جستجوی مقالات مرتبط با کلیدواژه « Antimicrobial resistance » در نشریات گروه « پزشکی »

Microbial biofilm is characterized by the irreversible attachment of planktonic cells to a surface and is usually associated with high antimicrobial resistance with worsening the wound healing. The objective of the study was to determine the prevalence of Staphylococcus aureus in diabetic foot ulcers (DFUs) of diabetic patients and to in- vestigate antibiotic susceptibility patterns of these isolates. In addition to screen biofilm forming ability of isolated S. aureus.

A total of 112 non-healing wound swabs of diabetic foot patients were collected and cultured on different culture media to identify and characterize 98 isolates. The S. aureus isolates were examined for their antibiotic susceptibility to different antimicrobial agents. Furthermore, S. aureus isolates were evaluated for their biofilm production capability using the Tissue Culture Plate Method (TPC). The level of icaA gene expression was determined by RT-PCR.

The results of this study showed that these non-healing wounds yield positive cultures, with an average of 1.67 or- ganisms per sample. The isolates showed highest resistance against oxacillin (95.2%) and lowest resistance against linezolid (3.7%). All isolates were biofilm producers and a significant association with the icaA gene expression level was recorded.

This study showed that S. aureus isolates have a great ability to produce biofilms that are associated with the chronicity of wounds in diabetic patients. Routine screening for biofilm formers in chronic wounds and their antibiotic sus- ceptibility testing will help in early treatment and prevent any other complications.

 Pantoea agglomerans is a Gram-negative rod that forms aggregates in liquid media. It is known for causing opportunistic infections in humans, especially in hospital settings and wounds from plant materials. The bacterium can lead to various infections like arthritis, endophthalmitis, and bacteremia, often from wooden splinters or plant thorns. Infections are diverse and affect immunocompromised individuals but respond well to antibiotics. P. agglomerans can be identified by its morphological characteristics and growth preferences in the lab. Resistance to Fosfomycin can aid in identification. Treatment typically involves antibiotics like imipenem and fluoroquinolones. Hospital-acquired infections from P. agglomerans have been linked to scenarios like endocarditis and septicemia. Selective culture media are crucial for isolating Pantoea species from clinical specimens. Regarding the treatment of infections induced by P. agglomerans, it is noteworthy that this bacterium generally exhibits susceptibility to a broad spectrum of antibiotics. Notably, these include but are not limited to imipenem, fluoroquinolones (e.g., ciprofloxacin and ofloxacin), aminoglycosides (e.g., amikacin, gentamicin, and tobramycin), broad-spectrum cephalosporins, and trimethoprim-sulfamethoxazole

Secondary bacterial and fungal infections are a significant concern in COVID-19 patients, particularly those critically ill and requiring intensive care. This retrospective study investigated the prevalence and spectrum of secondary infections among COVID-19 patients admitted to the intensive care unit (ICU) at a tertiary care hospital in Navi Mumbai. Additionally, we explored the association between secondary infections and patient comorbidities.

We performed a single-center, retrospective cohort study of 3234 COVID-19 patients admitted to a tertiary care hospital in Navi Mumbai, India, between August 2020 and August 2021. Microbiological data from various clinical specimens, including blood, sputum, bronchoalveolar lavage (BAL) fluid, urine, and tissue cultures, were retrospectively analyzed. Patient demographics and comorbidities were extracted from medical records. We employed descriptive statistics and Pearson's Chi-square test for data analysis to identify associations between secondary infections and patient characteristics.

Among the 3234 COVID-19 patients, 195 (6.02%) presented with clinical features suggestive of secondary infections. Microbiological analysis confirmed secondary infections in 98 patients (3.03%), with a culture positivity rate of 50.3%. Among bacterial isolates, Klebsiella pneumoniae was the most prevalent (43.28%), followed by Acinetobacter baumannii (25.37%). Aspergillus spp. emerged as the dominant fungal pathogen. Notably, Escherichia coli isolation was significantly associated with various specimen types (P < 0.001). However, no significant correlation was found between secondary infection rates and patient comorbidities.

