scholarly journals Antibiotic resistance, biofilm formation, and biofilm-associated genes among Stenotrophomonas maltophilia clinical isolates

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Narjess Bostanghadiri ◽  
Abdollah Ardebili ◽  
Zohreh Ghalavand ◽  
Samane Teymouri ◽  
Mahsa Mirzarazi ◽  
...  
Keyword(s):  
Crystal Violet ◽  
Biofilm Formation ◽  
Staining Method ◽  
Clinical Isolates ◽  
Diffusion Method ◽  
Crystal Violet Staining ◽  
Disc Diffusion Method ◽  
Antimicrobial Susceptibility Pattern ◽  
Combination Strategies ◽  
Biofilm Production

Abstract Objective The purpose of the present study was to investigate the antimicrobial susceptibility pattern, biofilm production, and the presence of biofilm genes among the S. maltophilia clinical isolates. A total of 85 clinical isolates of S. maltophilia were collected from patients referred to several hospitals. Susceptibility to antibiotics was investigated by disc diffusion method according to the guidelines of the Clinical and Laboratory Standards Institute (CLSI). By the crystal violet staining method, the capability of biofilm formation was examined. The genes associated with biofilm production were investigated by the PCR-sequencing techniques. Results All isolates were resistant to doripenem, imipenem, and meropenem. Minocycline, trimethoprim/sulfamethoxazole and levofloxacin exhibited the highest susceptibility of 100%, 97.65%, and 95.29%, respectively. The results of crystal violet staining assay showed that all isolates (100%) form biofilm. Moreover, 24 (28.23%), 32 (37.65%), and 29 (34.12%) of isolates were categorized as weak, moderate, and strong biofilm producers, respectively. Biofilm genes including rpfF, spgM and rmlA had an overall prevalence of 89.41% (76/85), 100% (85/85) and 84.71% (72/85), respectively. Rational prescribing of antibiotics and implementation of infection control protocols are necessary to prevent further infection and development of antimicrobial resistance. Combination strategies based on the appropriate antibiotics along with anti-biofilm agents can also be selected to eliminate biofilm-associated infections.

scholarly journals Molecular Investigation of Fibronectin-Binding Protein Genes and Capacity of Biofilm Production in Staphylococcus Aureus Isolated From Clinical Samples

2021 ◽  
Author(s):  
Hossein Jafari Soghondicolaei ◽  
Mohammad Ahanjan ◽  
Mehrdad Gholami ◽  
Bahman Mirzaei ◽  
Hamid Reza Goli
Keyword(s):  
Staphylococcus Aureus ◽  
Biofilm Formation ◽  
Colorimetric Assay ◽  
Binding Protein ◽  
Clinical Isolates ◽  
Diffusion Method ◽  
Clinical Samples ◽  
Biofilm Production ◽  
Fibronectin Binding Protein ◽  
Fibronectin Binding

Abstract Biofilm production increases Staphylococcus aureus resistance to antibiotics and also host defense mechanisms. The current study aims to evaluate the biofilm formation by S. aureus and to determine the prevalence of fibronectin-binding protein genes, also its correlation with drug resistance. In this study, 100 clinical isolates of S. aureus were collected. The antibiotic susceptibility pattern of the isolates was evaluated by the disk agar diffusion method. The ability of biofilm formation in the studied isolates was also determined by microplate colorimetric assay. Then, all isolates were screened by polymerase chain reaction for the fnbA and fnbB genes. Out of 100 clinical isolates of S. aureus, the highest and lowest antibiotic resistance rates were against penicillin (94%) and vancomycin (6%). Thirty-two cases were found to be multi-drug resistant (MDR) among the all strains. The ability of biofilm production was observed in 89% of the isolates. The PCR results showed that the prevalence of fnbA and fnbB genes were 91% and 17%, respectively. Moreover, 100% and 21.8% of the MDR strains harbored the fnbA and fnbB genes respectively. The ability to form biofilm in MDR isolates of S. aureus is more than non-MDR isolates, especially fnbA positive ones. As the bacteria in the biofilm are difficult to kill by antibiotics, attention to the removal or control of the biofilm production seems to be necessary.

