scholarly journals Detection of metalloβ-lactamase genes in heteroresistant Pseudomonas aeruginosa isolated from clinical isolates in Egypt

2021 ◽  
Vol 12 (2) ◽  
pp. 1127-1135
Author(s):  
Alaa El-Din M.S. Hosny ◽  
Ali A. Abdelrahman ◽  
Dalia M. Hamed ◽  
Samira Zakeer

The aim of the study is to isolate and characterize Pseudomonas aeruginosa  recovered from different clinical specimens and then study the susceptibility of the isolated strains to different antibiotics, screening for heteroresistant isolates and detecting the metalloβ-lactamase genes in these isolates. A total of two hundred and fifty clinical isolates were collected, from which one hundred forty five isolates revealed Pseudomonas aeruginosa. They were collected from different clinical specimens applied for bacteriological testing from hospitalized in-patients admitted to Kasr Al Aini Hospital and Al-Demerdash Hospital, Egypt, in the period from February 2016 to December 2017. Antibiotic susceptibility testing was done using ten antibiotics. The study covered the heteroresistance of P.aeruginosa  towards several classes of antibiotics to make the statistical analysis convenient and to overview the significance of this resistance. The minimum inhibitory concentration was detected for the heteroresistant P.aeruginosa  resistant isolates.  The polymerase chain reaction of the heteroresistant strains was performed to detect the metallo-β-lactamase genes SIM, IMP and SPM and then sequencing was done consequently. SIM, IMP and SPM metalloβ-lactam e genes were detected in the heteroresistant isolates. The isolates showed a high resistance pattern to ampicillin (98.62%) and a high sensitivity rate to imipenem (96.55%) and the IMP gene was the highly significant gene.

2021 ◽  
Vol 16 (1) ◽  
pp. 1-8
Author(s):  
Hosniyeh E. Ladadweh ◽  
Hiba H. Falana ◽  
Jannat M. Ma�ali ◽  
Pinar A. Aweis ◽  
Hanan N. Nofal ◽  
...  

2021 ◽  
Vol 14 (8) ◽  
Author(s):  
Seyed Ali Bazghandi ◽  
Mohsen Arzanlou ◽  
Hadi Peeridogaheh ◽  
Hamid Vaez ◽  
Amirhossein Sahebkar ◽  
...  

Background: Drug resistance and virulence genes are two key factors for the colonization of Pseudomonas aeruginosa in settings with high antibiotic pressure, such as hospitals, and the development of hospital-acquired infections. Objectives: The objective of this study was to investigate the prevalence of drug resistance and virulence gene profiles in clinical isolates of P. aeruginosa in Ardabil, Iran. Methods: A total of 84 P. aeruginosa isolates were collected from clinical specimens of Ardabil hospitals and confirmed using laboratory standard tests. The disk diffusion method was used for antibiotic susceptibility testing and polymerase chain reaction (PCR) for the identification of P. aeruginosa virulence genes. Results: The highest and the lowest antibiotic resistance rates of P. aeruginosa strains were against ticarcillin-clavulanate (94%) and doripenem (33.3%), respectively. In addition, the frequency of multidrug-resistant (MDR) P. aeruginosa was 55.9%. The prevalence of virulence factor genes was as follows: algD 84.5%, lasB 86.9%, plcH 86.9%, plcN 86.9%, exoU 56%, exoS 51.2%, toxA 81%, nan1 13.1%, and pilB 33.3%. A significant association was observed between resistance to some antibiotics and the prevalence of virulence genes in P. aeruginosa. Conclusions: Our results revealed a high prevalence of antibiotic resistance, especially MDR, and virulence-associated genes in clinical isolates of P. aeruginosa in Ardabil hospitals. Owing to the low resistance rates against doripenem, gentamicin, and tobramycin, these antibiotics are recommended for the treatment of infections caused by highly resistant and virulent P. aeruginosa strains.


Author(s):  
Fateme DAVARZANI ◽  
Navid SAIDI ◽  
Saeed BESHARATI ◽  
Horieh SADERI ◽  
Iraj RASOOLI ◽  
...  

Background: Pseudomonas aeruginosa is one of the most common opportunistic bacteria causing nosocomial infections, which has significant resistance to antimicrobial agents. This bacterium is a biofilm and alginate producer. Biofilm increases the bacterial resistance to antibiotics and the immune system. Therefore, the present study was conducted to investigate the biofilm formation, alginate production and antimicrobial resistance patterns in the clinical isolates of P. aeruginosa. Methods: One hundred isolates of P. aeruginosa were collected during the study period (from Dec 2017 to Jul 2018) from different clinical samples of the patients admitted to Milad and Pars Hospitals at Tehran, Iran. Isolates were identified and confirmed by phenotypic and genotypic methods. Antimicrobial susceptibility was specified by the disk diffusion method. Biofilm formation and alginate production were measured by microtiter plate and carbazole assay, respectively. Results: Sixteen isolates were resistant to all the 12 studied antibiotics. Moreover, 31 isolates were MultidrugResistant (MDR). The highest resistance rate was related to ofloxacin (36 isolates) and the least resistance was related to piperacillin-tazobactam (21 isolates). All the isolates could produce the biofilm and alginate. The number of isolates producing strong, medium and weak biofilms was equal to 34, 52, and 14, respectively. Alginate production was more than 400 μg/ml in 39 isolates, 250-400 μg/ml in 51 isolates and less than 250 μg/ml in 10 isolates. Conclusion: High prevalence of MDR, biofilm formation, and alginate production were observed among the clinical isolates of P. aeruginosa. The results also showed a significant relationship between the amount of alginate production and the level of biofilm formation.