Gram-negative bacteria, specifically K. pneumoniae and A. baumannii, were the primary pathogens responsible for secondary infections in our cohort of critically ill COVID-19 patients admitted to the ICU. These findings underscore the importance of ongoing surveillance and monitoring of secondary infection trends, including fungal pathogens, to inform and optimize management strategies in this high-risk population.

Pseudomonas aeruginosa is an important pathogen in healthcare settings that poses significant challenges due to its ability to rapidly develop antibiotic resistance. Its propensity to form biofilms and adapt to host defenses makes it even more difficult to treat, leading to prolonged and debilitating illnesses. So, it is vital to prioritize efforts to develop new strategies for treating infections caused by this pathogen. In the present work, morphological and biological characteristics of vB_PaeS_TUMS_P6 (P6), a lytic phage against P. aeruginosa, belonging to the genus Luzseptimavirus were fully described.

P. aeruginosa ATCC 27853 was used for propagation and biological characterization of P6. Its morphology was assessed using transmission electron microscopy (TEM). Adsorption rate assay, one-step growth curve analysis and time-kill experiment were analyzed. Host Range of P6, as well as pH and thermal stability were also determined.

The results showed that it was of classic podovirus morphology and had a short latent period. It could kill bacteria at multiplicity of infection as low as 0.01 and also infect some multidrug-resistant clinical isolates. Stability data suggested that P6 remained stable in various temperatures and pH levels, which is a beneficial characteristic for phage therapy in different situations.

This study presents promising data supporting the future use of P6 as a candidate for phage therapy.

This study explores the impact of Lucilia sericata maggots on the development and eradication of biofilms created by the pathogenic bacteria, Staphylococcus aureus and Pseudomonas aeruginosa.

We assessed the influence of Lucilia sericata maggot extract on the viability of planktonic bacteria, the formation and disruption of biofilms, bacterial metabolic activity. Also the effect of simultaneous ES-antibiotic treatment in biofilm elimination was investigated. Additionally, the expression levels of genes associated with biofilm formation, namely LasI, psLA, agrA, and icaD was studied.

The results showed that ES can reduce the viability of planktonic S. aureus, significantly. Furthermore, ES of larvae fed on S. aureus-infected meat displayed the most substantial inhibition of biofilm formation (62.11% and 75.04% inhibition for S. aureus and P. aeruginosa, respectively). A similar trend was observed in biofilm destruction, with values of 56.67% and 68.50% inhibition for S. aureus and P. aeruginosa, respectively. The simultaneous application of ES of larvae that fed on S. aureus-infected meat and the minimum inhibitory concentration (MIC) of gentamicin resulted in 100% inhibition of biofilm formation by S. aureus. Notably, the group treated with ES of larvae fed on S. aureus-infected meat exhibited the most significant reduction in metabolic activity, with values of 95.03% and 68.25% for S. aureus and P. aeruginosa, respectively. The expression of LAsI and pslA genes in P. aeruginosa and the expression of agrA and icaD genes in S. aureus has decreased

The findings of this study demonstrate that maggot extract has not only impacted the formation, but also eliminated the biofilms of S. aureus and P. aeruginosa.

Haemophilus influenzae and Moraxella catarrhalis are common pathogens in respiratory tract infections, causing some diseases like community-acquired pneumonia, acute sinusitis, and otitis media. Antimicrobial resistance in these pathogens occurs over the years. This systematic review aimed to investigate the antibiotic resistance pattern of these pathogens in Iran in the last 5 years.

All original articles related to the antimicrobial resistance of H. influenza and M. catarrhalis in Iran since 2018 were searched in English and Persian databases. The articles were screened primarily and secondary. After screening the articles (extracted blindly), conflicts were resolved, and the final data were reviewed.

This study included nine articles after primary and secondary screening steps, comprising 111 H. influenzae and 78 M. catarrhalis isolates. The lowest resistance of H. influenzae isolates was against levofloxacin (0.0%), cefotaxim (11.1%), and ceftriaxone (11.1%), while the highest resistance of these isolates was against tetracycline, co-trimoxazole, and ampicillin. M. catarrhalis isolates showed the highest resistance to penicillin (100%), cefazolin (87.5%), cefuroxime (84.4%), ampicillin (84.4%), and amoxicillin (81.2%). Co-trimoxazole resistance rates of M. catarrhalis isolates from adenoid tissue and pharynx were different. Resistance to fluoroquinolones was 0.0%; macrolides were the most effective antibiotics.

