# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 1257 | 0 | 1.0000 | Antimicrobial Susceptibility Pattern in the Bacteria Isolated from Surgical Site Infection: Emphasis on Staphylococcus Aureus; Yasuj City, Southwest Iran. BACKGROUND: Surgical site infections (SSIs) in surgical wards remains the most common cause of postoperative complications and realistically is the third most common origin of healthcare-related conditions. Staphylococcus aureus is undoubtedly the most common bacteria causing SSIs. The current study aimed at investigating the antimicrobial susceptibility pattern in bacteria isolated from SSIs, evaluation of tetracycline resistance genes, and SCCmec typing in S. aureus isolates isolated from patients with SSIs from 2018 to 2019 in Yasuj, Kohgiluyeh, and Boyer-Ahmad Province, Iran. METHODS: This study diligently investigated 240 potential patients. Antimicrobial susceptibility testing was performed properly by the disk diffusion method. For the final confirmation of isolated bacteria, PCR was used. The presence of tet genes and SCCmec typing was carried out by multiplex PCR. RESULTS: The results showed that the most common isolated pathogens included S. aureus, E. coli, P. aeruginosa, Coagulase-negative Staphylococci, and K. pneumonia in 58.8%, 19.8%, 9.2%, 6.8% and 5.4% of cases, respectively. The majority of the Gram positive isolates were resistant against penicillin (86%) and Gram negative were resistant against ciprofloxacin (75.6%). In isolates of Staphylococcus aureus, the mecA gene was detected in 63.6% of isolates. The predominant SCCmec types were type III (59.1%) and type I (18.4%). The tetK and tetM genes were detected in 80.7% and 71.9% of the S. aureus isolates, respectively. There was a statistically significant difference between tet genes (tetK and tetM) from the viewpoint of resistance to tetracycline (p = 0.024). CONCLUSIONS: According to the results of the current study, it is recommended to administer vancomycin, amikacin, and imipenem in Yasuj to treat SSIs. | 2021 | 33616327 |
| 2376 | 1 | 0.9994 | Molecular characterization and antimicrobial susceptibility of methicillin-resistant staphylococcus aureus isolates from clinical samples and asymptomatic nasal carriers in Istanbul (Turkey). BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) has been a widespread problem in Turkish hospitals. AIMS: The aim of this study was to investigate the staphylococcal toxin genes of the clinical and nasal MRSA isolates, and their antibiotic resistance profiles. MATERIALS AND METHODS: Isolation of nasal and clinical bacteria was done following standard microbiological methods. The presence of antimicrobial resistance genes (mec A, pvl, tsst-1, and SEs genes) was determined using the real-time polymerase chain reaction (PCR) assay. RESULTS: Among nasal MRSA isolates, 66.7% were toxigenic. The distribution of genes was as follows: pvl 26.7%, tsst-1 3.3%, and SEs 36.7%. Therefore, the nasal MRSA isolates had a rate of 23.3% multidrug resistance (MDR) pattern to the non-beta-lactams antibiotics. All (100%) clinical MRSA isolates were found to be toxigenic. The distribution of genes was as follows; pvl 10%, tsst-1 6.7%, and SEs 100%. The clinical MRSA isolates had a rate of 60% MDR. CONCLUSIONS: Following detection of pvl, tsst-1, and SEs among nasal and clinical MRSA isolates, and the presence of high antimicrobial resistance, the spread of these strains may be an additional factor contributing to the emergence of community-acquired (CA)-MRSA and hospital-acquired (HA)-MRSA. This study is the first to determine the resistance to linezolid and tigecycline in both nasal and clinical MRSA isolates, for the first time in Turkey. All nasal and clinical MRSA isolates were uniformly susceptible to vancomycin and quinupristin-dalfopristin. Our findings show that MRSA infections in Turkey can be empirically treated with vancomycin and quinupristin-dalfopristin based on the lack of demonstrable resistance to these drugs. | 2021 | 34290175 |
