# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 2194 | 0 | 1.0000 | Detection of Antiseptic-Resistance Genes in Pseudomonas and Acinetobacter spp. Isolated From Burn Patients. BACKGROUND: Quaternary ammonium compounds (QAC), which contain benzalkonium chloride as the most widely used agent, are employed as wound and skin antiseptics, as well as disinfectants in hospitals. The resistance mechanism to disinfectants is usually determine by genes which are related to resistance to quaternary ammonium compounds, namely, qacE, qacΔE1, qacΔE1 that are found in Gram-negative bacteria. OBJECTIVES: The aim of this study was to determine the incidence of antiseptic resistance genes, qacE and qacΔE1, in clinical isolates of Pseudomonas aeruginosa and Acinetobacter bumanii. MATERIALS AND METHODS: In this study, 83 clinical isolates of Pseudomonas aeruginosa, and 5 isolates of Acinetobacter baumannii from burn hospitals in Tehran and Isfahan provinces in 2010-2011, were tested by the PCR method. RESULTS: Out of the 83 clinical isolates of Pseudomonas aeruginosa, 49 isolates (50%) had the qacE gene, and 76 isolates (91.5%) had the qacΔE1 gene. In addition, in 5 isolates of Acinetobacter bumanii, 2 isolates (40%) had the qacE gene, and 4 isolates (80%) had the qacΔE1 gene. CONCLUSIONS: This study shows that the genes which harbored resistance to quaternary ammonium compound antiseptics are widespread among Pseudomonas aeruginosa and Acinetobacter bumanii isolates in burn patients. | 2014 | 24872941 |
| 2195 | 1 | 0.9998 | Detection of Biocide Resistance Genes (qacE and qacΔE1) in Pseudomonas spp Isolated from Patients with CSOM at Mymensingh Medical College Hospital, Bangladesh. Biocides, including disinfectants and antiseptics, are used for a variety of topical and hard surface applications in health care facilities. Biocides play a significant role for preventing and controlling nosocomial infections. However, failures in the antimicrobial activities of biocides have been reported. The resistance mechanism to disinfectants is usually determined by genes which are related to resistance to quaternary ammonium compounds, namely, qacE, qacΔE1 that are found in Gram-negative bacteria. The aim of this study is to detect the prevalence of Biocides resistance genes, qacE and qacΔE1, in clinical isolates of Pseudomonas spp. It was carried out from March 2017 to July 2018 in the department of Microbiology, Mymensingh Medical College, Mymensingh, Bangladesh. Samples were collected from Outpatient of ENT department, MMCH. In this study, 300 clinical samples of CSOM cases were tested by the PCR method. The present study shows detection of biocide resistance genes (qacE, qacΔE1) among 87 isolated Pseudomonas spp by uniplex PCR. Among 72 clinical isolates of Pseudomonas aeruginosa 67(93.05%) had the gene qacEΔ1 and 25(34.72%) had the gene qacE. In addition other 15 Pseudomonas spp 3(20%) isolates had the qacEΔ1 gene and 2(13.33%) isolates had the qacE gene. In this study there is a marked difference in detection of the qacEΔ1 gene between the MDR and non MDR P. aeruginosa isolates. The qacEΔ1 was identified in 50 of 54(92.59%) MDR isolates and 7 of 18(38.89%) non MDR strains respectively. While gene qacE was detect 25(46.29%) MDR isolates and did not show any qacEΔ1gene in non MDR isolates. This study shows that the genes, qacE, qacΔE1 are widespread among Pseudomonas aeruginosa, they are higher in MDR strains than non MDR strains. | 2021 | 34605462 |
| 2172 | 2 | 0.9997 | Detection of blaPER-1 & blaOxa10 among imipenem resistant isolates of Pseudomonas aeruginosa isolated from burn patients hospitalized in Shiraz Burn Hospital. BACKGROUND AND OBJECTIVES: Pseudomonas aeruginosa is one of the most important Gram negative opportunistic bacteria which causes infection among burn patients. Resistance to the antibiotics in this group of bacteria is increased due to the activity of extended spectrum β-lactamase (ESBLs) genes. In the current study, we investigated the prevalence of two genes (blaPER-1 & blaOxa10 ) related β-lactamase genes among imipenem resistance clinical isolates of P. aeruginosa in hospitalized patients. MATERIALS AND METHODS: From May 2010 to March 2011, 270 P. aeruginosa isolated from hospitalized burned patients' wounds in Shiraz Burn Hospital, were tested for Imipenem resistance by disk diffusion method. Presence of ESBLs exo-enzyme, blaPER-1 and blaOxa10 genes were also evaluated in the resistant isolate. RESULTS: 210 (77.7%) of 270 P. aeruginosa isolates were resistant to imipenem. blaPER-1 and blaOxa10 were detected among 168 (80.0%) of imipenem resistant isolates. Furthermore, 160 (76.2%) of them had blaOxa10 gene and 84 (40.0%) of them had blaPER-1 while 63 (30.0%) resistant isolates contained both genes simultaneously. CONCLUSION: This study showed a high prevalence of blaPER-1 and blaOxa10 genes in hospitalized burn patients in south west of Iran. Therefore, it's highly recommended to perform such tests routinely to evaluate the resistance pattern in order to better antibiotic selection in the burned patients. | 2015 | 26644867 |
