|
|
|
 |
Search published articles |
 |
|
Showing 3 results for Alinezhad
Maryam Nazari, Nilofar Saeli, Mohsen Arzanlou, Saghar Jafari-Ramedani, Hafez Mirzanejad-Asl, Farzad Khademi, Aida Alinezhad,
Volume 24, Issue 1 (Spring 2024)
Abstract
Background: Antibiotic resistance represents a critical global concern within the medical community, posing significant challenges in the treatment of infections caused by drug-resistant pathogens. Over the years, broad-spectrum fluoroquinolones have been extensively used to treat infections caused by both Gram-positive and Gram-negative bacteria, including Pseudomonas aeruginosa. In this study, we decided to assess the prevalence of plasmid-mediated quinolone resistance mechanisms among clinical isolates of P. aeruginosa in Ardabil hospitals.
Methods: We analyzed a total of 200 clinical isolates of P. aeruginosa, collected between June 2019 and May 2023. The antibiotic resistance profiles of these strains against various fluoroquinolone antibiotics were determined using the disk diffusion method. Additionally, we investigated the presence of qnrA, qnrB, qnrC, qnrD, and qnrS genes through polymerase chain reaction (PCR) analysis. Furthermore, we assessed the expression levels of efflux pump genes and outer membrane porin genes using the quantitative reverse transcription PCR (qRT-PCR) in fluoroquinolone-resistant P. aeruginosa strains.
Results: Our findings revealed that 69% of P. aeruginosa strains were resistant to fluoroquinolones. The resistance rates for different fluoroquinolones were as follows: ciprofloxacin 55.5%, ofloxacin 62%, norfloxacin 53.5%, lomefloxacin 55.3%, and levofloxacin 55.5%. Notably, 78.9% of these strains exhibited multidrug resistance (MDR). Among the qnr genes, qnrB was the most prevalent (2.9%). No other qnr genes were identified. Interestingly, 75% of P. aeruginosa strains carrying the qnrB gene showed overexpression of efflux pump genes, while 100% exhibited down-regulation of the oprD gene.
Conclusion: Given the high prevalence of fluoroquinolone-resistant P. aeruginosa clinical isolates in Ardabil hospitals and the multifactorial nature of resistance, continuous monitoring of antibiotic resistance trends and understanding the underlying resistance mechanisms are crucial for selecting appropriate treatment strategies.
Saghar Jafari-Ramedani, Fereshteh Hasanpour, Alireza Mohammadnia, Farzad Khademi, Aida Alinezhad,
Volume 24, Issue 3 (Autumn 2024)
Abstract
Background: The Gram-negative pathogen Pseudomonas aeruginosa (P. aeruginosa) is a common cause of hospital-acquired infections. This bacterium is continuously increasing its resistance to commonly used antimicrobial drugs, posing significant challenges for clinical treatment. Therefore, this study aimed to investigate the trend of antibiotic resistance in P. aeruginosa from 2019 to 2023 in hospitals in Ardabil city.
Methods: This cross-sectional descriptive study utilized 200 clinical isolates of P. aeruginosa obtained from urine, respiratory, wound, blood, and cerebrospinal fluid samples of patients who visited Ardabil hospitals between June 2019 and May 2023. The sensitivity and resistance of P. aeruginosa isolates to antibiotics-including piperacillin, piperacillin / tazobactam, ceftazidime, cefepime, aztreonam, imipenem, meropenem, amikacin, tobramycin, netilmicin, ciprofloxacin, ofloxacin, norfloxacin, levofloxacin, and colistin-were assessed using the disk diffusion and agar dilution methods.
Results: Over a period of 4 years, the resistance of P. aeruginosa to various antibiotics was observed as follows: piperacillin 45.5%, piperacillin/tazobactam 31%, ceftazidime 44%, cefepime 46%, aztreonam 12%, imipenem 67.5%, meropenem 52%, amikacin 43%, tobramycin 45.5%, netilmicin 39.2%, ciprofloxacin 55.5%, ofloxacin 62%, norfloxacin 53.5%, levofloxacin 55.5%, and colistin 9%. It is worth mentioning that the trend of antibiotic resistance in P. aeruginosa to all tested antibiotics increased during the first and second years, decreased in the third year, and then experienced a significant increase again in the fourth year. Throughout this period, the emergence of multidrug-resistant (MDR) strains of P. aeruginosa has also been on the rise.
Conclusion: The present study confirmed that the overall trend of resistance to various antibiotics among P. aeruginosa strains isolated from patients in Ardabil is on the rise.
Faraz Malek Bagali, Aliasghar Rostamizad Kheljani, Leila Asadi, Farzad Khademi, Aida Alinezhad,
Volume 25, Issue 2 (Summer 2025)
Abstract
Background: Urinary tract infections (UTIs) are among the most common bacterial infections worldwide. Although these infections are usually treated with various antibiotics, the improper and excessive use of these drugs has played an important role in the emergence of antibiotic-resistant strains. This study aimed to investigate the frequency of bacterial pathogens isolated from UTI cases and their antibiotic resistance patterns in Imam Khomeini hospital, Ardabil.
Methods: In this cross-sectional study, a total of 202 culture-positive urine samples were collected from hospitalized and outpatients referred to Imam Khomeini hospital, Ardabil, from March 2024 to July 2024. The urine samples were cultured on blood agar and MacConkey agar media and then identified using Gram staining and standard biochemical tests. Antibiotic susceptibility testing was performed using the disk diffusion method according to the latest Clinical and Laboratory Standards Institute (CLSI) guidelines.
Results: A total of 7 bacterial species were identified, among which Escherichia coli (50.9%) and Klebsiella pneumoniae (22.7%) were recognized as the most common urinary pathogens. E. coli showed the highest resistance to ampicillin (89.3%) and cefazolin (67.9%), while K. pneumoniae exhibited complete resistance to ampicillin (100%) and considerable resistance to cefotaxime (60.8%). Staphylococcus aureus had the highest drug resistance against ciprofloxacin (72.7%) and penicillin (63.6%). Proteus mirabilis demonstrated complete resistance to nitrofurantoin (100%) and high resistance to ampicillin (75%). In addition, Pseudomonas aeruginosa showed complete resistance to nitrofurantoin and cefazolin (100%). Enterococcus faecalis displayed notable resistance to co-trimoxazole (68.4%) and ciprofloxacin (57.8%). Acinetobacter baumannii also showed high resistance to cephalosporins and fluoroquinolones, ranging from 60% to 100%. The highest rates of multidrug-resistant (MDR) isolates were observed in P. aeruginosa (100%), A. baumannii (90%), and K. pneumoniae (86.9%).
Conclusion: The results of this study showed that E. coli was the most common causative agent of urinary tract infections in Imam Khomeini hospital, Ardabil. Notably, the high level of antibiotic resistance among bacterial isolates, particularly MDR strains, highlights the necessity of continuous surveillance and rational use of antibiotics.
|
|
.png)
.png)