| 1300 | 2 | 0.9994 | Genotypic and Phenotypic-Based Assessment of Antibiotic Resistance and Profile of Staphylococcal Cassette Chromosome mec in the Methicillin-Resistant Staphylococcus aureus Recovered from Raw Milk. BACKGROUND: Multidrug resistant methicillin-resistant Staphylococcus aureus (MRSA) bacteria are determined to be one of the chief causes of foodborne diseases around the world. PURPOSE: This research was done to assess the genotypic and phenotypic profiles of antibiotic resistance and distribution of Staphylococcus cassette chromosome mec (SCCmec) types amongst the MRSA bacteria recovered from raw milk. METHODS: Five-hundred and ninety raw milk samples were collected and examined. MRSA bacteria were recognized using susceptibility evaluation toward oxacillin and cefoxitin disks. Profile of antibiotic resistance genes and SCCmec types were determined using the PCR. Antibiotic resistance pattern of isolates was examined using the disk diffusion. RESULTS: Thirty-nine out of 590 raw milk samples (6.61%) were positive for S. aureus. Twenty-eight out of 39 (71.79%) bacteria were defined as MRSA bacteria. Raw buffalo (80%) milk samples had the maximum incidence of MRSA, while raw camel (33.33%) had the minimum. MRSA bacteria harbored the maximum incidence of resistance toward penicillin (100%), tetracycline (100%), erythromycin (82.14%), gentamicin (78.57%) and trimethoprim-sulfamethoxazole (78.57%). Incidence of resistance toward more than eight classes of antibiotic agents was 28.57%. The most frequently distinguished antibiotic resistance markers were blaZ (100%), tetK (85.71%), dfrA1 (71.42%), aacA-D (67.85%), ermA (50%) and gyrA (42.85%). SCCmec IVa (29.62%), V (25%), III (14.81%) and IVb (11.11%) were the most frequently distinguished types. CONCLUSION: Raw milk of dairy animals maybe sources of multidrug resistant MRSA which pose a hygienic threat concerning the consumption of raw milk in Iran. Nevertheless, further investigations are necessary to understand supplementary epidemiological features of MRSA in raw milk. | 2020 | 32099419 |
| 1276 | 3 | 0.9994 | Should we leave the paper currency? A microbiological examination. OBJECTIVE: Pathogens can be transmitted to banknotes due to the personal unhygienic habits. The aim of study was to find the possible pathogens on the banknotes circulating in the market and also to present their antibacterial resistance and their various virulence factors using genotypic and phenotypic methods. METHODS: A total of 150 samples of bank-notes were randomly collected between August 2017 and March 2018. VITEK systems were used for identification and antimicrobial susceptibility testing respectively. Antimicrobial resistance genes (mecA, van, extended-spectrum β-lactamase [ESBL] and carbapenemases) and staphyloccoccal virulence genes (staphyloccoccal enterotoxins [SEs], pvl, and tsst-1) were determined using with real-time PCR. RESULTS: Staphylococcus aureus, coagulase-negative staphylococci (CoNS), Enterococcus spp., Gram-negative enteric bacteria, non-fermentative Gram-negative bacteria and Candida spp. were detected 48%, 54.7%, 56%, 21.3%, 18.7%, and 4%, respectively. Methicillin-resistant S. aureus, vancomycin-resistant enterococci and ESBL producing Gram-negative were found 46.8%, 1.3%, and 28.7%, respectively. Pvl, tsst-1, and SEs genes were found in a 2.8/4.9%, 1.4/1.2%, and 100/ 87.8% of the S. aureus/CoNS strains, respectively. The sea gene was found the most common enterotoxigenic gene. blaTEM, blaSHV, blaCTX-M-2, blaCTX-M-1, blaKPC, and blaOXA-48 were found 55.8%, 46.5%, 41.2%, 18.6%, 18.6%, and 18.6%, respectively in Gram-negative strains. CONCLUSIONS: These results is very important to highlight hygienic status of paper currencies. This can be considered as an indication that banknotes may contribute to the spread of pathogens and antimicrobial resistance. Therefore, we may need to start using alternative products instead of banknotes. | 2020 | 32066229 |
| 2187 | 4 | 0.9994 | Multicentre investigation of pathogenic bacteria and antibiotic resistance genes in Chinese patients with acute exacerbation of chronic obstructive pulmonary disease. OBJECTIVE: A prospective observational study to investigate the distribution and antimicrobial resistance of pathogenic bacteria in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) in Beijing, China. METHODS: Patients with AECOPD were recruited from 11 general hospitals. Sputum specimens were cultured and bacteria identified. Antibiotic susceptibility was determined for each isolate, and presence of antibiotic resistance genes was evaluated using polymerase chain reaction. RESULTS: Pathogenic bacteria were isolated from 109/318 patients (34.28%); 124 isolates of 22 pathogenic bacterial species were identified, including Klebsiella pneumoniae (16.94%), Pseudomonas aeruginosa (16.94%), Acinetobacter baumannii (11.29%), Streptococcus pneumoniae (8.87%), and Staphylococcus aureus (7.26%). S. aureus was sensitive to tigecycline, teicoplanin, vancomycin and linezolid but resistant to penicillin and levofloxacin. K.pneumoniae, P. aeruginosa, A. baumannii and E. coli were susceptible to amikacin and cefoperazone. CONCLUSIONS: K. pneumoniae and P. aeruginosa are the most common pathogenic bacteria in AECOPD cases in Beijing, China. Our antibiotic resistance findings may be helpful in selecting antibiotic therapy. | 2015 | 26152913 |