| 935 | 3 | 0.9996 | Evaluating the Saliva of Burn ICU Patients for Resistant Infections Harbor Metallo-β-Lactamase Genes. Pseudomonas aeruginosa and Acinetobacter baumannii are the bacteria which increasingly account for nosocomial infections. Due to high virulence, the rate of Multi-Drug Resistance (MDR) and limited availability of new agents, these infections create significant clinical burdens, making it important to identify the possible sources of their occurrence. The aim of this study was to assess non-lactose fermenting bacteria and their metallo-β-lactamase (MBLs) genes expression in the Burn Intensive Care Unit (BICU) patients' saliva samples. This cross-sectional study was conducted from 2017 to 2018 on 124 saliva samples of BICU patients. Identified isolates were evaluated for drug susceptibility by disc diffusion method. MBLs production isolates were detected by Modified Hodge test and Imipenem-EDTA Combined disk. MBLs related genes were evaluated by polymerase chain reaction (PCR). A total of 86 Gram negative non-lactose fermenting bacteria (38; A. baumannii) and (48; P. aeruginosa), were detected. All of the A. baumannii isolates were resistant to Carbapenems, while more than 90% of them were sensitive to Colistin. However, the highest sensitivity in P. aeruginosa isolates was related to Carbapenems and Colistin. More than 95% of A. baumannii and 32% of P. aeruginosa were detected MDR. MBLs production was confirmed in 9 (33.33%) P. aeruginosa and 18 (66.67%) A. baumannii isolates. The blaVIM was the most prevalent gene, while this gene was detected in all of MBLs positive strains. This study confirmed the prevalence of carbapenemase producer Gram-negative bacilli in the saliva of BICU patients. The results of the present study provide a new data set about saliva infection source that could lead to the proper antibiotic regimen and better control of drug resistance. | 2020 | 31930340 |
| 2356 | 4 | 0.9996 | Occurrence of Multiple-Drug Resistance Bacteria and Their Antimicrobial Resistance Patterns in Burn Infections from Southwest of Iran. Burn infection continues to be a major issue of concern globally and causes more harm to developing countries. This study aimed to identify the aerobic bacteriological profiles and antimicrobial resistance patterns of burn infections in three hospitals in Abadan, southwest Iran. The cultures of various clinical samples obtained from 325 burn patients were investigated from January to December 2019. All bacterial isolates were identified based on the standard microbiological procedures. Antibiotic susceptibility tests were performed according to the CLSI. A total of 287 bacterial species were isolated from burn patients. Pseudomonas aeruginosa was the most frequent bacterial isolate in Gram-negative bacteria and S. epidermidis was the most frequent species isolated in Gram-positive bacteria. The maximum resistance was found to ampicillin, gentamicin, ciprofloxacin, while in Gram-negative bacteria, the maximum resistance was found to imipenem, gentamicin, ciprofloxacin, ceftazidime, and amikacin. The occurrence of multidrug resistance phenotype was as follows: P. aeruginosa (30.3%), Enterobacter spp (11.1%), Escherichia coli (10.5%), Citrobacter spp (2.1%), S. epidermidis (2.8%), S. aureus, and S. saprophyticus (0.7%). Owing to the diverse range of bacteria that cause burn wound infection, regular investigation, and diagnosis of common bacteria and their resistance patterns is recommended to determine the proper antibiotic regimen for appropriate therapy. | 2022 | 34236077 |
| 2152 | 5 | 0.9996 | Immunological and molecular detection of biofilm formation and antibiotic resistance genes of Pseudomonas aeruginosa isolated from urinary tract. BACKGROUND AND OBJECTIVES: Pseudomonas aeruginosa (P. aeruginosa) is one of the most common causes of hospital-acquired infections. It is associated with high morbidity and healthcare costs, especially when appropriate antibiotic treatment is delayed. Antibiotic selection for patients with P. aeruginosa infections is challenging due to the bacteria's inherent resistance to many commercially available antibiotics. This study investigated antibiotic-resistance genes in isolated bacteria, which play a key role in disease pathogenesis. MATERIALS AND METHODS: 100 samples out of the 140 