefpodoxime from the matrix tablets. A good correlation of drug absorption in vivo and drug release in vitro (R(2)=0.9785) was observed. These results suggested that the investigated CFP matrix tablets have a potential for extended-release dosage forms.

In Vitro Efficacy of Six Alternative Antibiotics against Multidrug Resistant Escherichia Coli and Klebsiella Pneumoniae from Urinary Tract Infections

INTRODUCTION

Increasing resistance in Escherichia coli and Klebsiella pneumoniae to firstline antibiotics makes therapeutic options for urinary tract infections (UTIs) challenging. This study investigated the in vitro efficacies of 6 antibiotics against multidrug resistant (MDR) uropathogens.

MATERIALS AND METHODS

Minimum inhibitory concentrations to ceftibuten, cefpodoxime, fosfomycin, mecillinam, temocillin, and trimethoprim were determined against 155 MDR-isolates of E. coli and K. pneumoniae. The presence of extended-spectrum beta-lactamases (ESBL) and plasmid-borne AmpC enzymes was determined by phenotypic testing with genotyping performed by multiplex polymerase chain reaction.

RESULTS

Temocillin demonstrated highest susceptibility rates for both E. coli (95%) and K. pneumoniae (95%) when breakpoints for uncomplicated UTIs were applied; however, temocillin susceptibility was substantially lower when "systemic infection" breakpoints were used. Fosfomycin demonstrated the best in vitro efficacy of the orally available agents, with 78% and 69% of E. coli and K. pneumoniae isolates susceptible, respectively. The next most effective antibiotics were ceftibuten (45%) and mecillinam (32%). ESBL and ampC genes were present in 47 (30%) and 59 (38%) isolates.

CONCLUSION

This study demonstrated few oral therapeutic options for MDR-uropathogens, with fosfomycin demonstrating the best in vitro activity.

A SIMPLE AND-SENSITIVE STABILITY-INDICATING UHPLC-DAD METHOD FOR THE DETERMINATION OF CEFETAMET PIVOXIL HYDROCHLORIDE

A fast and sensitive UHPLC-DAD method was developed and subsequently validated for determination of cefetamet pivoxil hydrochloride in the presence of its degradation products. The chromatographic separation was carried out on a Waters Acquity BEH C18, (2.1 x 100 mm, 1.7 µm) column. The mobile phase was composed of 0.1% formic acid and acetonitrile (40 : 60, v/v) at the flow rate 0.7 mL/min. The detection wavelength was 265 nm and the temperature was 30 °C. Cefetamet pivoxil hydrochloride was susceptible to degradation under the influence of sodium hydroxide, hydrochloric acid and in the conditions of increased temperature and relative humidity. However, it was stable after irradiation, in increased temperature in dry air and in the presence of oxidizing agent. The developed UHPLC-DAD method was linear over the concentration range of 10-240 µg/mL (r2 = 0.9999; n = 12). The obtained RSD values were less than 2%, demonstrating that the described procedure is precise. The accuracy was also confirmed (mean recoveries were 97.79-102.08%). Under applied chromatographic conditions LOD and LOQ values were 2.08 mg/mL and 6.29 mg/mL, respectively. The proposed method was successfully applied in determination of cefetamet pivoxil hydrochloride in aqueous solutions as well as in the solid state.

TRIMETHOPRIM-SULFAMETHOXAZOLE RESISTANCE AND FOSFOMYCIN SUSCEPTIBILITY RATES IN UNCOMPLICATED URINARY TRACT INFECTIONS: TIME TO CHANGE THE ANTIMICROBIAL PREFERENCES

Urinary tract infections (UTIs) are among the most common bacterial infections in adult population. They are prevalent in all age groups both in women and men. Also, UTIs are the most frequent indication for empirical antibiotic treatment in emergency department. The aim of this study was to determine the antibiotic resistance rates in the treatment of uncomplicated UTIs. Adult patients admitted to emergency department with uncomplicated UTIs were included in this cross-sectional study. Mid-stream urine samples were obtained under sterile conditions and cultured quantitatively. After 24 hours, the samples showing 10(5) colony forming unit per milliliter (CFU/mL) were tested for antibiotic susceptibility. Resistance to fosfomycin-trometamol (FT), amoxicillin-clavulanic acid (AC), ciprofloxacin (CIP), trimethoprim-sulfamethoxazole (TMP-SMX) and cefpodoxime (CEF) was tested by Kirby-Bauer disc diffusion system. Escherichia (E.) coli accounted for the vast majority (93.4%) of the organisms isolated in the study. Among the E. coli positive patients, resistance to TMP-SMX was the most common antibiotic resistance. The E. coli species detected in our study group were least resistant to FT (2.4%). The resistance rates, especially to CEF, AC and CIP, were significantly higher in patients over 50 years of age. In conclusion, in the treatment of uncomplicated UTIs, TMP-SMX should be excluded from empirical treatment, while fosfomycin could be a viable option in all age groups.

Comparison of 2 chromogenic media for the detection of extended-spectrum β-lactamase producing Enterobacteriaceae stool carriage in nursing home residents

ChromID ESBL agar and Brilliance ESBL agar were compared for the isolation of extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae from 298 stools. These had comparable sensitivity and selectivity for the 116 positive samples. Pre-enrichment with cefpodoxime and extending incubation to 48 hours after direct plating both significantly increased sensitivity but reduced selectivity of both agars.