| 2352 | 5 | 0.9994 | Phenotypic and Molecular Detection of Biofilm Formation in Methicillin-Resistant Staphylococcus Aureus Isolated from Different Clinical Sources in Erbil City. BACKGROUND: Staphylococcus aureus is an important causative pathogen. The production of biofilms is an important factor and makes these bacteria resistant to antimicrobial therapy. OBJECTIVES: the current study aimed to assess the prevalence of resistance to antibacterial agents and to evaluate the phenotypic and genotypic characterization of biofilm formation among S. aureus strains. METHODS: This study included 50 isolates of Methicillin-resistant S. aureus (MRSA) and Methicillin-Susceptible S. aureus (MSSA). S. aureus was identified by molecular and conventional methods, and antimicrobial resistance was tested with a disc diffusion method. The biofilm formation was performed through the Microtiter plate method. Strains were subjected to PCR to determine the presence of nuc, mecA, icaA, icaB, icaC, and icaD genes. RESULTS: Of the 50 S. aureus isolates, 32(64%) and 18(36%) were MRSA and MSSA, respectively. A large number of MRSA and MSSA isolates showed resistance to Penicillin and Azithromycin, and a lower number of MRSA and MSSA isolates showed resistance to Amikacin Gentamicin. None of the isolates was resistant to Vancomycin. The MRSA strains had significantly higher resistance against antibiotics than MSSA strains (P = 0.0154). All isolates (MRSA and MSSA) were able to produce biofilm with levels ranging from strong (31.25 %), (16.6%) to moderate (53.12%), (50%) to weak (15.6%), (33.3%) respectively. The MRSA strains had a significantly higher biofilm formation ability than the MSSA strains (P = 0.0079). The biofilm-encoding genes were detected among isolates with different frequencies. The majority of S. aureus isolates, 42 (84%), were positive for the icaA. The prevalence rates of the icaB, icaC and icaD genes were found to be 37 (74%), 40 (80%) and 41 (82%), respectively. CONCLUSIONS: The prevalence of biofilm encoding genes associated with multidrug resistance in S. aureus strains is high. Therefore, identifying epidemiology, molecular characteristics, and biofilm management of S. aureus infection would be helpful. | 2023 | 36908866 |
| 2377 | 6 | 0.9994 | Multidrug-resistant and enterotoxigenic methicillin-resistant Staphylococcus aureus isolated from raw milk of cows at small-scale production units. OBJECTIVE: Staphylococcus aureus (S. aureus) has evolved as one of the most significant bacteria causing food poisoning outbreaks worldwide. This study was carried out to investigate the prevalence, antibiotic sensitivity, virulence, and enterotoxin production of S. aureus in raw milk of cow from small-scale production units and house-raised animals in Damietta governorate, Egypt. MATERIAL AND METHODS: The samples were examined bacteriologically, and antimicrobial sensitivity testing was carried out. Moreover, isolates were characterized by the molecular detection of antimicrobial resistance, virulence, and enterotoxin genes. RESULTS: Out of 300 milk samples examined, S. aureus was isolated from 50 samples (16.7%). Antibiotic sensitivity testing revealed that isolates were resistant to β-lactams (32%), tetracycline (16%), and norfloxacin (16%); however, they showed considerable sensitivity to ceftaroline and amikacin (72%). Multidrug-resistance (MDR) has been observed in eight isolates (16%), with a MDR index (0.5) in all of them. Of the total S. aureus isolates obtained, methicillin-resistant S. aureus (MRSA) has been confirmed molecularly in 16/50 (32%) and was found to carry mecA and coa genes, while virulence genes; hlg (11/16, 68.75%) and tsst (6/16, 37.5%) were amplified at a lower percentage, and they showed a significant moderate negative correlation (r = -0.59, p-value > 0.05). Antibiotic resistance genes have been detected in resistant isolates relevant to their phenotypic resistance: blaZ (100%), tetK (50%), and norA (50%). Fifty percent of MRSA isolates carried the seb enterotoxin gene. CONCLUSION: High detection rate of MRSA and MDR isolates from milk necessitates the prompt implementation of efficient antimicrobial stewardship guidelines, especially at neglected small-scale production units. | 2022 | 35445112 |
