Antibiotics

13 pages, 2026 KiB

Open AccessArticle

Effect of Imipenem and Amikacin Combination against Multi-Drug Resistant Pseudomonas aeruginosa

by Sara Mahmoud Farhan, Mohamed Raafat, Mohammed A. S. Abourehab, Rehab Mahmoud Abd El-Baky, Salah Abdalla, Ahmed Osama EL-Gendy and Ahmed Farag Azmy

Antibiotics 2021, 10(11), 1429; https://doi.org/10.3390/antibiotics10111429 - 22 Nov 2021

Cited by 12 | Viewed by 3970

Abstract

Pseudomonas aeruginosa is an opportunistic nosocomial pathogen associated with high morbidity and mortality rates. Combination of antibiotics has been found to combat multi-drug resistant or extensively drug resistance P. aeruginosa. In this study we investigate the in vitro and in vivo effect [...] Read more.

Pseudomonas aeruginosa is an opportunistic nosocomial pathogen associated with high morbidity and mortality rates. Combination of antibiotics has been found to combat multi-drug resistant or extensively drug resistance P. aeruginosa. In this study we investigate the in vitro and in vivo effect of amikacin and imipenem combination against resistant P. aeruginosa. The checkerboard technique and time-killing curve have been performed for in vitro studies showed synergistic effect for combination. A peritonitis mouse model has been used for evaluation of the therapeutic efficacy of this combination which confirmed this synergistic effect. The in vitro and in vivo techniques showed synergistic interaction between tested drugs with fractional inhibitory concentration indices (FICIs) of ≤0.5. Conventional PCR and quantitative real-time PCR techniques were used in molecular detection of bla _IMP and aac(6′)-Ib as 35.5% and 42.2% of P. aeruginosa harbored bla _IMP and aac(6′)-Ib respectively. Drug combination viewed statistically significant reduction in bacterial counts (p value < 0.5). The lowest bla _IMP and aac(6′)-Ib expression was observed after treatment with 0.25 MIC of imipenem + 0.5 MIC of amikacin. Morphological changes in P. aeruginosa isolates were detected by scanning electron microscope (SEM) showing cell shrinkage and disruption in the outer membrane of P. aeruginosa that were more prominent with combination therapy than with monotherapy. Full article

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12 pages, 711 KiB

Open AccessArticle

Quantifying the Gap between Expected and Actual Rates of Antibiotic Prescribing in British Columbia, Canada

by Ariana Saatchi, Ji-Won Yoo, Kevin L. Schwartz, Michael Silverman, Andrew M. Morris, David M. Patrick, James McCormack and Fawziah Marra

Antibiotics 2021, 10(11), 1428; https://doi.org/10.3390/antibiotics10111428 - 22 Nov 2021

Cited by 4 | Viewed by 2794

Abstract

Despite decades of stewardship efforts to combat antimicrobial resistance and quantify changes in use, the quality of antibiotic use in British Columbia (BC) remains unknown. As the overuse and misuse of antibiotics drives antibiotic resistance, it is imperative to expand surveillance efforts to [...] Read more.

Despite decades of stewardship efforts to combat antimicrobial resistance and quantify changes in use, the quality of antibiotic use in British Columbia (BC) remains unknown. As the overuse and misuse of antibiotics drives antibiotic resistance, it is imperative to expand surveillance efforts to examine the quality of antibiotic prescriptions. In late 2019, Canadian expected rates of antibiotic prescribing were developed for common infections. These rates were utilized to quantify the gap between the observed rates of prescribing and Canadian expected rates for antibiotic use for the province of BC. The prescribing data were extracted and matched to physician billing systems using anonymized patient identifiers from 1 January 2000 to 31 December 2018. Outpatient prescribing was further subdivided into community and emergency department settings and stratified by the following age groups: <2 years, 2–18 years, and ≥19 years. The proportions of physician visits that received antibiotic prescription were compared against the Canadian expected rates to quantify the unnecessary use for 18 common indications. Respiratory tract infections (RTI), including acute bronchitis, acute sinusitis, and acute pharyngitis, reported significant levels of overprescribing. Across all ages and health care settings, prescribing for RTI indications occurred at rates 2–8 times higher than the expected rates recommended by a group of expert Canadian physicians. Understanding the magnitude of unnecessary prescribing is a first step in delineating the provincial prescribing quality. The quantification of antibiotic overuse offers concrete targets for provincial stewardship efforts to reduce unnecessary prescribing by an average of 30% across both outpatient and emergency care settings. Full article

(This article belongs to the Special Issue Antibiotics Research in Canada)

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17 pages, 807 KiB

Open AccessArticle

Effects of Bacillus amyloliquefaciens LFB112 on Growth Performance, Carcass Traits, Immune, and Serum Biochemical Response in Broiler Chickens

by Marhaba Ahmat, Junhao Cheng, Zaheer Abbas, Qiang Cheng, Zhen Fan, Baseer Ahmad, Min Hou, Ghenijan Osman, Henan Guo, Junyong Wang and Rijun Zhang

Antibiotics 2021, 10(11), 1427; https://doi.org/10.3390/antibiotics10111427 - 22 Nov 2021

Cited by 25 | Viewed by 2852

Abstract

This study aimed to investigate the effects of Bacillus amyloliquefaciens LFB112 on the growth performance, carcass traits, immune response, and serum biochemical parameters of broiler chickens. A total of 396 1 day old, mixed-sex commercial Ross 308 broilers with similar body weights were [...] Read more.

This study aimed to investigate the effects of Bacillus amyloliquefaciens LFB112 on the growth performance, carcass traits, immune response, and serum biochemical parameters of broiler chickens. A total of 396 1 day old, mixed-sex commercial Ross 308 broilers with similar body weights were allotted into six treatment groups. The assigned groups were the CON group (basal diet with no supplement), AB (antibiotics) group (basal diet + 150 mg of aureomycin/kg), C+M group (basal diet + 5 × 10⁸ CFU/kg B. amyloliquefaciens LFB112 powder with vegetative cells + metabolites), C group (basal diet + 5 × 10⁸ CFU/kg B. amyloliquefaciens LFB112 vegetative cell powder with removed metabolites), M group (basal diet + 5 × 10⁸ CFU/kg B. amyloliquefaciens LFB112 metabolite powder with removed vegetative cells), and CICC group (basal diet + 5 × 10⁸ CFU/kg Bacillus subtilis CICC 20179). Results indicated that chickens in the C+M, C, and M groups had higher body weight (BW) and average daily gain (ADG) (p < 0.05) and lower feed conversion ratio (FCR) (p = 0.02) compared to the CON group. The C+M group showed the lowest abdominal fat rate compared to those in the CON, AB, and CICC groups (p < 0.05). Compared to the CON group, serum IgA and IgG levels in the C+M, C, and M groups significantly increased while declining in the AB group (p < 0.05). B. amyloliquefaciens LFB112 supplementation significantly reduced the serum triglyceride, cholesterol, urea, and creatinine levels, while increasing the serum glucose and total protein (p < 0.05). In conclusion, B. amyloliquefaciens LFB112 significantly improved the growth performance, carcass traits, immunity, and blood chemical indices of broiler chickens and may be used as an efficient broiler feed supplement. Full article

(This article belongs to the Topic Novel Antimicrobial Agents: Discovery, Design and New Therapeutic Strategies)

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10 pages, 616 KiB

Open AccessArticle

Effect of Antimicrobial Stewardship on Oral Quinolone Use and Resistance Patterns over 8 Years (2013–2020)

by Atsushi Uda, Katsumi Shigemura, Koichi Kitagawa, Kayo Osawa, Mari Kusuki, Yonmin Yan, Ikuko Yano and Takayuki Miyara

Antibiotics 2021, 10(11), 1426; https://doi.org/10.3390/antibiotics10111426 - 22 Nov 2021

Cited by 3 | Viewed by 2123

Abstract

Since 2014, several global and national guidelines have been introduced to address the problem of antimicrobial resistance. We conducted a campaign in a tertiary hospital to promote appropriate quinolone use through educational lectures in 2018. The aim of this retrospective study was to [...] Read more.

