scholarly journals Microbiological features of Pseudomonas aeruginosa in children with Cystic Fibrosis

2021 ◽  
Vol 26 (3) ◽  
pp. 131-138
Author(s):  
O.V. Ishchenko ◽  
D.O. Stepanskyi
Keyword(s):  
Cystic Fibrosis ◽  
Pseudomonas Aeruginosa ◽  
Antimicrobial Agents ◽  
Posterior Pharyngeal Wall ◽  
Biochemical Properties ◽  
Diffusion Method ◽  
Candida Spp ◽  
Disk Diffusion Method ◽  
Pharyngeal Wall ◽  
Main Research

The purpose of the study was to determine the frequency rate of Pseudomonas aeruginosa infection among children with cystic fibrosis (CF) in Dnipro region and to provide microbiological characteristics of the obtained isolates. The study was conducting from January 2019 to December 2020. Children with genetically confirmed CF diagnosis were enrolled. The main research method was bacteriological with identification of microorganisms by biochemical properties; antimicrobial susceptibility was determined by disk-diffusion method. Biological material: mucus from a deep smear from the posterior pharyngeal wall, sputum and tracheobronchial lavage waters. The Leeds criteria were used to define persons with chronic infection. The study involved 21 children. We collected 183 respiratory samples with 49 isolates of P. aeruginosa. The most important co-existing pathogens were Staphylococcus aureus, Aspergillus spp. and Candida spp. In our study, P. aeruginosa was associated with Aspergillus spp. (χ2=20.952; df=1; p˂0.001). Mucoid isolates were found in 24.49% of cases. P. aeruginosa showed variable sensitivity to different groups of antimicrobial agents, but the highest resistance was to penicillins. Mucoid P. aeruginosa was more resistant to penicillins (p˂0.001) and cephalosporins (p=0.036). Infection P. aeruginosa is frequent among children with CF; there were three children with chronic bronchopulmonary infection P. aeruginosa in Dnipro region in the end of 2020. The likelihood of Aspergillus spp. infection was higher in the case of current P. aeruginosa infection. P. aeruginosa showed variable susceptibility to different groups of antimicrobial agents, but mucoid isolates were more resistant.

scholarly journals MICROBIOLOGICAL FEATURES OF STAPHYLOCOCCUS AUREUS ISOLATED FROM RESPIRATORY TRACT OF CHILDREN WITH CYSTIC FIBROSIS

2021 ◽  
Vol 74 (9) ◽  
pp. 2094-2099
Author(s):  
Oksana Ishchenko ◽  
Iryna Koshova ◽  
Inna Borysova ◽  
Dmytro Stepanskyi
Keyword(s):  
Cystic Fibrosis ◽  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Prevalence Rate ◽  
Posterior Pharyngeal Wall ◽  
Diffusion Method ◽  
Disk Diffusion Method ◽  
Pharyngeal Wall ◽  
Small Colony Variants ◽  
Small Colony

The aim: To determine the prevalence rate of Staphylococcus aureus infection among children with Cystic Fibrosis in the Dnieper region, to provide microbiological characteristics of the isolates and to elevate their susceptibility to antimicrobials. Materials and methods: Sputum, tracheobronchial lavage waters and/ or deep smear from the posterior pharyngeal wall were taken from children with genetically confirmed Cystic Fibrosis. Bacteriological method was the main. The first screening for small colony variants of Staphylococcus aureus was carried out after 48 hours of incubation. The antimicrobials susceptibility testing was determined by disk-diffusion method according to the EUCAST 2019. Microsoft Office Excel 2010 was used for statistical data processing. Results: Twenty one children were enrolled in the survey. The culture of Staphylococcus spp. was obtained from all patients with 40.8% positive for Staphylococcus aureus. Small colony variants appeared with the prevalence rate 21.6% after 48 hours of incubation. The frequency of associations between Staphylococcus aureus with auxotroph phenotype with the presence of Pseudomonas aeruginosa was significantly higher than with wild-type group. The 3d-generation aminoglycosides, the 3d-generation fluoroquinolones, linezolid, rifampicin and tetracyclines showed the best antimicrobial activity, however, resistance to cefoxitin and gentamicin was significantly higher in auxotroph-modified group. Conclusions: Infection Staphylococcus aureus is common among children. The appearance of auxotrophs registered after treatment with aminoglycosides and/ or co-trimoxazole and co-infection Pseudomonas aeruginosa. Isolates of Staphylococcus aureus showed good chemotherapeutic sensitivity, but tendency in increasing resistance registered for auxotroph-modified phenotype.