samples collected from urinary tract infections (UTIs) cases between December 15(th), 2022, and April 15(th), 2023, were included in the study. Identification of bacterial isolates was based on colony morphology, microscopic examination, biochemical tests, and the Vitek-2 system. Antibiotic resistance genes; Aph(3)-llla, ParC, Tet/tet(M), and aac(6´)-Ib-cr were tested by polymerase chain reaction (PCR). RESULTS: The obtained results were based on bacterial identifications of 81 clinical samples. Only 26 (32%) of these isolates were P. aeruginosa, 21 (26%) were Escherichia coli, and 18 (22.2%) were other bacteria. These isolates were used to detect four genes including tet(M), Aph(3)-llla, Par-c, and aac(6´)-Ib-cr. Four types of primers were used for PCR detection. The results showed that 11/14 (78.57%) carried the tet(M) gene, 10/14 (71.42%) carried the Aph(3)-llla gene, 14/14 (100%) carried the Par-c gene, and 10/14 (71.42%) of the isolates carried the aac(6´)-Ib-cr gene. The biofilm formation examining the esp gene, showed that 9 (64.28) isolates carried this gene. CONCLUSION: The inability of antibiotics to penetrate biofilms is an important factor contributing to the antibiotic tolerance of bacterial biofilms. | 2025 | 40612720 |
| 2160 | 6 | 0.9996 | Detection of AdeAB, TetA, and TetB efflux pump genes in clinical isolates of tetracycline-resistant Acinetobacter baumannii from patients of Suez Canal University Hospitals. BACKGROUND: Acinetobacter baumannii is an opportunistic bacteria associated primarily with hospital-acquired infections. Its tendency to acquire or donate resistance genes to neighboring bacteria is a major concern. Tetracyclines have shown promise in treating A. baumannii infections, but tetracycline resistance is growing globally in A. baumannii isolates. OBJECTIVES: The study aimed to study (1) the prevalence of multidrug-resistant (MDR) A. baumannii infections at Suez Canal University Hospitals, (2) the distribution of efflux pump genes AdeA &B, TetA, and TetB, and (3) the effect of efflux pump inhibitor (CCCP) on tetracycline-resistant isolates. METHODS: Clinical samples (457) were collected (blood, urine, sputum, ETA, pus, and pleural fluid), followed by A. baumannii isolation and identification, PCR detection of efflux pump genes, and detection of tetracycline susceptibility and its MIC before and after treatment with the efflux pump inhibitor (CCCP). RESULTS: A total of 31 A. baumannii isolates were recovered (6.78%). The highest rate of isolation was from the ICU (48.3%) from the ET aspirate samples (48.3%). The efflux system AdeA and TetB genes were distributed in 100% of isolates, whereas AdeB was found in 93.5% of isolates and the TetA gene in 87.1% of isolates. All A. baumannii isolates were MDR showing resistance to three or more classes of antibiotics. 45% of the isolates showed a 4-fold reduction of MIC and 12.9% showed a 2-fold reduction in the MIC. CONCLUSIONS: Efflux pump is an important mechanism for tetracycline resistance among A. baumannii isolates. | 2025 | 39905304 |
| 2153 | 7 | 0.9996 | Molecular Characterization and Epidemiology of Antibiotic Resistance Genes of β-Lactamase Producing Bacterial Pathogens Causing Septicemia from Tertiary Care Hospitals. Septicemia is a systematic inflammatory response and can be a consequence of abdominal, urinary tract and lung infections. Keeping in view the importance of Gram-negative bacteria as one of the leading causes of septicemia, the current study was designed with the aim to determine the antibiotic susceptibility pattern, the molecular basis for antibiotic resistance and the mutations in selected genes of bacterial isolates. In this study, clinical samples (n = 3389) were collected from potentially infected male (n = 1898) and female (n = 1491) patients. A total of 443 (13.07%) patients were found to be positive for bacterial growth, of whom 181 (40.8%) were Gram-positive and 262 (59.1%) were Gram-negative. The infected patients included 238 males, who made up 12.5% of the total number tested, and 205 females, who made up 13.7%. The identification of bacterial isolates revealed that 184 patients (41.5%) were infected with Escherichia coli and 78 (17.6%) with Pseudomonas aeruginosa. The clinical isolates were identified using Gram staining biochemical tests and were confirmed using polymerase chain reaction (PCR), with specific primers for E. coli (USP) and P. aeruginosa (oprL). Most of the isolates were resistant to aztreonam (ATM), cefotaxime (CTX), ampicillin (AMP) and trimethoprim/sulfamethoxazole (SXT), and were sensitive to tigecycline (TGC), meropenem (MEM) and imipenem (IPM), as revealed by high minimum inhibitory concentration (MIC) values. Among the antibiotic-resistant bacteria, 126 (28.4%) samples were positive for ESBL, 105 (23.7%) for AmpC β-lactamases and 45 (10.1%) for MBL. The sequencing and mutational analysis of antibiotic resistance genes revealed mutations in TEM, SHV and AAC genes. We conclude that antibiotic resistance is increasing; this requires the attention of health authorities and clinicians for proper management of the disease burden. | 2023 | 36978484 |