Since 2014, several global and national guidelines have been introduced to address the problem of antimicrobial resistance. We conducted a campaign in a tertiary hospital to promote appropriate quinolone use through educational lectures in 2018. The aim of this retrospective study was to evaluate the changes in the following: prescription characteristics, trend of oral quinolone use, and antibiotic susceptibility of bacteria from 2013 to 2020. Antimicrobial use was assessed as days of therapy per 1000 patient-days. We found a significant reduction in unnecessary antibiotic prescriptions between December 2013 and December 2020. Significant negative trends were detected in the use of quinolones over 8 years (outpatients, coefficient = −0.15655, p < 0.001; inpatients, coefficient = −0.004825, p = 0.0016). In particular, the monthly mean use of quinolones among outpatients significantly decreased by 11% from 2013 to 2014 (p < 0.05) and reduced further by 31% from 2017 to 2020 (p < 0.001). A significant positive trend was observed in the susceptibility of Pseudomonas aeruginosa to levofloxacin (p < 0.001). These results demonstrate that the use of oral quinolones was further reduced following educational intervention and the bacterial susceptibility improved with optimal quinolone usage compared to that in 2013. Full article

(This article belongs to the Special Issue The Equal Power of Antibiotics and Antimicrobial Resistance: The Continuing Development of New Knowledge)

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12 pages, 762 KiB

Open AccessArticle

Procalcitonin Increase Is Associated with the Development of Critical Care-Acquired Infections in COVID-19 ARDS

by Owen Richards, Philip Pallmann, Charles King, Yusuf Cheema, Charlotte Killick, Emma Thomas-Jones, Jessica Harris, Catherine Bailey and Tamas Szakmany

Antibiotics 2021, 10(11), 1425; https://doi.org/10.3390/antibiotics10111425 - 22 Nov 2021

Cited by 21 | Viewed by 3655

Abstract

Secondary bacterial infection in COVID-19 patients is associated with increased mortality and disproportionately affects critically ill patients. This single-centre retrospective observational study investigates the comparative efficacy of change in procalcitonin (PCT) and other commonly available biomarkers in revealing or predicting microbiologically proven secondary [...] Read more.

Secondary bacterial infection in COVID-19 patients is associated with increased mortality and disproportionately affects critically ill patients. This single-centre retrospective observational study investigates the comparative efficacy of change in procalcitonin (PCT) and other commonly available biomarkers in revealing or predicting microbiologically proven secondary infection in critical COVID-19 patients. Adult patients admitted to an intensive care unit (ICU) with confirmed SARS-CoV-2 infection between 9 March 2020 and 5 June 2020 were recruited to the study. For daily biomarker and secondary infection, laboratory-confirmed bloodstream infection (LCBI) and ventilator-associated pneumonia/tracheobronchitis (VAP/VAT) data were collected. We observed a PCT rise in 53 (81.5%) of the patients, a C-reactive protein (CRP) rise in 55 (84.6%) and a white blood cell count (WBC) rise in 61 (93.8%). Secondary infection was confirmed in 33 (50.8%) of the patients. A PCT rise was present in 97.0% of patients with at least one confirmed VAP/VAT and/or LCBI event. CRP and WBC rises occurred in 93.9% and 97.0% of patients with confirmed VAP/VAT and/or LCBI, respectively. Logistic regression analysis found that, when including all biomarkers in the same model, there was a significant association between PCT rise and the occurrence of LCBI and/or VAP/VAT (OR = 14.86 95%CI: 2.20, 342.53; p = 0.021). Conversely, no statistically significant relationship was found between either a CRP rise (p = 0.167) or a WBC rise (p = 0.855) and the occurrence of VAP/VAT and/or LCBI. These findings provide a promising insight into the usefulness of PCT measurement in predicting the emergence of secondary bacterial infection in ICU. Full article

(This article belongs to the Special Issue Antimicrobial Use and Stewardship during the COVID-19 Era)

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12 pages, 2709 KiB

Open AccessArticle

A Systematic Study of the Antibacterial Activity of Basidiomycota Crude Extracts

by Marco Clericuzio, Mattia Bivona, Elisa Gamalero, Elisa Bona, Giorgia Novello, Nadia Massa, Francesco Dovana, Emilio Marengo and Elisa Robotti

Antibiotics 2021, 10(11), 1424; https://doi.org/10.3390/antibiotics10111424 - 21 Nov 2021

Cited by 11 | Viewed by 2604

Abstract

The excessive consumption of antibiotics in clinical, veterinary and agricultural fields has resulted in tremendous flow of antibiotics into the environment. This has led to enormous selective pressures driving the evolution of antimicrobial resistance genes in pathogenic and commensal bacteria. In this context, [...] Read more.

The excessive consumption of antibiotics in clinical, veterinary and agricultural fields has resulted in tremendous flow of antibiotics into the environment. This has led to enormous selective pressures driving the evolution of antimicrobial resistance genes in pathogenic and commensal bacteria. In this context, the World Health Organization (WHO) has promoted research aiming to develop medical features using natural products that are often competitive with synthetic drugs in clinical performance. Fungi are considered an important source of bioactive molecules, often effective against other fungi and/or bacteria, and thus are potential candidates in the search of new antibiotics. Fruiting bodies of sixteen different fungal species of Basidiomycota were collected in the Italian Alps. The identification of fungal species was performed through Internal Transcribed Spacer (ITS) sequencing. Most species belong to genera Cortinarius, Mycena and Ramaria, whose metabolite contents has been scarcely investigated so far. The crude extracts obtained from the above mushrooms were tested for their inhibition activity against five human pathogens: Candida albicans ATCC 14053, C. glabrata ATCC 15126, Staphylococcus aureus NCTC 6571, Pseudomonas aeruginosa ATCC 27853 and Klebsiella pneumoniae ATCC 13883. Twelve crude extracts showed activity against P. aeruginosa ATCC 27853. Highest activity was shown by some Cortinarius species, as C. nanceiensis. Full article

(This article belongs to the Special Issue Anti-microbial Activity of Metabolites Isolated from Fungi)

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11 pages, 1791 KiB

Open AccessArticle

Application of Bacteriophages on Shiga Toxin-Producing Escherichia coli (STEC) Biofilm

by Nicola Mangieri, Roberto Foschino and Claudia Picozzi

Antibiotics 2021, 10(11), 1423; https://doi.org/10.3390/antibiotics10111423 - 20 Nov 2021

Cited by 9 | Viewed by 2575

Abstract

Shiga toxin-producing Escherichia coli are pathogenic bacteria able to form biofilms both on abiotic surfaces and on food, thus increasing risks for food consumers. Moreover, biofilms are difficult to remove and more resistant to antimicrobial agents compared to planktonic cells. Bacteriophages, natural predators [...] Read more.

Shiga toxin-producing Escherichia coli are pathogenic bacteria able to form biofilms both on abiotic surfaces and on food, thus increasing risks for food consumers. Moreover, biofilms are difficult to remove and more resistant to antimicrobial agents compared to planktonic cells. Bacteriophages, natural predators of bacteria, can be used as an alternative to prevent biofilm formation or to remove pre-formed biofilm. In this work, four STEC able to produce biofilm were selected among 31 different strains and tested against single bacteriophages and two-phage cocktails. Results showed that our phages were able to reduce biofilm formation by 43.46% both when used as single phage preparation and as a cocktail formulation. Since one of the two cocktails had a slightly better performance, it was used to remove pre-existing biofilms. In this case, the phages were unable to destroy the biofilms and reduce the number of bacterial cells. Our data confirm that preventing biofilm formation in a food plant is better than trying to remove a preformed biofilm and the continuous presence of bacteriophages in the process environment could reduce the number of bacteria able to form biofilms and therefore improve the food safety. Full article

(This article belongs to the Special Issue Antibiotics vs. Phage Therapy)

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12 pages, 706 KiB

Open AccessArticle

Prescription of Aminoglycosides in 23 French Neonatal Intensive Care Units

by Séverine Martin-Mons, Béatrice Gouyon, Séverine Lorrain, Soumeth Abasse, Cénéric Alexandre, Guillaume Binson, Roselyne Brat, Laurence Caeymaex, Yvan Couringa, Cécile Desbruyeres, Marine Dorsi-Di Meglio, Guillaume Escourrou, Florence Flamein, Olivier Flechelles, Olivier Girard, Elsa Kermorvant-Duchemin, Alexandre Lapillonne, Catherine Lafon, Massimo Di Maio, Gaël Mazeiras, Julien Mourdie, Amélie Moussy-Durandy, Anne-Sophie Pages, Duksha Ramful, Hasinirina Razafimahefa, Jean-Marc Rosenthal, Silvia Iacobelli and Jean-Bernard Gouyon Show full author list Hide full author list

Antibiotics 2021, 10(11), 1422; https://doi.org/10.3390/antibiotics10111422 - 20 Nov 2021

Cited by 2 | Viewed by 2569

Abstract

Background: Aminoglycosides are the most prescribed antibiotics in neonatal intensive care units (NICU). Reducing exposure to antibiotics in the NICU is highly desirable, particularly through benchmarking methods. Methods: Description of aminoglycosides prescriptions in 23 French NICU using the same computerized system over [...] Read more.