scholarly journals Detection of the Antiseptic Resistance Gene among Pseudomonas aeruginosa Isolates

2021 ◽  
pp. 75-82
Author(s):  
اخلاص نعمة
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Antibiotic Susceptibility ◽  
Antimicrobial Agents ◽  
Opportunistic Pathogen ◽  
Susceptibility Test ◽  
Diffusion Method ◽  
Bacterial Isolates ◽  
Disk Diffusion Method ◽  
Antibiotic Susceptibility Test ◽  
Antibiotics Susceptibility

Pseudomonas aeruginosa is an opportunistic pathogen that causes a number of infections in immunocompromised patients. This organism appears to improve resistance  to many antimicrobial agents and a high percentage of clinical isolates of P. aeruginosa exhibit multidrug resistance (MDR) phenotype . The purpose of this study is to screen the antibiotic susceptibility patterns and the prevalence of qacE delta1 gene among bacterial isolates. Accordingly, 145 samples were collected from different clinical sources from patients who admitted to different hospitals in Baghdad city in a period ranged 23/8/2018-1/1/2019. The isolates were diagnosed as P. aeruginosa based on routine bacteriological methods and confirmed by a molecular method using 16SrRNA gene. The antibiotic  susceptibility test was performed to all identified isolates by Kirby-Bauer Disk Diffusion method using ten  types of antibiotics. The results of antibiotics susceptibility test revealed high levels of resistance toward Piperacillin (72.22%), Trimethoprim (68%), Ceftazidime (68%), Colistin (40.28%), and Levofloxacin (33.33%). And , the minimum inhibitory concentration (MIC) of Cetrimide was tested using different concentrations (2.048 to 0.004µg/100µl) and the results showed that MIC values ranged between 2.048 and 0.016) μg/100μL, and  the concentration of  0.256 μg/100μl was more frequent . Finally, the prevalence of qacE delta1 gene among bacterial isolates was detected in percentage  63.88% among bacterial isolates .

scholarly journals Investigation of Pathogenic Escherichia Coli from Diarrheic Calves in Selective Area of Bangladesh

2015 ◽  
Vol 13 (1) ◽  
pp. 45-51 ◽  
Author(s):  
AKMA Islam ◽  
M Rahman ◽  
A Nahar ◽  
A Khair ◽  
MM Alam
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Agents ◽  
Biochemical Properties ◽  
Molecular Techniques ◽  
Diffusion Method ◽  
Molecular Technique ◽  
Isolation And Identification ◽  
Disk Diffusion Method ◽  
E Coli ◽  
Diarrheic Calves

Molecular technique was used to investigate the prevalence of virulent diarrheic genes in pathogenic Escherichia coli and their antibiotic sensitivity patterns. A hundred samples from 100 different diarrheic calves from mid-north-western part of Bangladesh were screened for the presence of virulence factors associated with diarrhea. Following isolation and identification on the basis of cultural, morphological and biochemical properties, the presence of the virulence genes such as eaeA, bfpA, elt, est, stx1 and stx2 were examined using PCR. Antimicrobial susceptibility of 57 E. coli was determined by agar disk diffusion method for 8 antimicrobial agents. Out of 100 samples 57 (57%) were found to be positive for E. coli and their distribution rates according to their age, breed and sex were  66.7% ( 6 days old ), 85.7% (Sahiwal breed) and in  64.2 % (female calves) respectively. Among 57 E. coli isolates, only 16 isolates were analyzed for the detection of the said genes. Among them, only eaeA gene was detected in 2 E. coli isolates (12.5 %). Antibiotic resistance patterns revealed that Oxacillin, Rifampicin and Penicillin were  100% resistant followed by Erythromycin which was more than 80% resistant. In case of Amoxicillin and Tetracycline, about 59.65% and 61.40% were found to be resistant respectively whereas all 57 E. coli isolates showed moderately susceptible (30%) to Cefuroxime, a second generation Cephalosporin. Therefore, none of the eight antimicrobials studied can not be recommended as single best therapeutic agent for the treatment of neonatal calf diarrhea. In addition, this study indicated that diarrhea in calves in these locations can be ascribed to mainly Enteropathogenic E. coli (EPEC) which was atypical (only contained the eaeA genes but not bfpA). However, further studies are necessary to characterize the isolated eaeA gene positive E. coli by serotyping, tissue culture assay and other molecular techniques to find out the potentiality of those virulent genes contributing pathogenicity of E. coli causing diarrhea in calves.DOI: http://dx.doi.org/10.3329/bjvm.v13i1.23716Bangl. J. Vet. Med. (2015). 13 (1): 45-51