| 2204 | 8 | 0.9996 | Multidrug resistance pattern of bacterial agents isolated from patient with chronic sinusitis. BACKGROUND: Treatment of chronic sinusitis is complicated due to increase of antibiotic-resistant bacteria. The aim of this study was to determine the multidrug resistance (MDR) pattern of the bacteria causing chronic sinusitis in north of Iran. METHODS: This cross-sectional study was carried out on patients with chronic sinusitis. Bacterial susceptibility to antimicrobial agents was determined according to the CLSI 2013 standards. Double-disk synergy (DDS) test was performed for the detection of extended-spectrum beta-lactamase (ESBL) producing bacteria; also methicillin-resistant Staphylococcus (MRSA) strains were identified by MRSA screen agar. The MDR isolates were defined as resistant to 3 or more antibiotics. Data were analyzed using SPSS 17 software. Descriptive statistics was used to describe the features of the data in this study. RESULTS: The rate of ESBL-producing bacteria was 28.75-37.03% among enterobacteriaceae and the rate of MRSA was 42.75%-60% among Staphylococcus strains. The most detectable rate of the MDR bacterial isolates was Gram-negative bacteria 39 (76.47%) and Enterobacter spp. 19(70.37%) was the most multidrug resistant isolate among Gram negative bacteria. Also 36 (73.46%) of the gram positive bacterial isolated were multidrug resistance and Staphylococcus aureus 9(90%) was the most MDR among Gram positive bacteria. CONCLUSION: Antimicrobial resistance is increasing in chronic bacterial sinusitis. The emergence of MRSA and ESBL bacteria causing chronic sinusitis is increasing. | 2016 | 27386063 |
| 2312 | 9 | 0.9996 | Metallo-beta-Lactamase VIM-1, SPM-1, and IMP-1 Genes Among Clinical Pseudomonas aeruginosa Species Isolated in Zahedan, Iran. BACKGROUND: One of the major clinical problems regarding Pseudomonas aeruginosa is attributed to metallo-beta-lactamases (MBL). This group of enzymes is a subset of beta lactamases which belong to group B of Ambler classification and cause hydrolysis of carbapenems. Based on epidemiological studies conducted worldwide, it is proved that prevalence of genes coding MBLs in P. aeruginosa species are different in various geographic zones and even in various hospitals. Therefore, according to the clinical importance of organisms generating MBLs, it is necessary to identify and control these bacteria in hospitals for therapeutic purposes. OBJECTIVES: The current study aimed to investigate the Metallo-beta-Lactamase VIM-1, SPM-1, and IMP-1 genes among clinical P. aeruginosa species isolated in Zahedan, Iran. MATERIALS AND METHODS: The current study investigated the presence of MBL through phenotypic and genotypic methods and also the pattern of antibiotic resistance in P. aeruginosa species isolated in hospitals. The Minimum Inhibitory Concentration (MIC) against imipeneme was measured for 191 P. aeruginosa species isolated from Zahedan hospitals after identification through biochemical methods and determination of the antibiotic resistance pattern. Strains with MIC > 4 µg/mL were studied by phenotypic and genotypic methods. RESULTS: The rate of resistance against imipeneme was 5.7% and after carrying out the phenotypic experiments, nine species were identified as of MBL producer. Seven species were confirmed by Polymerase Chain Reaction (PCR) method. Gene VIM-1 was the predominant gene among the positive (antibiotic resistant) species. CONCLUSIONS: The study results showed that MBL genes were present in some of the species isolated from Zahedan hospitals. Regarding the importance of MBL producer bacteria in hospitals, quick identification and evaluation of these clinical species can be considered as an important and basic step for treatment and control of pseudomonad infections. | 2015 | 26034547 |