Background: Aminoglycosides are the most prescribed antibiotics in neonatal intensive care units (NICU). Reducing exposure to antibiotics in the NICU is highly desirable, particularly through benchmarking methods. Methods: Description of aminoglycosides prescriptions in 23 French NICU using the same computerized system over a 4-year period (2017–2020). A benchmarking program of antibiotics prescription was associated. Results: The population included 53,818 patients. Exposition rates to gentamicin and amikacin were 31.7% (n = 17,049) and 9.1% (n = 4894), respectively. Among neonates exposed to gentamicin, 90.4% of gentamicin and 77.6% of amikacin treatments were started within the 1st week of life. Among neonates exposed to amikacin, 77.6% started amikacin within the 1st week. The average daily dose of gentamicin at first prescription increased over the study period from 3.9 in 2017 to 4.4 mg/kg/d in 2020 (p < 0.0001). Conversely, the corresponding amikacin daily doses decreased from 13.0 in 2017 to 12.3 mg/kg/d in 2020 (p = 0.001). The time interval between the first 2 doses of gentamicin was mainly distributed in 3 values during the first week of life: 49.4% at 24 h, 26.4% at 36 h, and 22.9% at 48 h. At first amikacin prescription, the time interval was distributed in 4 categories: 48% at 24 h, 4.1% at 30 h, 8.5% at 36 h, and 37.1% at 48 h. As compared to literature guidelines, the rates of overdose and underdose in gentamicin (1.5% and 2.7%) and amikacin (0.3% and 1.0%). They significantly decreased for gentamicin over the study period. In multivariate analysis, the factors significantly associated with GENT overdose were the year of admission, prematurity, length of stay, and duration of the treatment. Conclusion: This prescription strategy ensured a low rate of overdose and underdose, and some benefits of the benchmarking program is suggested. Full article

(This article belongs to the Special Issue Antimicrobial Agents Used in Intensive Care Unit)

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11 pages, 1457 KiB

Open AccessArticle

Cerebrospinal Fluid Concentrations of Meropenem and Vancomycin in Ventriculitis Patients Obtained by TDM-Guided Continuous Infusion

by Christoph Tiede, Ute Chiriac, Daniel Dubinski, Florian J. Raimann, Otto R. Frey, Anka C. Röhr, Anna Wieduwilt, Michael Eibach, Natalie Filmann, Christian Senft, Kai Zacharowski, Volker Seifert and Jan Mersmann

Antibiotics 2021, 10(11), 1421; https://doi.org/10.3390/antibiotics10111421 - 20 Nov 2021

Cited by 8 | Viewed by 3764

Abstract

Effective antibiotic therapy of cerebral infections such as meningitis or ventriculitis is hindered by low penetration into the cerebrospinal fluid (CSF). Because continuous infusion of meropenem and vancomycin and routine therapeutic drug monitoring (TDM) have been proposed to optimize antimicrobial exposure in ventriculitis [...] Read more.

Effective antibiotic therapy of cerebral infections such as meningitis or ventriculitis is hindered by low penetration into the cerebrospinal fluid (CSF). Because continuous infusion of meropenem and vancomycin and routine therapeutic drug monitoring (TDM) have been proposed to optimize antimicrobial exposure in ventriculitis patients, an individualized dosing strategy was implemented in our department. We present a retrospective analysis of meropenem and vancomycin concentrations in serum and CSF in the first nine ventriculitis patients treated with continuous infusion and TDM-guided dose optimization aiming at 20–30 mg/L. Median initial dosing was 8.8 g/24 h meropenem and 4.25 g/24 h vancomycin, respectively, resulting in median serum concentrations of 21.3 mg/L for meropenem and 24.5 mg/L for vancomycin and CSF concentrations of 3.4 mg/L for meropenem and 1.7 mg/L for vancomycin. Median CSF penetration was 15% for meropenem and 7% for vancomycin. With initial dosing, all but one patient achieved CSF concentrations above 1 mg/L. Dose adjustment according to TDM ensured sufficient CSF concentrations in all patients within 48 h of treatment. Given the limited penetration, continuous infusion of meropenem and vancomycin based on renal function and TDM-guided dose optimization appears a reasonable approach to attain sufficient CSF concentrations in ventriculitis patients. Full article

(This article belongs to the Special Issue TDM, Individual Dosing and Application of Antibiotics/Antiinfectives in Critically Ill Patients)

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18 pages, 11034 KiB

Open AccessArticle

Collagen Hydrogels Loaded with Silver Nanoparticles and Cannabis Sativa Oil

by Pablo Edmundo Antezana, Sofia Municoy, Claudio Javier Pérez and Martin Federico Desimone

Antibiotics 2021, 10(11), 1420; https://doi.org/10.3390/antibiotics10111420 - 20 Nov 2021

Cited by 31 | Viewed by 4781

Abstract

Wounds represent a major healthcare problem especially in hospital-associated infections where multi-drug resistant strains are often involved. Nowadays, biomaterials with therapeutic molecules play an active role in wound healing and infection prevention. In this work, the development of collagen hydrogels loaded with silver [...] Read more.

Wounds represent a major healthcare problem especially in hospital-associated infections where multi-drug resistant strains are often involved. Nowadays, biomaterials with therapeutic molecules play an active role in wound healing and infection prevention. In this work, the development of collagen hydrogels loaded with silver nanoparticles and Cannabis sativa oil extract is described. The presence of the silver nanoparticles gives interesting feature to the biomaterial such as improved mechanical properties or resistance to collagenase degradation but most important is the long-lasting antimicrobial effect. Cannabis sativa oil, which is known for its anti-inflammatory and analgesic effects, possesses antioxidant activity and successfully improved the biocompatibility and also enhances the antimicrobial activity of the nanocomposite. Altogether, these results suggest that this novel nanocomposite biomaterial is a promising alternative to common treatments of wound infections and wound healing. Full article

(This article belongs to the Special Issue Antimicrobial Activity of Medical Materials)

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13 pages, 582 KiB

Open AccessArticle

Pattern and Appropriateness of Antimicrobial Prescriptions for Upper Respiratory Tract and Dental Infections in Male Prisoners in Italy

by Gabriella Di Giuseppe, Raffaele Lanzano, Armando Silvestro, Francesco Napolitano and Maria Pavia

Antibiotics 2021, 10(11), 1419; https://doi.org/10.3390/antibiotics10111419 - 20 Nov 2021

Cited by 11 | Viewed by 2537

Abstract

Background: This study explored the antimicrobial prescribing pattern for upper respiratory tract and dental infections in prisoners in Italy, with specific attention paid to the appropriateness of indication and its potential determinants. Methods: This investigation was conducted through the consultation of clinical records [...] Read more.

Background: This study explored the antimicrobial prescribing pattern for upper respiratory tract and dental infections in prisoners in Italy, with specific attention paid to the appropriateness of indication and its potential determinants. Methods: This investigation was conducted through the consultation of clinical records of adult male inmates in a prison in the south of Italy. Results: Prescription of antimicrobials for upper respiratory tract infections ranged from 41.9% in influenza diagnoses to 88% in pharyngitis diagnoses, with high prevalence also for bronchitis (73.5%) and common cold (57.7%), and those for dental infections ranged from 82% in pulp necrosis and symptomatic apical periodontitis/pulp necrosis and localized acute apical abscess diagnoses, to 85.7% in symptomatic irreversible pulpitis with or without symptomatic apical periodontitis diagnoses. The most frequently prescribed antimicrobial was amoxicillin and clavulanic acid (33.8%), followed by amoxicillin (26.5%), macrolides (19.8%) and third-generation cephalosporins (7.9%). The overall antimicrobial overprescription was 69.4%, whereas an antimicrobial prescription was provided in all 52 cases in which it was indicated. The inappropriate antimicrobial prescriptions were significantly less likely for bronchitis, influenza and symptomatic irreversible pulpitis with or without symptomatic apical periodontitis compared to common cold/pharyngitis/rhinosinusitis, and when the antimicrobial prescription was provided by medical specialists compared to prison physicians, whereas antimicrobial overprescriptions without indications were significantly more frequent in patients with underlying chronic clinical conditions. Conclusions: A concerning widespread practice of inappropriate antimicrobial prescriptions in prisoners was found. Diagnoses-specific monitoring of antimicrobial use and prison-focused antimicrobial stewardship policies are strongly needed. Full article

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12 pages, 448 KiB

Open AccessArticle

Susceptibility to Nisin, Bactofencin, Pediocin and Reuterin of Multidrug Resistant Staphylococcus aureus, Streptococcus dysgalactiae and Streptococcus uberis Causing Bovine Mastitis

by Samantha Bennett, Laila Ben Said, Pierre Lacasse, François Malouin and Ismail Fliss

Antibiotics 2021, 10(11), 1418; https://doi.org/10.3390/antibiotics10111418 - 19 Nov 2021

Cited by 20 | Viewed by 3415

Abstract

Antibiotics are the most effective strategy to prevent and treat intramammary infections. However, their misuse has led to the dissemination of multidrug resistant bacteria (MDR) for both animals and humans. Efforts to develop new alternative strategies to control bacterial infections related to MDR [...] Read more.

