Antimicrobial activities of silver dressings: an in vitro comparison

A range of silver-coated or -impregnated dressings are now commercially available for use but comparative data on their antimicrobial efficacies are limited. The antibacterial activities of five commercially available silver-coated/impregnated dressings were compared against nine common burn-wound pathogens, namely methicillin-sensitive and -resistant Staphylococcus aureus (MRSA), Enterococcus faecalis, Pseudomonas aeruginosa, Escherichia coli, Enterobacter cloacae, Proteus vulgaris, Acinetobacter baumannii and a multi-drug-efflux-positive Acinetobacter baumannii (BM4454), using a broth culture method. The rapidity and extent of killing of these pathogens under in vitro conditions were evaluated. All five silver-impregnated dressings investigated exerted bactericidal activity, particularly against Gram-negative bacteria, including Enterobacter species, Proteus species and E. coli. The spectrum and rapidity of action, however, ranged widely for different dressings. Acticoat and Contreet had a broad spectrum of bactericidal activities against both Gram-positive and -negative bacteria. Contreet was characterized by a very rapid bactericidal action and achieved a reduction of ⩾10 000 c.f.u. ml−1 in the first 30 min for Enterobacter cloacae, Proteus vulgaris, Pseudomonas aeruginosa and Acinetobacter baumanii. Other dressings demonstrated a narrower range of bactericidal activities. Understanding the characteristics of these dressings may enable them to be targeted more appropriately according to the specific requirements for use of a particular dressing, as in for prophylaxis in skin grafting or for an infected wound with MRSA.

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Profil Penggunaan Antibiotik dan Peta Kuman pada Pasien Gangren Diabetes Melitus di Sebuah RSUD di Kabupaten Gresik

Media Pharmaceutica Indonesiana (MPI) ◽

10.24123/mpi.v3i2.2966 ◽

2020 ◽

Vol 3 (2) ◽

pp. 96

Author(s):

Isna Romadhona ◽

Fauna Herawati ◽

Rika Yulia

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Pseudomonas Aeruginosa ◽

Klebsiella Pneumoniae ◽

Acinetobacter Baumannii ◽

Proteus Mirabilis ◽

Enterobacter Aerogenes ◽

Enterobacter Cloacae ◽

Proteus Vulgaris ◽

Diabetes Melitus

Antibiotik merupakan obat yang digunakan untuk mengatasi dan mencegah infeksi bakteri. Penggunaan antibiotik yang tidak tepat dapat menimbulkan berbagai masalah, diantaranya pengobatan akan lebih mahal dan juga risiko terjadinya resistensi bakteri terhadap antibiotik. Penelitian ini bertujuan untuk mengetahui profil penggunaan antibiotik dan profil peta kuman pada pasien gangren diabetes melitus di sebuah RSUD di Kabupaten Gresik serta untuk mengetahui kesesuaian penggunaan antibiotik dengan mengacu pada Permenkes Republik Indonesia No. 2406/Menkes/PER/XII/2011. Data penggunaan antibiotik diperoleh dari catatan Rekam Medis pada periode Januari – November 2017. Data penggunaan antibiotik dihitung dengan menggunakan rumus DDD/100 pasien-hari rawat. Hasil perhitungan DDD/100 pasien-hari rawat menunjukkan hasil sebesar 470,11 DDD/100 pasien-hari rawat. Peta kuman pada pasien gangren, melaporkan adanya bakteri Enterobacter cloacae 24%, Escherichia coli 18%, Staphylococcus aureus 15%, Acinetobacter baumannii 9%, Pseudomonas aeruginosa 6%, Citrobacter youngae 6%, Enterobacter aerogenes 6%, Proteus vulgaris 6%, Staphylococcus schleiferi 6%, Klebsiella pneumoniae 3%, dan Proteus mirabilis 3% . Penggunaan antibiotik seftriakson dan metronidazol pada pasien gangren diabetes melitus di sebuah RSUD di Kabupaten Gresik pada periode Januari – November 2017 telah sesuai dengan pedoman penggunaan antibiotik berdasarkan Permenkes Republik Indonesia No. 2406/Menkes/PER/ XII/2011, yaitu antibiotik golongan sefalosporin generasi III yang lebih aktif terhadap Enterobacteriaceae dan antibiotik golongan nitroimidazol yang dapat mengobati infeksi bakteri basil anerob Gram-Negatif.

