Drug-Resistance Patterns of Clinical Isolates of Pseudomonas aeruginosa with Reference to Their Lipopolysaccharide Compositions

Chemotherapy ◽  
1997 ◽  
Vol 43 (5) ◽  
pp. 323-331 ◽  
Author(s):  
Miyuki Hasegawa ◽  
Intetsu Kobayashi ◽  
Takeshi Saika ◽  
Minoru Nishida
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Drug Resistance ◽  
Clinical Isolates ◽  
Resistance Patterns

scholarly journals Prevalence of Virulence Genes and Drug Resistance Profiles of Pseudomonas aeruginosa Isolated From Clinical Specimens

2021 ◽  
Vol 14 (8) ◽  
Author(s):  
Seyed Ali Bazghandi ◽  
Mohsen Arzanlou ◽  
Hadi Peeridogaheh ◽  
Hamid Vaez ◽  
Amirhossein Sahebkar ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Drug Resistance ◽  
Antibiotic Resistance ◽  
Virulence Genes ◽  
Virulence Gene ◽  
Clinical Isolates ◽  
Diffusion Method ◽  
Disk Diffusion Method ◽  
Clinical Specimens ◽  
Resistance Rates

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.

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

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.

scholarly journals Analysis of Clinical Factors, Bacterial Genotyping, and Drug Resistance for Spinal Tuberculosis in South-Central China

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Zheng Liu ◽  
Weiwei Li ◽  
Yilu Zhang ◽  
Yunqi Wu ◽  
Xiao Xiao ◽  
...  
Keyword(s):  
Drug Resistance ◽  
Clinical Features ◽  
Spinal Tuberculosis ◽  
Culture Method ◽  
Resistance Rate ◽  
Central China ◽  
Clinical Isolates ◽  
Chain Reactions ◽  
South Central ◽  
Resistance Patterns

Spinal tuberculosis (STB), which is the most frequent and serious form of skeletal TB, is seriously harmful to a patient’s life. However, very little research has been conducted on clinical isolates of STB. The purpose of this study was to genotype clinical isolates of Mycobacterium tuberculosis (MTB) from patients with STB, investigate their drug resistance profiles, and determine whether the genotypes and drug resistance patterns share any relationships with the demographic and clinical features of the patients. Preliminary species identification of the MTB strains was performed using a TCH/PNB culture method and multilocus polymerase chain reactions. Of the specimens collected from 85 hospital in-patients with STB at Xiangya Hospital, China, the 56 culture-positive MTB strains we identified were genotyped by spoligotyping. The strains were tested for resistance to anti-tuberculosis drugs (ATDs), and the demographic and clinical features of the patients were analyzed in combination with the genotyping and drug resistance results. Of the 56, cases, 53 involved M. tuberculosis and 3 involved M. bovis. Spoligotyping revealed 27 Beijing-type cases and 29 nonBeijing cases. When patients with STB were relapsing or experiencing systemic toxicity signs/symptoms (STS), the Beijing MTB-type strains predominated (p<0.05), but when the patients were receiving initial treatment or lacked STS, the nonBeijing type MTB strains dominated. The Beijing and nonBeijing types differed in their resistance patterns to 8 ATDs, and the resistance rate of the Beijing type was higher than that of the nonBeijing type (p<0.05). The bacteriological features of STB, including genotype and drug resistance, shared close relationships with the clinical features of patients with STB. Our data provide a reference for the diagnosis and treatment of STB.

scholarly journals Clinical Strains of Pseudomonas aeruginosa Overproducing MexAB-OprM and MexXY Efflux Pumps Simultaneously

2004 ◽  
Vol 48 (5) ◽  
pp. 1797-1802 ◽  
Author(s):  
Catherine Llanes ◽  
Didier Hocquet ◽  
Christelle Vogne ◽  
Dounia Benali-Baitich ◽  
Catherine Neuwirth ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Drug Resistance ◽  
Double Mutant ◽  
Efflux Pumps ◽  
Clinical Isolates ◽  
Clear Correlation ◽  
Sequencing Analysis ◽  
Repressor Gene ◽  
Reverse Transcription Pcr ◽  
Dna Sequencing Analysis

ABSTRACT Simultaneous overexpression of the MexAB-OprM and MexXY efflux systems was demonstrated by real-time reverse transcription-PCR and immunoblotting experiments for 12 multiresistant clinical isolates of Pseudomonas aeruginosa. DNA sequencing analysis showed that nine of these strains (named agrZ mutants) harbored mutations in mexZ, the product of which downregulates the expression of the mexXY operon. In addition, 8 of the 12 strains exhibited mutations in genes known to control transcription of the mexAB-oprM operon. Four of them were nalB mutants with alterations in the repressor gene mexR, three of them appeared to be nalC mutants deficient in gene PA3721 and overexpressing gene PA3720, and one strain was a nalB nalC double mutant. For MexAB-OprM as well as for MexXY, no clear correlation could be established between (i) the types of mutations, (ii) the expression level of mexA or mexX, and (iii) resistance to effluxed antibiotics. Finally, three isolates, named agrW mutants, overproduced MexXY and had an intact mexZ gene, and four strains overproduced MexAB-OprM and had intact mexR and PA3721 genes (nalD mutants). These data show that clinical isolates are able to broaden their drug resistance profiles by coexpressing two Mex efflux pumps and suggest the existence of additional regulators for MexAB-OprM and MexXY.

Sign in / Sign up

Export Citation Format

Share Document