2022 ◽  
Vol 13 (1) ◽  
pp. 88-92
Author(s):  
M Swapna ◽  
G Sumathi ◽  
M Anitha

Background: Pseudomonas aeruginosa is one of the most prevalent nosocomial pathogens that cause a life-threatening infection. One of the important characteristics of P. aeruginosa is biofilm formation which leads to antibiotic resistance. Aims and Objectives: The aim of the study was to study the antibiotic resistance pattern of P. aeruginosa isolates and correlation with their biofilm-production. Materials and Methods: A total of 87 P. aeruginosa isolates from different clinical specimens were processed and confirmed by conventional microbiological methods as per standard methodology. Antibiotic sensitivity testing was done for all isolates. Biofilm producing isolates were identified by the microtiter plate method (MTPM). Results: Of 87 P. aeruginosa isolates, majority were from pus 33 (38%), followed by urine 26 (30%), sputum 19 (22%), body fluids 7 (8%), and blood 2 (2%). Biofilm producing isolates showed more resistance in comparison to non-biofilm producers. The observed difference between biofilm formation for multidrug resistant and susceptible isolates was found to be statistically significant. Conclusion: MTPM method was an effective test for detection of biofilm formation and was also able to verify biofilm production by P. aeruginosa. This indicated a higher propensity among the clinical isolates of P. aeruginosa to form biofilm and revealed a positive correlation between biofilm formation and antibiotic resistance. This indicates the need for testing of even susceptible isolates for virulence factors such as biofilm production.


2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Leila Ahmadian ◽  
Zahra Norouzi Bazgir ◽  
Mohammad Ahanjan ◽  
Reza Valadan ◽  
Hamid Reza Goli

In recent years, the prevalence of resistance to aminoglycosides among clinical isolates of Pseudomonas aeruginosa is increasing. The aim of this study was to investigate the role of aminoglycoside-modifying enzymes (AMEs) in resistance to aminoglycosides in clinical isolates of P. aeruginosa. The clinical isolates were collected from different hospitals. Disk agar diffusion test was used to determine the antimicrobial resistance pattern of the clinical isolates, and the minimum inhibitory concentration of aminoglycosides was detected by microbroth dilution method. The PCR was performed for discovery of aminoglycoside-modifying enzyme-encoding genes. Among 100 screened isolates, 43 (43%) isolates were resistant to at least one tested aminoglycosides. However, 13 (13%) isolates were resistant to all tested aminoglycosides and 37 isolates were detected as multidrug resistant (MDR). The resistance rates of P. aeruginosa isolates against tested antibiotics were as follows: ciprofloxacin (41%), piperacillin-tazobactam (12%), cefepime (32%), piperacillin (26%), and imipenem (31%). However, according to the MIC method, 13%, 32%, 33%, and 37% of the isolates were resistant to amikacin, gentamicin, tobramycin, and netilmicin, respectively. The PCR results showed that AAC(6 ′ )-Ib was the most commonly (26/43, 60.4%) identified AME-encoding gene followed by AAC(6 ′ )-IIa (41.86%), APH(3 ′ )-IIb (34.8%), ANT(3 ″ )-Ia (18.6), ANT(2 ″ )-Ia (13.95%), and APH(3 ″ )-Ib (2.32%). However, APH(3 ′ )-Ib was not found in any of the studied isolates. The high prevalence of AME-encoding genes among aminoglycoside-resistant P. aeruginosa isolates in this area indicated the important role of AMEs in resistance to these antibiotics similar to most studies worldwide. Due to the transmission possibility of these genes between the Gram-negative bacteria, we need to control the prescription of aminoglycosides in hospitals.


1999 ◽  
Vol 5 (1) ◽  
pp. 61-70
Author(s):  
A. S. Mustafa

The ability of two-band and three-band multiplex polymerase chain reactions to detect and differentiate Mycobacterium tuberculosis complex from non-tuberculous mycobacteria was evaluated. The polymerase chain reactions differentiated between M. tuberculosis and non-tuberculous mycobacteria when standard strains and clinical isolates of mycobacteria were tested. The sensitivity of the two-band and three-band techniques to detect M. tuberculosis in clinical specimens, compared with smear and/or culture, was 88% and 75% respectively. Although both techniques showed 100% specificity, the superior sensitivity of the two-band technique suggests that it could be more useful in the diagnosis of tuberculosis and in differentiating M. tuberculosis complex from non-tuberculous mycobacteria


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