Antibiotics are the most effective strategy to prevent and treat intramammary infections. However, their misuse has led to the dissemination of multidrug resistant bacteria (MDR) for both animals and humans. Efforts to develop new alternative strategies to control bacterial infections related to MDR are continuously on the rise. The objective of this study was to evaluate the antimicrobial activity of different bacteriocins and reuterin against MDR Staphylococcus and Streptococcus clinical isolates involved in bovine mastitis. A bacterial collection including S. aureus (n = 19), S. dysgalactiae (n = 17) and S. uberis (n = 19) was assembled for this study. Antibiotic resistance profiles were determined by the disk diffusion method. In addition, sensitivity to bacteriocins and reuterin was evaluated by determining minimum inhibitory concentrations (MIC). A total of 21 strains (37.5%) were MDR. MICs ranged from ≤1.0

μ

g/mL to ≥100

μ

g/mL for nisin and 2.0 to ≥250

μ

g/mL for bactofencin. Reuterin was active against all tested bacteria, and MICs vary between 70 and 560

μ

g/mL. Interestingly, 20 MDR strains were inhibited by bactofencin at a concentration of ≤250

μ

g/mL, while 14 were inhibited by nisin at an MIC of ≤100

μ

g/mL. Pediocin did not show an inhibitory effect. Full article

(This article belongs to the Special Issue Antimicrobial Resistance and Antibiotic Alternatives in Livestock)

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10 pages, 11792 KiB

Open AccessArticle

Global Spread and Molecular Characterization of CTX-M-Producing Salmonella Typhimurium Isolates

by Lili Guo and Yongda Zhao

Antibiotics 2021, 10(11), 1417; https://doi.org/10.3390/antibiotics10111417 - 19 Nov 2021

Cited by 7 | Viewed by 2350

Abstract

This study aimed to determine the global prevalence and molecular characterization of CTX-M-producing Salmonella Typhimurium isolates. A total of 330 (15.2%, 330/21779) bla_CTX-M-positive S. Typhimurium were obtained from the public databases in July 2021. Thirteen variants were found in the [...] Read more.

This study aimed to determine the global prevalence and molecular characterization of CTX-M-producing Salmonella Typhimurium isolates. A total of 330 (15.2%, 330/21779) bla_CTX-M-positive S. Typhimurium were obtained from the public databases in July 2021. Thirteen variants were found in the 330 members of the bla_CTX-M group, and bla_CTX-M-9 (26.4%, 88/330) was the most prevalent. The majority of bla_CTX-M-positive S. Typhimurium were obtained from humans (59.7%, 197/330) and animals (31.5%, 104/330). The number of bla_CTX-M-positive S. Typhimurium increased annually (p < 0.0001). These isolates were primarily found from China, the United Kingdom, Australia, the USA, and Germany. In addition, these isolates possessed 14 distinct sequence types (ST), and three predominated: ST34 (42.7%, 141/330), ST19 (37.0%, 122/330), and ST313 (10.3%, 34/330). The majority of ST34 S. Typhimurium isolates were distributed in China and mainly from swine. However, the majority of ST19 were distributed in the United Kingdom and Australia. Analysis of contigs showed that the major type of bla_CTX-M-carrying plasmid was identified as IncI plasmid (52.9%, 27/51) and IncHI2 plasmid (17.6%, 9/51) in 51 bla_CTX-M-positive S. Typhimurium isolates. In addition, WGS analysis further revealed that bla_CTX-M co-existed with nine antibiotic-resistant genes with a detection rate over 50%, conferring resistance to five classes of antimicrobials. The 154 virulence genes were detected among these isolates, of which 107 virulence genes were highly common. This study revealed that China has been severely contaminated by bla_CTX-M-positive S. Typhimurium isolates, these isolates possessed numerous ARGs and virulence genes, and highlighted that continued vigilance for bla_CTX-M-positive S. Typhimurium in animals and humans is urgently needed. Full article

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14 pages, 1004 KiB

Open AccessArticle

Distribution and Clonal Diversity of Staphylococcus aureus and Other Staphylococci in Surface Waters: Detection of ST425-t742 and ST130-t843 mecC-Positive MRSA Strains

by Vanessa Silva, Eugénia Ferreira, Vera Manageiro, Lígia Reis, María Teresa Tejedor-Junco, Ana Sampaio, José Luis Capelo, Manuela Caniça, Gilberto Igrejas and Patrícia Poeta

Antibiotics 2021, 10(11), 1416; https://doi.org/10.3390/antibiotics10111416 - 19 Nov 2021

Cited by 21 | Viewed by 3356

Abstract

Natural aquatic environments represent one of the most important vehicles of bacterial dissemination. Therefore, we aimed to isolate staphylococci from surface waters and to investigate the presence of antimicrobial resistance genes and virulence factors as well as the genetic lineages of all Staphylococcus [...] Read more.

Natural aquatic environments represent one of the most important vehicles of bacterial dissemination. Therefore, we aimed to isolate staphylococci from surface waters and to investigate the presence of antimicrobial resistance genes and virulence factors as well as the genetic lineages of all Staphylococcus aureus isolates. Staphylococci were recovered from water samples collected from 78 surface waters, including rivers, streams, irrigation ditches, dams, lakes, and fountains. The presence of antimicrobial resistance genes and virulence factors was investigated by PCR. Multilocus sequence typing and spa-typing were performed in all S. aureus isolates. From the 78 water samples, 33 S. aureus, one S. pseudintermedius, and 51 coagulase-negative staphylococci (CoNS) were identified. Among the S. aureus isolates, four MRSA were identified, and all harbored the mecC gene. Fourteen S. aureus were susceptible to all antimicrobials tested and the remaining showed resistance to penicillin, erythromycin and/or tetracycline encoded by the blaZ, ermT, msr(A/B), tetL, and vgaA genes. Regarding the clonal lineages, one mecC-MRSA isolate belonged to spa-type t843 and sequence type (ST) 130 and the other three to t742 and ST425. The remaining S. aureus were ascribed 14 spa-types and 17 sequence types. Eleven species of CoNS were isolated: S. sciuri, S. lentus, S. xylosus, S. epidermidis, S. cohnii spp. urealyticus, S. vitulinus, S. caprae, S. carnosus spp. Carnosus, S. equorum, S. simulans, and S. succinus. Thirteen CoNS isolates had a multidrug resistance profile and carried the following genes: mecA, msr(A/B), mph(C), aph(3′)-IIIa, aac(6′)-Ie–aph(2′’)-Ia, dfrA, fusB, cat_pC221, and tetK. A high diversity of staphylococci was isolated from surface waters including mecCMRSA strains and isolates presenting multidrug-resistance profiles. Studies on the prevalence of antibiotic-resistant staphylococci in surface waters are still very scarce but extremely important to estimate the contribution of the aquatic environment in the spread of these bacteria. Full article

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8 pages, 265 KiB

Open AccessArticle

Resistance to 16-Membered Macrolides, Tiamulin and Lincomycin in a Swine Isolate of Acholeplasma laidlawii

by María M. Tavío, Ana S. Ramírez, Carlos Poveda, Rubén S. Rosales, Cristina F. Malla and José B. Poveda

Antibiotics 2021, 10(11), 1415; https://doi.org/10.3390/antibiotics10111415 - 19 Nov 2021

Cited by 1 | Viewed by 1965

Abstract

Acholeplasma (A.) laidlawii is an opportunistic pathogen with the ability to disseminate resistance determinants to antibiotics; however, its resistance to macrolides has been less studied. The aim of the present study was to characterize the mechanisms responsible for the resistance to [...] Read more.