scholarly journals Comparison of Agar Diffusion Methodologies for Antimicrobial Susceptibility Testing of Pseudomonas aeruginosa Isolates from Cystic Fibrosis Patients

2000 ◽  
Vol 38 (5) ◽  
pp. 1818-1822 ◽  
Author(s):  
Jane L. Burns ◽  
Lisa Saiman ◽  
Susan Whittier ◽  
Davise Larone ◽  
Jay Krzewinski ◽  
...  
Keyword(s):  
Cystic Fibrosis ◽  
Pseudomonas Aeruginosa ◽  
Susceptibility Testing ◽  
Correlation Coefficients ◽  
Disk Diffusion ◽  
Diffusion Method ◽  
Broth Microdilution ◽  
Disk Diffusion Method ◽  
Agar Diffusion ◽  
Broth Microdilution Method

Pseudomonas aeruginosa is the most common pathogen infecting the lungs of patients with cystic fibrosis (CF). Improved antimicrobial chemotherapy has significantly increased the life expectancy of these patients. However, accurate susceptibility testing of P. aeruginosa isolates from CF sputum may be difficult because the organisms are often mucoid and slow growing. This study of 597 CF isolates of P. aeruginosa examined the correlation of disk diffusion and Etest (AB BIODISK, Solna, Sweden) results with a reference broth microdilution method. The rates of interpretive errors for 12 commonly used antipseudomonal antimicrobials were determined. The disk diffusion method correlated well (zone diameter versus MIC) for all of the agents tested. However, for mucoid isolates, correlation coefficients (r values) for piperacillin, piperacillin-tazobactam, and meropenem were <0.80. The Etest correlation with reference broth microdilution results (MIC versus MIC) was acceptable for all of the agents tested, for both mucoid and nonmucoid isolates. Category interpretation errors were similar for the disk diffusion and Etest methods with 0.4 and 0.1%, respectively, very major errors (false susceptibility) and 1.1 and 2.2% major errors (false resistance). Overall, both agar diffusion methods appear to be broadly acceptable for routine clinical use in susceptibility testing of CF isolates of P. aeruginosa.

scholarly journals Achromobacter xylosoxidans infection and resistance monitoring in adult cystic fibrosis patients

2021 ◽  
Vol 5 (7) ◽  
pp. 462-467
Author(s):  
V.R. Makhmutova ◽  
◽  
T.E. Gembitskaya ◽  
A.G. Chermensky ◽  
O.N. Titova ◽  
...  
Keyword(s):  
Cystic Fibrosis ◽  
Pseudomonas Aeruginosa ◽  
Burkholderia Cepacia ◽  
Fatal Outcome ◽  
Burkholderia Cepacia Complex ◽  
Diffusion Method ◽  
Achromobacter Xylosoxidans ◽  
Disk Diffusion Method ◽  
Resistance Monitoring