Phenotypic and molecular evaluation of biofilm formation in Klebsiella pneumoniae carbapenemase (KPC) isolates obtained from a hospital of Pelotas, RS, Brazil

2021 ◽  
Vol 70 (11) ◽  
Author(s):  
Letícia Roloff Stallbaum ◽  
Beatriz Bohns Pruski ◽  
Suelen Cavalheiro Amaral ◽  
Stella Buchhorn de Freitas ◽  
Daniela Rodriguero Wozeak ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Klebsiella Pneumoniae ◽  
Crystal Violet ◽  
Biofilm Formation ◽  
Staining Method ◽  
Multidrug Resistant ◽  
Crystal Violet Staining ◽  
Content Type ◽  
Klebsiella Pneumoniae Carbapenemase

Introduction. A significant cause of mortality in the intensive care unit (ICU) is multidrug-resistant (MDR) Gram-negative bacteria, such as Klebsiella pneumoniae carbapenemase (KPC). Biofilm production is a key factor in KPC colonization and persistence in the host, making the treatment difficult. Gap Statement. The aim of this study was to evaluate the antibiotic resistance, molecular and phenotypic biofilm profiles of 12 KPC isolates associated with nosocomial infection in a hospital in Pelotas, Rio Grande do Sul, Brazil. Methodology. Clinical isolates were obtained from different sources, identified and characterized by antibiotic resistance and carbapenemase synthesis following the Clinical and Laboratory Standards Institute (CLSI) guidelines. Polymerase chain reaction (PCR) was used to evaluate the presence of carbapenemase (blaKPC ) and biofilm formation-associated genes (fimA, fimH, rmpA, ecpA, mrkD and wabG). Additionally, phenotypic evaluation of in vitro biofilm formation capacity was evaluated by Congo red agar (CRA) assay and the crystal violet staining method. Results. The 12 isolates evaluated in this study presented the blaKPC gene and were positive for synthesizing carbapenemases in vitro. In the carbapenem class, 83.3 % isolates were resistant and 16.7 % intermediately resistant to imipenem and meropenem. Molecular analyses found that the fimA and wabG genes were detected in 75 % of isolates, while fimH and ecpA were detected in 42 % and mrkD were detected in 8.3 % (1). The CRA assay demonstrated that all isolates were slime producers and 91.7 % (11) of isolates were classified as strong and 8.3 % (1) as moderate biofilm producers by the crystal violet staining method. The optical density (OD540nm) for strong biofilm formers ranged from 0.80±0.05 to 2.47±0.28 and was 0.55±0.12 for moderate biofilm formers. Conclusion. Our study revealed a high level of antibiotic resistance and biofilm formation in KPC isolates obtained from a hospital in Pelotas, RS, Brazil.

scholarly journals INHIBITION OF BIOFILM PRODUCING GRAM NEGATIVE CLINICAL ISOLATES AND THEIR ANTIBIOGRAM PATTERN

2021 ◽  
Author(s):  
Ojaswee Shrestha ◽  
Nabina Shrestha ◽  
Sadhana Khanal ◽  
Sushant Pokhrel ◽  
Sujina Maharjan ◽  
...  
Keyword(s):  
Biofilm Formation ◽  
Bacterial Biofilm ◽  
Clinical Isolates ◽  
Diffusion Method ◽  
Resistance Pattern ◽  
Antibiotics Resistance ◽  
Klebsiella Pneumonia ◽  
Isolation And Identification ◽  
Gram Negative ◽  
Biofilm Production

