Xiuhong Zhang, Sihui Cai, C. Chang, Qiuhui Wang, Weizhen Qiao
Introduction: Fulminant myocarditis is a life-threatening disease among young patients. Pseudomonas aeruginosa is distributed in nature and is often spread as an opportunistic pathogen to cause hospital-acquired infections in patients with underlying diseases and low immunity. Case Presentation: This report presented a case of a 28-year-old woman with fulminant myocarditis followed by P. aeruginosa infection. After hospitalization, she received veno-arterial extracorporeal membrane oxygenation (ECMO) and continuous renal replacement treatment (CRRT). Initially, piperacillin sodium tazobactam combined with amikacin was used for anti-infection therapy, which had a poor clinical effect. Subsequently, it was recommended to use ceftazidime-avibactam and amikacin for treatment. Finally, the infection index of the patient returned to normal. Conclusions: It is necessary to select correct and effective drugs according to etiology, considering the influence of ECMO and CRRT on the patient’s antimicrobial pharmacokinetics/pharmacodynamics (PK/PD). This case could provide a reference for safe and rational drug use in clinical practice.
{"title":"Combination Therapy with Ceftazidime-Avibactam and Amikacin for Multidrug-Resistant Pseudomonas aeruginosa Infection with Fulminant Myocarditis in a Younger Patient: A Case Report and Literature Review","authors":"Xiuhong Zhang, Sihui Cai, C. Chang, Qiuhui Wang, Weizhen Qiao","doi":"10.5812/jjm-136894","DOIUrl":"https://doi.org/10.5812/jjm-136894","url":null,"abstract":"Introduction: Fulminant myocarditis is a life-threatening disease among young patients. Pseudomonas aeruginosa is distributed in nature and is often spread as an opportunistic pathogen to cause hospital-acquired infections in patients with underlying diseases and low immunity. Case Presentation: This report presented a case of a 28-year-old woman with fulminant myocarditis followed by P. aeruginosa infection. After hospitalization, she received veno-arterial extracorporeal membrane oxygenation (ECMO) and continuous renal replacement treatment (CRRT). Initially, piperacillin sodium tazobactam combined with amikacin was used for anti-infection therapy, which had a poor clinical effect. Subsequently, it was recommended to use ceftazidime-avibactam and amikacin for treatment. Finally, the infection index of the patient returned to normal. Conclusions: It is necessary to select correct and effective drugs according to etiology, considering the influence of ECMO and CRRT on the patient’s antimicrobial pharmacokinetics/pharmacodynamics (PK/PD). This case could provide a reference for safe and rational drug use in clinical practice.","PeriodicalId":17803,"journal":{"name":"Jundishapur Journal of Microbiology","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45967007","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Seyyed Mohammad Hassan Aletayeb, M. Dehdashtian, A. Malakian, M. Aramesh, L. Kouti, Fateme Aletayeb
Background: One of the leading causes of neonatal mortality in low- and middle-income countries (LMICs) is neonatal sepsis caused by carbapenem-resistant gram-negative bacteria. Objectives: This study aimed to determine the frequency, bacterial profile, and outcome of carbapenem-resistant Gram-negative neonatal sepsis in southwest Iran. Methods: This 15-month retrospective cross-sectional descriptive study was conducted at a level 3 referral training hospital. The study included all neonates hospitalized from birth who had positive blood cultures for Gram-negative bacteria. Patients were divided into carbapenem-resistant and carbapenem-sensitive groups. Results: During the study, Gram-negative bacteria were isolated from the blood cultures of 113 neonates. Positive Gram-negative bacteria blood cultures and carbapenem-resistant cases were 2.38% and 1.52%, respectively. In these cases, 66 (58.4%) of the infants were males, 100 (88.4%) were preterm, and 74 (65.4%) required mechanical ventilation within the first three days of life. The study found 45 (39.8%) infants with early-onset sepsis. Acinetobacter was the most common isolated organism, while Enterobacter had the lowest isolation rate. Carbapenem resistance was discovered in 72 (63.7%) positive blood cultures. Acinetobacter had the highest prevalence of carbapenem resistance, while Pseudomonas had the lowest. Mortality rates in infants infected with carbapenem resistance bacteria (CRB) were 89.3% compared to 10.7% in those infected with carbapenem-sensitive bacteria (CSB). Conclusions: The frequency of carbapenem-resistant Gram-negative sepsis in our ward was 1.52 percent of all admissions, and Acinetobacter bacteria was the most common cause of this type of neonatal sepsis. Infants infected with CRB had a higher mortality rate than those infected with CSB, 89.3% versus 10.7%.