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Activity of cefiderocol against high-risk clones of multidrug-resistant Enterobacterales, Acinetobacter baumannii, Pseudomonas aeruginosa and Stenotrophomonas maltophilia

Journal of Antimicrobial Chemotherapy ◽

10.1093/jac/dkaa117 ◽

2020 ◽

Vol 75 (7) ◽

pp. 1840-1849 ◽

Cited By ~ 8

Author(s):

Mercedes Delgado-Valverde ◽

M del Carmen Conejo ◽

Lara Serrano ◽

Felipe Fernández-Cuenca ◽

Álvaro Pascual

Keyword(s):

Pseudomonas Aeruginosa ◽

Acinetobacter Baumannii ◽

Stenotrophomonas Maltophilia ◽

Enterobacter Cloacae ◽

Multidrug Resistant ◽

In Vitro Activity ◽

Carbapenem Resistant ◽

Excellent Activity ◽

In Vitro Antibacterial Activity

Abstract Background Cefiderocol is a novel siderophore cephalosporin, developed for activity against MDR Gram-negative bacilli (MDR-GNB). Objectives To assess the in vitro antibacterial activity of cefiderocol against a collection of MDR-GNB clinical isolates from hospitals in southern Spain. Methods Two hundred and thirty-one isolates of successful clones were tested: 125 Enterobacterales (121 ESBL- and/or carbapenemase-producing Klebsiella pneumoniae and 4 carbapenemase-producing Enterobacter cloacae), 80 Acinetobacter baumannii, 6 Pseudomonas aeruginosa and 20 Stenotrophomonas maltophilia. Ceftolozane/tazobactam, ceftazidime, ceftazidime/avibactam, cefepime, aztreonam, meropenem, amikacin, ciprofloxacin, colistin and tigecycline were used as comparators against Enterobacterales, P. aeruginosa and A. baumannii. Minocycline, levofloxacin and trimethoprim/sulfamethoxazole were studied against S. maltophilia instead of aztreonam, ciprofloxacin and cefepime. MICs were determined by broth microdilution according to CLSI guidelines. MIC determination was performed in CAMHB for all antimicrobials except cefiderocol, where iron-depleted CAMHB was used. Results Cefiderocol showed potent in vitro activity against the isolates analysed. MIC50 and MIC90 values were in the ranges 0.125–8 mg/L and 0.5–8 mg/L, respectively, and 98% of isolates were inhibited at ≤4 mg/L. Only five isolates showed cefiderocol MICs of >4 mg/L: three ST2/OXA-24/40-producing A. baumannii, one ST114/VIM-1-producing E. cloacae and one ST114/VIM-1 + OXA-48-producing E. cloacae. All KPC-3-producing K. pneumoniae were susceptible to cefiderocol, even those resistant to ceftazidime/avibactam. P. aeruginosa isolates showed cefiderocol MICs of <4 mg/L, including those resistant to ceftolozane/tazobactam. S. maltophilia isolates displayed cefiderocol MICs of <4 mg/L, including those resistant to levofloxacin and/or trimethoprim/sulfamethoxazole. Conclusions Cefiderocol showed excellent activity against MDR-GNB, including carbapenem-resistant isolates, and was the most active antimicrobial tested against this collection.

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Antimicrobial activity of essential oils extracted from leaves of native Moroccan plants against clinical bacterial isolates

The International Arabic Journal of Antimicrobial Agents ◽

10.3823/819 ◽

2018 ◽

Vol 8 (1) ◽

Author(s):

Fatima El Malki ◽

Kamal Eddaraji ◽

Rajae Alloudane ◽

Hassane Greche ◽

Haiat Essalmani ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Pseudomonas Aeruginosa ◽