Fluoroquinolones and macrolides are the most effective antibiotics for M. catarrhalis, while fluoroquinolones and cefotaxime or ceftriaxone work best for H. influenzae. It is recommended to use fluoroquinolones and macrolides for managing outpatients and fluoroquinolones, macrolides, or ceftriaxone for managing inpatients. Prescription of β-lactams and/or co-trimoxazole is ineffective.

 Bacteria play a major role in urinary tract infections (UTIs); therefore, it is necessary to be aware of their regional prevalence and the causative pathogens for better prognosis and rapid treatment in clinical settings. This study aims to evaluate the prevalence of bacterial isolates involved in UTI samples and their antibiotics resistance pattern.

 In this cross-sectional study, bacterial infections from 4214 urine samples were analyzed from December 2016 to December 2018. After biochemical tests, disk diffusion susceptibility procedures were performed on all positive clinical cultures, according to CLSI guidelines. The obtained data were sorted and statistically analyzed by SPSS 26.

 Out of 3582 suspected UTIs samples, 2006 (56%) were females and 1576 (44%) males in the 0-99 years old age range and mainly consisting of middle-aged and elderly patients (62.2%). Escherichia coli (53.43%) and Staphylococcus epidermidis (15.99%) were the most frequent isolates. Among gram negative bacteria, nitrofurantoin and among gram- positive, vancomycin represented the lowest resistance rates at 25.27% and 26.74% respectively. Piperacillin showed the least efficacy with a resistance rate of 76.04%, followed by cefazolin with a 74.94% resistance rate.  In gram positive bacteria, vancomycin and gentamicin showed more promise with respective resistance rates of 19.34% and 27.34%. The highest resistance was associated with ampicillin (68.61%) and Trimethoprim/Sulfamethoxazole (66.06%).

 Alarming resistance rates were observed in ampicillin and piperacillin, which should be taken into account in therapy guidelines in this area. Prevalence of resistant strains can be avoided by developing appropriate healthcare policies and community awareness.

 The coronavirus disease 2019 (COVID-19) pandemic has been a global shock since its initial spread in 2019. Medically, patients with coronavirus disease, especially those with pneumonitis, face serious life-threatening risks and often require mechanical ventilation and intensive care. Ventilator-associated pneumonia (VAP) remains a significant concern for critical care providers. Recent reports have highlighted the susceptibility of patients with confirmed COVID-19 receiving mechanical ventilation to nosocomial pneumonia (NP).

 This study was a cross-sectional study conducted in the intensive care unit (ICU) at Imam Khomeini Hospital Complex (IKHC) in Tehran, Iran, within April 2020 to April 2021. The study focused on critically ill COVID-19 patients who required mechanical ventilation and met the criteria for VAP. Standard biochemical assays were used to identify pure colonies in patients’ sample cultures, and antimicrobial susceptibility tests were conducted to assess antimicrobial resistance profiles. The findings were analyzed statistically using SPSS software (version 23.0).

 Out of 93 endotracheal aspirate samples, 64 samples tested positive for bacteria. Among the 64 eligible patients with positive cultures, 42 (65.6%) and 22 (34.4%) patients were male and female, respectively, with a mean age of 60.56 ± 13.58 years. A total of 52 patients (81.25%) had underlying conditions, such as hypertension, diabetes, and kidney or heart diseases. According to the study results, the most common pathogens were extensively drug-resistant (XDR) Klebsiella pneumoniae (7%) and Acinetobacter baumannii (23%). Additionally, 80% of Klebsiella pneumoniae and 90% of Acinetobacter baumannii were observed to be multi-drug resistant (P < 0.05).

