Showing 7 results for Antibiotic Resistance
Ali Hashemi, Saeed Shams, Mohammad Barati, Azizeh Samedani,
Volume 14, Issue 4 (9-2011)
Abstract
Background: Pseudomonas aeruginosa is one of the most important causes of nosocomial infection which due to extended spectrum-beta lactamases (ESBLs) and metallo-beta lactamase (MBL) producing strains is resistant to a wide range of antibiotics. The aim of this study was to detect ESBL and MBL producing P.aeruginosa isolated from patients and investigate the effects of methanol extracts of Zataria multiflora, Myrtus communis, and Peganum harmala on them.
Materials and Methods: In this experimental study, samples were obtained from 245 patients, referring to Shafa Hospital, Kerman, Iran. ESBLs producing strains were detected by double disk synergy test and phenotypic confirmatory test. In addition, E-test strips were used for MBL detection. P.aeruginosa MIC was determined for cefotaxime, ceftazidime, azteronam, imipenem, and meropenem. Methanol extracts of Zataria multiflora, Peganum harmala, and Myrtus communis plants were prepared by Agar perculation method.
Results: Out of 245 patients referring to the burn unit, 120 P.aeruginosa isolates were detected from which 41 contained ESBL but they lacked MBL. 60% of isolates were resistant to cefotaxime, 66% to ceftazidime, 42% to azteronam, 3% to imipenem, and 5% to meropenem. Among the extracts, Zataria multiflora had the highest antibacterial effect on standard strains of P.aeruginosa in comparison with Peganum harmala and Myrtus communis.
Conclusion: The prevalence of ESBL producing P.aeruginosa strains is high. In addition, noticing their high antibiotic resistance, utilization of herbs, such as Zataria multiflora may be considered an appropriate alternative for treatment however, more investigations are needed.
Adeleh Hoseinizadeh, Hamid Abtahi, Mana Shojapour, Majid Akbari, Razieh Nazari, Masoomeh Sofian,
Volume 15, Issue 6 (11-2012)
Abstract
Background: Enterococcus is known as an important pathogen in Iran like all around the world. The increasing use of vancomycin makes vancomycin-resistant enterococci (VRE) an important nosocomial pathogen. Vancomycin in combination with an aminoglycoside can provide effective treatment for severe enterococcus infections, while resistance to vancomycin antibiotic is increasing in enterococci. In this study, the pattern of antibiotic resistance and prevalence of vancomycin resistance enterococci have been explored. Materials and Methods: In this experimental study, after isolating and identifying 150 strains of enterococci from clinical specimens, the antibiotic resistance pattern of these strains to erythromycin, teicoplanin, vancomycin, ciprofloxacin, tetracycline, gentamicin, co-trimoxazole and linezolid was examined. The MIC test by using micro dilution broth method was performed for the vancomycin resistance enterococci specimens with the vancomycin and teicoplanin antibiotics. Results: Antibiotic susceptibility test showed 14% and 5.3% of the samples were resistant to vancomycin and teicoplanin respectively. Resistant to erythromycin, co-trimoxazole, ciprofloxacin, tetracycline, linezolid and gentamicin were 64, 40, 38.6, 6.6, 0, 38.76 percent respectively. Fourteen samples had high resistance to vancomycin which MIC were ≥ 256 µg/ml. Conclusion: Based on the results of present study, there are vancomycin-resistant enterococci in Arak as well as other parts of the world. The percentage of vancomycin resistance enterococci is high in Arak and appropriate treatment of infections caused by enterococcus is essential
Mohsen Rezazadeh, Rasoul Yousefi Mashouf, Hossein Sarmadyan, Ehsanollah Ghaznavi-Rad,
Volume 16, Issue 2 (5-2013)
Abstract
Background: Staphylococcus aureus is considered a common pathogenic factor in infections. Increase in infections caused by this bacterium in developing countries has led to many problems. The aim of this study is to identify the antibiotic patterns of methicillin-resistant Staphylococcus aureus isolated from patients in the central hospital of Arak.