| 2159 | 10 | 0.9996 | Involvement of the AcrAB Efflux Pump in Ciprofloxacin Resistance in Clinical Klebsiella Pneumoniae Isolates. BACKGROUND: Increasing prevalence of multiple antibiotic resistance in Klebsiella pneumoniae strains confines the therapeutic options used to treat bacterial infections. OBJECTIVE: We aimed in this study to investigate the role of AcrAB and qepA efflux pumps and AAC(6')-Ib-cr enzyme in ciprofloxacin resistance and to detect the RAPD-PCR fingerprint of K. pneumoniae isolates. METHODS: A total of , 117 K. pneumoniae isolates were collected from hospitalized patients in three hospitals in Tehran, Iran, from August 2013 to March 2014. Antimicrobial susceptibility tests were performed by the disk diffusion method. Molecular identification and expression level of encoding quinolone resistance genes, acrA, acrB, qepA, and aac(6')-Ib-cr, were performed by PCR and real-- time PCR assays, respectively. All the K. pneumoniae isolates containing the mentioned genes were used simultaneously for RAPD-PCR typing. RESULTS: Colistin and carbapenems were the most efficient antibiotics against the clinical isolates of K. pneumoniae. PCR assay demonstrated that among the 117 isolates, 110 (94%) and 102 (87%) were positive for acrA and acrB gene and 5 (4%) and 100 (85%) isolates showed to have qepA and aac(6')-Ib-cr genes, respectively. Determination for AcrAB pump expression in 21% of strains demonstrated an increased expression, and the mean increase expression for acrB genes was 0.5-81. The results of RAPD-PCR reflected that in 95% CI, all isolates belonged to a clone. CONCLUSION: A high prevalence of genes encoding quinolone resistance in K. pneumoniae was detected in clinical samples. Therefore, the control of infection and prevention of drug-resistant bacteria spread need careful management of medication and identification of resistant isolates. | 2021 | 32888276 |
| 2147 | 11 | 0.9996 | Identification of Genes Coding Aminoglycoside Modifying Enzymes in E. coli of UTI Patients in India. This study is to probe the pattern of antibiotic resistance against aminoglycosides and its mechanism in E. coli obtained from patients from Chennai, India. Isolation and identification of pathogens were done on MacConkey agar. Antimicrobial sensitivity testing was done by disc diffusion test. The identification of genes encoding aminoglycoside modifying enzymes was done by Polymerase Chain Reaction (PCR). Out of 98 isolates, 71 (72.45%) isolates were identified as E. coli and the remaining 27 (27.55%) as other bacteria. Disc diffusion method results showed a resistance level of 72.15% for streptomycin, 73.4% for gentamicin, 63.26% for neomycin, 57.14% for tobramycin, 47.9% for netilmicin, and 8.16% for amikacin in E. coli. PCR screening showed the presence of four genes, namely, rrs, aacC2, aacA-aphD, and aphA3, in their plasmid DNA. The results point towards the novel mechanism of drug resistance in E. coli from UTI patients in India as they confirm the presence of genes encoding enzymes that cause resistance to aminoglycoside drugs. This could be an alarm for drug prescription to UTI patients. | 2016 | 27403451 |
| 2165 | 12 | 0.9996 | Distribution and analysis of the resistance profiles of bacteria isolated from blood cultures in the intensive care unit. PURPOSE: To investigate the distribution characteristics and drug resistance of pathogenic bacteria in bloodstream infections, providing a basis for rational clinical treatment. PATIENTS AND METHODS: Retrospective analysis of 1,282 pathogenic strains isolated from blood cultures in the intensive care unit (ICU) of the Second Affiliated Hospital of Xi'an Jiaotong University from January 1, 2019, to December 31, 2022. RESULTS: Gram-positive bacteria (52.0%) slightly predominated over gram-negative bacteria (48.0%). The top three gram-positive bacteria were Coagulase-negative Staphylococcus (28.0%), Enterococcus faecium (7.4%), and Staphylococcus aureus (6.6%). Staphylococci exhibited a high resistance rate to penicillin, oxacillin, and erythromycin; no strains resistant to vancomycin or linezolid were found. Among the Enterococci, Enterococcus faecium had a high resistance rate to penicillin, ampicillin, and erythromycin. Two strains of Enterococcus faecalis were resistant to linezolid, but none to vancomycin. The top three gram-negative bacteria were Escherichia coli (14.7%), Klebsiella pneumoniae (14.0%), and Acinetobacter baumannii (4.8%). The resistance rate of Escherichia coli to carbapenems increased from 0.0 to 2.3%. Acinetobacter baumannii reached 100% carbapenem resistance (up from 75.0%), while Klebsiella pneumoniae demonstrated 21.1-80.4% resistance to various carbapenems. CONCLUSION: The isolation rate of gram-positive bacteria in patients with bloodstream infection in the ICU of the Second Affiliated Hospital of Xi'an Jiaotong University was slightly higher than that of gram-negative bacteria. The alarming carbapenem resistance among gram-negative pathogens and emerging linezolid resistance in Enterococci demand urgent clinical interventions, including enhanced surveillance, antimicrobial stewardship, and novel therapeutic strategies. | 2025 | 40727562 |