Acholeplasma (A.) laidlawii is an opportunistic pathogen with the ability to disseminate resistance determinants to antibiotics; however, its resistance to macrolides has been less studied. The aim of the present study was to characterize the mechanisms responsible for the resistance to macrolides, tiamulin and lincomycin found in a strain of A. laidlawii isolated from a pig with pneumonia. MICs of erythromycin, 15- and 16-membered macrolides, tiamulin and lincomycin were determined by microdilution method with and without reserpine, an inhibitor of ABC efflux pumps and regions of the genome were sequenced. Reserpine only decreased lincomycin MIC but it did not change the MICs of macrolides and tiamulin. The analysis of the DNA sequence of 23S rRNA showed nucleotide substitutions at eight different positions, although none of them were at positions previously related to macrolide resistance. Five mutations were found in the L22 protein, one of them at the stop codon. In addition, two mutations were found in the amino acid sequence of L4. The combination of multiple mutations in the ribosomal proteins L22 and L4 together with substitutions in 23S rRNA DNA sequence was associated with the resistance to macrolides, the pleuromutilin and lincomycin in the studied A. laidlawii strain. Full article

(This article belongs to the Special Issue One Health in Mycoplasmas: Antimicrobial Susceptibility and Resistance in Mycoplasmas Infecting Humans, Animals, Plants and Insects)

8 pages, 495 KiB

Open AccessArticle

Predictor of Early Administration of Antibiotics and a Volume Resuscitation for Young Infants with Septic Shock

by Osamu Nomura, Takateru Ihara, Yoshihiko Morikawa, Hiroshi Sakakibara, Yuho Horikoshi and Nobuaki Inoue

Antibiotics 2021, 10(11), 1414; https://doi.org/10.3390/antibiotics10111414 - 19 Nov 2021

Cited by 3 | Viewed by 2071

Abstract

(1) Background: It is critical to administer antibiotics and fluid bolus within 1 h of recognizing sepsis in pediatric patients. This study aimed to identify the predictor of the successful completion of a 1-h sepsis bundle for infants with suspected sepsis. (2) Methods: [...] Read more.

(1) Background: It is critical to administer antibiotics and fluid bolus within 1 h of recognizing sepsis in pediatric patients. This study aimed to identify the predictor of the successful completion of a 1-h sepsis bundle for infants with suspected sepsis. (2) Methods: This is an observational study using a prospective registry including febrile young infants (aged < 90 days) who visited a pediatric emergency department with a core body temperature of 38.0 °C or higher and 36.0 °C or lower. Univariate and logistic regression analyses were conducted to determine the predictor (s) of successful sepsis bundle completion. (3) Results: Of the 323 registered patients, 118 patients with suspected sepsis were analyzed, and 38 patients (32.2%) received a bundle-compliant treatment. Among potential variables, such as age, sex, and vital sign parameters, the logistic regression analysis showed that heart rate (odds ratio: OR 1.02; 95% confidence interval: 1.00–1.04) is a significant predictor of the completion of a 1-h sepsis bundle. (4) Conclusions: We found that tachycardia facilitated the sepsis recognition and promoted the successful completion of a 1-h sepsis bundle for young infants with suspected septic shock and a possible indicator for improving the quality of the team-based sepsis management. Full article

(This article belongs to the Special Issue Antibiotic Usage in Acute Situations)

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16 pages, 1625 KiB

Open AccessArticle

Antitrypanosomal Activity of Anthriscus Nemorosa Essential Oils and Combinations of Their Main Constituents

by Cecilia Baldassarri, Giulia Falappa, Eugenia Mazzara, Laura Acquaticci, Elena Ossoli, Diego Romano Perinelli, Giulia Bonacucina, Stefano Dall’Acqua, Loredana Cappellacci, Filippo Maggi, Farahnaz Ranjbarian, Anders Hofer and Riccardo Petrelli

Antibiotics 2021, 10(11), 1413; https://doi.org/10.3390/antibiotics10111413 - 18 Nov 2021

Cited by 6 | Viewed by 2139

Abstract

This study aimed to investigate the susceptibility of Trypanosoma brucei to the Anthriscus nemorosa essential oils (EOs), isolated compounds from these oils, and artificial mixtures of the isolated compounds in their conventional and nanoencapsulated forms. The chemical composition of the essential oils from [...] Read more.

This study aimed to investigate the susceptibility of Trypanosoma brucei to the Anthriscus nemorosa essential oils (EOs), isolated compounds from these oils, and artificial mixtures of the isolated compounds in their conventional and nanoencapsulated forms. The chemical composition of the essential oils from the aerial parts and roots of Anthriscus nemorosa, obtained from a wild population growing in central Italy, were analyzed by gas chromatography/mass spectrometry (GC/MS). In both cases, the predominant class of compounds was monoterpene hydrocarbons, which were more abundant in the EOs from the roots (81.5%) than the aerial parts (74.0%). The overall results of this work have shed light on the biological properties of A. nemorosa EO from aerial parts (EC₅₀ = 1.17 μg/mL), farnesene (EC₅₀ = 0.84 μg/mL), and artificial mixtures (Mix 3–5, EC₅₀ in the range of 1.27 to 1.58 μg/mL) as relevant sources of antiprotozoal substances. Furthermore, the pool measurements of ADP (adenosine diphosphate) and NTPs (nucleoside triphosphates) in the cultivated bloodstream form of trypanosomes exposed to different concentrations of EOs showed a disturbed energy metabolism, as indicated by increased pools of ADP in comparison to ATP (adenosine triphosphate) and other NTPs. Ultimately, this study highlights the significant efficacy of A. nemorosa EO to develop long-lasting and effective antiprotozoal formulations, including nanoemulsions. Full article

(This article belongs to the Special Issue Antiprotozoal Activity of Natural Products)

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18 pages, 3009 KiB

Open AccessArticle

Root Canal Disinfection Articles with the Highest Relative Citation Ratios. A Bibliometric Analysis from 1990 to 2019

by Pilar Valderrama, Pilar Baca, Carmen Solana and Carmen María Ferrer-Luque

Antibiotics 2021, 10(11), 1412; https://doi.org/10.3390/antibiotics10111412 - 18 Nov 2021

Cited by 7 | Viewed by 2300

Abstract

The relative citation rate (RCR) is a normalized article-level metric useful to assess the impact of research articles. The objective of this bibliometric study is to identify and analyze, in root canal disinfection, the 100 articles having the highest RCRs in the period [...] Read more.

The relative citation rate (RCR) is a normalized article-level metric useful to assess the impact of research articles. The objective of this bibliometric study is to identify and analyze, in root canal disinfection, the 100 articles having the highest RCRs in the period 1990–2019, then compare them with the top 100 articles most cited. A cross-sectional study was performed, and the search strategy ((Disinfection AND root canal) AND ((“1990/01/01”[Date-Publication]: “2019/12/31”[Date-Publication]))) relied on PubMed (n = 4294 documents), and article data were downloaded from the iCite database. The 100 articles with the highest RCRs and the top 100 cited were selected and evaluated in bibliometric terms. Among the 100 articles with the highest RCRs, there were no differences in the three decades for RCRs values, but there were in citations, being 2000–2009 the most cited. The USA was the predominant country (n = 30), followed by Brazil (n = 14). The most frequent study designs were reviews (n = 27) and in vitro (n = 25) and ex vivo (n = 24) studies. All subfields were well represented, although they varied over time. In 2010–2019, regenerative procedures and irrigation/disinfection techniques were predominant. Considering the RCR’s top 100 articles, 76 were common with the 100 most cited articles. Using the RCR metric allowed us to identify influential articles in root canal disinfection, a research field with topics of significance that fluctuate over time. Compared to citations, RCR reduces the time from publication to detection of its importance for the readership and could be a valid alternative to citation counts. Full article

(This article belongs to the Section Antibiofilm Strategies)

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15 pages, 3622 KiB

Open AccessArticle

Genomic Characterization of a Proteus sp. Strain of Animal Origin Co-Carrying bla_NDM-1 and lnu(G)

by Ying Li, Yichuan Qiu, Junping She, Xu Wang, Xiaoyi Dai and Luhua Zhang

Antibiotics 2021, 10(11), 1411; https://doi.org/10.3390/antibiotics10111411 - 18 Nov 2021

Cited by 7 | Viewed by 2269

Abstract

The emergence of carbapenem-resistant Proteus represents a serious threat to global public health due to limited antibiotic treatment options. Here, we characterize a Proteus isolate NMG38-2 of swine origin that exhibits extensive drug resistance, including carbapenems. Whole-genome sequencing based on Illumina and MinION [...] Read more.