| 1302 | 7 | 0.9993 | A survey of prevalence and phenotypic and genotypic assessment of antibiotic resistance in Staphylococcus aureus bacteria isolated from ready-to-eat food samples collected from Tehran Province, Iran. BACKGROUND: Resistant Staphylococcus aureus (S. aureus) bacteria are considered among the major causes of foodborne diseases. This survey aims to assess genotypic and phenotypic profiles of antibiotic resistance in S. aureus bacteria isolated from ready-to-eat food samples. METHODS: According to the previously reported prevalence of S. aureus in ready-to-eat food samples, a total of 415 ready-to-eat food samples were collected from Tehran province, Iran. S. aureus bacteria were identified using culture and biochemical tests. Besides, the phenotypic antibiotic resistance profile was determined by disk diffusion. In addition, the genotypic pattern of antibiotic resistance was determined using the PCR. RESULTS: A total of 64 out of 415 (15.42%) ready-to-eat food samples were contaminated with S. aureus. Grilled mushrooms and salad olivieh harbored the highest contamination rate of (30%), while salami samples harbored the lowest contamination rate of 3.33%. In addition, S. aureus bacteria harbored the highest prevalence of resistance to penicillin (85.93%), tetracycline (85.93%), gentamicin (73.43%), erythromycin (53.12%), trimethoprim-sulfamethoxazole (51.56%), and ciprofloxacin (50%). However, all isolates were resistant to at least four antibiotic agents. Accordingly, the prevalence of tetK (70.31%), blaZ (64.06%), aacA-D (57.81%), gyrA (50%), and ermA (39.06%) was higher than that of other detected antibiotic resistance genes. Besides, AacA-D + blaZ (48.43%), tetK + blaZ (46.87%), aacA-D + tetK (39.06%), aacA-D + gyrA (20.31%), and ermA + blaZ (20.31%) were the most frequently identified combined genotypic patterns of antibiotic resistance. CONCLUSION: Ready-to-eat food samples may be sources of resistant S. aureus, which pose a hygienic threat in case of their consumption. However, further investigations are required to identify additional epidemiological features of S. aureus in ready-to-eat foods. | 2021 | 34635183 |
| 2189 | 8 | 0.9993 | High prevalence of Panton-Valentine Leucocidin (PVL) toxin carrying MRSA and multidrug resistant gram negative bacteria in late onset neonatal sepsis indicate nosocomial spread in a Pakistani tertiary care hospital. BACKGROUND: Neonatal sepsis has high incidence with significant mortality and morbidity rates in Pakistan. We investigated common etiological patterns of neonatal sepsis at a tertiary care setup. METHODS: 90 pus and blood, gram negative and gram positive bacterial isolates were analyzed for virulence and antibiotic resistance gene profiling using PCR and disc diffusion methods. RESULTS: Staphylococcus aureus showed strong association with neonatal sepsis (43 %) followed by Citrobacter freundii (21 %), Pseudomonas aeruginosa (13 %), Escherichia coli (15 %) and Salmonella enterica (8 %). Molecular typing of E. coli isolates depicted high prevalence of the virulent F and B2 phylogroups, with 4 hypervirulent phylogroup G isolates. 76.9 % S. aureus isolates showed presence of Luk-PV, encoding for Panton-valentine leucocidin (PVL) toxin with majority also carrying MecA gene and classified as methicillin resistant S. aureus (MRSA). ecpA, papC, fimH and traT virulence genes were detected in E. coli and Salmonella isolates. 47 % Citrobacter freundii isolates carried the shiga like toxin SltII B. Antimicrobial resistance profiling depicted common resistance to cephalosporins, beta lactams and fluoroquinolones. CONCLUSION: Presence of PVL carrying MRSA and multidrug resistant gram negative bacteria, all isolated from late onset sepsis neonates indicate a predominant nosocomial transmission pattern which may complicate management of the disease in NICU setups. | 2023 | 36621204 |
| 2359 | 9 | 0.9993 | Virulence Factor Genes and Antimicrobial Susceptibility of Staphylococcus aureus Strains Isolated from Blood and Chronic Wounds. Staphylococcus aureus is one of the predominant bacteria isolated from skin and soft tissue infections and a common cause of bloodstream infections. The aim of this study was to compare the rate of resistance to various antimicrobial agents and virulence patterns in a total of 200 S. aureus strains isolated from patients with bacteremia and chronic wounds. Disk diffusion assay and in the case of vancomycin and teicoplanin-microdilution assay, were performed to study the antimicrobial susceptibility of the isolates. The prevalence of genes encoding six enterotoxins, two exfoliative toxins, the Panton-Valentine leukocidin and the toxic shock syndrome toxin was determined