{"title":"Frequency, Bacteriological Profile, and Outcome of Neonatal Sepsis with Carbapenem-Resistant Gram-Negative Bacteria at the Tertiary Neonatal Intensive Care Unit, Ahvaz, Iran","authors":"Seyyed Mohammad Hassan Aletayeb, M. Dehdashtian, A. Malakian, M. Aramesh, L. Kouti, Fateme Aletayeb","doi":"10.5812/jjm-134278","DOIUrl":"https://doi.org/10.5812/jjm-134278","url":null,"abstract":"Background: One of the leading causes of neonatal mortality in low- and middle-income countries (LMICs) is neonatal sepsis caused by carbapenem-resistant gram-negative bacteria. Objectives: This study aimed to determine the frequency, bacterial profile, and outcome of carbapenem-resistant Gram-negative neonatal sepsis in southwest Iran. Methods: This 15-month retrospective cross-sectional descriptive study was conducted at a level 3 referral training hospital. The study included all neonates hospitalized from birth who had positive blood cultures for Gram-negative bacteria. Patients were divided into carbapenem-resistant and carbapenem-sensitive groups. Results: During the study, Gram-negative bacteria were isolated from the blood cultures of 113 neonates. Positive Gram-negative bacteria blood cultures and carbapenem-resistant cases were 2.38% and 1.52%, respectively. In these cases, 66 (58.4%) of the infants were males, 100 (88.4%) were preterm, and 74 (65.4%) required mechanical ventilation within the first three days of life. The study found 45 (39.8%) infants with early-onset sepsis. Acinetobacter was the most common isolated organism, while Enterobacter had the lowest isolation rate. Carbapenem resistance was discovered in 72 (63.7%) positive blood cultures. Acinetobacter had the highest prevalence of carbapenem resistance, while Pseudomonas had the lowest. Mortality rates in infants infected with carbapenem resistance bacteria (CRB) were 89.3% compared to 10.7% in those infected with carbapenem-sensitive bacteria (CSB). Conclusions: The frequency of carbapenem-resistant Gram-negative sepsis in our ward was 1.52 percent of all admissions, and Acinetobacter bacteria was the most common cause of this type of neonatal sepsis. Infants infected with CRB had a higher mortality rate than those infected with CSB, 89.3% versus 10.7%.","PeriodicalId":17803,"journal":{"name":"Jundishapur Journal of Microbiology","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46809742","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. Besharati, Hatef Ajoudanifar, H. Ghasemzadeh-moghaddam, A. Azimian
Background: In the COVID-19 era, co-infections can lead to an increase in morbidity and mortality. Normal flora bacteria can transfer to the pulmonary tract and create bacterial co-infections. The nasal cavity is one of the main areas housing normal flora in the human body. Objectives: In this study, we evaluated the prevalence and antibiotic resistance of gram-positive cocci in the pre– and post–COVID-19 eras among health care workers. Methods: We assessed 376 nasal swabs from the pre–COVID-19 era and 376 from the post–COVID-19 era. Conventional and molecular methods were used to identify bacterial types and evaluate antimicrobial resistance. Results: The most common gram-positive cocci in the pre–COVID-19 samples were Staphylococcus aureus, S. epidermidis, S. capitis, S. hominis, S. haemolyticus, Streptococcus pneumoniae, and Enterococcus faecalis. In the post–COVID-19 samples, the most common gram-positive cocci were S. aureus, S. epidermidis, S. warneri, S. hominis, and E. faecalis. We observed higher resistance rates in post–COVID-19 samples, as well as resistance to linezolid and vancomycin in S. aureus, S. epidermidis, and S. hominis. Additionally, our isolates showed a high resistance rate to antiseptics. Conclusions: It seems that after the beginning of the COVID-19 pandemic, due to the change in the protective procedures in hospitals, the prevalence and variety of bacteria have decreased, but instead, they have been replaced by more pathogenic bacteria with higher antibiotic resistance.
{"title":"Increasing Antimicrobial Resistance of Gram-Positive Cocci in the Nostrils of Health Care Workers in the Post–COVID-19 Era Compared to Pre–COVID-19 Era in North Khorasan, Iran","authors":"R. Besharati, Hatef Ajoudanifar, H. Ghasemzadeh-moghaddam, A. Azimian","doi":"10.5812/jjm-135551","DOIUrl":"https://doi.org/10.5812/jjm-135551","url":null,"abstract":"Background: In the COVID-19 era, co-infections can lead to an increase in morbidity and mortality. Normal flora bacteria can transfer to the pulmonary tract and create bacterial co-infections. The nasal cavity is one of the main areas housing normal flora in the human body. Objectives: In this study, we evaluated the prevalence and antibiotic resistance of gram-positive cocci in the pre– and post–COVID-19 eras among health care workers. Methods: We assessed 376 nasal swabs from the pre–COVID-19 era and 376 from the post–COVID-19 era. Conventional and molecular methods were used to identify bacterial types and evaluate antimicrobial resistance. Results: The most common gram-positive cocci in the pre–COVID-19 samples were Staphylococcus aureus, S. epidermidis, S. capitis, S. hominis, S. haemolyticus, Streptococcus pneumoniae, and Enterococcus faecalis. In the post–COVID-19 samples, the most common gram-positive cocci were S. aureus, S. epidermidis, S. warneri, S. hominis, and E. faecalis. We observed higher resistance rates in post–COVID-19 samples, as well as resistance to linezolid and vancomycin in S. aureus, S. epidermidis, and S. hominis. Additionally, our isolates showed a high resistance rate to antiseptics. Conclusions: It seems that after the beginning of the COVID-19 pandemic, due to the change in the protective procedures in hospitals, the prevalence and variety of bacteria have decreased, but instead, they have been replaced by more pathogenic bacteria with higher antibiotic resistance.","PeriodicalId":17803,"journal":{"name":"Jundishapur Journal of Microbiology","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42209310","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Background: Klebsiella pneumoniae is an important pathogen among nosocomial infections, which can cause urinary and respiratory system infections, surgical site infections, and sepsis. Recently, carbapenem-resistant K. pneumoniae showed an upward trend with the wide use of clinical carbapenem antibiotics. However, there are few studies on the relationship between drug resistance, virulence, and phylogeny of K. pneumoniae in patients with different infections. Objectives: We investigated the drug resistance, virulence, and phylogeny of K. pneumoniae in patients with different infections. Methods: Seventy infected patients were selected as subjects. The extended-spectrum β-lactamases (ESBLs) color screening plane and blood plate medium were used for culture. Identification and drug resistance analysis was carried out by VITEK-2 compact automatic bacterial analyzer. Multilocus sequence typing (MLST) and capsule genotyping analysis were also performed. The Xpert CarbaR cartridge detected the carbapenem resistance genes. Comprehensive Antibiotic Research Database (CARD) and Virulence Factor Database (VFDB) predicted the drug-resistant genes and virulence factor genes, respectively. The phylogenetic tree was constructed, and the correlation was analyzed. Results: A total of 43 K. pneumoniae strains were cultured. We found that all K. pneumoniae strains exhibited different multiple drug resistance. MLST analysis indicated that ST11 was the main ST (60.61%). Analysis of the carbapenem-resistance genes showed that all isolates harbored the blaKPC-2 gene and some others blaOXA. The prediction result of capsular blood genotyping and virulence factor genes indicated that K47, K64, and K25 were the main types of capsular blood, and the top three detection rates of virulence genes were fimH (97.67%), mrkD (94.19%), and entB (84.88%). All isolates were clustered into one branch based on the virulence factor genes in the phylogenetic tree, and the strains of the same ST type or capsular blood type showed a closer relationship. Correlation analysis manifested that the drug resistance of K. pneumoniae in infected patients was positively correlated with virulence and phylogeny (r = 0.682, P = 0.000). Conclusions: There were complicated differences in the multidrug resistance to K. pneumoniae, resulting in high independent gene-positive rates of strains and a strong correlation with phylogeny, which can provide a reference for the selection of clinical antimicrobial drugs.
{"title":"Analysis of Drug Resistance, Virulence, and Phylogeny of Klebsiella pneumoniae in Patients with Different Infections","authors":"Jianhua Liu, Rui Li, Shukun Qian, J. Xi","doi":"10.5812/jjm-133082","DOIUrl":"https://doi.org/10.5812/jjm-133082","url":null,"abstract":"Background: Klebsiella pneumoniae is an important pathogen among nosocomial infections, which can cause urinary and respiratory system infections, surgical site infections, and sepsis. Recently, carbapenem-resistant K. pneumoniae showed an upward trend with the wide use of clinical carbapenem antibiotics. However, there are few studies on the relationship between drug resistance, virulence, and phylogeny of K. pneumoniae in patients with different infections. Objectives: We investigated the drug resistance, virulence, and phylogeny of K. pneumoniae in patients with different infections. Methods: Seventy infected patients were selected as subjects. The extended-spectrum β-lactamases (ESBLs) color screening plane and blood plate medium were used for culture. Identification and drug resistance analysis was carried out by VITEK-2 compact automatic bacterial analyzer. Multilocus sequence typing (MLST) and capsule genotyping analysis were also performed. The Xpert CarbaR cartridge detected the carbapenem resistance genes. Comprehensive Antibiotic Research Database (CARD) and Virulence Factor Database (VFDB) predicted the drug-resistant genes and virulence factor genes, respectively. The phylogenetic tree was constructed, and the correlation was analyzed. Results: A total of 43 K. pneumoniae strains were cultured. We found that all K. pneumoniae strains exhibited different multiple drug resistance. MLST analysis indicated that ST11 was the main ST (60.61%). Analysis of the carbapenem-resistance genes showed that all isolates harbored the blaKPC-2 gene and some others blaOXA. The prediction result of capsular blood genotyping and virulence factor genes indicated that K47, K64, and K25 were the main types of capsular blood, and the top three detection rates of virulence genes were fimH (97.67%), mrkD (94.19%), and entB (84.88%). All isolates were clustered into one branch based on the virulence factor genes in the phylogenetic tree, and the strains of the same ST type or capsular blood type showed a closer relationship. Correlation analysis manifested that the drug resistance of K. pneumoniae in infected patients was positively correlated with virulence and phylogeny (r = 0.682, P = 0.000). Conclusions: There were complicated differences in the multidrug resistance to K. pneumoniae, resulting in high independent gene-positive rates of strains and a strong correlation with phylogeny, which can provide a reference for the selection of clinical antimicrobial drugs.","PeriodicalId":17803,"journal":{"name":"Jundishapur Journal of Microbiology","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43725061","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Shamsizadeh, N. Neisi, Seyede Shabnam Seyedsalehi, M. Fathi, Mohsen Alisamir, Seyed Mohammadreza Mirkarimi