Aim: to evaluate the infection rate and resistance of isolated Achromobacter xylosoxidans to carbapenems in adult cystic fibrosis patients (CF). Patients and Methods: a retrospective analysis of the results of culture test and time-of-flight mass spectrometry MALDI-TOF was conducted: 685 sputum samples of 58 adult CF patients for a period of 5 years (2016–2020). To assess the sensitivity to imipenem and meropenem, the agar gradient diffusion and disk diffusion method were used. Results: the incidence of infection with A. xylosoxidans in adult CF patients for the period from 2016 to 2020 when monitoring a single sample of patients (n=24) to evaluate the occurrence of this pathogen with increasing age ranged from 16.6% in 2016–2017, increasing to 37.5% in 2018–2019, and with a further reduction to 20.8% (associated with disease fatal outcome in 3 of the 9 infected patients). There was no statistically significant dependence of the fatal outcome on infection with A. xylosoxidans. When analyzing the entire pool of patients (n=58) from 2016 to 2020, the release frequency of Pseudomonas aeruginosa remains approximately the same, varying from 63.3% to 46.5% and maintaining a numerical advantage in all follow-up periods, while the A. xylosoxidans infection ranges from 13.7% to 39.3%. In 2016–2018, 50% of isolates were sensitive to carbapenems, in 2018 — 53.8% of isolates, in 2019–2020 — the activity of obtained isolates decreased to 37.5% and 30.7%, respectively. Conclusion: despite the dynamics of indicators and the sample size, the dynamics over 5 years maintained a group-wide proportion of microbiome species dominated primarily by Pseudomonas infection and A. xylosoxidans. In our follow-up, the activity of carbapenems in relation to A. xylosoxidans has almost halved. KEYWORDS: cystic fibrosis, Burkholderia cepacia complex, Achromobacter xylosoxidans, Pseudomonas aeruginosa, lethality, antibiotic resistance, carbapenems. FOR CITATION: Makhmutova V.R., Gembitskaya T.E., Chermensky A.G. et al. Achromobacter xylosoxidans infection and resistance monitoring in adult cystic fibrosis patients. Russian Medical Inquiry. 2021;5(7):462–467 (in Russ.). DOI: 10.32364/2587-6821-2021-5-7-462-467.

scholarly journals Biological Effect of Posidonia oceanica Seaweed on Some Pathogenic Microbes

2020 ◽  
Vol 35 (4) ◽  
pp. 339-346
Author(s):  
Ahmed Amrajaa Abdulrraziq ◽  
Sami Mohammed Salih
Keyword(s):  
Escherichia Coli ◽  
Pseudomonas Aeruginosa ◽  
Pathogenic Bacteria ◽  
Posidonia Oceanica ◽  
Biologically Active ◽  
Diffusion Method ◽  
Leaf Extracts ◽  
Candida Spp ◽  
Disk Diffusion Method ◽  
Marine Diversity

Compared to other coasts, Libyan coasts are characterized by low levels of pollution. This makes them a suitable environment for marine diversity, especially seaweeds, which may be considered a source of new compounds that are biologically active in their resistance to microbes. Therefore, the present study was conducted with the aim of testing the bioactivity of leave and rhizome extracts of Posidonia oceanica seaweed (aqueous, ethanol, and acetone) at concentrations (50, 100, and 150) mg/ml against three types of pathogenic bacteria (Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa), and fungus (Candida spp.), by a sensitivity test in the form of a disk diffusion method. The results showed that Posidonia oceanica seaweed extracts have good inhibitory activity against S.aureus and Candida spp., and that the concentration of 150 mg/ml is the most effective for all extracts. The results also indicated that rhizome extracts are more efficient than leaf extracts, and the acetone extract is the best in inhibiting the tested microbes. Also, Escherichia coli and Pseudomonas aeruginosa are the most resistant to all extracts, regardless of type and concentration used.  

The technical aspects of collecting and transporting the sputum cystic fibrosis patients

2016 ◽  
Vol 7 (2) ◽  
pp. 92-95
Author(s):  
Aleksandr V Orlov ◽  
Viktor N Kovalev ◽  
Marina N Ignatieva ◽  
Lubov A Antipova ◽  
Ekaterina A Egorova ◽  
...  
Keyword(s):  
Cystic Fibrosis ◽  
Pseudomonas Aeruginosa ◽  
Burkholderia Cepacia ◽  
Posterior Pharyngeal Wall ◽  
Posterior Wall ◽  
Small Towns ◽  
Pharyngeal Wall ◽  
North West ◽  
Large Cities ◽  
The North

