Serotyping clinical isolates of Pseudomonas aeruginosa in relation to infection site antibiotic susceptibility and beta-lactamase production

1996 ◽  
Vol 7 (1) ◽  
pp. 65-68 ◽  
Author(s):  
M. Ravaoarinoro ◽  
S. Mohapatra ◽  
J. Shore ◽  
S. Rawal ◽  
A. Omri ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Antibiotic Susceptibility ◽  
Clinical Isolates ◽  
Beta Lactamase ◽  
Infection Site

scholarly journals Phenotypic and Molecular Detection of IMP and SPM Metallo-Beta-Lactamases in Clinical Isolates of Carbapenem Resistant Pseudomonas aeruginosa

2020 ◽  
Author(s):  
Zahra Norouzi Bazgir ◽  
Mohammad Ahanjan ◽  
Hamid Reza Goli ◽  
Roya Ghasemian ◽  
Mohammad Bagher Hashemi-Soteh
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Antibiotic Susceptibility ◽  
Molecular Detection ◽  
Clinical Isolates ◽  
Beta Lactamase ◽  
Antibiotic Susceptibility Pattern ◽  
Beta Lactamases ◽  
Phenotypic Identification ◽  
Carbapenem Resistant ◽  
High Prevalence

Abstract Objectives: Metallo-beta-lactamases play a major role in the resistance of Pseudomonas aeruginosa to carbapenems. The aim of this study was the phenotypic and molecular detection of IMP and SPM carbapenemase genes in 100 carbapenem-resistant clinical isolates of P. aeruginosa. The isolates identified using standard microbiological tests, and their antibiotic susceptibility pattern determined by disk agar diffusion (Kirby Bauer) method. Phenotypic identification of Metallo-beta-lactamase-producing strains assessed by the combined disk test (CDT). Then, PCR was used to detect the presence of IMP and SPM genes.Results: The highest and lowest levels of antibiotic resistance were observed against gentamicin (40%) and piperacillin-tazobactam (13%), respectively. Besides, 40 isolates (40%) had the Multi-drug Resistant (MDR) phenotype, while 5 (12.5%) MDR isolates were resistant to all antibiotics tested. The results of the CDT showed that among 43 carbapenem non-susceptible clinical isolates of P. aeruginosa, 33 (76.74%) isolates were Metallo-beta-lactamase-producing strains. Also, the frequency of the IMP gene was determined to be 9%, while none of these isolates carried the SPM gene. Due to the high prevalence of carbapenem-resistant and MDR P. aeruginosa in this study, routine antibiotic susceptibility testing and phenotypic identification of carbapenemase production by this bacterium are necessary for proper selection of antibiotics.

scholarly journals Presence of different beta-lactamase classes among clinical isolates of Pseudomonas aeruginosa expressing AmpC beta-lactamase enzyme

2010 ◽  
Vol 4 (04) ◽  
pp. 239-242 ◽  
Author(s):  
Supriya Upadhyay ◽  
Malay Ranjan Sen ◽  
Amitabha Bhattacharjee
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Treatment Options ◽  
Clinical Isolates ◽  
Diffusion Method ◽  
Beta Lactamase ◽  
Beta Lactam ◽  
Disk Diffusion Method ◽  
Extended Spectrum Beta Lactamase ◽  
Extended Spectrum ◽  
Enzyme Detection

Introduction: Infections caused by Pseudomonas aeruginosa are difficult to treat as the majority of isolates exhibit varying degrees of beta-lactamase mediated resistance to most of the beta-lactam antibiotics. It is also not unusual to find a single isolate that expresses multiple β-lactamase enzymes, further complicating the treatment options. Thus the present study was designed to investigate the coexistence of different beta-lactamase enzymes in clinical isolates of P. aeruginosa. Methodology: A total of 202 clinical isolates of P. aeruginosa were tested for the presence of AmpC beta-lactamase, extended spectrum beta-lactamase (ESBL) and metallo beta-lactamase (MBL) enzyme. Detection of AmpC beta-lactamase was performed by disk antagonism test and a modified three-dimensional method, whereas detection of ESBL was done by the combined disk diffusion method per Clinical and Laboratory Standards Institute (CLSI) guidelines and MBL were detected by the Imipenem EDTA disk potentiation test. Results: A total of 120 (59.4%) isolates were confirmed to be positive for AmpC beta-lactamase. Among them, 14 strains (7%) were inducible AmpC producers. Co-production of AmpC along with extended spectrum beta-lactamase and metallo beta-lactamase was reported in 3.3% and 46.6% isolates respectively. Conclusion: The study emphasizes the high prevalence of multidrug resistant P. aeruginosa producing beta-lactamase enzymes of diverse mechanisms. Thus proper antibiotic policy and measures to restrict the indiscriminative use of cephalosporins and carbapenems should be taken to minimize the emergence of this multiple beta-lactamase producing pathogens.