Background: Viral infections are the most common cause of fever and neutropenia in children without underlying disease, and data are still limited in this regard. Objective: This study aimed to identify the most common viral causes of fever and neutropenia in pediatrics. Methods: This descriptive-analytical study was conducted on pediatric patients younger than 18 years old referred to the pediatric emergency ward with fever as the chief complaint and no underlying diseases; patients with neutropenia and no evidence of bacterial infections in terms of different cultures were included in the study. After obtaining parental consent, nasopharyngeal swab specimens were taken from patients during the coronavirus disease 2019 (COVID-19) pandemic, and blood samples were analyzed to detect viruses in each patient. Results: Fifty patients (54.3%) had mild neutropenia (absolute neutrophil count (ANC): 1000 - 1500/μL), 40 patients (43.5%) had moderate neutropenia (ANC: 1000 - 500/μL), and 2 cases (2.2%) had severe neutropenia (ANC < 500/μL). Among all the cases, 19 cases were positive in terms of virus examination, including adenovirus (6.5%), enterovirus (5.4%), cytomegalovirus (CMV) (3.3%), Epstein-Barr virus (EBV) (3.3%), and Herpes virus 6 (2.2%). A significant correlation was found between enterovirus and neutropenia (P = 0.005). Conclusions: The most common viruses found in neutropenic children hospitalized due to fever without any underlying disease were adenovirus and enterovirus, respectively. Considering the good general condition and relatively quick recovery, consideration of viral causes is recommended in this category of patients, and it is better to avoid prescribing broad-spectrum antibiotics, and careful follow-up should be carried out.
{"title":"Evaluation of the Most Common Viral Causes of Fever and Neutropenia in Children Hospitalized in Abuzar Children’s Medical Center in Ahvaz, Iran","authors":"A. Shamsizadeh, N. Neisi, Seyede Shabnam Seyedsalehi, M. Fathi, Mohsen Alisamir, Seyed Mohammadreza Mirkarimi","doi":"10.5812/jjm-135198","DOIUrl":"https://doi.org/10.5812/jjm-135198","url":null,"abstract":"Background: Viral infections are the most common cause of fever and neutropenia in children without underlying disease, and data are still limited in this regard. Objective: This study aimed to identify the most common viral causes of fever and neutropenia in pediatrics. Methods: This descriptive-analytical study was conducted on pediatric patients younger than 18 years old referred to the pediatric emergency ward with fever as the chief complaint and no underlying diseases; patients with neutropenia and no evidence of bacterial infections in terms of different cultures were included in the study. After obtaining parental consent, nasopharyngeal swab specimens were taken from patients during the coronavirus disease 2019 (COVID-19) pandemic, and blood samples were analyzed to detect viruses in each patient. Results: Fifty patients (54.3%) had mild neutropenia (absolute neutrophil count (ANC): 1000 - 1500/μL), 40 patients (43.5%) had moderate neutropenia (ANC: 1000 - 500/μL), and 2 cases (2.2%) had severe neutropenia (ANC < 500/μL). Among all the cases, 19 cases were positive in terms of virus examination, including adenovirus (6.5%), enterovirus (5.4%), cytomegalovirus (CMV) (3.3%), Epstein-Barr virus (EBV) (3.3%), and Herpes virus 6 (2.2%). A significant correlation was found between enterovirus and neutropenia (P = 0.005). Conclusions: The most common viruses found in neutropenic children hospitalized due to fever without any underlying disease were adenovirus and enterovirus, respectively. Considering the good general condition and relatively quick recovery, consideration of viral causes is recommended in this category of patients, and it is better to avoid prescribing broad-spectrum antibiotics, and careful follow-up should be carried out.","PeriodicalId":17803,"journal":{"name":"Jundishapur Journal of Microbiology","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43577173","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Maryam Khosravy, F. Hosseini, M. Razavi, Ramazan Ali Khavari
Background: Acinetobacter baumannii is an important cause of nosocomial pneumonia in patients requiring long-term mechanical ventilation. Besides, extensively drug-resistant (XDR) strains cause infection in intensive care unit (ICU) patients. Chronic infections of A. baumannii and antimicrobial resistance are associated with biofilm formation. Several virulence genes, such as blaPER-1, pgaA, and bap, are involved in biofilm formation. Objectives: The current study examines the expression levels of biofilm formation-related genes in pneumonia patients. Methods: The sputum samples were collected from patients hospitalized in the ICU, and A. baumannii ATCC 19606, the reference strain, was isolated and cultured on blood agar, eosin methylene blue agar, and chocolate agar medium. The media were then incubated at 37°C for 18 - 24 hours. Next, Gram-Thirty XDR A. baumannii isolates were collected from the sputum samples of ICU patients at Besat Hospital in Tehran, Iran. Bacterial isolates were characterized for antibiotic resistance patterns and biofilm-forming ability. Subsequently, RNA was extracted from the biofilm-forming isolates. A real-time polymerase chain reaction (PCR) assay was performed to evaluate the expression levels of the blaPER-1, pgaA, and bap genes. Transcripts were normalized to 16S rRNA as an internal control, and gene expression fold changes were calculated. Statistical analysis was performed using an unpaired two-tailed t-test (P < 0.05) with SPSS (V. 16). Results: The disk diffusion susceptibility test revealed that all 30 (100%) isolates were resistant to piperacillin-tazobactam, cefepime, ceftriaxone, ceftazidime, gentamicin, imipenem, meropenem, levofloxacin, and ciprofloxacin. All 30 isolates from ICU-admitted patients (100%) were classified as XDR, and 27 (90%) isolates demonstrated the ability to form biofilms. The obtained results indicated a significant difference in gene expression levels. The fold change in expression for blaPER-1, bap, and pgaA was 7.473, 11.964, and 5.277, respectively. Conclusions: In our study, XDR A. baumannii primarily caused ventilator-associated pneumonia, and an observed increase in the expression of biofilm-related genes was noted in these strains. Healthcare centers should implement appropriate infection control programs to manage nosocomial infections, particularly in the ICU.