| 2220 | 13 | 0.9996 | Rapid detection and molecular survey of blaVIM, blaIMP and blaNDM genes among clinical isolates of Acinetobacter baumannii using new multiplex real-time PCR and melting curve analysis. BACKGROUND: Acinetobacter baumannii is a cosmopolitan bacterium that is frequently reported from hospitalized patients, especially those patients who admitted in the intensive care unit. Recently, multiplex real-time PCR has been introduced for rapid detection of the resistance genes in clinical isolates of bacteria. The current study aimed to develop and evaluate multiplex real-time PCR to detect common resistance genes among clinical isolates of A. baumannii. RESULTS: Multiplex real-time PCR based on melting curve analysis showed different T(m) corresponding to the amplified fragment consisted of 83.5 °C, 93.3 °C and 89.3 °C for blaIMP, blaVIM and blaNDM, respectively. Results of multiplex real-time PCR showed that the prevalence of blaIMP, blaVIM and blaNDM among the clinical isolates of A. baumannii were 5/128(3.9%), 9/128(7.03%) and 0/128(0%), respectively. Multiplex real-time PCR was able to simultaneously identify the resistance genes, while showed 100% concordance with the results of conventional PCR. CONCLUSIONS: The current study showed that blaVIM, was the most prevalent MBL gene among the clinical isolates of A. baumannii while no amplification of blaNDM was seen. Multiplex real-time PCR can be sensitive and reliable technique for rapid detection of resistance genes in clinical isolates. | 2019 | 31182026 |
| 2307 | 14 | 0.9996 | Phenotypic and molecular characterization of antimicrobial resistance and virulence factors in Pseudomonas aeruginosa clinical isolates from Recife, State of Pernambuco, Brazil. INTRODUCTION: The emergence of carbapenem resistance mechanisms in Pseudomonas aeruginosa has been outstanding due to the wide spectrum of antimicrobial degradation of these bacteria, reducing of therapeutic options. METHODS: Sixty-one clinical strains of P. aeruginosa isolated from five public hospitals in Recife, Pernambuco, Brazil, were examined between 2006 and 2010, aiming of evaluating the profiles of virulence, resistance to antimicrobials, presence of metallo-β-lactamase (MBL) genes, and clonal relationship among isolates. RESULTS: A high percentage of virulence factors (34.4% mucoid colonies; 70.5% pyocyanin; 93.4% gelatinase positives; and 72.1% hemolysin positive) and a high percentage of antimicrobial resistance rates (4.9% pan-resistant and 54.1% multi-drug resistant isolates) were observed. Among the 29 isolates resistant to imipenem and/or ceftazidime, 44.8% (13/29) were MBL producers by phenotypic evaluation, and of these, 46.2% (6/13) were positive for the blaSPM-1 gene. The blaIMP and blaVIM genes were not detected. The molecular typing revealed 21 molecular profiles of which seven were detected in distinct hospitals and periods. Among the six positive blaSPM-1 isolates, three presented the same clonal profile and were from the same hospital, whereas the other three presented different clonal profiles. CONCLUSIONS: These results revealed that P. aeruginosa is able to accumulate different resistance and virulence factors, making the treatment of infections difficult. The identification of blaSPM-1 genes and the dissemination of clones in different hospitals, indicate the need for stricter application of infection control measures in hospitals in Recife, Brazil, aiming at reducing costs and damages caused by P. aeruginosa infections. | 2012 | 23295873 |
| 923 | 15 | 0.9996 | Prevalence of Oxacillinase Genes in Clinical Multidrug-Resistant Gram-Negative Bacteria. BACKGROUND: The emergence of OXA-type beta-lactamases has become a significant threat to public healthcare systems and may lead to prolonged hospital stays and increased mortality rates among affected patients. This study aimed to determine the prevalence of oxacillinase resistance (OXA) genes in multidrug-resistant (MDR) Gram-negative bacteria. METHODS: One hundred and six clinical isolates were collected from a stock of Gram-negative isolates and were identified and tested for antibiotic susceptibility and presence of OXA genes using polymerase chain reaction (PCR). RESULTS: The most common detected isolate was Klebsiella pneumoniae (36.8%), followed by Escherichia coli (33%), Pseudomonas aeruginosa (16%), and Acinetobacter baumannii (14.2%). Out of these isolates, 97.4%, 87.2%, 84.6%, and 79.5% were resistant to ampicillin/sulbactam, cefotaxime, ceftazidime, and aztreonam, respectively. PCR results confirmed the presence of one or more OXA genes in 34% of the samples studied. The blaOXA-1 and blaOXA-10 genes were the most highly detected genes, followed