The emergence of carbapenem-resistant Proteus represents a serious threat to global public health due to limited antibiotic treatment options. Here, we characterize a Proteus isolate NMG38-2 of swine origin that exhibits extensive drug resistance, including carbapenems. Whole-genome sequencing based on Illumina and MinION platforms showed that NMG38-2 contains 24 acquired antibiotic resistance genes and three plasmids, among which, pNDM_NMG38-2, a pPvSC3-like plasmid, is transferable and co-carries bla_NDM-1 and lnu(G). Sequence analysis of pPvSC3-like plasmids showed that they share a conserved backbone but have a diverse accessory module with complex chimera structures bearing abundant resistance genes, which are facilitated by transposons and/or homologous recombination. The acquisition of bla_NDM-1 in pNDM_NMG38-2 was due to the ISCR1-mediated integration event. Comprehensive analysis of the lnu(G)-bearing cassettes carried by bacterial plasmids or chromosomes revealed a diversification of its genetic contexts, with Tn6260 and ISPst2 elements being the leading contributors to the dissemination of lnu(G) in Enterococcus and Enterobacteriaceae, respectively. In conclusion, this study provides a better understanding of the genetic features of pPvSC3-like plasmids, which represent a novel plasmid group as a vehicle mediating the dissemination of bla_NDM-1 among bacteria species. Moreover, our results highlight the central roles of Tn6260 and ISPst2 in the spread of lnu(G). Full article

(This article belongs to the Special Issue Bacterial Drug Resistance and Transmission Mechanism)

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15 pages, 2136 KiB

Open AccessArticle

Is There a Difference in Clinical Features, Microbiological Epidemiology and Effective Empiric Antimicrobial Therapy Comparing Healthcare-Associated and Community-Acquired Vertebral Osteomyelitis?

by Siegmund Lang, Astrid Frömming, Nike Walter, Viola Freigang, Carsten Neumann, Markus Loibl, Martin Ehrenschwender, Volker Alt and Markus Rupp

Antibiotics 2021, 10(11), 1410; https://doi.org/10.3390/antibiotics10111410 - 18 Nov 2021

Cited by 16 | Viewed by 3756

Abstract

Background: Empiric antibiotic therapy for suspected vertebral osteomyelitis (VO) should be initiated immediately in severely ill patients, and might be necessary for culture-negative VO. The current study aimed to identify differences between community-acquired (CA) and healthcare-associated (HA) VO in terms of clinical presentation, [...] Read more.

Background: Empiric antibiotic therapy for suspected vertebral osteomyelitis (VO) should be initiated immediately in severely ill patients, and might be necessary for culture-negative VO. The current study aimed to identify differences between community-acquired (CA) and healthcare-associated (HA) VO in terms of clinical presentation, causative pathogens, and antibiotic susceptibility. Methods: Cases of adult patients with VO treated at a German university orthopaedic trauma center between 2000 and 2020 were retrospectively reviewed. Patient history was used to distinguish between CA and HA VO. Susceptibility of antibiotic regimens was assessed based on antibiograms of the isolated pathogens. Results: A total of 155 patients (with a male to female ratio of 1.3; and a mean age of 66.1 ± 12.4 years) with VO were identified. In 74 (47.7%) patients, infections were deemed healthcare-associated. The most frequently identified pathogens were Staphylococcus aureus (HAVO: 51.2%; CAVO: 46.8%), and Coagulase-negative Staphylococci (CoNS, HAVO: 31.7%; CAVO: 21.3%). Antibiograms of 45 patients (HAVO: n = 22; CAVO: n = 23) were evaluated. Significantly more methicillin-resistant isolates, mainly CoNS, were found in the HAVO cohort (27.3%). The highest rate of resistance was found for cefazolin (HAVO: 45.5%; CAVO: 26.1%). Significantly higher rates of resistances were seen in the HAVO cohort for mono-therapies with meropenem (36.4%), piperacillin–tazobactam (31.8%), ceftriaxone (27.3%), and co-amoxiclav (31.8%). The broadest antimicrobial coverage was achieved with either a combination of piperacillin–tazobactam + vancomycin (CAVO: 100.0%; HAVO: 90.9%) or meropenem + vancomycin (CAVO: 100.0%; HAVO: 95.5%). Conclusion: Healthcare association is common in VO. The susceptibility pattern of underlying pathogens differs from CAVO. When choosing an empiric antibiotic, combination therapy must be considered. Full article

(This article belongs to the Special Issue Trends in Antibiotic Resistance in the Hospital Setting and Its Impact on Public Health)

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19 pages, 2932 KiB

Open AccessArticle

High Genomic Identity between Clinical and Environmental Strains of Herbaspirillum frisingense Suggests Pre-Adaptation to Different Hosts and Intrinsic Resistance to Multiple Drugs

by Willian Klassen Oliveira, Hugo Leonardo Ávila, Michelle Zibeti Tadra, Rodrigo Luiz Cardoso, Cyntia Maria Teles Fadel-Pichet, Emanuel Maltempi de Souza, Fábio de Oliveira Pedrosa and Helisson Faoro

Antibiotics 2021, 10(11), 1409; https://doi.org/10.3390/antibiotics10111409 - 18 Nov 2021

Cited by 4 | Viewed by 2408

Abstract

The genus Herbaspirillum is widely studied for its ability to associate with grasses and to perform biological nitrogen fixation. However, the bacteria of the Herbaspirillum genus have frequently been isolated from clinical samples. Understanding the genomic characteristics that allow these bacteria to switch [...] Read more.

The genus Herbaspirillum is widely studied for its ability to associate with grasses and to perform biological nitrogen fixation. However, the bacteria of the Herbaspirillum genus have frequently been isolated from clinical samples. Understanding the genomic characteristics that allow these bacteria to switch environments and become able to colonize human hosts is essential for monitoring emerging pathogens and predicting outbreaks. In this work, we describe the sequencing, assembly, and annotation of the genome of H. frisingense AU14559 isolated from the sputum of patients with cystic fibrosis, and its comparison with the genomes of the uropathogenic strain VT-16–41 and the environmental strains GSF30, BH-1, IAC152, and SG826. The genes responsible for biological nitrogen fixation were absent from all strains except for GSF30. On the other hand, genes encoding virulence and host interaction factors were mostly shared with environmental strains. We also identified a large set of intrinsic antibiotic resistance genes that were shared across all strains. Unlike other strains, in addition to unique genomic islands, AU14559 has a mutation that renders the biosynthesis of rhamnose and its incorporation into the exopolysaccharide unfeasible. These data suggest that H. frisingense has characteristics that provide it with the metabolic diversity needed to infect and colonize human hosts. Full article

(This article belongs to the Special Issue Antimicrobial Resistance (AMR) in Plant and Soil Microbiome)

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8 pages, 2398 KiB

Open AccessArticle

Complete Genome Sequences of Klebsiella michiganensis and Citrobacter farmeri, KPC-2-Producers Serially Isolated from a Single Patient

by Jehane Y. Abed, Maxime Déraspe, Ève Bérubé, Matthew D’Iorio, Ken Dewar, Maurice Boissinot, Jacques Corbeil, Michel G. Bergeron and Paul H. Roy

Antibiotics 2021, 10(11), 1408; https://doi.org/10.3390/antibiotics10111408 - 18 Nov 2021

Cited by 6 | Viewed by 2534

Abstract

Carbapenemase-producing Enterobacterales, including KPC-2 producers, have become a major clinical problem. During an outbreak in Quebec City, Canada, KPC-2-producing Klebsiella michiganensis and Citrobacter farmeri were isolated from a patient six weeks apart. We determined their complete genome sequences. Both isolates carried nearly identical [...] Read more.

Carbapenemase-producing Enterobacterales, including KPC-2 producers, have become a major clinical problem. During an outbreak in Quebec City, Canada, KPC-2-producing Klebsiella michiganensis and Citrobacter farmeri were isolated from a patient six weeks apart. We determined their complete genome sequences. Both isolates carried nearly identical IncN2 plasmids with blaKPC-2 on a Tn4401b element. Both strains also carried IncP1 plasmids, but that of C. farmeri did not carry a Beta-lactamase gene, whereas that of K. michiganensis carried a second copy of bla_KPC-2 on Tn4401b. These results suggest recent plasmid transfer between the two species and a recent transposition event. Full article

(This article belongs to the Special Issue Carbapenemase-Producing Enterobacterales)

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13 pages, 1996 KiB

Open AccessArticle

Ozonation of Amoxicillin and Ciprofloxacin in Model Hospital Wastewater to Increase Biotreatability

by Severina Aleksić, Andreja Žgajnar Gotvajn, Katarina Premzl, Mitja Kolar and Sonja Šostar Turk

Antibiotics 2021, 10(11), 1407; https://doi.org/10.3390/antibiotics10111407 - 17 Nov 2021

Cited by 18 | Viewed by 3131

Abstract

Amoxicillin (AMX) and Ciprofloxacin (CIP) are antibiotics commonly used in human medicine with high environmental toxicity and poor biodegradability. They have been found in various hospital effluents and groundwater, and their environmental impact is still not fully understood. In this work, we investigated [...] Read more.