Timely diagnosis of infection in cystic fibrosis patients is a major aim. This is especially important for timely treatment in primary seed Ps. aeruginosa and Burkholderia cepacia. Early treatment allows in most cases to prevent the formation of chronic Pseudomonas aeruginosa infection. This also applies to re-sowing Ps. aeruginosa after the previous eradication. However, not all cities and small towns have laboratories equipped sufficiently to do bacteriological analysis of cystic fibrosis patients sputum, especially for the allocation of Ps. aeruginosa and Burkholderia cepacia. In this regard, the choice of methods of collecting material and its storage and transportation to specialized laboratories is very relevant. In 5 cities of the North-West region of Russia in 51 patients with cystic fibrosis conducted fences sputum and its subsequent delivery and carrying out of sowing in NIIDA FMBA of Russia in St Petersburg. Five patients extract sputum by coughing, 12 - induced sputum, 24 - were held flush with the posterior wall of the pharynx, 8 - swab from posterior pharyngeal wall, the parents of 2 patients brought the sputum coughed in previous day at house. As the result of bacteriologic test in 15 children certain pathogens were detected for the first time: Staphylococcus in 10 patients, Pseudomonas aeruginosa in 4 patients, Achromobacter in 1 person. Pathogens are well preserved during transportation of specimens to the laboratory in transport medium in the cold, which allows the use of bacteriological laboratories of large cities for carrying out sputum cultures of patients from other regions.

scholarly journals Pseudomonas aeruginosa PA14 Enhances the Efficacy of Norfloxacin against Staphylococcus aureus Newman Biofilms

2020 ◽  
Vol 202 (18) ◽  
Author(s):  
Giulia Orazi ◽  
Fabrice Jean-Pierre ◽  
George A. O’Toole
Keyword(s):  
Cystic Fibrosis ◽  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Antimicrobial Agents ◽  
Respiratory Infections ◽  
Multiple Infection ◽  
Bacterial Biofilms ◽  
Interspecies Interactions ◽  
Chronic Infections ◽  
Content Type

ABSTRACT The thick mucus within the airways of individuals with cystic fibrosis (CF) promotes frequent respiratory infections that are often polymicrobial. Pseudomonas aeruginosa and Staphylococcus aureus are two of the most prevalent pathogens that cause CF pulmonary infections, and both are among the most common etiologic agents of chronic wound infections. Furthermore, the ability of P. aeruginosa and S. aureus to form biofilms promotes the establishment of chronic infections that are often difficult to eradicate using antimicrobial agents. In this study, we found that multiple LasR-regulated exoproducts of P. aeruginosa, including 2-heptyl-4-hydroxyquinoline N-oxide (HQNO), siderophores, phenazines, and rhamnolipids, likely contribute to the ability of P. aeruginosa PA14 to shift S. aureus Newman norfloxacin susceptibility profiles. Here, we observe that exposure to P. aeruginosa exoproducts leads to an increase in intracellular norfloxacin accumulation by S. aureus. We previously showed that P. aeruginosa supernatant dissipates the S. aureus membrane potential, and furthermore, depletion of the S. aureus proton motive force recapitulates the effect of the P. aeruginosa PA14 supernatant on shifting norfloxacin sensitivity profiles of biofilm-grown S. aureus Newman. From these results, we hypothesize that exposure to P. aeruginosa PA14 exoproducts leads to increased uptake of the drug and/or an impaired ability of S. aureus Newman to efflux norfloxacin. Surprisingly, the effect observed here of P. aeruginosa PA14 exoproducts on S. aureus Newman susceptibility to norfloxacin seemed to be specific to these strains and this antibiotic. Our results illustrate that microbially derived products can alter the ability of antimicrobial agents to kill bacterial biofilms. IMPORTANCE Pseudomonas aeruginosa and Staphylococcus aureus are frequently coisolated from multiple infection sites, including the lungs of individuals with cystic fibrosis (CF) and nonhealing diabetic foot ulcers. Coinfection with P. aeruginosa and S. aureus has been shown to produce worse outcomes compared to infection with either organism alone. Furthermore, the ability of these pathogens to form biofilms enables them to cause persistent infection and withstand antimicrobial therapy. In this study, we found that P. aeruginosa-secreted products dramatically increase the ability of the antibiotic norfloxacin to kill S. aureus biofilms. Understanding how interspecies interactions alter the antibiotic susceptibility of bacterial biofilms may inform treatment decisions and inspire the development of new therapeutic strategies.

