Evaluation of Biofilm Formation and Frequency of Multidrug-resistant and Extended Drug-resistant Strain in Pseudomonas aeruginosa Isolated from Burn Patients in Isfahan

Abstract Background Multidrug-resistant (MDR) and extensively drug-resistant (XDR) Pseudomonas aeruginosa (PA) have limited therapeutic options for treatment. Ceftolozane/tazobactam is a newer anti-pseudomonal drug effective against resistant PA infections, however resistance against this drug has now also developed and is increasing. In this study, we explored the combination of ceftolozane/tazobactam (CT) and meropenem (MP) as a possible effective regimen against MDR and XDR PA. Methods We obtained 33 non-duplicate isolates of MDR and XDR PA grown from blood, urine and respiratory samples collected from patients admitted between 2015 and 2019 at our two affiliate teaching hospitals. MDR PA was defined as resistance to 3 or more classes of anti-pseudomonal antibiotics, and XDR PA as resistance to all but two or less classes of anti-pseudomonal antibiotics. Antimicrobial preparations of both MP and CT were made according to manufacturer instructions. Susceptibility testing was performed using the checkerboard method in accordance to CLSI guidelines (CLSI M100, 2017). The ATCC 27853 strain of PA used as control. Synergy, additive effect, indifference and antagonism were defined as FIC (fractional inhibitory concentration) indices of ≤0.5, >0.5 to <1, >1 to <4, and >4, respectively. Results Thirteen (39%) of 33 PA isolates were classified as XDR, while 20 (61%) PA isolates were MDR. All isolates were resistant to MP (MIC50 >32 ug/mL), while only 2 (6%) isolates were susceptible to CT (MIC50 64 ug/mL). A synergistic effect was seen in 9 (27.3%) of PA isolates (FIC index range 0.28 to 0.5)— 2 of which were XDR PA, and 7 were MDR PA. An additive effect was seen in 12 (36.4%), with indifference seen in 12 (36.4%) of isolates. In this study, no antagonism was seen when CT and MP were combined. Conclusion When used in combination, CT and MP can exert a synergistic effect against MDR and XDR PA. Additive effect and indifference can also be seen when both antibiotics were used. Moreover, there was no antagonism seen when both antibiotics were combined. This study shows that the use of CT and MP in combination may be an option against XDR and MDR PA infections. Disclosures All Authors: No reported disclosures

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Draft Genome Sequence of a Clinically Isolated Extensively Drug-Resistant Pseudomonas aeruginosa Strain

Genome Announcements ◽

10.1128/genomea.00162-16 ◽

2016 ◽

Vol 4 (2) ◽

Author(s):

Bhavani Manivannan ◽

Niranjana Mahalingam ◽

Sudhir Jadhao ◽

Amrita Mishra ◽

Pravin Nilawe ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Antibiotic Resistance ◽

Genome Assembly ◽

Biofilm Formation ◽

Draft Genome ◽

Drug Resistant ◽

Draft Genome Assembly ◽

Extensively Drug Resistant ◽

History Of ◽

Urinary Tuberculosis

We present the draft genome assembly of an extensively drug-resistant (XDR) Pseudomonas aeruginosa strain isolated from a patient with a history of genito urinary tuberculosis. The draft genome is 7,022,546 bp with a G+C content of 65.48%. It carries 7 phage genomes, genes for quorum sensing, biofilm formation, virulence, and antibiotic resistance.

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Antimicrobial Activity of Ceftazidime-Avibactam Tested against Multidrug-Resistant Enterobacteriaceae and Pseudomonas aeruginosa Isolates from U.S. Medical Centers, 2013 to 2016

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01045-17 ◽

2017 ◽

Vol 61 (11) ◽

Cited By ~ 52

Author(s):

Helio S. Sader ◽

Mariana Castanheira ◽

Dee Shortridge ◽

Rodrigo E. Mendes ◽

Robert K. Flamm

Keyword(s):