 The COVID-19 pandemic has posed significant risks to critically ill patients, often necessitating mechanical ventilation and intensive care. Furthermore, VAP remains a serious challenge in this context, with high rates of XDR K. pneumoniae and A. baumannii. Effective infection control measures and surveillance are critical to mitigating the risk of NP in these vulnerable patients.

Cognizant of the harsh chemical method of nanoparticles synthesis, researchers are shifting towards the green phyto-mediated synthetic approaches. We herein report the green synthesis of Ag NPs and Co3O4 NPs using silver nitrate solution and cobalt nitrate solution as precursors added to aqueous extract of Croton Macrostachyus leaf extract to evaluate their antibacterial activity. 

The Characterization of the biosynthesized NPs were carried out by using spectroscopic techniques as X-ray diffraction (XRD), UV-Vis spectroscopy, Fourier Transform Infrared (FTIR), and scanning electron microscopy (SEM).

The average crystallite size of Ag NPs was found to be 12.62 nm from the XRD data, indicating a cubic crystal structure whereas that of Co3O4 NPs was found to be 12.75 nm, indicating a cubic spinel crystal structure.  The energy band gap for Ag NPs and Co3O4 NPs were 3.38 eV, and 3.34 eV respectively. The SEM images showed non-homogeneity of particles distribution with irregular geometries attributable to their shape and size for Ag NPs whereas spherical as well as irregular geometries attributed to non-homogeneity of the particles for Co3O4 NPs. The FTIR identifies the functional groups of the bioactive molecules that were actively involved as stabilizing and capping agents to prevent agglomeration of Ag NPs and Co3O4 NPs. The agar-well diffusion method was employed to evaluate the antibacterial activities of the produced nanoparticles against gram-positive (S. aureus and E. faecalis) and gram-negative (E. coli, S. typhimrium) bacterial strains. 

The biosynthesized nanoparticles showed promising antibacterial activities with Ag NPs exhibiting the best inhibition activities towards all bacteria species.

Context: 

In recent years, antimicrobial resistance (AMR) has become a global public health threat. Health system decision-makers need valid and reliable situation analysis to better plan for mitigating this threat.

 This scoping review investigated the research gaps in AMR publications in Iran and provided an evidential base to support the identification of priority research to better address antibiotic resistance needs in Iran.

 A search of academic databases, including Scopus, Institute for Scientific Information (ISI), Web of Science, MEDLINE/PubMed, EMBASE, and Iranian Database of Medical Literature (IDML), was performed in February 2018. The identified studies evaluated the resistance or susceptibility of antibiotics against any bacteria in an Iranian population. Title, abstract, and full-text screening were conducted, and the included studies were accordingly analyzed with respect to the study protocol.

 From 37,769 identified studies, 1,718 studies met all inclusion criteria. These studies evaluated the susceptibility of 131 antibiotics to 82 types of bacteria by conducting 3,509 antibiotic resistance tests. Ofloxacin, ciprofloxacin, and gentamicin had the highest number of studies, samples, and tested bacteria. Regarding the characteristics of the studies, 306 studies had an insufficient explicit definition of study characteristics, 231 studies published their results more than three years after conducting them, and 803 studies (46.7%) were published in local journals.

 Considering the importance of the AMR crisis, this scoping review debates the low quality of reporting in AMR-related publications in Iran despite extensive research.

A new type of corona virus has caused Corona virus disease-19 and, subsequently, a global pandemic. All individuals are prone to the disease, so drastic measures were taken to prevent its spread. This study aimed to evaluate the impact of COVID-19 on the progression of the antimicrobial resistance rate by comparing two periods: before and during COVID-19.

We used a cross-sectional design to investigate the Antimicrobial Resistance (AMR) rate before (03/2019 to 03/2020) and during COVID-19 (03/2020 to 03/2021) in a University Hospital in Marrakech. The data were analyzed using SPSS Version 25.0.