Background: Bacterial biofilm is a major virulence factor that posses a threat to patients leading to chronic infections. Therefore, it is crucial to identify biofilm production as well as their inhibition and reduction. This study was an attempt to investigate biofilm production among gram-negative isolates and assessment of inhibitory and reduction potential of EDTA and DMSO towards them and also observe the antimicrobial resistance pattern among biofilm producers and biofilm non-producer. Methods: Isolation and identification of bacterial isolates were performed by standard microbiological methodology. The antibiotic susceptibility pattern was determined by the Kirby Bauer disk diffusion method and β-lactamases by the combination disk method. Biofilm formation was detected through Tissue Culture Plate(TCP) method, and different concentrations of EDTA and DMSO were used to determine their inhibitory and reduction property against biofilm. Both inhibition and reduction by the various concentration of EDTA and DMSO were analyzed using paired t-test. Results: Among the 110 clinical isolates 61.8% were found to be Multidrug resistance(MDR) with the 33 (30%) produced Extended-spectrum β-lactamases(ESBL), 16 (14.5%)Metalloβ-lactamases(MBL) and 9 (8%)Klebsiella pneumonia carbapenemase(KPC). Biofilm formation was detected in 35.4% of isolates. Biofilm producing organisms showed antibiotics resistance to Cephalosporins, Chloramphenicol, Gentamycin, and Carbapenem. The inhibition and reduction of biofilm were significantly lower (p<0.05) for 1mM of EDTA and 2% of DMSO. Conclusions: EDTA and DMSO were found to possess potential activity against biofilm. Hence, EDTA and DMSO might be used invitro as an effective antibiofilm agent to control the biofilm-associated infection and for a possible therapeutic approach.

Biofilm formation and Antibiotic susceptibility pattern among Staphylococcus aureus in a tertiary care hospital in Kanchipuram: An Evaluation of screening methods for biofilm formation

2016 ◽  
Vol 5 (04) ◽  
pp. 4991
Author(s):  
Abirami Lakshmy Jayachandran* ◽  
Sarasa S. ◽  
Sheila Doris T. ◽  
Balan K. ◽  
Sangeetha Vilwanathan ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Antibiotic Susceptibility ◽  
Biofilm Formation ◽  
Diffusion Method ◽  
Disc Diffusion ◽  
Microtitre Plate ◽  
Disc Diffusion Method ◽  
Plate Method ◽  
Antibiotic Susceptibility Pattern ◽  
Biofilm Production

The ability of Staphylococcus aureus to form biofilms is of significant clinical interest, as biofilm development impacts the efficacy of antimicrobial therapy and the subsequent outcome of an infection. The present study is undertaken to detect the biofilm production and to determine the antibiotic susceptibility pattern among the Staphylococcus aureus isolates. A total of 100 Staphylococcus aureus isolated for the first time from pus, blood, catheter, IV cannulas were included in the study. Biofilm detection was done by tube method and Microtitre plate method. Antibiotic susceptibility was done by Kirby bauer disc diffusion method. Methicillin resistance was detected by Cefoxitin disc diffusion method. By tube method and Microtitre plate method 26% and 46% of the isolates were identified as biofilm producers. By Microtitre plate method, BHI broth (Brain heart infusion broth) and BHI broth with sucrose was used and the difference in the biofilm forming ability was compared. When BHI broth with sucrose was used 69% showed biofilm formation whereas when tested with BHI broth, only 46% were identified as biofilm producers. Good sensitivity was observed for Amikacin (88%) and cefotaxime (82%). MRSA (Methicillin resistant Staphylococcus aureus) was detected among 19% of the isolates. Among the biofilm producers if there are drug resistant bacteria like MRSA the problem becomes challenging and requires combination of several antibiotics. Hence Screening for biofilm production by bacterial isolates should be performed. Infection control program should address the effective execution of disinfection procedures.

scholarly journals Green Tea Polyphenols and Padma Hepaten Inhibit Candida albicans Biofilm Formation

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Yosi Farkash ◽  
Mark Feldman ◽  
Isaac Ginsburg ◽  
Doron Steinberg ◽  
Miriam Shalish
Keyword(s):  
Candida Albicans ◽  
Green Tea ◽  
Crystal Violet ◽  
Biofilm Formation ◽  
Host Cells ◽  
Green Tea Polyphenols ◽  
Crystal Violet Staining ◽  
Biofilm Inhibition ◽  
Therapeutic Concept ◽  
Biofilm Development