Amoxicillin (AMX) and Ciprofloxacin (CIP) are antibiotics commonly used in human medicine with high environmental toxicity and poor biodegradability. They have been found in various hospital effluents and groundwater, and their environmental impact is still not fully understood. In this work, we investigated the possibility of treating model wastewaters containing the antibiotics AMX and CIP using ozonation, with the addition of H₂O₂ under various conditions, including different pH values, H₂O₂, and ozone dosages. The quantification of and treatment efficacy for antibiotic removal were determined via solid phase extraction followed by chromatographic separation by liquid chromatography coupled with tandem triple quadrupole mass spectrometry (LC/MS/MS). This analytical system is quite efficient for the detection of all major antibiotic classes, even if they are present at very low concentrations. The efficiency of ozonation was determined by measuring the TOC (Total Organic Carbon) changes after ozonation of the model wastewater and by measuring the concentration of the two antibiotics. In a sequential activated sludge process of ozone-treated model wastewater, almost complete TOC removal and an overwhelming decrease in antibiotic concentrations (up to 99%) were observed. Ozonation resulted in complete removal of AMX and CIP in less than 30 and 120 min, respectively. The results of this work indicate that ozonation could be a suitable pretreatment method to reduce the toxicity of contaminants (AMX and CIP) and improve the biodegradability of hospital wastewater. Full article

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23 pages, 4806 KiB

Open AccessReview

Mechanisms of Resistance to Macrolide Antibiotics among Staphylococcus aureus

by Maria Miklasińska-Majdanik

Antibiotics 2021, 10(11), 1406; https://doi.org/10.3390/antibiotics10111406 - 17 Nov 2021

Cited by 58 | Viewed by 14248

Abstract

Methicillin resistant Staphylococcus aureus strains pose a serious treatment problem because of their multi-drug resistance (MDR). In staphylococcal strains, resistance to macrolides, lincosamides, and streptogramin B (MLS_B) correlates with resistance to methicillin. The rapid transmission of erm genes responsible for MLS [...] Read more.

Methicillin resistant Staphylococcus aureus strains pose a serious treatment problem because of their multi-drug resistance (MDR). In staphylococcal strains, resistance to macrolides, lincosamides, and streptogramin B (MLS_B) correlates with resistance to methicillin. The rapid transmission of erm genes responsible for MLS_B resistance has strongly limited the clinical application of traditional macrolides such as erythromycin. On the other hand, in the age of increasing insensitivity to antibiotics the idea of implementing a therapy based on older generation drugs brings hope that the spread of antibiotic resistance will be limited. A thorough understanding of the resistance mechanisms contributes to design of antibiotics that avoid bacterial insensitivity. This review highlights the mechanisms of action of macrolides and mechanism of resistance to these antibiotics among Staphylococcus aureus. Full article

(This article belongs to the Special Issue Molecular Mechanisms of Antibiotic Resistance in Staphylococcus aureus)

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10 pages, 254 KiB

Open AccessArticle

The Impact of the SARS-Cov2 Pandemic on a Persuasive Educational Antimicrobial Stewardship Program in a University Hospital in Southern Italy: A Pre-Post Study

by Margherita Macera, Lorenzo Onorato, Federica Calò, Caterina Monari, Rosa Annibale, Giuseppe Signoriello, Giovanna Donnarumma, Maria Vittoria Montemurro, Massimiliano Galdiero and Nicola Coppola

Antibiotics 2021, 10(11), 1405; https://doi.org/10.3390/antibiotics10111405 - 16 Nov 2021

Cited by 13 | Viewed by 2123

Abstract

Objectives: We evaluated the effect of the pandemic on the disruption of a persuasive educational antimicrobial stewardship program (ASP) conducted in a university hospital in southern Italy. Methods: In March 2020, the ASP, which began in January 2017 and was carried out at [...] Read more.

Objectives: We evaluated the effect of the pandemic on the disruption of a persuasive educational antimicrobial stewardship program (ASP) conducted in a university hospital in southern Italy. Methods: In March 2020, the ASP, which began in January 2017 and was carried out at different times in 10 wards, was stopped due to the COVID-19 pandemic. We conducted an observational study with interrupted time series analysis to compare the antibiotic consumption and costs, average length of hospital stay and in-hospital mortality between 12 months before and 9 months after the interruption. Results: Four medical, four surgical wards and two ICUs were included in the study, for a total of 35,921 patient days. Among the medical wards we observed after the interruption a significant increase in fluoroquinolone use, with a change in trend (CT) of 0.996, p = 0.027. In the surgical wards, we observed a significant increase in the overall consumption, with a change in level (CL) of 24.4, p = 0.005, and in the use of third and fourth generation cephalosporins (CL 4.7, p = 0.003). In two ICUs, we observed a significant increase in piperacillin/tazobactam and fluoroquinolone consumption (CT 9.28, p = 0.019, and 2.4, p = 0.047). In the wards with a duration of ASP less than 30 months, we observed a significant increase in antibiotic consumption in the use of piperacillin/tazobactam and fluoroquinolones (CT 12.9, p = 0.022: 4.12, p = 0.029; 1.004, p = 0.011). Conclusions: The interruption of ASP during COVID-19 led to an increase in the consumption of broad-spectrum antibiotics, particularly in surgical wards and in those with a duration of ASP less than 30 months. Full article

(This article belongs to the Special Issue Antimicrobial Use and Stewardship during the COVID-19 Era)

11 pages, 305 KiB

Open AccessArticle

Antimicrobial Drug-Resistant Salmonella in Urban Cats: Is There an Actual Risk to Public Health?

by János Dégi, Kálmán Imre, Viorel Herman, Iulia Bucur, Isidora Radulov, Oana-Cătălina Petrec and Romeo Teodor Cristina

Antibiotics 2021, 10(11), 1404; https://doi.org/10.3390/antibiotics10111404 - 16 Nov 2021

Cited by 8 | Viewed by 2806

Abstract

The present study was undertaken to investigate the presence of Salmonella spp. in the faeces of client-owned cats in urban areas and to evaluate the risk that is posed to public health. Fresh faecal samples were collected directly from the rectums from 53 [...] Read more.

The present study was undertaken to investigate the presence of Salmonella spp. in the faeces of client-owned cats in urban areas and to evaluate the risk that is posed to public health. Fresh faecal samples were collected directly from the rectums from 53 diarrhoeic and 32 non-diarrhoeic cats. The samples were individually screened for the presence of Salmonella spp. using standard methods and, in the case of positive findings, the resulting typical colonies were then biochemically confirmed using the VITEK^®2 automated system. Subsequently, all of the Salmonella spp. isolates were molecularly tested for the presence of the invA gene. All of the isolates were serotyped using the slide agglutination technique according to the White–Kauffmann–Le Minor scheme. The phenotypic antimicrobial susceptibility profile of the isolated strains was obtained from the VITEK^®2 system using specific cards from the Gram-negative bacteria. A total of 16 of the samples (18.82%) tested positive for Salmonella spp. according to conventional and molecular testing methods. Serotyping of the Salmonella isolates showed the presence of three serotypes, namely S. enteritidis (n = 9; 56.3%), S. typhimurium (n = 4; 25%), and S. kentucky (n = 3; 18.8%). All of the tested strains showed strong resistance towards cefazolin, cefepime, ceftazidime, and ceftriaxone. Additionally, resistance (listed in descending order of strength) was observed to trimethoprim/sulfamethoxazole (11/16; 68.8%), ampicillin (10/16; 62.5%), ampicillin/sulbactam (9/16; 56.3%), gentamicin (9/16; 56.3%), nitrofurantoin (8/16; 50.0%), and amikacin (5/16; 31.3%). No resistance was expressed against ciprofloxacin, ertapenem, imipenem, levofloxacin, piperacillin/tazobactam, and tobramycin. The results of this study highlight a substantial public health issue and medical concern, especially in vulnerable people, such as children, the elderly, and immunocompromised individuals. Full article

(This article belongs to the Special Issue Antimicrobial Resistance and Treatment in Companion, Food and Exotic Animals)

9 pages, 544 KiB

Open AccessCommunication

First Global Report of Plasmid-Mediated mcr-1 and Extended-Spectrum Beta-Lactamase-Producing Escherichia coli from Sheep in Portugal

by Josman Dantas Palmeira, Marisa Haenni, Jean-Yves Madec and Helena Maria Neto Ferreira

Antibiotics 2021, 10(11), 1403; https://doi.org/10.3390/antibiotics10111403 - 16 Nov 2021

Cited by 7 | Viewed by 2380

Abstract

Resistances to extended-spectrum cephalosporins (ESC) and colistin are One Health issues since genes encoding these resistances can be transmitted between all sectors of the One Health concept, i.e., human, animal, and the environment. Among food-producing animals, sheep farming has long been overlooked. To [...] Read more.