Among the 7106 specimens, there was a significant increase in the multidrug-resistant bacterial from 27.38% to 35.87% during COVID-19 (p<0.001), particularly in blood culture, cerebrospinal fluid, catheter, and pus. However, there was a non-significant change in puncture fluid, expectoration, protected distal sampling, joint fluid, stool culture, and genital sampling. A decrease in Multidrug-resistant bacteria (MDRB) was observed only in cytobacteriological urine tests (p<0.05). According to species, there was an increase in extended-spectrum beta-lactamase-producing Enterobacteriaceae, carbapen- em-resistant Enterobacteriaceae, and methicillin-resistant Staphylococcus aureus.

In our study, it is particularly noticeable that the MDRB has increased. These results highlight the importance that the pandemic has not been able to slow the progression.

Drug-resistant hospital-acquired infections (HAIs) are a growing concern in modern medicine throughout the world. Klebsiella pneumoniae is one of the most prominent causative agents of multidrug-resistant nosocomial infections. It is also widely recognized for having a high resistance level to many antibiotic classes, particularly beta-lactams. Carbapenemase-producing K. pneumoniae has been identified as a major global cause of HAIs with adverse clinical outcomes. Therefore, it is of the utmost importance to have an in-depth understanding of the antimicrobial resistance (AMR) genetic determinants of this bacterium to stop the spread of highly resistant K. pneumoniae in healthcare facilities and the resulting patient morbidity and mortality.

This study aimed to investigate the AMR pattern of K. pneumoniae isolates obtained from intensive care units (ICUs), with a focus on extended-spectrum beta-lactamases (ESBLs) genes blaCTX-M, blaGES, and blaIMP.

A total of 105 K. pneumoniae isolates obtained from the sputum samples of ICU patients were identified and confirmed using standard microbiological tests and 16S rRNA polymerase chain reaction (PCR). The antibiotic susceptibility test was performed for all the isolates. The presence of ESBL genes was determined phenotypically and by PCR.

The highest level of resistance was observed against ceftazidime (100%), cefotaxime (99%), and imipenem (93.3%). Approximately 87.6% and 39% of the isolates were sensitive to colistin and gentamicin, respectively. Phenotypic ESBL production was observed in 16 isolates, and the prevalence of blaCTX-M was 86.7%. No blaGES and blaIMP genes were detected.

Periodic investigation of AMR-mediating genes is essential due to the high prevalence of ESBL genes in HAIs. The presence of other ESBL genes needs to be investigated for a more accurate understanding of the AMR status of K. pneumoniae in healthcare settings.

Due to emergence of antimicrobial-resistant healthcare associated infections (HAIs), the implementation of antimicrobial stewardship programs (AMSP) is the need of hour at institutional and national levels. We conducted an assessment of the current status of infrastructure, manpower, and education and training (E&T) in relation to Antimicrobial Stewardship (AMS) in the tertiary care hospitals of India.

Healthcare professionals from 30 tertiary care hospitals in North-western India (public & private) were invited to participate in online survey from Nov 2022 to Apr 2023 by sending a pre-designed questionnaire about the current existing antimicrobial stewardship (AMS) practices at their hospitals through email. The answers received on various parameters of AMS were analyzed using descriptive statistics.

72 healthcare professionals from 30 hospitals responded to the survey. 63% of the respondents had received education and training (E&T) on AMS during undergraduate or postgraduate training. 65% had not received any E&T at induction to the hospital. The positive responses were 36%, 47% and 33% for leadership support, accountability and availability of drug expertise in form of pharmacologist/pharmacist respectively. A policy to support optimal antibiotic use was present in 25% of respondents. Broad interventions to improve antibiotic use were scored as 28%, 7% and 6% for antibiotic time out, pre-authorization and prospective audit with feedback respectively.

The findings reveal the enablers and barriers to implementation of antimicrobial stewardship and highlighted the need for establishing a framework for stricter implementation and monitoring of antimicrobial stewardship in Indian tertiary care hospitals. Few key areas which require immediate attention are: need for government level endorsement and leadership support of antimicrobial stewardship (AMS) activities; lack of AMS programs in hospitals; and lack of undergraduate/ postgraduate/at induction education and training in AMS for staff.

Urinary tract infection (UTI) is common after pediatric renal transplantation, and the emergence of multidrug-resistant (MDR) bacteria causing UTI is a therapeutic challenge in this regard. The main purpose of this study was to determine the UTI frequency, its etiologic agents, and the antibiotic susceptibility pattern in the first year following renal transplantation in Iranian pediatric recipients. 