Materials and Methods: In this descriptive cross-sectional study, a total of 100 samples were isolated from hospital patients during one year. The isolates sensitivity to cefoxitin and oxacilin disks were evaluated through disk diffusion. Using polymerase chain reaction (PCR), the isolates were tested for the presence of mecA gene. Finally, antibacterial resistance patterns of the isolates to 13 antibiotics were determined.
Results: In this study, 80 samples in a total of 100 isolates of Staphylococcus aureus were methicillin-resistant. Evaluation and assessment of antibiotic resistance showed the greatest resistance to penicillin (100%), tetracycline (88.50%), levofloxacin (85.70%), and ciprofloxacin (85.70%), respectively, while the lowest levels of resistance were observed to antibiotics chloramphenicol (5.70%), netilmicin (5.70%), and mupirocin (0%), respectively.
Conclusion: This study showed increased resistance to different antibiotics in Staphylococcus aureus that is a serious warning to the treatment of infections caused by this bacterium in the region. Therefore, in order to prevent increased resistance to other antibiotics, it is essential to withhold prescriptions and unessential use of available antibiotics.
Seyyed Sajjad Khorramrooz, Farzaneh Gharibpour, Najmeh Parhizgari, Mahboobeh Yazdanpanah, Reza Mohammadi , Nasim Rahbari,
Volume 18, Issue 3 (6-2015)
Abstract
Background: Pseudomonas aeruginosa is one of the major etiologic agents of nosocomial infection among burn patients that has high resistance to antibiotics. Integrons can extend antibiotic resistance genes among bacteria. The aim of this study was to investigate the antibiotic resistance pattern and the prevalence of integron among P. aeruginosa isolates.
Materials and Methods: In this cross-sectional study, a total of 73 P. aeruginosa isolated from burn wound infections among hospitalized patients in Ahvaz Taleghani hospital. Antibiotic resistance pattern of these bacteria was investigated to 9 antibiotics by Disk Agar Diffusion method. Polymerase chain reaction (PCR) method was used to investigate the prevalence of class 1, 2 and 3 integrons. The data were analyzed by Chi-square test. A P-value of <0.05 was considered as a statistical significance level.
Results: The most antibiotic resistance level was seen against ofloxacin (94.5%), aztreonam (94.5%), and ceftazidime (93.6%). Fifteen isolates of P. aeruginosa were resistance to all of the antibiotics. The study of molecular results showed that class 1 integron was detected in 35.6% of isolates, while none of them harbored class 2 and 3 integron.
Conclusion: The rates of antibiotic resistance in pseudomonas aeruginosa to antibiotics such as ceftazidime, oflaxacin, aztreonam, cefepime, and ceftriaxone is very high. Although, class 1 integron were detected in 35.6% of isolates, there was no statistically significant differences between the presence of integron and resistance to a specific antibiotic, that it shows the role of the other antibiotic resistance mechanisms among pseudomonas aeruginosa.
Sare Karimi, Azam Haddadi, Parvin Torabzadeh,
Volume 21, Issue 2 (5-2018)
Abstract
Abstract
Background: In recent years, increasingly antibiotic resistance problem among Klebsiella isolates and side effects of antibiotics overuse have made researchers to study the antimicrobial activity of medicinal plants. The aim of this study was to study the inhibitory effect of ethanolic and aqueous extract of Vaccinium arctostaphylos on ESBLs producing Klebsiella strains.
Materials and Methods: Among 143 isolates of Klebsiella collected from some hospitals and clinical laboratories in Karaj, ESBLs producer were screened by phenotypic confirmatory test (PCT). One of them was identified based on 16S rRNA gene sequencing. MIC and MBC of ethanol and aqueous extracts of Vaccinium arctostaphylos were determined using microdilution method on selected ESBLs producing Klebsiella strains.