{"title":"Expression of Biofilm-Related Genes in Extensively Drug-Resistant Acinetobacter baumannii","authors":"Maryam Khosravy, F. Hosseini, M. Razavi, Ramazan Ali Khavari","doi":"10.5812/jjm-133999","DOIUrl":"https://doi.org/10.5812/jjm-133999","url":null,"abstract":"Background: Acinetobacter baumannii is an important cause of nosocomial pneumonia in patients requiring long-term mechanical ventilation. Besides, extensively drug-resistant (XDR) strains cause infection in intensive care unit (ICU) patients. Chronic infections of A. baumannii and antimicrobial resistance are associated with biofilm formation. Several virulence genes, such as blaPER-1, pgaA, and bap, are involved in biofilm formation. Objectives: The current study examines the expression levels of biofilm formation-related genes in pneumonia patients. Methods: The sputum samples were collected from patients hospitalized in the ICU, and A. baumannii ATCC 19606, the reference strain, was isolated and cultured on blood agar, eosin methylene blue agar, and chocolate agar medium. The media were then incubated at 37°C for 18 - 24 hours. Next, Gram-Thirty XDR A. baumannii isolates were collected from the sputum samples of ICU patients at Besat Hospital in Tehran, Iran. Bacterial isolates were characterized for antibiotic resistance patterns and biofilm-forming ability. Subsequently, RNA was extracted from the biofilm-forming isolates. A real-time polymerase chain reaction (PCR) assay was performed to evaluate the expression levels of the blaPER-1, pgaA, and bap genes. Transcripts were normalized to 16S rRNA as an internal control, and gene expression fold changes were calculated. Statistical analysis was performed using an unpaired two-tailed t-test (P < 0.05) with SPSS (V. 16). Results: The disk diffusion susceptibility test revealed that all 30 (100%) isolates were resistant to piperacillin-tazobactam, cefepime, ceftriaxone, ceftazidime, gentamicin, imipenem, meropenem, levofloxacin, and ciprofloxacin. All 30 isolates from ICU-admitted patients (100%) were classified as XDR, and 27 (90%) isolates demonstrated the ability to form biofilms. The obtained results indicated a significant difference in gene expression levels. The fold change in expression for blaPER-1, bap, and pgaA was 7.473, 11.964, and 5.277, respectively. Conclusions: In our study, XDR A. baumannii primarily caused ventilator-associated pneumonia, and an observed increase in the expression of biofilm-related genes was noted in these strains. Healthcare centers should implement appropriate infection control programs to manage nosocomial infections, particularly in the ICU.","PeriodicalId":17803,"journal":{"name":"Jundishapur Journal of Microbiology","volume":"257 2","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41278852","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Background: More and more variants of concern (VOCs) of SARS-CoV-2 continued to emerge in different regions worldwide. Objectives: Studies on COVID-19 outbreaks caused by different VOCs are critical for understanding their infections in humans in different regions. Methods: In this descriptive study, the individual information of 64 confirmed COVID-19 cases reported between March 3 and April 26, 2022, was collected, and the epidemiological features were analyzed. Results: We found COVID-19 epidemic caused by Omicron subvariant BA.2 in 2022 had unique characteristics compared to the earliest COVID-19 outbreaks in 2020 in Wuhu city. First, the geographic distribution of COVID-19 cases was highly concentrated, and most infections (58/64, 90.62%) were identified in one district in this study. Second, the mean age of COVID-19 cases in this study was 39.57 ± 16.39 years old, which was younger than the COVID-19 cases identified in Wuhan and Wuhu cities in 2020. Third, the spanned period of the COVID-19 outbreak in this study was shorter than the COVID-19 outbreak in 2020 in Wuhu city (13 days vs. 34 days). Conclusions: This study illustrates the epidemic of COVID-19 in Wuhu city from March to April 2022, and our result provides valuable information about COVID-19 outbreak caused by omicron subvariant BA.2. It also provides insights into developing effective strategies, such as high coverage of COVID-19 vaccination, lockdown policies, Ankang code, and population-bases COVID-19 screening, for successfully controlling the potential outbreaks caused by Omicron or future novel variants of SARS-CoV-2 in the medium-sized city like Wuhu.