Antimicrobial Activity ◽

Antibacterial Activity ◽

Essential Oils ◽

Bactericidal Effect ◽

Antimicrobial Activities ◽

Acinetobacter Baumanii ◽

And Staphylococcus Aureus

Introduction: Medicinal plants are plentiful of bioactive molecules effective against multi-resistance bacteria. The aims of this study were to assess the in vitro antimicrobial activities of essential oils extracted from three Moroccan aromatic plants. Methodology: Analysis of essential oils of Origanum compactum, Rosmarinus officinalis and Pelargonium asperum, collected from different localities in Morocco, were performed using a GC-MS spectrophotometry. Antibacterial activity was evaluated in vitro for five clinical multi-resistant isolates. Results: Origanum showed strong antibacterial activity against tested strains except Pseudomonas aeruginosa while Rosmarinum showed a bactericidal effect against Acinetobacter baumanii, Escherichia coli and Staphylococcus aureus. Pelargonium presented only slight growth inhibition of Staphylococcus aureus on solid medium, but provided bactericidal effect against Acinetobacter baumanii and Staphylococcus aureus. Interestingly, fractions F7 and F8 of Pelargonium which represented only 0.3% and 0.1% of the total mass were found bactericidal respectively against Klebsiella pneumoniae and Pseudomonas aeruginosa. Conclusions: Ours results showed that the antimicrobial activities were variables depending on the chemical composition of essential oils, the fraction used and the microorganism tested.Essential oils fractionation allows detection of bioactive substances, especially those owning antimicrobial activity, present in small quantities.

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In vitro synergistic activities of tobramycin and selected beta-lactams against 75 gram-negative clinical isolates.

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.41.11.2586 ◽

1997 ◽

Vol 41 (11) ◽

pp. 2586-2588 ◽

Cited By ~ 22

Author(s):

R C Owens ◽

M A Banevicius ◽

D P Nicolau ◽

C H Nightingale ◽

R Quintiliani

Keyword(s):

Pseudomonas Aeruginosa ◽

Enterobacter Cloacae ◽

Clinical Isolates ◽

Synergistic Activity ◽

Beta Lactam ◽

Beta Lactams ◽

Acinetobacter Baumanii ◽

Gram Negative ◽

Combination Regimens

The microdilution checkerboard technique was utilized to distinguish synergistic activity between tobramycin and four beta-lactams: piperacillin-tazobactam, ticarcillin-clavulanate, ceftazidime, and ceftriaxone. Beta-lactam-aminoglycoside combinations were tested against 75 clinical isolates of Pseudomonas aeruginosa, Acinetobacter baumanii, Citrobacterfreundii, Serratia marcescens, and Enterobacter cloacae. Despite in vitro susceptibilities, all isolates demonstrated either synergism or indifference; no antagonism was observed. Against pathogenic gram-negative nosocomial isolates, a greater percentage of synergy was consistently observed with combination regimens containing tobramycin and piperacillin-tazobactam or ticarcillin-clavulanate than with the cephalosporin-containing regimens.

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Iron/Heme Metabolism-Targeted Gallium(III) Nanoparticles Are Active against Extracellular and Intracellular Pseudomonas aeruginosa and Acinetobacter baumannii

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.02643-18 ◽

2019 ◽

Vol 63 (4) ◽

Cited By ~ 9

Author(s):

Seoung-ryoung Choi ◽

Bradley E. Britigan ◽

Prabagaran Narayanasamy

Keyword(s):

Pseudomonas Aeruginosa ◽

Acinetobacter Baumannii ◽

Iron Acquisition ◽

Antimicrobial Activities ◽

Antibiofilm Activity ◽

Content Type ◽

Gallium Concentration ◽

Iron Heme

ABSTRACT Iron/heme acquisition systems are critical for microorganisms to acquire iron from the human host, where iron sources are limited due to the nutritional immune system and insolubility of the ferric form of iron. Prior work has shown that a variety of gallium compounds can interfere with bacterial iron acquisition. This study explored the intra- and extracellular antimicrobial activities of gallium protoporphyrin (GaPP), gallium mesoporphyrin (GaMP), and nanoparticles encapsulating GaPP or GaMP against the Gram-negative pathogens Pseudomonas aeruginosa and Acinetobacter baumannii, including clinical isolates. All P. aeruginosa and A. baumannii isolates were susceptible to GaPP and GaMP, with MICs ranging from 0.5 to ∼32 μg/ml in iron-depleted medium. Significant intra- and extracellular growth inhibition was observed against P. aeruginosa cultured in macrophages at a gallium concentration of 3.3 μg/ml (5 μM) of all Ga(III) compounds, including nanoparticles. Nanoparticle formulations showed prolonged activity against both P. aeruginosa and A. baumannii in previously infected macrophages. When the macrophages were loaded with the nanoparticles 3 days prior to infection, there was a 5-fold decrease in growth of P. aeruginosa in the presence of single emulsion F127 copolymer nanoparticles encapsulating GaMP (eFGaMP). In addition, all Ga(III) porphyrins and nanoparticles showed significant intracellular and antibiofilm activity against both pathogens, with the nanoparticles exhibiting intracellular activity for 3 days. Ga nanoparticles also increased the survival rate of Caenorhabditis elegans nematodes infected by P. aeruginosa and A. baumannii. Our results demonstrate that Ga nanoparticles have prolonged in vitro and in vivo activities against both P. aeruginosa and A. baumannii, including disruption of their biofilms.