Results: Resistance to ceftazidime, ceftriaxon and cefotaxime was observed in 14.7% of the isolates. 32 isolates (22%) were detected as ESBL producers. Results of MIC and MBC tests showed that ethanolic and aqueous extract of Vaccinium arctostaphylos have inhibitory effect on ESBLs producing Klebsiella strains,
Conclusion: The presence of antibacterial activity could be confirmed in most plant species used in traditional medicine in Iran and we should focus on combining traditional medicines and modern drugs.
Behnoush Sadat Khalili, Javad Hamedi, Setareh Haghighat,
Volume 21, Issue 7 (2-2019)
Abstract
Background and Aim: The widespread use of antibiotics has been led to increased emergence of antibiotic resistant bacteria and high mortality and morbidity rates due to infectious diseases. Pseudomonas aeruginosa is one of the most important causes of nosocomial infections, which shows high resistance to a wide range of antibiotics. So, finding new and effective antimicrobial compounds in order to overcome antibiotic resistant infectious diseases is so critical. Screening of native actinobacteria can be an effective strategy to find novel antimicrobial compounds. The aim of current study was isolation, screening and identification of rare actinobacteria to find the strains which produce antimicrobial compounds against P. aeruginosa.
Material and Methods: Thirty samples of water and sediments were collected from Persian Gulf and Oman Sea and used for isolation of actinobacterial strains. After isolation of actinobacteria, their metabolites were extracted and their anti-P. aeruginosa activities were investigated. Minimum inhibitory concentration (MIC) of the most efficient extract was determined using broth microdilution method. Finally, the most efficient strain was identified.
Ethical Considerations: In this study, all principles of biosafety and bioethics have been considered.
Findngs: Fifty actinobacteria were isolated from water and sediments. Five isolates had considerable antimicrobial activity. MIC value of the most efficient extract against P. aeruginosa was 100 µg/ml. Molecular analysis of 16SrRNA showed that the most effective fermentation broth extract belongs to Micromonospora and has 99.8% similarity to M. chalcea.
Conclusion: The current study revealed that the water of southern Iran and their sediments are promising sources of potent rare Actinobacteria in the production of antimicrobial compounds against P. aeruginosa. |
Hiva Saki, Azam Haddadi, Mahmoud Shavandi,
Volume 21, Issue 7 (2-2019)
Abstract
Background and Aim: In recent years, Multidrug resistance has been increasing among Klebsiella isolates. The aim of this study was to survey existence of integrons and its relation with antibiotic resistance among clinical isolates of Klebsiella.
Materials and Methods: From Jun 2015 to May 2016, 129 Klebsiella isolates collected from Karaj hospitals and laboratories. Statistical population included 80.6% female and 19.4% male. Antimicrobial susceptibility was performed using Kirby-Bauer disk diffusion and ESBLs producer were screened. Integrons were detected using PCR.
Ethical Considerations: This study with research ethics code IR.IAU.K.REC.1396.16 has been approved by research ethics committee at Islamic Azad University of Karaj, Iran.
Findings: The highest and lowest percentage of sensivity were found to ofloxacin (89.1%) and amoxcicillin (6.2%), respectively. 82.9% of isolates were resistant to more than two antibiotics from different classes. Among 129 isolates, 19.3% of the isolates harbour integrons. Frequencies of MDR among integron-positive isolates were 100%. Also, 71.3% and 28.7% of isolates were ESBLs positive and negative respectively.
Conclusion: Results showed integron elements were prevalent among MDR isolates. Integron-associated resistance genes can be served as reservoirs of multi drug resistance within clinical isolates and presence of integron can be used as a marker to identify MDR isolates. Prevalence of ESBLs among clinical isolates of Klebsiella showed that antibiotics like ampicillin or amoxicillin-clavulanic acid are not effecvtive anymore in treatment of UTIs.