Resistances to extended-spectrum cephalosporins (ESC) and colistin are One Health issues since genes encoding these resistances can be transmitted between all sectors of the One Health concept, i.e., human, animal, and the environment. Among food-producing animals, sheep farming has long been overlooked. To fill in this knowledge gap, we looked for ESC- and colistin resistance in 21 faecal samples collected from sheep in one farm in the south of Portugal. ESC-resistant isolates were selected on MacConkey agar plates supplemented with cefotaxime. Susceptibility testing was performed by the disk-diffusion method according to CLSI, while colistin MIC was determined by broth microdilution. ESC- and colistin-resistance genes were identified by PCR, and the clonality of all isolates was assessed by XbaI-PFGE. The replicon content was determined by PCR according to the PCR-based replicon typing (PBRT) scheme. Sixty-two non-duplicate ESC-resistant E. coli isolates were identified, which all presented an extended-spectrum beta-lactamase (ESBL) phenotype, mostly due to the presence of CTX-M genes. One CTX-M-1-producing E. coli was concomitantly colistin-resistant and presented the plasmid-mediated mcr-1 gene. Nearly all isolates showed associated resistances to non-beta-lactam antibiotics, which could act as co-selectors, even in the absence of beta-lactam use. The results showed a high proportion of ESBL-producing E. coli in sheep faeces. Their dissemination was very dynamic, with the spread of successful clones between animals, but also a large diversity of clones and plasmids, sometimes residing in the same animal. This study highlights the need for global surveillance in all food-producing sectors, in order to avoid the dissemination of genes conferring resistance to last-resort antibiotics in human medicine. Full article

(This article belongs to the Special Issue Antibiotic Resistance in Terrestrial and Aquatic Farmed Animals: An Urgent One Health Issue for Sustainability)

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12 pages, 276 KiB

Open AccessArticle

Epidemiology and Pattern of Resistance of Gram-Negative Bacteria Isolated from Blood Samples in Hospitalized Patients: A Single Center Retrospective Analysis from Southern Italy

by Paola Di Carlo, Nicola Serra, Sofia Lo Sauro, Vincenza Maria Carelli, Maurizio Giarratana, Juan Camilo Signorello, Alessandro Lucchesi, Giuseppe Manta, Maria Santa Napolitano, Teresa Rea, Antonio Cascio, Consolato Maria Sergi, Anna Giammanco and Teresa Fasciana

Antibiotics 2021, 10(11), 1402; https://doi.org/10.3390/antibiotics10111402 - 16 Nov 2021

Cited by 11 | Viewed by 2911

Abstract

Background: Blood culturing remains the mainstream tool to inform an appropriate treatment in hospital-acquired bloodstream infections and to diagnose any bacteremia. Methods: A retrospective investigation on the prevalence of Gram-negative bacteria (GNB) and their resistance in hospitalized patients by age, sex, and units [...] Read more.

Background: Blood culturing remains the mainstream tool to inform an appropriate treatment in hospital-acquired bloodstream infections and to diagnose any bacteremia. Methods: A retrospective investigation on the prevalence of Gram-negative bacteria (GNB) and their resistance in hospitalized patients by age, sex, and units from blood cultures (BCs) was conducted from January 2018 to April 2020 at Sant’Elia hospital, Caltanissetta, southern Italy. We divided the patient age range into four equal intervals. Results: Multivariate demographic and microbiological variables did not show an association between bacteria distributions and gender and age. The distribution by units showed a higher prevalence of Klebsiella pneumoniae and Acinetobacter baumannii in the intensive care unit (ICU) and Escherichia coli in the non-intensive care units (non-ICUs). The analysis of antibiotic resistance showed that E. coli was susceptible to a large class of antibiotics such as carbapenem and trimethoprim-sulfamethoxazole. K. pneumoniae showed a significant susceptibility to colistin, tigecycline, and trimethoprim-sulfamethoxazole. From the survival analysis, patients with E. coli had a higher survival rate. Conclusions: The authors stress the importance of the implementation of large community-level programs to prevent E. coli bacteremia. K. pneumoniae and E. coli susceptibility patterns to antibiotics, including in the prescription patterns of general practitioners, suggest that the local surveillance and implementation of educational programs remain essential measures to slow down the spread of resistance and, consequently, increase the antibiotic lifespan. Full article

(This article belongs to the Special Issue Spread of Multidrug-Resistant Microorganisms )

21 pages, 5208 KiB

Open AccessArticle

In Silico and In Vitro Evaluation of the Antimicrobial Potential of Bacillus cereus Isolated from Apis dorsata Gut against Neisseria gonorrhoeae

by Nurdjannah Jane Niode, Aryani Adji, Jimmy Rimbing, Max Tulung, Mohammed Alorabi, Ahmed M. El-Shehawi, Rinaldi Idroes, Ismail Celik, Fatimawali, Ahmad Akroman Adam, Kuldeep Dhama, Gomaa Mostafa-Hedeab, Amany Abdel-Rahman Mohamed, Trina Ekawati Tallei and Talha Bin Emran

Antibiotics 2021, 10(11), 1401; https://doi.org/10.3390/antibiotics10111401 - 15 Nov 2021

Cited by 15 | Viewed by 4278

Abstract

Antimicrobial resistance is a major public health and development concern on a global scale. The increasing resistance of the pathogenic bacteria Neisseria gonorrhoeae to antibiotics necessitates efforts to identify potential alternative antibiotics from nature, including insects, which are already recognized as a source [...] Read more.

Antimicrobial resistance is a major public health and development concern on a global scale. The increasing resistance of the pathogenic bacteria Neisseria gonorrhoeae to antibiotics necessitates efforts to identify potential alternative antibiotics from nature, including insects, which are already recognized as a source of natural antibiotics by the scientific community. This study aimed to determine the potential of components of gut-associated bacteria isolated from Apis dorsata, an Asian giant honeybee, as an antibacterial against N. gonorrhoeae by in vitro and in silico methods as an initial process in the stage of new drug discovery. The identified gut-associated bacteria of A. dorsata included Acinetobacter indicus and Bacillus cereus with 100% identity to referenced bacteria from GenBank. Cell-free culture supernatants (CFCS) of B. cereus had a very strong antibacterial activity against N. gonorrhoeae in an in vitro antibacterial testing. Meanwhile, molecular docking revealed that antimicrobial lipopeptides from B. cereus (surfactin, fengycin, and iturin A) had a comparable value of binding-free energy (BFE) with the target protein receptor for N. gonorrhoeae, namely penicillin-binding protein (PBP) 1 and PBP2 when compared with the ceftriaxone, cefixime, and doxycycline. The molecular dynamics simulation (MDS) study revealed that the surfactin remains stable at the active site of PBP2 despite the alteration of the H-bond and hydrophobic interactions. According to this finding, surfactin has the greatest antibacterial potential against PBP2 of N. gonorrhoeae. Full article

(This article belongs to the Topic Novel Antimicrobial Agents: Discovery, Design and New Therapeutic Strategies)

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Open AccessArticle

Effects of Metronidazole as an Adjunct to Non-Surgical Periodontal Therapy on Insulin Resistance in Type 2 Diabetics

by Ambrina Qureshi, Zeba Haque, Hina Qureshi and Waqas Ahmed Farooqui

Antibiotics 2021, 10(11), 1400; https://doi.org/10.3390/antibiotics10111400 - 15 Nov 2021

Cited by 1 | Viewed by 2612

Abstract

Treating periodontitis with metronidazole (MET) as an adjunct to scaling root planing (SRP) is suggested to have inconsistent effects on insulin resistance (IR) in type 2 diabetes mellitus (T2DM). This paper will present the effects of MET, in addition to SRP, on the [...] Read more.

Treating periodontitis with metronidazole (MET) as an adjunct to scaling root planing (SRP) is suggested to have inconsistent effects on insulin resistance (IR) in type 2 diabetes mellitus (T2DM). This paper will present the effects of MET, in addition to SRP, on the homeostatis model assessment of IR (HOMA-IR). A three-arm clinical trial was conducted and analyses were performed on T2DM participants with periodontitis (n = 74) who completed follow-up visits at 3 and 6 months after the intervention. The observed between-group and within-group mean changes in IR were found using ANOVA with repeated measures, followed by a post-hoc analysis, and a p-value of ≤0.05 was considered significant. Between-group analyses showed no difference in the HOMA-IR at 3 months, but at 6 months the difference was significant (p = 0.046). Within-group analyses showed that the HOMA-IR was significantly reduced in both test groups (p ≤ 0.05) over the period of time. Adjunct use of MET may result in a sudden short-term lowering of the HOMA-IR level within 3 months that may not be retained over 6 months when compared to the sustained lowering of the HOMA-IR levels in T2DM when intervened with SRP without MET. Full article

(This article belongs to the Special Issue Antibacterial Treatment in Periodontal and Endodontic Therapy)

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Antibiotics, Volume 10, Issue 11 (November 2021) – 155 articles

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