scholarly journals Comparison of virulence factors and antibiotic resistance of Pseudomonas aeruginosa strains isolated from patients with and without cystic fibrosis

2017 ◽  
Vol 25 (4) ◽  
pp. 327-334
Author(s):  
Salih Macin ◽  
Meral Akarca ◽  
Burcin Sener ◽  
Yakut Akyon

Abstract Its rising incidence, virulence factors and antibiotic resistance rate makes it difficult to treat Pseudomonas aeruginosa infections. The aim of this study was to compare virulence factors and antibiotic resistance of P. aeruginosa isolates from cystic fibrosis (CF) and other lower respiratory tract infections. Isolates from patients (n=125) were divided into two groups. The isolates in the first group were from CF patients (n=64). And in the other group isolates were from lower respiratory tract samples, from patients that did not have CF (n=61). The antibiotic susceptibility tests were done by using disc diffusion method. As phenotypic tests; DNase, protease, elastase, hemolysis, and motility test were performed. The mucoid form of P. aeruginosa was detected in 29.7% of CF patients’ isolates, whereas in the other group (non-CF) this rate was 9.8% (p=0.011). Motility in the CF patients’ isolates was lower (84.4%) then the other group (96.7%). The presence of DNase was significantly low in CF patients’ isolates when compared to the other group (p=0.009). When the antibiotic resistance was compared; ceftazidime, imipenem and meropenem and piperacillin resistance was found significantly low in CF patients compared to isolates from the other group (p≤0.05). Information about virulence factor patterns and antibiotic resistance of P. aeruginosa isolates from patients with cystic fibrosis and the patients without cystic fibrosis can prevent the unnecessary usage of antibiotics and lead the way to new approaches in treatment.

Author(s):  
X. Yang ◽  
Y. Lai ◽  
C. Li ◽  
J. Yang ◽  
M. Jia ◽  
...  

Abstract Lower respiratory tract infections (LRTIs) caused by Pseudomonas aeruginosa are the most common infection among hospitalized patients, associated with increased levels of morbidity, mortality and attributable health care costs. Increased resistant Pseudomonas worldwide has been quite meaningful to patients, especially in intensive care unit (ICUs). Different species of Pseudomonas exhibit different genetic profile and varied drug resistance. The present study determines the molecular epidemiology through DNA fingerprinting method and drug resistance of P. aeruginosa isolated from patients with LTRIs admitted in ICU. A total of 79 P. aeruginosa isolated from patients with LRTIs admitted in ICU were characterized by Restriction Fragment Length Polymorphism (RFLP), Random Amplified Polymorphic DNA (RAPD) and Repetitive Extrapalindromic PCR (REP-PCR). Antibiotic resistance was determined by minimum inhibitory concentration (MIC) assay while MDR genes, viz, blaTEM, blaOXA, blaVIM, blaCTX-M-15 were detected by polymerase chain reaction (PCR). Of the 137 Pseudomonas sp isolated from ICU patients, 57.7% of the isolates were reported to be P. aeruginosa. The overall prevalence of P. aeruginosa among the all included patients was 34.5%. The RAPD analysis yielded 45 different patterns with 72 clusters with 57% to 100% similarity level. The RFLP analysis yielded 8 different patterns with 14 clusters with 76% to 100% similarity level. The REP PCR analysis yielded 37 different patterns with 65 clusters with 56% to 100% similarity level. There was no correlation among the different DNA patterns observed between the three different methods. Predominant of the isolates (46.8%) were resistant to amikacin. Of the 79 isolates, 60.8% were positive for blaTEM gene and 39.2% were positive for blaOXA gene. P. aeruginosa was predominantly isolated from patients with LRTIs admitted in ICU. The difference in the similarity level observed between the three DNA fingerprinting methods indicates that there is high inter-strain variability. The high genetic variability and resistance patterns indicates that we should continuously monitor the trend in the prevalence and antibiotic resistance of P. aeruginosa especially in patients with LRTIs admitted in ICU.


2020 ◽  
Vol 4 (4) ◽  
pp. 186-191
Author(s):  
V.R. Makhmutova ◽  
◽  
T.E. Gembitskaya ◽  
A.G. Chermenskiy ◽  
O.N. Titova ◽  
...  