by PCR. Of the 100 blood strains tested, the highest percentage (85.0%, 31.0%, and 29.0%) were resistant to benzylpenicillin, erythromycin and clindamycin, respectively. Out of the 100 chronic wound strains, the highest percentage (86.0%, 32.0%, 31.0%, 31.0%, 30.0%, and 29.0%) were confirmed as resistant to benzylpenicillin, tobramycin, amikacin, norfloxacin, erythromycin, and clindamycin, respectively. A significantly higher prevalence of resistance to amikacin, gentamicin, and tobramycin was noted in strains obtained from chronic wounds. Moreover, a significant difference in the distribution of sea and sei genes was found. These genes were detected in 6.0%, 46.0% of blood strains and in 19.0%, and 61.0% of wound strains, respectively. Our results suggest that S. aureus strains obtained from chronic wounds seem to be more often resistant to antibiotics and harbor more virulence genes compared to strains isolated from blood. | 2021 | 34357963 |
| 2156 | 10 | 0.9993 | Antimicrobial resistance in urinary pathogens and culture-independent detection of trimethoprim resistance in urine from patients with urinary tract infection. BACKGROUND: Although urinary tract infections (UTIs) are extremely common, isolation of causative uropathogens is not always routinely performed, with antibiotics frequently prescribed empirically. This study determined the susceptibility of urinary isolates from two Health and Social Care Trusts (HSCTs) in Northern Ireland to a range of antibiotics commonly used in the treatment of UTIs. Furthermore, we determined if detection of trimethoprim resistance genes (dfrA) could be used as a potential biomarker for rapid detection of phenotypic trimethoprim resistance in urinary pathogens and from urine without culture. METHODS: Susceptibility of E. coli and Klebsiella spp. isolates (n = 124) to trimethoprim, amoxicillin, ceftazidime, ciprofloxacin, co-amoxiclav and nitrofurantoin in addition to susceptibility of Proteus mirabilis (n = 61) and Staphylococcus saprophyticus (n = 17) to trimethoprim was determined by ETEST® and interpreted according to EUCAST breakpoints. PCR was used to detect dfrA genes in bacterial isolates (n = 202) and urine samples(n = 94). RESULTS: Resistance to trimethoprim was observed in 37/124 (29.8%) E. coli and Klebsiella spp. isolates with an MIC(90) > 32 mg/L. DfrA genes were detected in 29/37 (78.4%) trimethoprim-resistant isolates. Detection of dfrA was highly sensitive (93.6%) and specific (91.4%) in predicting phenotypic trimethoprim resistance among E. coli and Klebsiella spp. isolates. The dfrA genes analysed were detected using a culture-independent PCR method in 16/94 (17%) urine samples. Phenotypic trimethoprim resistance was apparent in isolates cultured from 15/16 (94%) dfrA-positive urine samples. There was a significant association (P < 0.0001) between the presence of dfrA and trimethoprim resistance in urine samples containing Gram-negative bacteria (Sensitivity = 75%; Specificity = 96.9%; PPV = 93.8%; NPV = 86.1%). CONCLUSIONS: This study demonstrates that molecular detection of dfrA genes is a good indicator of trimethoprim resistance without the need for culture and susceptibility testing. | 2022 | 35610571 |
| 1258 | 11 | 0.9993 | Occurrence of antimicrobial resistance and antimicrobial resistance genes in methicillin-resistant Staphylococcus aureus isolated from healthy rabbits. BACKGROUND AND AIM: Methicillin-resistant globally, Staphylococcus aureus (MRSA) is a major cause of disease in both humans and animals. Several studies have documented the presence of MRSA in healthy and infected animals. However, there is less information on MRSA occurrence in exotic pets, especially healthy rabbits. This study aimed to look into the antimicrobial resistance profile, hidden antimicrobial-resistant genes in isolated bacteria, and to estimate prevalence of MRSA in healthy rabbits. MATERIALS AND METHODS: Two-hundreds and eighteen samples, including 42 eyes, 44 ears, 44 oral, 44 ventral thoracic, and 44 perineal swabs, were taken from 44 healthy rabbits that visited the Prasu-Arthorn Animal Hospital, in Nakornpathom, Thailand, from January 2015 to March 2016. The traditional methods of Gram stain, mannitol fermentation, hemolysis on blood agar, catalase test, and coagulase production were used to confirm the presence of Staphylococcus aureus in all specimens. All bacterial isolates were determined by antimicrobial susceptibility test by the disk diffusion method. The polymerase chain reaction was used to identify the antimicrobial-resistant genes (blaZ, mecA, aacA-aphD, msrA, tetK, gyrA, grlA, and