by blaOXA-4 and blaOXA-51. The total number of Pseudomonas aeruginosa isolates was confirmed to carry at least one OXA gene (70.6%), whereas Acinetobacter baumannii, Klebsiella pneumoniae, and Escherichia coli were confirmed to carry at least one OXA gene (53.3, 28.2, and 22.9%, respectively). There was a significant association (p < 0.05) between the resistance genes and the type of isolate. CONCLUSIONS: Pseudomonas aeruginosa and Acinetobacter baumannii are the most common MDR Gram-negative strains carrying OXA-type beta-lactamase genes. Monitoring of MDR pathogens in Gram-negative bacteria must be continuously undertaken to implement effective measures for infection control and prevention. | 2025 | 40066541 |
| 2146 | 16 | 0.9996 | Study of aminoglycoside resistance genes in enterococcus and salmonella strains isolated from ilam and milad hospitals, iran. BACKGROUND: Aminoglycosides are a group of antibiotics that have been widely used in the treatment of life-threatening infections of Gram-negative bacteria. OBJECTIVES: This study aimed to evaluate the frequency of aminoglycoside resistance genes in Enterococcus and Salmonella strains isolated from clinical samples by PCR. MATERIALS AND METHODS: In this study, 140 and 79 isolates of Enterococcus and Salmonella were collected, respectively. After phenotypic biochemical confirmation, 117 and 77 isolates were identified as Enterococcus and Salmonella, respectively. After the biochemical identification of the isolates, antibiotic susceptibility for screening of resistance was done using the Kirby-Bauer method for gentamicin, amikacin, kanamycin, tobramycin and netilmycin. DNA was extracted from resistant strains and the presence of acc (3)-Ia, aac (3')-Ib, acc (6)-IIa ,16SrRNA methylase genes (armA and rat) was detected by PCR amplification using special primers and positive controls. RESULTS: Enterococcus isolates have the highest prevalence of resistance to both kanamycin and amikacin (68.4%), and Salmonella isolates have the highest prevalence of resistance against kanamycin (6.9%). Ninety-three and 26 isolates of Enterococcus and Salmonella at least were resistant against one of the aminoglycosides, respectively. Moreover, 72.04%, 66.7%, and 36.6% of the resistant strains of Enterococcus had the aac (3')-Ia, aac (3')-IIa, and acc (6')-Ib genes, respectively. None of the Salmonella isolates have the studied aminoglycoside genes. CONCLUSIONS: Our results indicate that acetylation genes have an important role in aminoglycoside resistance of the Enterococcus isolates from clinical samples. Moreover, Salmonella strains indicate very low level of aminoglycoside resistance, and aminoglycoside resistance genes were not found in Salmonella isolates. These results indicate that other resistance mechanisms, including efflux pumps have an important role in aminoglycoside resistance of Salmonella. | 2015 | 26034551 |
| 2362 | 17 | 0.9996 | Distribution of pathogenic bacteria and antimicrobial sensitivity of eye infections in Suzhou. AIM: To investigate the types of bacteria in patients with eye infections in Suzhou and their drug resistance to commonly used antibacterial drugs. METHODS: The clinical data of 155 patients were retrospectively collected in this study, and the pathogenic bacteria species and drug resistance of each pathogenic bacteria were analyzed. RESULTS: Among the 155 patients (age from 12 to 87 years old, with an average age of 57, 99 males and 56 females) with eye infections (160 eyes: 74 in the left eye, 76 in the right eye and 5 in both eyes, all of which were exogenous), 71 (45.81%) strains were gram-positive bacteria, 23 (14.84%) strains were gram-negative bacteria and 61 (39.35%) strains were fungi. Gram-positive bacteria were highly resistant to penicillin and erythromycin (78.87% and 46.48% respectively), but least resistant to vancomycin at 0. Gram-negative bacteria were highly resistant to cefoxitin and compound sulfamethoxazole (100% and 95.65% respectively), but least resistant to meropenem at 0. Comparison of the resistance of gram-positive and gram-negative bacteria to some drugs revealed statistically significant differences (P<0.05) in the resistance of both to cefoxitin, cotrimoxazole, levofloxacin, cefuroxime, ceftriaxone and ceftazidime, and both had higher rates of resistance to gram-negative bacteria than to gram-positive bacteria. The distribution of bacterial infection strains showed that Staphylococcus epidermidis was the most common strain in the conjunctiva, cornea, aqueous humor or vitreous body and other eye parts. Besides, Fusarium and Pseudomonas aeruginosa were also among the most common strains of conjunctival and corneal infections. CONCLUSION: Gram-positive bacteria are the dominant bacteria in eye infections, followed by gram-negative bacteria and fungi. Considering the resistance of gram-negative bacteria to multiple drugs, monitoring of bacteria should be strengthened in eye bacterial infections for effective prevention and control to reduce complications caused by eye infections. | 2024 | 38638249 |