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In Vitro Double and Triple Bactericidal Activities of Doripenem, Polymyxin B, and Rifampin against Multidrug-Resistant Acinetobacter baumannii, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Escherichia coli

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01768-09 ◽

2010 ◽

Vol 54 (6) ◽

pp. 2732-2734 ◽

Cited By ~ 61

Author(s):

Carl Urban ◽

Noriel Mariano ◽

James J. Rahal

Keyword(s):

Escherichia Coli ◽

Pseudomonas Aeruginosa ◽

Klebsiella Pneumoniae ◽

Acinetobacter Baumannii ◽

Carbapenem Resistance ◽

Polymyxin B ◽

Multidrug Resistant ◽

Carbapenem Resistant ◽

Bactericidal Activities

ABSTRACT In vitro double and triple bactericidal activities of doripenem, polymyxin B, and rifampin were assessed against 20 carbapenem-resistant clinical isolates with different mechanisms of carbapenem resistance. Bactericidal activity was achieved in 90% of all bacteria assayed using combinations of polymyxin B, doripenem, and rifampin against five each of the carbapenem-resistant Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Escherichia coli isolates studied. Combinations with these antibacterials may provide a strategy for treatment of patients infected with such organisms.

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Effect of Hypoxia on the Pathogenesis of Acinetobacter baumannii and Pseudomonas aeruginosa In Vitro and in Murine Experimental Models of Infection

Infection and Immunity ◽

10.1128/iai.00543-18 ◽

2018 ◽

Vol 86 (10) ◽

Cited By ~ 7

Author(s):

María Luisa Gil-Marqués ◽

María Eugenía Pachón-Ibáñez ◽

Jerónimo Pachón ◽

Younes Smani

Keyword(s):

Pseudomonas Aeruginosa ◽

Epithelial Cells ◽

Acinetobacter Baumannii ◽

Experimental Models ◽

Host Cells ◽

Content Type ◽

Bactericidal Activities ◽

Bacterial Concentrations

ABSTRACT Hypoxia modulates bacterial virulence and the inflammation response through hypoxia-inducible factor 1α (HIF-1α). Here we study the influence of hypoxia on Acinetobacter baumannii and Pseudomonas aeruginosa infections. In vitro, hypoxia increases the bactericidal activities of epithelial cells against A. baumannii and P. aeruginosa, reducing extracellular bacterial concentrations to 50.5% ± 7.5% and 90.8% ± 13.9%, respectively, at 2 h postinfection. The same phenomenon occurs in macrophages (67.6% ± 18.2% for A. baumannii at 2 h and 50.3% ± 10.9% for P. aeruginosa at 24 h). Hypoxia decreases the adherence of A. baumannii to epithelial cells (42.87% ± 8.16% at 2 h) and macrophages (52.0% ± 18.7% at 24 h), as well as that of P. aeruginosa (24.9% ± 4.5% in epithelial cells and 65.7% ± 5.5% in macrophages at 2 h). Moreover, hypoxia decreases the invasion of epithelial cells (48.6% ± 3.8%) and macrophages (8.7% ± 6.9%) by A. baumannii at 24 h postinfection and by P. aeruginosa at 2 h postinfection (75.0% ± 16.3% and 63.4% ± 5.4%, respectively). In vivo, hypoxia diminishes bacterial loads in fluids and tissues in animal models of infection by both pathogens. In contrast, mouse survival time was shorter under hypoxia (23.92 versus 36.42 h) with A. baumannii infection. No differences in the production of cytokines or HIF-1α were found between hypoxia and normoxia in vitro or in vivo. We conclude that hypoxia increases the bactericidal activities of host cells against both pathogens and reduces the interaction of pathogens with host cells. Moreover, hypoxia accelerates the rate at which animals die despite the lower bacterial concentrations in vivo.

