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Isolation and Identification of Waterborne Antibiotic-Resistant Bacteria and Molecular Characterization of their Antibiotic Resistance Genes
Published on: March 3, 2023
Antipseudomonal β-Lactams Resistance in Iran
Mohammad Mahdi Rabiei1, Keivan Asadi1, Shervin Shokouhi1,2
1Clinical Research Development Unit of Loghman Hakim Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Abstract:
Over the last years, the mortality rate of Pseudomonas aeruginosa, which is one of the major reasons for severe infections, has been significantly increasing. This bacterium is highly resistant to many antibiotics, especially carbapenems, thanks to its complicated mechanism by which it can acquire exogenous genes. The purpose of this research is to have a review of empirical studies surveying the P. aeruginosa resistance to beta-lactams in Iran in order to investigate the most reliable methods by which the incidence of P. aeruginosa infections can be decreased and controlled. We performed a systematic review of all articles published from 2008 until 2018. Studies which did not address P. aeruginosa resistance to beta-lactams were excluded from the analysis. Studies with less than 10 cases were also excluded. Studies with more than ten cases, which did not have repetitive information, were taken into account for the final selection; 133 out of 893 articles were chosen. The resistance rate of P. aeruginosa among the articles was as follows: more than 72% of studies revealed >50% level of resistance to cefepime, followed by aztreonam (53.2%), ceftazidime (61%), piperacillin/tazobactam (54.5%), meropenem (48.3%), and imipenem (42.4%). The selection of empiric antipseudomonal antibiotics is absolutely uncertain and hazardous, and the risk of clinical failure may be more among cephalosporins and piperacillin-tazobactam as well as aztreonam. The results of this study illustrate that the methods enabling clinics to identify the bacterium resistance pattern and its genetic basis and to have the opportunity of empiric therapies through access to updated local data of antimicrobial susceptibility pattern are the most effective methods. However, the widespread usage of these approaches undoubtedly needs reliable molecular and nucleic acid-based devices, which are both affordable and available.
Insights
Pseudomonas aeruginosa infections are increasing due to antibiotic resistance. Identifying resistance patterns with local data and molecular tools is crucial for effective treatment and control.
Area of Science:
- Microbiology
- Infectious Diseases
- Pharmacology
Background:
- Rising mortality rates associated with *Pseudomonas aeruginosa* infections.
- Significant antibiotic resistance, particularly to carbapenems, complicates treatment.
- Acquisition of exogenous genes contributes to the bacterium's resistance mechanisms.
Purpose of the Study:
- To review empirical studies on *P. aeruginosa* resistance to beta-lactams in Iran.
- To identify effective methods for decreasing and controlling *P. aeruginosa* infections.
- To assess the current landscape of antibiotic resistance in Iran.
Main Methods:
- Systematic review of articles published between 2008 and 2018.
- Inclusion criteria: studies on *P. aeruginosa* beta-lactam resistance with >10 cases.
- Exclusion criteria: studies not addressing beta-lactam resistance or with <10 cases.
Main Results:
- High resistance rates observed: cefepime (>72%), ceftazidime (61%), aztreonam (53.2%), piperacillin/tazobactam (54.5%), meropenem (48.3%), imipenem (42.4%).
- Empiric antibiotic selection is hazardous, with increased risk of clinical failure for cephalosporins, piperacillin/tazobactam, and aztreonam.
- Identification of resistance patterns and genetic basis is key for effective empiric therapy.
Conclusions:
- Access to updated local antimicrobial susceptibility data is vital for effective empiric therapies.
- Reliable, affordable, and available molecular and nucleic acid-based devices are needed for widespread implementation.
- Targeted strategies based on local resistance patterns are essential for controlling *P. aeruginosa* infections.