| 2149 | 18 | 0.9996 | Cross-Resistance and the Mechanisms of Cephalosporin-Resistant Bacteria in Urinary Tract Infections Isolated in Indonesia. Urinary tract infection (UTI) by antibiotic-resistant strains has become increasingly problematic, with trends that differ from country to country. This study examined cross-resistance and the mechanisms of cephalosporin resistance in UTI-causative bacteria isolated in Indonesia. Antibiotic susceptibility tests based on Clinical Laboratory Standards Institute (CLSI) standards were done for UTI-causative strains (n = 50) isolated from patients in Indonesia in 2015-2016 and showed resistance against the third-generation cephalosporin. Mechanistic studies were carried out to confirm the presence of extended-spectrum β-lactamase (ESBL) genes, carbapenemase-related genes, the fosA3 gene related to fosfomycin resistance, and mutations of quinolone-resistance-related genes. Isolated UTI-causative bacteria included Escherichia coli (64.0%), Pseudomonas aeruginosa (16.0%), Klebsiella pneumoniae (10.0%), and others (10.0%). These strains showed 96.0% susceptibility to amikacin, 76.0% to fosfomycin, 90.0% to imipenem, 28.0% to levofloxacin, 92.0% to meropenem, and 74.0% to tazobactam/piperacillin. ESBL was produced by 68.0% of these strains. Mechanistic studies found no strains with carbapenemase genes but 6.0% of strains had the fosA3 gene. Seventy-two % of the strains had mutations in the gyrA gene and 74.0% in the parC gene. Most E. coli strains (87.5%) had Ser-83 → Leu and Asp-87 → Asn in gyrA and 93.8% of E. coli had Ser-80 → Ile in parC. There were significant correlations among mutations in gyrA and parC, and fosA3 gene detection (P < 0.05), respectively. To our knowledge, this is the first mechanistic study of antibiotic-cross-resistant UTI-causative bacteria in Indonesia. Further studies with a longer period of observation are necessary, especially for changes in carbapenem resistance without carbapenemase-related genes. | 2021 | 33713209 |
| 2175 | 19 | 0.9996 | Drug-resistant genes carried by Acinetobacter baumanii isolated from patients with lower respiratory tract infection. BACKGROUND: Acinetobacter baumanii (A. baumanii ) remains an important microbial pathogen resulting in nosocomial acquired infections with significant morbidity and mortality. The mechanism by which nosocomial bacteria, like A. baumanii, attain multidrug resistance to antibiotics is of considerable interest. The aim in this study was to investigate the spread status of antibiotic resistance genes, such as multiple β-lactamase genes and aminoglycoside-modifying enzyme genes, from A. baumanii strains isolated from patients with lower respiratory tract infections (LRTIs). METHODS: Two thousand six hundred and ninety-eight sputum or the bronchoalveolar lavage samples from inpatients with LRTIs were collected in 21 hospitals in the mainland of China from November 2007 to February 2009. All samples were routinely inoculated. The isolated bacterial strains and their susceptibility were analyzed via VITEK-2 expert system. Several kinds of antibiotic resistant genes were further differentiated via polymerase chain reaction and sequencing methods. RESULTS: Totally, 39 A. baumanii strains were isolated from 2698 sputum or bronchoalveolar lavage samples. There was not only a high resistant rate of the isolated A. baumanii strains to ampicillin and first- and second-generation cephalosporins (94.87%, 100% and 97.44%, respectively), but also to the third-generation cephalosporins (ceftriaxone at 92.31%, ceftazidine at 51.28%) and imipenem (43.59%) as well. The lowest antibiotic resistance rate of 20.51% was found to amikacin. The OXA-23 gene was identified in 17 strains of A. baumanii, and the AmpC gene in 23 strains. The TEM-1 gene was carried in 15 strains. PER-1 and SHV-2 genes were detected in two different strains. Aminoglycoside-modifying enzyme gene aac-3-Ia was found in 23 strains, and the aac-6'-Ib gene in 19 strains. aac-3-Ia and aac-6'-Ib genes hibernated in three A. baumanii strains that showed no drug-resistant phenotype. CONCLUSIONS: A. baumanii can carry multiple drug-resistant genes at the same time and result in multi-drug resistance. Aminoglycoside-modifying enzyme genes could be hibernating in aminoglycoside sensitive strains without expressing their phenotype. | 2010 | 21034630 |