Pseudomonas Aeruginosa ◽

Multidrug Resistant ◽

Drug Resistant ◽

Large Collection ◽

Content Type ◽

Negative Results ◽

Medical Centers ◽

Extensively Drug Resistant ◽

Genes Encoding

ABSTRACT The in vitro activity of ceftazidime-avibactam and many comparator agents was determined against various resistant subsets of organisms selected among 36,380 Enterobacteriaceae and 7,868 Pseudomonas aeruginosa isolates. The isolates were consecutively collected from 94 U.S. hospitals, and all isolates were tested for susceptibility by reference broth microdilution methods in a central monitoring laboratory (JMI Laboratories). Enterobacteriaceae isolates resistant to carbapenems (CRE) and/or ceftazidime-avibactam (MIC ≥ 16 μg/ml) were evaluated for the presence of genes encoding extended-spectrum β-lactamases and carbapenemases. Ceftazidime-avibactam inhibited >99.9% of all Enterobacteriaceae at the susceptible breakpoint of ≤8 μg/ml and was active against multidrug-resistant (MDR; n = 2,953; MIC50/90, 0.25/1 μg/ml; 99.2% susceptible), extensively drug-resistant (XDR; n = 448; MIC50/90, 0.5/2 μg/ml; 97.8% susceptible), and CRE (n = 513; MIC50/90, 0.5/2 μg/ml; 97.5% susceptible) isolates. Only 82.2% of MDR Enterobacteriaceae (n = 2,953) and 64.2% of ceftriaxone-nonsusceptible Klebsiella pneumoniae (n = 1,063) isolates were meropenem susceptible. Among Enterobacter cloacae (22.2% ceftazidime nonsusceptible), 99.8% of the isolates, including 99.3% of the ceftazidime-nonsusceptible isolates, were ceftazidime-avibactam susceptible. Only 23 of 36,380 Enterobacteriaceae (0.06%) isolates were ceftazidime-avibactam nonsusceptible, including 9 metallo-β-lactamase producers and 2 KPC-producing strains with porin alteration; the remaining 12 strains showed negative results for all β-lactamases tested. Ceftazidime-avibactam showed potent activity against P. aeruginosa (MIC50/90, 2/4 μg/ml; 97.1% susceptible), including MDR (MIC50/90, 4/16 μg/ml; 86.5% susceptible) isolates, and inhibited 71.8% of isolates nonsusceptible to meropenem, piperacillin-tazobactam, and ceftazidime (n = 628). In summary, ceftazidime-avibactam demonstrated potent activity against a large collection (n = 44,248) of contemporary Gram-negative bacilli isolated from U.S. patients, including organisms resistant to most currently available agents, such as CRE and meropenem-nonsusceptible P. aeruginosa.

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Evaluation of ceftazidime/avibactam for serious infections due to multidrug-resistant and extensively drug-resistant Pseudomonas aeruginosa

Journal of Global Antimicrobial Resistance ◽

10.1016/j.jgar.2018.07.010 ◽

2018 ◽

Vol 15 ◽

pp. 136-139 ◽

Cited By ~ 14

Author(s):

Olga Rodríguez-Núñez ◽

Marco Ripa ◽

Laura Morata ◽

Cristina de la Calle ◽

Celia Cardozo ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Multidrug Resistant ◽

Drug Resistant ◽

Extensively Drug Resistant ◽

Serious Infections

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Enhancement of pyocyanin production by subinhibitory concentration of royal jelly in Pseudomonas aeruginosa

F1000Research ◽

10.12688/f1000research.27915.3 ◽

2021 ◽

Vol 10 ◽

pp. 14

Author(s):

Dina Auliya Amly ◽

Puspita Hajardhini ◽

Alma Linggar Jonarta ◽

Heribertus Dedy Kusuma Yulianto ◽

Heni Susilowati

Keyword(s):

Pseudomonas Aeruginosa ◽

Bacterial Growth ◽

Biofilm Formation ◽

Royal Jelly ◽

Microtiter Plate ◽

Multidrug Resistant ◽

Clinical Isolates ◽

Antibiotic Tolerance ◽

Subinhibitory Concentration ◽

Pyocyanin Production

Background: Pseudomonas aeruginosa, a multidrug-resistant Gram-negative bacterium, produces pyocyanin, a virulence factor associated with antibiotic tolerance. High concentrations of royal jelly have an antibacterial effect, which may potentially overcome antibacterial resistance. However, in some cases, antibiotic tolerance can occur due to prolonged stress of low-dose antibacterial agents. This study aimed to investigate the effect of subinhibitory concentrations of royal jelly on bacterial growth, pyocyanin production, and biofilm formation of P. aeruginosa. Methods: Pseudomonas aeruginosa ATCC 10145 and clinical isolates were cultured in a royal jelly-containing medium to test the antibacterial activity. Pyocyanin production was observed by measuring the absorbance at 690 nm after 36 h culture and determined using extinction coefficient 4310 M-1 cm-1. Static microtiter plate biofilm assay performed to detect the biofilm formation, followed by scanning electron microscopy. Results: Royal jelly effectively inhibited the viability of both strains from a concentration of 25%. The highest production of pyocyanin was observed in the subinhibitory concentration group 6.25%, which gradually decreased along with the decrease of royal jelly concentration. Results of one-way ANOVA tests differed significantly in pyocyanin production of the two strains between the royal jelly groups. Tukey HSD test showed concentrations of 12.5%, 6.25%, and 3.125% significantly increased pyocyanin production of ATCC 10145, and the concentrations of 12.5% and 6.25% significantly increased production of the clinical isolates. Concentrations of 12.5% and 6.125% significantly induced biofilm formation of P. aeruginosa ATCC 10145, in line with the results of the SEM analysis. Conclusions: The royal jelly concentration of 25% or higher inhibits bacterial growth; however, the subinhibitory concentration increases pyocyanin production and biofilm formation in P. aeruginosa. It is advisable to determine the appropriate concentration of royal jelly to obtain beneficial virulence inhibiting activity.