Candida albicans (C. albicans) is the most prevalent opportunistic human pathogenic fungus and can cause mucosal membrane infections and invade the blood. In the oral cavity, it can ferment dietary sugars, produce organic acids and therefore has a role in caries development. In this study, we examined whether the polyphenol rich extractions Polyphenon from green tea (PPFGT) and Padma Hepaten (PH) can inhibit the caries-inducing properties of C. albicans. Biofilms of C. albicans were grown in the presence of PPFGT and PH. Formation of biofilms was tested spectrophotometrically after crystal violet staining. Exopolysaccharides (EPS) secretion was quantified using confocal scanning laser microscopy (CSLM). Treated C. albicans morphology was demonstrated using scanning electron microscopy (SEM). Expression of virulence-related genes was tested using qRT-PCR. Development of biofilm was also tested on an orthodontic surface (Essix) to assess biofilm inhibition ability on such appliances. Both PPFGT and PH dose-dependently inhibited biofilm formation, with no inhibition on planktonic growth. The strongest inhibition was obtained using the combination of the substances. Crystal violet staining showed a significant reduction of 45% in biofilm formation using a concentration of 2.5mg/ml PPFGT and 0.16mg/ml PH. A concentration of 1.25 mg/ml PPFGT and 0.16 mg/ml PH inhibited candidal growth by 88% and EPS secretion by 74% according to CSLM. A reduction in biofilm formation and in the transition from yeast to hyphal morphotype was observed using SEM. A strong reduction was found in the expression of hwp1, eap1, and als3 virulence associated genes. These results demonstrate the inhibitory effect of natural PPFGT polyphenolic extraction on C. albicans biofilm formation and EPS secretion, alone and together with PH. In an era of increased drug resistance, the use of phytomedicine to constrain biofilm development, without killing host cells, may pave the way to a novel therapeutic concept, especially in children as orthodontic patients.

scholarly journals ANTIBIOGRAM PROFILE AND BIOFILM FORMING POTENTIAL OF PSEUDOMONAS SPECIES ISOLATED FROM VARIOUS CLINICAL SPECIMENS

2018 ◽  
Vol 11 (10) ◽  
pp. 150
Author(s):  
Jamsheera Cp ◽  
Ethel Suman
Keyword(s):  
Biofilm Formation ◽  
Susceptibility Testing ◽  
Diffusion Method ◽  
Resistance Pattern ◽  
Chi Square ◽  
Clinical Specimens ◽  
Medical College ◽  
Biofilm Production ◽  
Pseudomonas Species ◽  
Chi Square Test

Objective: The present study aimed at finding the resistance pattern of Pseudomonas aeruginosa and other Pseudomonas species isolated from various clinical specimens in the laboratory.Methods: A total of 150 isolates of different species of Pseudomonas obtained from various clinical specimens processed at the Microbiology laboratory of Kasturba Medical College, Manipal Academy of Higher Education, were taken for this study. Antibiotic susceptibility testing was performed by Kirby-Bauer disc diffusion method and interpreted according to the CLSI guidelines. Biofilm assay was performed by modified O’Toole and Kolter method. The results were analyzed using SPSS 17.0 and Student’s unpaired t-test, Kruskal–Wallis, Mann–Whitney, ANOVA, and Chi-square test. p<0.05 was considered statistically significant.Results: Increased resistance was observed by P. aeruginosa to cefotaxime, cotrimoxazole, levofloxacin, ofloxacin, and ticarcillin clavulanate. There was also a good correlation between antibiotic resistance to aztreonam, netilmicin, and ceftazidime and biofilm production. Results of the present study, therefore, demonstrated the occurrence of resistance to various antipseudomonal agents among the biofilm-producing P. aeruginosa isolates.Conclusion: The present study may help in assessing the seriousness of drug resistance caused by biofilm formation in P. aeruginosa and devise strategies through antibiotic policies to minimize such problems.

scholarly journals Evaluation of Antibiotic Resistance Pattern, Alginate and Biofilm Production in Clinical Isolates of Pseudomonas aeruginosa

2021 ◽  
Author(s):  
Fateme DAVARZANI ◽  
Navid SAIDI ◽  
Saeed BESHARATI ◽  
Horieh SADERI ◽  
Iraj RASOOLI ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Biofilm Formation ◽  
Bacterial Resistance ◽  
Antimicrobial Agents ◽  
Clinical Isolates ◽  
Diffusion Method ◽  
Clinical Samples ◽  
Resistance Pattern ◽  
Alginate Production ◽  
Opportunistic Bacteria

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.