Background: in Russia, the life expectancy of cystic fibrosis (CF) patients increased by 10 years in 2011–2017 being 55.49 years in 2017. However, the number of patients with the chronic infection caused by non-fermenting gram-negative bacilli (NFGNB), e.g., Burkholderia cepacia, Achromobacter spp. etc., increased as well. Aim: to evaluate the differences in the nutritional and functional status and the severity of mutations in CF patients with chronic Pseudomonas infection or NFGNB infection and to assess the sensitivity of P. aeruginosa to tobramycin in CF patients in the Northwest region of Russia. Patients and Methods: 31 patients with CF aged 18–43 years (18 men and 13 women) were examined. The duration of the study was 12 months. Spirometry, anthropometry, and sputum culture were performed. Results: P. aeruginosa alone was isolated in 18 patients (58%), Achromobacter spp. in 9 patients (29%), and Burkholderia spp. in 4 patients (13%). The patients were divided into two groups, i.e., patients with chronic Pseudomonas infection (group 1, n=18, 10 out of 18 patients with mucoid strains of P. aeruginosa) or chronic NFGNB infection (group 2, n=13). The median age and the mode age were 27 years and 27 years, respectively, in group 1 and 24 years and 22 years, respectively, in group 2. It was demonstrated that CF patients with chronic NFGNB infection are characterized by poorer nutritional status (p<0.05) but similar functional status and the severity of CFTR gene mutation compared to CF patients with chronic Pseudomonas infection. It was also shown that Р. aeruginosa is highly sensitive to tobramycin (94.4%). Conclusions: in CF patients, chronic lower respiratory tract infections with Burkholderia cepacia and Achromobacter spp. account for 41.9% of gram-negative rod infections. Further studies and drug sensitivity monitoring are needed. KEYWORDS: cystic fibrosis, DNA test, chronic infection with Pseudomonas aeruginosa, Burkholderia cepacia, Achromobacter spp, non-fermenting gram-negative bacilli, CFTR mutation, nutritional status, pulmonary function tests, inhaled antibiotic therapy. FOR CITATION: Makhmutova V.R., Gembitskaya T.E., Chermenskiy A.G. et al. Comparative characteristics and clinical presentation of cystic fibrosis in adults with chronic lower respiratory tract infections with Pseudomonas aeruginosa and other non-fermenting gram-negative bacilli. Russian Medical Inquiry. 2020;4(4):186–191. DOI: 10.32364/2587-6821-2020-4-4-186-191.


Medicina ◽  
2008 ◽  
Vol 45 (1) ◽  
pp. 1
Author(s):  
Asta Dambrauskienė ◽  
Dalia Adukauskienė ◽  
Jolanta Jeroch ◽  
Astra Vitkauskienė

Aim of the study. To determine the associations between the source of infection and antibiotic resistance in patients with Pseudomonas aeruginosa bacteremia. Material and methods. A retrospective analysis of 50 patients with Pseudomonas aeruginosa bacteremia was carried out. If sepsis was suspected, blood culture was incubated in an automatic system BACTEC 9240. Then bacteria were identified, and their antibiotic resistance was estimated by disc diffusion method. If Pseudomonas aeruginosa strains were resistant to three or more antibiotics, they were considered as multidrug-resistant.Results. The origin of bacteremia was confirmed in 33 (66%) patients. Lower respiratory tract was the predominant source of Pseudomonas aeruginosa bacteremia (81.8%, n=27) as compared with infection of wound (39.4%, n=13), urinary tract (15.2%, n=5), and drain or cerebrospinal fluid (9.1%, n=3) (P<0.05). Eighteen percent (n=9) of strains, which caused bacteremia, were resistant to ceftazidime; 38% (n=19), to piperacillin; 22% (n=11), to imipenem; 26% (n=13), to meropenem; 24% (n=12), to ciprofloxacin; 40% (n=20), to gentamicin; and only 8% (n=4), to amikacin. Multidrug-resistant Pseudomonas aeruginosa strains were more frequently isolated if a source of infection was wound comparing to a source of other localization (61.5%, n=8 and 20.0%, n=4, respectively; P<0.05). Resistance of Pseudomonas aeruginosa strains to imipenem was associated with resistance to ciprofloxacin (13.2%, n=5 and 50.0%, n=6, retrospectively; P<0.05), but resistance to meropenem – both to ciprofloxacin and amikacin. Conclusions. The predominant source of Pseudomonas aeruginosa bacteremia was lower respiratory tract, and multidrug-resistant strains caused bacteremia more frequently if a source infection was wound. Pseudomonas aeruginosa resistance to carbapenems was associated with resistance to ciprofloxacin and resistance to meropenem – also to amikacin. Resistance of strains to ceftazidime and piperacillin was associated with resistance to gentamicin.