In a retrospective cohort study, all of the 81 children who had undergone renal transplantation in Hazrat Rasoul Akram Hospital between 2012 and 2017 were enrolled. Confirmed episodes of UTI during the first year following renal transplantation were analyzed. The pattern of antibiotic resistance was determined for the causative agents of UTI. The data were analyzed using the IBM SPSS Statistics software (version 20). and the P < 0.05 was considered significant. 

Totally, from 81 enrolled cases, 37(44.7%) cases were in the age group of 11-15 years. Overall, 19, 10, and 3 UTI episodes had occurred in the first month, from the first to sixth month, and between the sixth month and one year after transplantation, respectively. The four most common isolated bacteria were Escherichia coli (E. coli; 31.2%), Pseudomonas aeruginosa (P. aeruginosa; 25%), Enterococci (21.9%) and Klebsiella pneumoniae (K. pneumoniae; 12.5%). The highest rate of resistance was reported to trimethoprim/sulfamethoxazole (TMP/SMX), cephalosporins, and fluoroquinolones among gram-negative bacteria. However, none of the Enterococci isolates were resistant to linezolid and nitrofurantoin.

Resistance to antibiotics is increasing among the pathogens causing UTI in pediatric renal transplanted cases. It is suggested to stop the administration of TMP/SMX and third-generation cephalosporins for empiric treatment of UTI in Iranian pediatric renal transplant recipients. Ciprofloxacin might be administered cautiously secondary to the increasing rate of antibiotic resistance in this group.

 Urinary tract infection (UTI) is One of the most prevalent infectious diseases in human, where the study aimed to identify the most uropathogen that caused UTIs ,and its the antimicrobial resistance pattern.

  the samples were collected from January and December 2021 using a standard data collection form, where  the patient outcome records were mined for information on the patients' gender, age, isolated organisms, and susceptibility test results, then statistical analysis was done.

 266 from 463 samples  were identified as S. aureus 14.3% , in addition, the antibacterial resistance rats showed that the highest resistance was against ampicillin/Sulbactam, ceftazidine, and meropenem 79%, while, the lowest was against ciprofloxacin 40%.

The study showed that S. aureus is the primary cause of UTIs in Derna city, as a result of consuming antibiotics randomly, which resulted in an increase in spread and resistance of S. aureus.

The ocular microbiota, which includes both commensal and pathogenic microorganisms, is constantly exposed to the ocular surface. It has recently become increasingly acknowledged that the ocular microbiota plays a vital role in maintaining eye health and that interventions, including the use of drugs on the surface of the eye, can potentially disrupt the equilibrium of microorganisms within the eye. One area that has received relatively little attention in the literature is the potential effect of these interventions on the microbiota within the vitreous. The aim of this study is to investigate the effect of intravitreal injections on the ocular microbiota of patients, specifically examining changes in the composition and relative abundance of ocular microbes as a result of this treatment.

In this study, two groups of patients were analyzed. Group A included 19 individuals who had not received intravitreal injections or undergone perioperative management. Group B, on the other hand, consisted of 22 patients who had received one, two, or more two treatments. The microbial samples collected from the ocular surface of these patients were subjected to 16S rRNA sequencing using the HiSeq 2500 platform. Further analysis of the alpha/beta diversity and clustering of operating taxonomic units (OTUs) was carried out.

Our results show a significant difference in beta diversity was observed between group A (15 patients without intravitreal injections or perioperative management) and group B (patients with at least one, twice, or more than twice treatment) with a P value of 0.014. It was found that both the composition and relative abundance of cells were impacted by perioperative management in the lead-up to intravitreal injection. Additionally, a greater diversity of Gram-negative bacteria was observed and the most significant groups of microbiotas were found to be phyla and genera.

In conclusion, our study found that perioperative management has a significant impact on the ocular microbiota, altering its composition and disrupting its balance. Therefore, it is important for clinicians to carefully consider perioperative management prior to administering intravitreal injections.