Activities of Tobramycin and Six Other Antibiotics against Pseudomonas aeruginosa Isolates from Patients with Cystic Fibrosis

1999 ◽  
Vol 43 (12) ◽  
pp. 2877-2880 ◽  
Author(s):  
Ribhi M. Shawar ◽  
David L. MacLeod ◽  
Richard L. Garber ◽  
Jane L. Burns ◽  
Jenny R. Stapp ◽  
...  
Keyword(s):  
Cystic Fibrosis ◽  
Pseudomonas Aeruginosa ◽  
Antimicrobial Agents ◽  
Active Drug ◽  
Resistance Mechanisms ◽  
Phase Iii ◽  
In Vitro Activity ◽  
Phase Iii Clinical Trials ◽  
Multiple Antibiotics

ABSTRACT The in vitro activity of tobramycin was compared with those of six other antimicrobial agents against 1,240 Pseudomonas aeruginosa isolates collected from 508 patients with cystic fibrosis during pretreatment visits as part of the phase III clinical trials of tobramycin solution for inhalation. The tobramycin MIC at which 50% of isolates are inhibited (MIC50) and MIC90 were 1 and 8 μg/ml, respectively. Tobramycin was the most active drug tested and also showed good activity against isolates resistant to multiple antibiotics. The isolates were less frequently resistant to tobramycin (5.4%) than to ceftazidime (11.1%), aztreonam (11.9%), amikacin (13.1%), ticarcillin (16.7%), gentamicin (19.3%), or ciprofloxacin (20.7%). For all antibiotics tested, nonmucoid isolates were more resistant than mucoid isolates. Of 56 isolates for which the tobramycin MIC was ≥16 μg/ml and that were investigated for resistance mechanisms, only 7 (12.5%) were shown to possess known aminoglycoside-modifying enzymes; the remaining were presumably resistant by an incompletely understood mechanism often referred to as “impermeability.”

scholarly journals Methicillin-resistant Staphylococcus aureus bloodstream infection: risk factors and clinical outcome in non-intensive-care units

2012 ◽  
Vol 45 (2) ◽  
pp. 189-193 ◽  
Author(s):  
Karinne Spirandelli Carvalho Naves ◽  
Natália Vaz da Trindade ◽  
Paulo Pinto Gontijo Filho
Keyword(s):  
Risk Factors ◽  
Staphylococcus Aureus ◽  
Bloodstream Infection ◽  
Antimicrobial Agents ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Methicillin Resistance ◽  
Diffusion Method ◽  
Disk Diffusion Method ◽  
Methicillin Resistant ◽  
Staphylococcus Aureus Bloodstream Infection

INTRODUCTION: Methicillin-resistant Staphylococcus aureus (MRSA) is spread out in hospitals across different regions of the world and is regarded as the major agent of nosocomial infections, causing infections such as skin and soft tissue pneumonia and sepsis. The aim of this study was to identify risk factors for methicillin-resistance in Staphylococcus aureus bloodstream infection (BSI) and the predictive factors for death. METHODS: A retrospective cohort of fifty-one patients presenting bacteraemia due to S. aureus between September 2006 and September 2008 was analysed. Staphylococcu aureus samples were obtained from blood cultures performed by clinical hospital microbiology laboratory from the Uberlândia Federal University. Methicillinresistance was determined by growth on oxacillin screen agar and antimicrobial susceptibility by means of the disk diffusion method. RESULTS: We found similar numbers of MRSA (56.8%) and methicillin-susceptible Staphylococcus aureus (MSSA) (43.2%) infections, and the overall hospital mortality ratio was 47%, predominantly in MRSA group (70.8% vs. 29.2%) (p=0.05). Age (p=0.02) was significantly higher in MRSA patients as also was the use of central venous catheter (p=0.02). The use of two or more antimicrobial agents (p=0.03) and the length of hospital stay prior to bacteraemia superior to seven days (p=0.006) were associated with mortality. High odds ratio value was observed in cardiopathy as comorbidity. CONCLUSIONS: Despite several risk factors associated with MRSA and MSSA infection, the use of two or more antimicrobial agents was the unique independent variable associated with mortality.

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