2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Shamshul Ansari ◽  
Rabindra Dhital ◽  
Sony Shrestha ◽  
Sangita Thapa ◽  
Ram Puri ◽  
...  

Introduction. Pseudomonas aeruginosais the most frequently isolated organism as it acts as the opportunistic pathogen and can cause infections in immunosuppressed patients. The production of different types of beta-lactamases renders this organism resistant to many commonly used antimicrobials. Therefore, the aim of this study was to document the antibiotic resistance rate inPseudomonas aeruginosaisolated from different clinical specimens.Methods. Pseudomonas aeruginosarecovered was identified by standard microbiological methods. Antibiotic susceptibility testing was performed by modified Kirby-Bauer disc diffusion method following Clinical and Laboratory Standard Institute (CLSI) guidelines and all the suspected isolates were tested for the production of ESBLs, MBLs, and AmpC.Results.Out of total (178) isolates, 83.1% were recovered from the inpatient department (IPD). Majority of the isolates mediated resistance towards the beta-lactam antibiotics, while nearly half of the isolates were resistant to ciprofloxacin. Most of the aminoglycosides used showed resistance rate up to 75% but amikacin proved to be better option. No resistance to polymyxin was observed. ESBLs, MBLs, and AmpC mediated resistance was seen in 33.1%, 30.9%, and 15.7% isolates, respectively.Conclusions. Antibiotic resistance rate and beta-lactamase mediated resistance were high. Thus, regular surveillance of drug resistance is of utmost importance.


2021 ◽  
Vol 10 (35) ◽  
pp. 2964-2968
Author(s):  
Swetha Thirumurthi ◽  
Priya Kanagamuthu ◽  
Rajasekaran Srinivasan ◽  
Bhalaji Dhanasekaran

BACKGROUND The term tracheostomy refers to forming an opening in the trachea.1,2 Its advantages include easy and direct access to lower respiratory tract, reduced risk of aspiration, faster weaning from ventilation support and improved physical and psychological comfort. But a common problem in tracheostomised patients is increased risk of colonisation of lower respiratory tract by exogenous bacteria because of direct exposure.1,3 This study was done to recognise pathogens in tracheal secretions collected from tracheostomised patients and their antibiotic sensitivity to treat them with appropriate antibiotics. METHODS This prospective study was done in 138 tracheostomised patients from October 2020 to March 2021 in intensive care unit (ICU) of Chettinad Hospital and Research Institute. Under sterile aseptic precautions, Day 0 and Day 7 cultures posttracheostomy was obtained and their antibiotic sensitivity was studied. Data was analysed using Statistical Package for Social Sciences (SPSS version 19) and presented in proportion, mean and standard deviation (Descriptive statistics). RESULTS In this study, of the 56 cases who had growth in their culture and sensitivity reports on day 0, the most common organism was Pseudomonas aeruginosa (33.9 %) sensitive to imipenem (94.7 %) followed by klebsiella (25 %) sensitive to teicoplanin, vancomycin, amikacin, cefoperazone/tazobactam, linezolid and piperacillin/tazobactam. On day 7, the growth of organisms isolated in tracheal culture got reduced from 56 cases to 16 cases. The prevalence of Pseudomonas reduced to 18.8 % in day 7 whereas Klebsiella pneumonia and Acinetobacter remained almost same from day 0 to day 7. CONCLUSIONS This study concludes the predominant pathogen as Pseudomonas aeruginosa with sensitivity to imipenem followed by Klebsiella with sensitivity to teicoplanin, vancomycin, amikacin, cefoperazone/tazobactam, linezolid and piperacillin/tazobactam on day 0 with reduction in the number of organisms on day 7 due to the fact that all our patients were admitted in ICU several days prior to tracheostomy and were started on antibiotics soon after admission as per choice of the treating physician. Hence, a clear understanding of bacterial colonisation post tracheostomy and its change in course is essential for timely intervention with empirical antibiotics for reducing the incidence of lower respiratory tract infections after tracheostomy in future. KEY WORDS Tracheostomy, Lower Respiratory Tract Infections, Pseudomonas Aeruginosa, Empirical Antibiotics.


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