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Антимікробна резистентність провідних збудників інфекцій сечових шляхів у Києві (Україна)

International Journal of Antibiotics and Probiotics ◽

10.31405/ijap.1-2.17.03 ◽

2017 ◽

Vol 1 (2) ◽

pp. 48-60

Author(s):

A.G. Salmanov ◽

A.V. Rudenko

Keyword(s):

Escherichia Coli ◽

Pseudomonas Aeruginosa ◽

Klebsiella Pneumoniae ◽

Staphylococcus Epidermidis ◽

Klebsiella Oxytoca ◽

Enterobacter Aerogenes ◽

Enterobacter Cloacae ◽

Proteus Vulgaris ◽

Providencia Rettgeri ◽

E Coli

Мета роботи — вивчити резистентність до антибіотиків бактеріальних збудників інфекцій сечових шляхів (ІСШ), виділених у пацієнтів урологічного стаціонару в м. Києві. Матеріали і методи. Досліджено 1612 штамів бактерій, виділених із сечі хворих з ІСШ (цистит, уретрит, пієлонефрит), госпіталізованих в урологічне відділення ДУ «Інститут урології НАМН України» у м. Києві протягом 2016 р. Серед пацієнтів переважали жінки — 1201 (74,5 %). Вік хворих становив від 17 до 74 років. Для збору даних використано медичну документацію лікарні. Мікробіологічні дослідження виконано у лабораторії мікробіології ДУ «Інститут урології НАМН України». Аналізували результати культурального дослідження зразків сечі, зібраних за наявності клінічних ознак ІСШ. Дослідження клінічного матеріалу та інтерпретацію отриманих результатів проводили загальноприйнятими методами. Вивчено чутливість уропатогенів до 31 антибіотика дискодифузійним методом відповідно до рекомендацій Інституту клінічних та лабораторних стандартів США (Clinical and Laboratory Standards Institute (CLSI)). Результати та обговорення. Аналіз мікробного спектра сечі виявив домінування серед уропатогенів штамів Escherichia coli (32,0 %), Enterococcus faecalis (19,5 %), Klebsiella pneumoniae (10,9 %), Staphylococcus epidermidis (8,9 %), S. haemolyticus (6,5 %) та Pseudomonas aeruginosa (6,4 %). Частка Enterococcus faecium, Enterobacter aerogenes і Streptococcus viridans становила відповідно 2,5, 2,2 і 1,6 %, Enterobacter cloacae, Klebsiella oxytoca, Acinetobacter baumannii, Proteus vulgaris та Providencia rettgeri — менше 1,0 %. У більшості випадків (69,7 %) мікроорганізми виділено у монокультурі, у решті випадків — у мікробних асоціа- ціях. Високу резистентність до тестованих антибіотиків виявили штами E. aerogenes (45,1 %), E. cloacae (45,7 %), E. faecium (40,9 %), E. faecalis (40,7 %), E. coli (39,9 %), P. aeruginosa (34,0 %), K. pneumoniae (28,6 %). Найбільш активними до уропатогенів були іміпенем (E. coli — 87,6 %, P. aeruginosa — 75,7 %, E. cloacae — 67,3 %, E. aerogenes — 72,6 %, K. pneumoniae — 93,2 %), меропенем (E. coli — 89,1 %, P. aeruginosa — 76,7 %, K. pneumoniae — 82,6 %), лефлоцин (E. coli — 74,5 %, ентерококи — 78,7 %, P. aeruginosa — 76,7 %, E. cloacae — 73,9 %, E. aerogenes — 80,4 %, K. pneumoniae — 83,5 %), амоксицилін/клавуланат (ентерококи — 84,6 %), фурагін (ентерококи — 82,6 %), цефоперазон (K. pneumoniae — 89,2 %, P. aeruginosa — 73,8 %), цефтріаксон (K. pneumoniae — 80,1 %). Висновки. Антибіотикорезистентність збудників ІСШ — важлива терапевтична проблема. Найбільшою активністю до уропатогенів характеризуються іміпенем, меропенем, лефлоцин, амоксицилін/ клавуланат, фурагін, цефоперазон, цефтріаксон, які можна розглядати як препарат вибору для призначення стартової терапії ІСШ. Необхідно здійснювати постійний моніторинг за резистентністю до дії антибіотиків. Політику використання антибіотиків у кожному стаціонарі слід визначати залежно від локальних даних щодо резистентності до протимікробних препаратів.

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