dfrG) in isolates of MRSA with a cefoxitin-resistant phenotype. RESULTS: From 218 specimens, 185 S. aureus were isolated, with the majority of these being found in the oral cavity (29.73%) and ventral thoracic area (22.7%), respectively. Forty-seven (25.41%) MRSAs were found in S. aureus isolates, with the majority of these being found in the perineum (16, 34.04%) and ventral thoracic area (13, 27.66%) specimens. Among MRSAs, 29 (61.7%) isolates were multidrug-resistant (MDR) strains. Most of MRSA isolates were resistant to penicillin (100%), followed by ceftriaxone (44.68%) and azithromycin (44.68%). In addition, these bacteria contained the most drug-resistance genes, blaZ (47.83%), followed by gyrA (36.17%) and tetK (23.4%). CONCLUSION: This study revealed that MRSA could be found even in healthy rabbits. Some MRSAs strains were MDR-MRSA, which means that when an infection occurs, the available antibiotics were not effective in treating it. To prevent the spread of MDR-MRSA from pets to owners, it may be helpful to educate owners about effective prevention and hygiene measures. | 2022 | 36590129 |
| 1275 | 12 | 0.9993 | Analysis of the Frequency, Antibiotic Susceptibility, and Related Genes among Foodborne Pathogenic Bacteria Isolated from Hospital Refrigerators in Tehran, Iran. BACKGROUND: Hospital refrigerators as essential food storage can be important source of food contamination. We aimed to investigate the frequency and antibiotic susceptibility of the pathogenic bacteria in three hospital refrigerators in Tehran. METHODS: This study was performed on 254 samples, collected from 60 refrigerators of the various wards of three hospitals, A, B, and C, in Tehran, Iran from 2020 to 2021. Following isolation and identification of isolates, the antibiotic susceptibility pattern was determined. PCR-based assays were used to screen the presence of antibiotic resistance genes of resistant isolates. RESULTS: From 254 collected samples, 236 samples (92.9%) were contaminated. Most strains were isolated from refrigerators with poorly cleaned, temperatures above 8 °C in non-critical wards. Most bacteria belonging to Enterobacteriaceae (68.8%), followed by Staphylococcus (11.9%), and Enterococcus (10.6%), while the frequency of non-Enterobacteriaceae isolates was 8.9%. The highest antibiotic resistant bacteria were in extended spectrum beta-lactamase (ESBL) 9.7%, vancomycin-resistant enterococci (VRE) 5.3%, methicillin-resistant S. epidermidis (MRSE) 0.4%, and methicillin-resistant S. aureus (MRSA) 0.4%, respectively. The bla (OXA-48), bla (CTX), and bcla (TEM) genes were found only in 10% of Enterobacteriaceae isolates. The bla (OXA-51) gene was found in all non-Enterobacteriaceae isolates. The vanA and mecA genes were detected in antibiotic-resistant Enterococcus and Staphylococcus. CONCLUSION: Our findings suggests major concern about cross-contamination and the emergence of antibiotic-resistant isolates as a potential health threat with hospital refrigerators origin. More attention to hospital refrigerators cleaning is necessary to prevent foodborne diseases and nosocomial infections. | 2024 | 38919309 |
| 1301 | 13 | 0.9993 | Phenotypic and Genotypic Assessment of Antibiotic Resistance of Staphylococcus aureus Bacteria Isolated from Retail Meat. BACKGROUND: Resistant Staphylococcus aureus (S. aureus) bacteria are determined to be one of the main causes of foodborne diseases. PURPOSE: This survey was done to assess the genotypic and phenotypic profiles of antibiotic resistance of S. aureus bacteria isolated from retail meat. METHODS: Four-hundred and eighty-five retail meat samples were collected and examined. S. aureus bacteria were identified using culture and biochemical tests. The phenotypic profile of antibiotic resistance was examined using the disk diffusion method. The genotypic pattern of antibiotic resistance was determined using the polymerase chain reaction. RESULTS: Forty-eight out of 485 (9.89%) raw retail meat samples were contaminated with S. aureus. Raw retail buffalo meat (16%) had the highest incidence of S. aureus, while raw camel meat (4%) had the lowest. S. aureus bacteria exhibited the uppermost incidence of resistance toward tetracycline (79.16%), penicillin (72.91%), gentamicin (60.41%), and doxycycline (41.666%). The incidence of resistance toward chloramphenicol (8.33%), levofloxacin (22.91%), rifampin (22.91%), and azithromycin (25%) was lower than other examined antibiotics. The most routinely detected antibiotic resistance genes were blaZ (58.33%), tetK (52.08%), aacA-D (33.33%), and ermA (27.08%). Cat1 (4.16%), rpoB (10.41%), msrA (12.50%), grlA (12.50%), linA (14.58%), and dfrA1 (16.66%) had the lower incidence rate. CONCLUSION: Raw meat of animals may be sources of resistant S. aureus which pose a hygienic threat about the consumption of raw meat. Nevertheless, further investigations are essential to understand supplementary epidemiological features of S. aureus in retail meat. | 2020 | 32440171 |