{"title":"Epidemiological Analysis and Effective Control of COVID-19 Outbreaks Caused by the Omicron Subvariant BA.2 in a Medium-sized City in China, 2022","authors":"Zhu Yang, Jinhong Zhao, Shuzhi Zhong, Yikun Wu, Bingjie Ye, Yiming Wang, Minmin Xiao","doi":"10.5812/jjm-136649","DOIUrl":"https://doi.org/10.5812/jjm-136649","url":null,"abstract":"Background: More and more variants of concern (VOCs) of SARS-CoV-2 continued to emerge in different regions worldwide. Objectives: Studies on COVID-19 outbreaks caused by different VOCs are critical for understanding their infections in humans in different regions. Methods: In this descriptive study, the individual information of 64 confirmed COVID-19 cases reported between March 3 and April 26, 2022, was collected, and the epidemiological features were analyzed. Results: We found COVID-19 epidemic caused by Omicron subvariant BA.2 in 2022 had unique characteristics compared to the earliest COVID-19 outbreaks in 2020 in Wuhu city. First, the geographic distribution of COVID-19 cases was highly concentrated, and most infections (58/64, 90.62%) were identified in one district in this study. Second, the mean age of COVID-19 cases in this study was 39.57 ± 16.39 years old, which was younger than the COVID-19 cases identified in Wuhan and Wuhu cities in 2020. Third, the spanned period of the COVID-19 outbreak in this study was shorter than the COVID-19 outbreak in 2020 in Wuhu city (13 days vs. 34 days). Conclusions: This study illustrates the epidemic of COVID-19 in Wuhu city from March to April 2022, and our result provides valuable information about COVID-19 outbreak caused by omicron subvariant BA.2. It also provides insights into developing effective strategies, such as high coverage of COVID-19 vaccination, lockdown policies, Ankang code, and population-bases COVID-19 screening, for successfully controlling the potential outbreaks caused by Omicron or future novel variants of SARS-CoV-2 in the medium-sized city like Wuhu.","PeriodicalId":17803,"journal":{"name":"Jundishapur Journal of Microbiology","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44229519","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Samaneh Ghafari, R. Mirnejad, Fatemeh Sameni, Mohamad Hoseyn Dehghan-Tarazjani, Mansoor Khaledi, M. Niakan
Background: Acinetobacter baumannii is one of the most important known causes of hospital infections worldwide that is resistant to many common antibiotics. Efflux pumps are among the main reasons behind resistance in this bacterium. Objectives: This study was conducted to investigate the presence of efflux pump genes (adeI, adeJ) in clinical antibiotic-resistant isolates of A. baumannii in Tehran hospitals. Methods: One hundred fifty clinical samples of wounds, urine, sputum, and blood were collected periodically (6 months) from Tehran hospitals. A. baumannii was identified using common biochemical methods. After conducting biochemical tests, the final confirmation of the samples was performed by examining the blaOXA-51-like gene by molecular polymerase chain reaction (PCR) method. The disk diffusion antimicrobial susceptibility testing was performed using Mueller Hinton agar growth medium according to Clinical and Laboratory Standards Institute (CLSI) guidelines on nine antibiotics. Then the samples were investigated for the presence of adeI and adeJ genes. Results: Examining the antibiotic resistance of the isolates showed that the resistance level varied from 48.1% to 98.2%, depending on the antibiotic type. In this study, isolates showed the highest and lowest resistance to tetracycline and gentamicin, respectively. Also, positive isolates for the presence of adeI and adeJ genes showed the highest resistance to tetracycline, amikamycin, ceftazidime, and ceftriaxone. Isolates that were negative for the presence of these two genes showed the highest sensitivity to imipenem, gentamicin, and ciprofloxacin. Conclusions: In this study, the correlation of antibiotic resistance test and PCR results showed that the presence of adeI and adeJ genes in the samples significantly increased the resistance to all investigated antibiotics. Therefore, evaluating efflux pumps proves to be useful in identifying antibiotic-resistant strains and appropriate drug treatment. Of course, the role of other factors in creating resistance should not be neglected.