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Biofilm Formation and Virulence Factors Among Pseudomonas aeruginosa Isolated From Burn Patients

Jundishapur Journal of Microbiology ◽

10.5812/jjm.22345 ◽

2015 ◽

Vol 8 (10) ◽

Cited By ~ 10

Author(s):

Zahra Ghanbarzadeh Corehtash ◽

Ahmad Khorshidi ◽

Farzaneh Firoozeh ◽

Hosein Akbari ◽

Azam Mahmoudi Aznaveh

Keyword(s):

Pseudomonas Aeruginosa ◽

Virulence Factors ◽

Biofilm Formation ◽

Burn Patients

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Susceptibility Profiles of Ceftolazane-Tazobactam (C-T) and Ceftazidime-Avibactam (CZA) Against Isolates of Multidrug-Resistant and Extensively Drug-Resistant Pseudomonas aeruginosa

Open Forum Infectious Diseases ◽

10.1093/ofid/ofw172.1364 ◽

2016 ◽

Vol 3 (suppl_1) ◽

Author(s):

Christopher Crist ◽

Richard Winn ◽

Kristen Fuhrmann ◽

Alanna Emrick

Keyword(s):

Pseudomonas Aeruginosa ◽

Multidrug Resistant ◽

Drug Resistant ◽

Extensively Drug Resistant ◽

Susceptibility Profiles

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Drug Resistance and Biofilm Production among Pseudomonas aeruginosa Clinical Isolates in a Tertiary Care Hospital of Nepal

Nepal Medical College Journal ◽

10.3126/nmcj.v21i2.25109 ◽

2019 ◽

Vol 21 (2) ◽

pp. 110-116

Author(s):

Rajani Shrestha ◽

N. Nayak ◽

D.R. Bhatta ◽

D. Hamal ◽

S.H. Subramanya ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Drug Resistance ◽

Biofilm Formation ◽

Tertiary Care ◽

Clinical Problem ◽

Multidrug Resistant ◽

Clinical Isolates ◽

Diffusion Method ◽

Care Hospital ◽

Microbiological Methods

Clinical isolates of Pseudomonas aeruginosa often exhibit multidrug resistance due to their inherent ability to form biofilms. Drug resistance in Ps. aeruginosa is a major clinical problem, especially in the management of patients with nosocomial infections and those admitted to ICUs with indwelling medical devices. To evaluate the biofilm forming abilities of the clinical isolates of Ps. aeruginosa and to correlate biofilm formation with antibiotic resistance. A total of 90 consecutive isolates of Ps. aeruginosa obtained from various specimens collected from patients visiting the Manipal Teaching Hospital, Pokhara, Nepal between January 2018 - October 2018 were studied. Isolates were identified by standard microbiological methods. Antibiotic susceptibility testing was performed by Kirby-Bauer disc diffusion method. All the isolates were tested for their biofilm forming abilities by employing the tissue culture plate assay. Of the 90 Ps. aeruginosa isolates, maximum i.e 42 (46.6%) were from patients in the age group of > 50 years. Majority (30; 33.3%) of the isolates were obtained from sputum samples. However, percentage isolation from other specimens like urine, endotracheal tube (ETT), pus, eye specimens and blood were 18.9%, 16.7%, 16.7%, 7.8% and 6.7% respectively. All the isolates were sensitive to polymixin B and colistin, 91.1% of the organisms were sensitive to imipenem, and more than 80% to aminoglycosides (80% to gentamicin, 83.3% to amikacin). A total of 29 (32.2%) organisms were biofilm producers. Maximum numbers of biofilm producing strains were obtained from ETT (8 of 15; 53.3%), pus (8 of 15; 53.3%) and blood (2 of 6; 33.3%) i.e from all invasive sites. None of the isolates from noninvasive specimens such as conjunctival swabs were biofilm positive. Significantly higher numbers of biofilm producers (23 of 29; 79.3%) were found to be multidrug resistant as compared to non-biofilm (6 of 61; 9.8%) producers (p=0.000). Ps. aeruginosa colonization leading to biofilm formation in deep seated tissues and on indwelling devices is a therapeutic challenge as majority of the isolates would be recalcitrant to commonly used antipseudomonal drugs. Effective monitoring of drug resistance patterns in all Pseudomonas clinical isolates should be a prerequisite for successful patient management.

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