| 1266 | 14 | 0.9993 | Characterization of methicillin-resistant coagulase-negative staphylococci in milk from cows with mastitis in Brazil. Staphylococci are one of the most prevalent microorganisms in bovine mastitis. Staphylococcus spp. are widespread in the environment, and can infect animals and humans as opportunistic pathogens. The objective of this study was to determine the frequency of methicillin-resistance (MR) among coagulase-negative staphylococci (CoNS) previously obtained from milk of mastitic cows in Brazil and to characterize the antimicrobial resistance phenotype/genotype and the SCCmec type of MRCoNS isolates. Identification of MRCoNS was based on both biochemical and molecular methods. Susceptibility testing for eleven antimicrobials was performed by disk-diffusion agar. Antimicrobial resistance genes and SCCmec were investigated by specific PCRs. Twenty-six MRCoNS were detected (20 % of total CoNS), obtained from 24 animals, and were identified as follows: S. epidermidis (7 isolates), S. chromogenes (7), S. warneri (6), S. hyicus (5) and S. simulans (1). All MRCoNS isolates carried mecA while the mecC gene was not detected in any CoNS. The SCCmec IVa was demonstrated in nine MRCoNS, while the remaining 17 isolates harbored non-typeable SCCmec cassettes. In addition to oxacillin and cefoxitin resistance, MRCoNS showed resistance to tetracycline (n = 7), streptomycin (n = 6), tobramycin (n = 6), and gentamicin (n = 4), and harbored the genes tet(K) (n = 7), str (n = 3), ant(4') (n = 6) and aac(6')-aph(2″) (n = 4), respectively. In addition, seven strains showed intermediate resistance to clindamycin and two to streptomycin, of which two harboured the lnu(B) and lsa(E) genes and two the aad(E) gene, respectively. One isolate presented intermediate erythromycin and clindamycin resistance and harbored an erm(C) gene with an uncommon 89-bp deletion rendering a premature stop codon. MRCoNS can be implicated in mastitis of cows and they constitute a reservoir of resistance genes that can be transferred to other pathogenic bacteria. | 2014 | 24817534 |
| 2157 | 15 | 0.9993 | Prevalence and antibiotic resistance pattern of bacteria isolated from urinary tract infections in Northern Iran. BACKGROUND: This study aimed to investigate the bacteria associated with urinary tract infection (UTI) and antibiotic susceptibility pattern of the isolates during 2013-2015 in Northern Iran. MATERIALS AND METHODS: Overall 3798 patients with clinical symptoms of UTI were subjected as samples, and they were cultured and pure isolated bacteria were identified using biochemical tests and subjected to antibiogram assessment using disc diffusion method. RESULTS: Totally, 568 (14.96%) from 3798 patients had positive UTI. Four hundred and ninety-seven (87.5%) from 568 isolated bacteria were resistant to at least one antibiotic. Escherichia coli, Staphylococcus spp., and Pseudomonas spp. were the most prevalent bacteria. Isolated bacteria indicated the highest antibiotic resistance to methicillin (76.06%) and ampicillin (89.29%) and also revealed the most sensitivity to imipenem (99.1%) and amikacin (91.57%). Statistical analysis of the resistance pattern trend during 3 years indicated the insignificant increase (P > 0.05) in antibiotic resistance of the isolates. CONCLUSION: The results of this study revealed a great concern for emerging UTI-related multidrug-resistant strains of bacteria causing UTI in Iran. | 2017 | 29026424 |
| 1279 | 16 | 0.9993 | Antibiotic resistance and virulence potentials of E. faecalis and E. faecium in hospital wastewater: a case study in Ardabil, Iran. Hospital wastewater can contaminate the environment with antibiotic-resistant and virulent bacteria. We analyzed wastewater samples from four hospitals in Ardabil province, Iran for Enterococcus faecium and Enterococcus faecalis using culture and molecular methods. We also performed antimicrobial susceptibility testing and polymerase chain reaction testing for resistance and virulence genes. Out of 141 enterococci isolates, 68.8% were E. faecium and 23.4% were E. faecalis. Ciprofloxacin and rifampicin showed the highest level of resistance against E. faecalis and E. faecium