scholarly journals Spread of VIM-2 metallo-beta-lactamase in Pseudomonas aeruginosa and Acinetobacter baumannii clinical isolates from Iaşi, Romania

2013 ◽  
Vol 21 (4) ◽  
Author(s):  
Ana Irina Mereuţă ◽  
Aida Corina Bădescu ◽  
Olivia Simona Dorneanu ◽  
Luminiţa Smaranda Iancu ◽  
Cristina Gabriela Tuchiluş
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Acinetobacter Baumannii ◽  
Clinical Isolates ◽  
Beta Lactamase

scholarly journals In Vitro Activity of the Ultra-Broad-Spectrum Beta-lactamase Inhibitor QPX7728 in Combination with Multiple Beta-Lactam Antibiotics against Pseudomonas aeruginosa

2021 ◽  
Author(s):  
Olga Lomovskaya ◽  
Debora Rubio-Aparicio ◽  
Kirk Nelson ◽  
Dongxu Sun ◽  
Ruslan Tsivkovski ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Resistance Mechanisms ◽  
Clinical Isolates ◽  
Beta Lactamase ◽  
In Vitro Activity ◽  
Beta Lactam ◽  
Beta Lactams ◽  
Beta Lactamases ◽  
Lactamase Inhibitor

QPX7728 is an ultra-broad-spectrum beta-lactamase inhibitor with potent inhibition of key serine and metallo beta-lactamases. QPX7728 enhances the potency of multiple beta-lactams in beta-lactamase producing Enterobacterales and Acinetobacter spp. In this study we evaluated the in vitro activity of QPX7728 (8 μg/ml) combined with multiple beta-lactams against clinical isolates of Pseudomonas aeruginosa with varying beta-lactam resistance mechanisms. Seven-hundred-ninety clinical isolates were included in this study; 500 isolates, termed a “representative panel”, were selected to be representative the MIC distribution of meropenem (MEM), ceftazidime-avibactam (CAZ-AVI), and ceftolozane-tazobactam (TOL-TAZ) resistance for clinical isolates according to 2017 SENTRY surveillance data (representative panel). An additional 290 selected isolates (“challenge panel”), that were either non-susceptible to MEM or were resistant to TOL-TAZ or CAZ-AVI were also tested; 61 strains carried metallo beta-lactamases (MBLs), 211 strains were defective in the carbapenem porin OprD and 185 strains had the MexAB-OprM efflux pump overproduced based on a phenotypic test. Against the representative panel, susceptibility for all QPX7728/beta-lactam combinations was >90%. For the challenge panel, QPX-ceftolozane (TOL) was the most active combination (78.6% susceptible) followed by equipotent QPX-piperacillin (PIP) and QPX-cefepime (FEP), restoring susceptibility in 70.3% of strains (CLSI breakpoints for the beta-lactam compound alone). For MBL-negative strains, QPX-TOL and QPX-FEP restored the MIC values to susceptibility rates in ∼90% and ∼80% of strains, respectively, vs 68-70% for QPX-MEM and QPX-PIP and 63-65% for TOL-TAZ and CAZ-AVI. For MBL-positive strains, QPX-PIP restored the MIC to susceptibility values for ∼70% of strains vs 2-40% for other combinations. Increased efflux and impaired OprD had varying effect on QPX7728 combination depending on the partner beta-lactam tested. QPX7728 enhanced the potency of multiple beta-lactams against P. aeruginosa, with varying results according to the beta-lactamase production and other intrinsic resistance mechanisms.

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