Stability studies of cefoselis sulfate in the solid state

The process of degradation was studied by using an HPLC-DAD method. Two degradation products were identified with a hybrid ESI-Q-TOF mass spectrometer. The influence of temperature and relative air humidity (RH) on the stability of cefoselis sulfate was investigated. In the solid state at increased RH the degradation of cefoselis sulfate was an autocatalytic reaction of the first order with respect to substrate concentration while in dry air was first-order reaction depending on the substrate concentration. The kinetic and thermodynamic parameters of degradation were calculated.

Evaluation of cefazolin as a surrogate marker for cefpodoxime susceptibility for urinary tract isolates

Of the cephalosporins, cefpodoxime has the most published clinical data for the treatment of urinary tract infections. In 2014, the Clinical and Laboratory Standards Institute (CLSI) guidelines recommended that cefazolin should be used as the surrogate marker for cefpodoxime among urinary tract isolates, replacing cephalothin. This study attempted to determine how well cefazolin serves as the surrogate marker. Additionally, it investigated how cefuroxime compared with cefazolin as a surrogate marker. The MicroScan Walkaway Plus system was used to determine susceptibility for cefazolin and cefuroxime on consecutive urine cultures with a colony count of ≥ 50 000 organisms. Only Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis isolates were included, following CLSI guidelines. Simultaneously, an Etest for cefpodoxime was conducted. The cefpodoxime interpretation was compared with that of the other two agents, and the categorical agreement was calculated, defined as the percentage of identical susceptibility interpretations. Cefazolin (92 %) had a significantly higher categorical agreement than cefuroxime (85 %) among 284 isolates (P = 0.011). The major error rate was 4.4 % for cefazolin and 1.1 % for cefuroxime. The very major error rate was 64 % for cefazolin and 18 % for cefuroxime among the 11 cefpodoxime-resistant isolates. Cefazolin was a better predictor of cefpodoxime susceptibility than the previously recommended agent, cephalothin. However, cefuroxime had better major and very major error rates than cefazolin.

Endocarditis tricuspid sub-aigue of post abortion: report of a case

Tricuspid infective endocarditis is rare and represents five to 10% of all cases of infective endocarditis. It occurs predominantly in intravenous drug users, and patients with central venous catheters or intracardiac probes. We report on the case of subacute tricuspid infective endocarditis in a girl of 17 years. She had no particular cardiovascular history. She was admitted for a persistent fever with cachexy, cough and thoracic pains, and right heart failure that appeared one month after a clandestine abortion. Transthoracic echocardiography found several vegetations on the tricuspid valve with massive tricuspid regurgitation. The chest X-ray showed bilateral excavated lung abscesses and condensation areas. Blood culture was not done and broad-spectrum antibiotic therapy was given. She was apyretic after 10 days. However, the massive tricuspid regurgitation with right heart failure persisted. She was discharged from hospital after 40 days of treatment. Although rare, infective endocarditis is one of the more serious complications of gynaecological procedures, particularly clandestine abortion. Therefore any young girl with persistent fever must be suspected of clandestine abortion.

Chromosomal ampC mutations in cefpodoxime-resistant, ESBL-negative uropathogenic Escherichia coli

AmpC β-lactamase is an enzyme commonly produced by Escherichia coli that causes resistance to cephalosporins and penicillins. Enzyme production is controlled by the strength of the promoter encoded by the chromosomal ampC gene, with the level of production affected by the presence of certain mutations in this region. This study sets out to determine the prevalence of ampC promoter mutations present in a group of uropathogenic E. coli strains. A total of 50 clinical strains of E. coli were collected from urine samples between June 2011 and November 2011. Strains were investigated for the presence of mutations in the chromosomal ampC promoter region by amplification and sequencing of a 271 bp product. The presence of ampC-carrying plasmids derived from other species was also determined, to exclude these from further analysis. ampC-carrying plasmids were found in 10 of the 50 strains, all of which were of the CIT-type. Analysis of the chromosomal ampC promoter region in the 40 remaining strains showed mutations at 16 different positions, with 18 different genotype patterns detected overall. The most common ampC chromosomal mutation, present in 25 of 40 strains, was a T --> A transition at position -32. This mutation has been shown by others to increase enzyme production by up to 46-fold. Altogether, three separate mutations (-32, -42 and -13ins) were present in 90% of the 40 non-plasmid strains, indicating a strong association with the resistance observed. It appears, therefore, that the majority of AmpC-mediated resistance in E. coli can be accounted for by just three point mutations in the chromosome.

[Cutaneous infection with Aggregatibacter actinomycetemcomitans]

BACKGROUND

Aggregatibacter actinomycetemcomitans is a small, gram-negative, non-motile, coccobacillus. Aggregatibacter actinomycetemcomitans is known to cause periodontal disease and to be associated with actinomycosis.

CASE REPORT

We report a patient developed a chronic wound following trauma about the right heel. The lesion resolved after oral antibiotic therapy with cefpodoxime und surgical debridement. Bacterial cultures grew abundant Aggregatibacter actinomycetemcomitans, but no actinomyces species.

OBJECTIVE

The importance of Aggregatibacter actinomycetemcomitans in chronic wounds needs to be explored.