{"title":"Investigating the Presence of Efflux Pump Genes adeI and adeJ in Clinical Antibiotic-Resistant Isolates of Acinetobacter baumannii","authors":"Samaneh Ghafari, R. Mirnejad, Fatemeh Sameni, Mohamad Hoseyn Dehghan-Tarazjani, Mansoor Khaledi, M. Niakan","doi":"10.5812/jjm-135795","DOIUrl":"https://doi.org/10.5812/jjm-135795","url":null,"abstract":"Background: Acinetobacter baumannii is one of the most important known causes of hospital infections worldwide that is resistant to many common antibiotics. Efflux pumps are among the main reasons behind resistance in this bacterium. Objectives: This study was conducted to investigate the presence of efflux pump genes (adeI, adeJ) in clinical antibiotic-resistant isolates of A. baumannii in Tehran hospitals. Methods: One hundred fifty clinical samples of wounds, urine, sputum, and blood were collected periodically (6 months) from Tehran hospitals. A. baumannii was identified using common biochemical methods. After conducting biochemical tests, the final confirmation of the samples was performed by examining the blaOXA-51-like gene by molecular polymerase chain reaction (PCR) method. The disk diffusion antimicrobial susceptibility testing was performed using Mueller Hinton agar growth medium according to Clinical and Laboratory Standards Institute (CLSI) guidelines on nine antibiotics. Then the samples were investigated for the presence of adeI and adeJ genes. Results: Examining the antibiotic resistance of the isolates showed that the resistance level varied from 48.1% to 98.2%, depending on the antibiotic type. In this study, isolates showed the highest and lowest resistance to tetracycline and gentamicin, respectively. Also, positive isolates for the presence of adeI and adeJ genes showed the highest resistance to tetracycline, amikamycin, ceftazidime, and ceftriaxone. Isolates that were negative for the presence of these two genes showed the highest sensitivity to imipenem, gentamicin, and ciprofloxacin. Conclusions: In this study, the correlation of antibiotic resistance test and PCR results showed that the presence of adeI and adeJ genes in the samples significantly increased the resistance to all investigated antibiotics. Therefore, evaluating efflux pumps proves to be useful in identifying antibiotic-resistant strains and appropriate drug treatment. Of course, the role of other factors in creating resistance should not be neglected.","PeriodicalId":17803,"journal":{"name":"Jundishapur Journal of Microbiology","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46986248","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fereshteh Hasanpour, Nima Ataei, A. Sahebkar, F. Khademi
Background: Currently, the emergence of extended-spectrum β-lactamase (ESBL)-producing bacteria is becoming a major threat to patients in the hospital and community. Such enzymes have been recently detected in Pseudomonas aeruginosa, but there is no epidemiological data on the prevalence of ESBL-producing clinical isolates in the hospitals of Ardabil City (Iran). Objectives: This study aimed to determine the phenotypic and genotypic prevalence of class A ESBL-producing P. aeruginosa strains in Ardabil City. Methods: A total of 120 clinical isolates of P. aeruginosa collected from Ardabil hospitals were used in this study. Phenotypic detection of class A ESBL-producing P. aeruginosa isolates was performed using a double-disk synergy test. In addition, the detection of class A ESBL-encoding genes, including Pseudomonas extended resistant (PER), Vietnamese extended-spectrum β-lactamase (VEB), temoniera (TEM), sulfhydryl variable (SHV), cefotaximase (CTX-M), guyana extended-spectrum β-lactamase (GES), and Pseudomonas-specific enzyme (PSE), was performed using the polymerase chain reaction (PCR). Results: The prevalence of class A ESBL-producing P. aeruginosa strains was 8.3% (10 out of 120) based on the double-disk synergy test. However, 40% (48 out of 120) of these isolates were found to carry genes encoding class A ESBLs based on PCR. Among 48 class A ESBL-positive strains, the prevalence of PSE, TEM, VEB, CTX-M, and PER genes were 64.6% (31/48), 25% (12/48), 4.2% (2/48), 4.2% (2/48), and 2% (1/48), respectively. However, the frequency of other class A ESBL genes (SHV and GES genes) was 0%. Conclusions: Our results confirmed the presence of class A ESBL-producing P. aeruginosa strains in the hospital environment of Ardabil. On the other hand, the use of molecular tests can be a more precise and reliable method than phenotypic ones to identify these resistant strains and prevent the emergence of antibiotic resistance and ensuing treatment failure.
{"title":"Distribution of Class A Extended-Spectrum β-Lactamases Among Pseudomonas aeruginosa Clinical Strains Isolated from Ardabil Hospitals","authors":"Fereshteh Hasanpour, Nima Ataei, A. Sahebkar, F. Khademi","doi":"10.5812/jjm-135726","DOIUrl":"https://doi.org/10.5812/jjm-135726","url":null,"abstract":"Background: Currently, the emergence of extended-spectrum β-lactamase (ESBL)-producing bacteria is becoming a major threat to patients in the hospital and community. Such enzymes have been recently detected in Pseudomonas aeruginosa, but there is no epidemiological data on the prevalence of ESBL-producing clinical isolates in the hospitals of Ardabil City (Iran). Objectives: This study aimed to determine the phenotypic and genotypic prevalence of class A ESBL-producing P. aeruginosa strains in Ardabil City. Methods: A total of 120 clinical isolates of P. aeruginosa collected from Ardabil hospitals were used in this study. Phenotypic detection of class A ESBL-producing P. aeruginosa isolates was performed using a double-disk synergy test. In