isolates at 65%. High-level gentamicin resistance (HLGR), high-level streptomycin resistance (HLSR), ampicillin, and vancomycin resistance were observed in 25, 5, 10, and 5.15% of E. faecium, and 15, 6, 15, and 3.03% of E. faecalis isolates, respectively. The ant(6')-Ia and ant(3')-Ia genes that were responsible for streptomycin resistance were observed in HLSR isolates and aph(3')-IIIa and aac(6') Ie-aph(2″)-Ia genes accounting for gentamicin resistance were detected in HLGR isolates. vanA was the predominant gene detected in vancomycin-resistant isolates. The majority of isolates were positive for gelE, asa1, esp, cylA, and hyl virulence genes. We found that drug-resistant and virulent E. faecalis and E. faecium isolates were prevalent in hospital wastewater. Proper treatment strategies are required to prevent their dissemination into the environment. | 2023 | 37756195 |
| 2188 | 17 | 0.9993 | Detection of Virulence Factors and Antibiotic Resistance Pattern of Clinical and Intensive Care Unit Environmental Isolates of Pseudomonas aeruginosa. BACKGROUND: Pseudomonas aeruginosa is a gram-negative non-glucose fermenting aerobic bacteria and an opportunistic pathogen in humans and animals. The present study was carried out to investigate the distribution of virulence factors and antibiotic resistance properties of P. aeruginosa isolated from patients and intensive care unit (ICU) environment. MATERIAL AND METHODS: A total of 116 P. aeruginosa isolated from patients and ICU environment were collected from Besat hospital in Hamadan, the West of Iran. P. aeruginosa isolates were analyzed based on the presence of the virulence factors encoding genes included exoA, exoS, exoU, and algD using polymerase chain reaction (PCR). Antimicrobial susceptibility test was performed using a disk diffusion method. RESULTS: The results showed the prevalence of exoA 33 (56.9%), exoS 21 (36.20%), exoU 37 (63.8%), and algD 35 (60.34%) genes in ICU environment P. aeruginosa strains and exo A 23 (39.25%), exoS 25 (43.1%), exoU 40(68.98%), and algD 25 (43.1%) genes in clinical isolates of P. aeruginosa. High resistance levels of the clinical and ICU environment isolate to ampicillinsulbactam (100%), were also observed. CONCLUSION: Our findings should raise awareness about antibiotic resistance in hospitalized patients in Iran. Clinicians should exercise caution in prescribing antibiotics, especially in cases of human infections. | 2020 | 31889501 |
| 2165 | 18 | 0.9993 | 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 |
| 1267 | 19 | 0.9992 | Detection and characterization of methicillin-resistant and susceptible coagulase-negative staphylococci in milk from cows with clinical mastitis in Tunisia. OBJECTIVES: This study investigated prevalence of methicillin-resistant (MR) and methicillin-susceptible (MS) coagulase-negative staphylococci (CNS) and the implicated mechanisms of resistance and virulence in milk of mastitis cows. In addition, the presence of SCCmec type was analyzed in MR Staphylococcus epidermidis (MRSE). RESULTS: Three hundred milk samples from cows with clinical mastitis were obtained from 30 dairy farms in different regions of Tunisia. Sixty-eight of the 300 tested samples contained CNS strains. Various CNS species were identified, with Staphylococcus xylosus being the most frequently found (40%) followed by Staphylococcus warneri (12%). The mecA gene was present in 14 of 20 MR-CNS isolates. All of them were lacking the mecC gene. The SCCmecIVa was identified in four MRSE isolates. Most of CNS isolates showed penicillin resistance (70.6%) and 58.3% of them carried the blaZ gene. MR-CNS isolates (n = 20) showed resistance to erythromycin, tetracycline and trimethoprim-sulfametoxazole harboring different resistance genes such us erm(B), erm(T), erm(C), mph(C) or msr(A), tet(K) and dfr(A). However, a lower percentage of resistance was observed among 48 MS-CNS isolates: erythromycin (8.3%), tetracycline (6.2%), streptomycin (6.2%), clindamycin (6.2%), and trimethoprim-sulfametoxazole (2%). The Inu(B) gene was detected in one Staphylococcus xylosus strain that showed clindamycin resistance. The virulence gene tsst-1 was observed in one MR-CNS strain. DISCUSSION: Coagulase-negative staphylococci containing a diversity of antimicrobial resistance genes are frequently detected in milk of mastitis cows. This fact emphasizes the importance of identifying CNS when an intramammary infection is present because of the potential risk of lateral transfer of resistant genes among staphylococcal species and other pathogenic bacteria. | 2018 | 30077662 |