scholarly journals Correlation of biofilm formation and antibiotic resistance among clinical and soil isolates of Acinetobacter baumannii in Iraq

2019 ◽  
pp. 1-10 ◽  
Author(s):  
Pakhshan A. Hassan ◽  
Adel K. Khider
Keyword(s):  
Acinetobacter Baumannii ◽  
Congo Red ◽  
Biofilm Formation ◽  
Opportunistic Pathogen ◽  
Microtiter Plate ◽  
Test Tube ◽  
Clinical Isolates ◽  
Diffusion Method ◽  
Biochemical Tests ◽  
Disk Diffusion Method

Acinetobacter baumannii is an opportunistic pathogen that is reported as a major cause of nosocomial infections. The aim of this study was to investigate the biofilm formation by A. baumannii clinical and soil isolates, to display their susceptibility to 11 antibiotics and to study a possible relationship between formation of biofilm and multidrug resistance. During 8 months period, from June 2016 to January 2017, a total of 52 clinical and 22 soil isolates of A. baumannii were collected and identified through conventional phenotypic, chromo agar, biochemical tests, API 20E system, and confirmed genotypically by PCR for blaOXA-51-like gene. Antibiotic susceptibility of isolates was determined by standard disk diffusion method according to Clinical and Laboratory Standard Institute. The biofilm formation was studied using Congo red agar, test tube, and microtiter plate methods. The clinical isolates were 100% resistance to ciprofloxacin, ceftazidime, piperacillin, 96.15% to gentamicin, 96.15% to imipenem, 92.31% to meropenem, and 78.85% to amikacin. The soil A. baumannii isolates were 100% sensitive to imipenem, meropenem, and gentamicin, and 90.1% to ciprofloxacin. All A. baumannii isolates (clinical and soil) were susceptible to polymyxin B. The percentage of biofilm formation in Congo red agar, test tube, and microtiter plate assays was 10.81%, 63.51%, and 86.48%, respectively. More robust biofilm former population was mainly among non-MDR isolates. Isolates with a higher level of resistance tended to form weaker biofilms. The soil isolates exhibited less resistance to antibiotics than clinical isolates. However, the soil isolates produce stronger biofilms than clinical isolates.

scholarly journals Association between Biofilm-Production and Antibiotic Resistance in Uropathogenic Escherichia coli (UPEC): An In Vitro Study

Diseases ◽  
2020 ◽  
Vol 8 (2) ◽  
pp. 17 ◽  
Author(s):  
Payam Behzadi ◽  
Edit Urbán ◽  
Márió Gajdács
Keyword(s):  
Escherichia Coli ◽  
Biofilm Formation ◽  
In Vitro Study ◽  
Point Of View ◽  
Diffusion Method ◽  
Medical Attention ◽  
Disk Diffusion Method ◽  
Biofilm Production ◽  
Tract Infections

Urinary tract infections (UTIs) are among the most common infections requiring medical attention worldwide. The production of biofilms is an important step in UTIs, not only from a mechanistic point of view, but this may also confer additional resistance, distinct from other aspects of multidrug resistance (MDR). A total of two hundred and fifty (n = 250) Escherichia coli isolates, originating from clean-catch urine samples, were included in this study. The isolates were classified into five groups: wild-type, ciprofloxacin-resistant, fosfomycin-resistant, trimethoprim-sulfamethoxazole-resistant and extended spectrum β-lactamase (ESBL)-producing strains. The bacterial specimens were cultured using eosine methylene blue agar and the colony morphology of isolates were recorded. Antimicrobial susceptibility testing was performed using the Kirby–Bauer disk diffusion method and E-tests. Biofilm-formation of the isolates was carried out with the crystal violet tube-adherence method. n = 76 isolates (30.4%) produced large colonies (>3 mm), mucoid variant colonies were produced in n = 135 cases (54.0%), and n = 119 (47.6%) were positive for biofilm formation. The agreement (i.e., predictive value) of mucoid variant colonies in regard to biofilm production in the tube-adherence assay was 0.881 overall. Significant variation was seen in the case of the group of ESBL-producers in the ratio of biofilm-producing isolates. The relationship between biofilm-production and other resistance determinants has been extensively studied. However, no definite conclusion can be reached from the currently available data.

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