addition, the detection of class A ESBL-encoding genes, including Pseudomonas extended resistant (PER), Vietnamese extended-spectrum β-lactamase (VEB), temoniera (TEM), sulfhydryl variable (SHV), cefotaximase (CTX-M), guyana extended-spectrum β-lactamase (GES), and Pseudomonas-specific enzyme (PSE), was performed using the polymerase chain reaction (PCR). Results: The prevalence of class A ESBL-producing P. aeruginosa strains was 8.3% (10 out of 120) based on the double-disk synergy test. However, 40% (48 out of 120) of these isolates were found to carry genes encoding class A ESBLs based on PCR. Among 48 class A ESBL-positive strains, the prevalence of PSE, TEM, VEB, CTX-M, and PER genes were 64.6% (31/48), 25% (12/48), 4.2% (2/48), 4.2% (2/48), and 2% (1/48), respectively. However, the frequency of other class A ESBL genes (SHV and GES genes) was 0%. Conclusions: Our results confirmed the presence of class A ESBL-producing P. aeruginosa strains in the hospital environment of Ardabil. On the other hand, the use of molecular tests can be a more precise and reliable method than phenotypic ones to identify these resistant strains and prevent the emergence of antibiotic resistance and ensuing treatment failure.","PeriodicalId":17803,"journal":{"name":"Jundishapur Journal of Microbiology","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43703876","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Background: Carbapenem-resistant Pseudomonas aeruginosa is an endemic problem in several countries, notably Turkey. Objectives: This study aimed to investigate the underlying mechanisms contributing to the carbapenem resistance phenotype and enhance the in-vitro activity of ceftolozane-tazobactam (C/T) and ceftazidime-avibactam (C/A) against carbapenem-resistant P. aeruginosa strains. Methods: A total of 114 carbapenem-resistant P. aeruginosa strains were isolated from different types of clinical specimens. The tested antibiotics were evaluated using the antibiotic disk diffusion method. Additionally, C/T and C/A were tested using the gradient test method. The efficacy of phenylalanine-arginine-β-naphthylamide (PAβN) as efflux pump inhibitors was assessed to determine their ability to reduce meropenem minimum inhibitory concentrations. Polymerase chain reaction (PCR) assays were conducted to identify blaIMP, blaVIM, and blaNDM-1. Results: Among 114 strains of carbapenem-resistant P. aeruginosa, overall resistance rates for C/T and C/A were 10.7% and 8.8%, respectively. Efflux pump inhibitor-based antibiotic susceptibility testing indicated that 35.08% of strains showed resistance modulated by PAβN. Among the strains, 27 (24.5%) were found to produce metallo-beta-lactamase (MBL), with blaVIM (17 strains, 14.91%) being the most common, followed by blaIMP (12 strains, 10.53%). Conclusions: Emerging carbapenem resistance in P. aeruginosa strains is a serious therapeutic challenge for clinicians. Carbapenem resistance can be influenced by various factors, some of which were not assessed in our study. Nonetheless, our results revealed that the main mechanism associated with carbapenem-resistant P. aeruginosa strains is a PAβN-sensitive efflux pump. Among acquired MBLs, VIM-type enzymes were found to be the most prevalent.
{"title":"Evaluation of In Vitro Activity of Ceftolozane/Tazobactam and Ceftazidime/Avibactam Against Carbapenem-Resistant Pseudomonas aeruginosa Strains and Mechanisms of Carbapenem Resistance: Data from Tertiary Care Hospital","authors":"G. Hazırolan, Ceren Özkul","doi":"10.5812/jjm-134090","DOIUrl":"https://doi.org/10.5812/jjm-134090","url":null,"abstract":"Background: Carbapenem-resistant Pseudomonas aeruginosa is an endemic problem in several countries, notably Turkey. Objectives: This study aimed to investigate the underlying mechanisms contributing to the carbapenem resistance phenotype and enhance the in-vitro activity of ceftolozane-tazobactam (C/T) and ceftazidime-avibactam (C/A) against carbapenem-resistant P. aeruginosa strains. Methods: A total of 114 carbapenem-resistant P. aeruginosa strains were isolated from different types of clinical specimens. The tested antibiotics were evaluated using the antibiotic disk diffusion method. Additionally, C/T and C/A were tested using the gradient test method. The efficacy of phenylalanine-arginine-β-naphthylamide (PAβN) as efflux pump inhibitors was assessed to determine their ability to reduce meropenem minimum inhibitory concentrations. Polymerase chain reaction (PCR) assays were conducted to identify blaIMP, blaVIM, and blaNDM-1. Results: Among 114 strains of carbapenem-resistant P. aeruginosa, overall resistance rates for C/T and C/A were 10.7% and 8.8%, respectively. Efflux pump inhibitor-based antibiotic susceptibility testing indicated that 35.08% of strains showed resistance modulated by PAβN. Among the strains, 27 (24.5%) were found to produce metallo-beta-lactamase (MBL), with blaVIM (17 strains, 14.91%) being the most common, followed by blaIMP (12 strains, 10.53%). Conclusions: Emerging carbapenem resistance in P. aeruginosa strains is a serious therapeutic challenge for clinicians. Carbapenem resistance can be influenced by various factors, some of which were not assessed in our study. Nonetheless, our results revealed that the main mechanism associated with carbapenem-resistant P. aeruginosa strains is a PAβN-sensitive efflux pump. Among acquired MBLs, VIM-type enzymes were found to be the most prevalent.","PeriodicalId":17803,"journal":{"name":"Jundishapur Journal of Microbiology","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47592191","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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