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Acta Microbiologica Et Immunologica... Jul 2024The present study aimed to explore the genomic characteristics of eight New Delhi metallo-β-lactamase-1 (NDM-1)-producing carbapenem-resistant Pseudomonas aeruginosa...
The present study aimed to explore the genomic characteristics of eight New Delhi metallo-β-lactamase-1 (NDM-1)-producing carbapenem-resistant Pseudomonas aeruginosa (CRPA) isolates from a Bulgarian tertiary hospital (2021-2023) in comparison to blaNDM-1-positive strains originating from the Balkans. Antimicrobial susceptibility testing, phenotypic assays for carbapenemase activity, PCR screening, whole-genome sequencing (WGS), and phylogenomic analysis were performed. Seven of the CRPA isolates investigated (Minimum inhibitory concentration values of imipenem and meropenem >32 mg L-1) were also resistant to piperacillin-tazobactam, ceftazidime, ceftazidime-avibactam, cefepime, ceftolozane-tazobactam, amikacin, tobramycin, ciprofloxacin, and levofloxacin, but were susceptible to colistin (0.5-2 mg L-1) and cefiderocol (0.25-1 mg L-1). The P. aeruginosa Pae57 isolate (designated Pae57) remained susceptible to aminoglycosides as well. WGS uncovered the co-existence of blaNDM-1 and blaGES-1. The isolates belonged to the ST654 high-risk clone, except for Pae57 (ST611). Alignment against reference sequences revealed the presence of a Tn21 transposon harboring bleMBL-blaNDM-1-ISAba125. It was similar to that found in the P. aeruginosa ST654 NDM1_1 strain (GCA_020404785.1) from Serbia. Phylogenomic analysis of our isolates indicated that seven of them (ST654) differed from each other in no more than 44 single-nucleotide polymorphisms (SNPs). Pae57 (ST611) was strikingly different (>21,700 SNPs) compared to all Balkan strains. In conclusion, to our knowledge this is the first report of blaNDM-1-positive P. aeruginosa ST611 isolation, which indicates the transmission dynamics of this determinant between high-risk and potentially high-risk P. aeruginosa clones. Obtained results unveil the dissemination of clonally related NDM-1-producing P. aeruginosa strains in the monitored hospital for approximately a 2-year period.
Topics: Pseudomonas aeruginosa; beta-Lactamases; Humans; Tertiary Care Centers; Bulgaria; Microbial Sensitivity Tests; Anti-Bacterial Agents; Pseudomonas Infections; Phylogeny; Whole Genome Sequencing; Genome, Bacterial; Bacterial Proteins; Drug Resistance, Multiple, Bacterial
PubMed: 38857113
DOI: 10.1556/030.2024.02309 -
Iranian Journal of Microbiology Apr 2024is a significant causative agent of bloodstream infections (BSIs). Aminoglycoside antibiotics play a crucial role in treating severe infections such as sepsis and...
BACKGROUND AND OBJECTIVES
is a significant causative agent of bloodstream infections (BSIs). Aminoglycoside antibiotics play a crucial role in treating severe infections such as sepsis and pneumonia. However, resistance to these antibiotics often occurs due to the production of aminoglycoside-modifying enzymes (AMEs). This study was conducted to assess antimicrobial susceptibility patterns against various aminoglycosides and to determine the prevalence of common AME genes in strains isolated from BSIs.
MATERIALS AND METHODS
Sixty-five isolates were obtained from blood samples in a referral hospital in Tehran, Iran. The susceptibility patterns of aminoglycosides were determined using disk diffusion method and AMEs genes were investigated using PCR assay.
RESULTS
Resistance to aminoglycosides was observed in 64.6% (42/65) of the isolates. The most frequent resistance rate was found for kanamycin (44.6%) and gentamicin (38.5%), followed by tobramycin (29.2%) and amikacin (4.6%). The most frequent AME gene was , which detected in 49.2% isolates, followed by (40%), (32.3%), and (30.8%), respectively.
CONCLUSION
Athough the findings of this survey are based on specimens collected from a single hospital, our study shows that the high prevalence of aminoglycoside resistance is primarily attributed to the presence of the and genes. The low rate of resistance to amikacin makes this antibiotic a good candidate for treatment of BSIs due to
PubMed: 38854982
DOI: 10.18502/ijm.v16i2.15351 -
Iranian Journal of Microbiology Apr 2024Multi-drug-resistant pathogens pose a significant threat as they can rapidly spread, leading to severe healthcare-associated invasive infections. In developing...
BACKGROUND AND OBJECTIVES
Multi-drug-resistant pathogens pose a significant threat as they can rapidly spread, leading to severe healthcare-associated invasive infections. In developing countries, diarrheagenic (DEC) is a major bacterial pathogen responsible for causing diarrhea. However, the outbreak of resistant strains has made the treatment of DEC infections much more challenging. This study aimed to investigate the relationship between antibiotic resistance genes and other virulence categories in strains that cause diarrhea, particularly DEC.
MATERIALS AND METHODS
The phylogenetic grouping was defined using PCR and multi-locus sequence type (MLST) methods.
RESULTS
Among the isolates analyzed, 14 were identified as resistant and were classified into eight distinct sequence types: ST3, ST53, ST77, ST483, ST512, ST636, ST833, and ST774, indicating genetic diversity among the resistant strains. Certain sequence types, notably ST512 and ST636, were found to be associated with multiple antibiotic resistance in DEC. Regarding antibiotic susceptibility, strains showed the highest resistance to amoxicillin, suggesting that this antibiotic may not be effective in treating DEC infections. On the other hand, the isolates demonstrated susceptibility to amikacin and chloramphenicol, implying that these antibiotics could be more suitable treatment options for DEC infections.
CONCLUSION
The findings underscore the importance of promptly identifying antibiotic resistance patterns and their correlation with specific pathogenic virulence categories, as this knowledge can aid in selecting the most appropriate antibiotics for treating DEC infections. Considering the antibiotic resistance profiles and associated resistance genes is crucial in managing and containing diarrheal outbreaks and in selecting effective antibiotic therapies for DEC infections.
PubMed: 38854980
DOI: 10.18502/ijm.v16i2.15350 -
Journal of Global Antimicrobial... Jun 2024Hypervirulent carbapenem-resistant Klebsiella pneumoniae (hv-CRKp) poses a significant threat to public health. This study reports an infection related to hv-CRKp in a...
OBJECTIVES
Hypervirulent carbapenem-resistant Klebsiella pneumoniae (hv-CRKp) poses a significant threat to public health. This study reports an infection related to hv-CRKp in a premature infant and reveals its colistin resistance and evolutionary mechanisms within the host.
METHODS
Three KPC-producing CRKp strains were isolated from a patient with sepsis and CRKp osteoarthritis who had been receiving colistin antimicrobial therapy. The minimum inhibitory concentrations (MICs) of Ceftazidime,Ceftazidime-Avibactam(CAZ-AVI),Meropenem,Imipenem,Tigecycline,Amikacin,Minocycline,Sulfamethoxazole/Trimethoprim,Ciprofloxacin,Levofloxacin,Aztreonam,Cefepime,Cefoperazone/Sulbactam,Piperacillin/Tazobactam and colistin were determined using the microbroth dilution method.The whole-genome sequencing analysis was conducted to determine the STs, virulence genes, and antibiotic resistance genes of three CRKp strains.
RESULTS
Whole-genome sequencing revealed that all three CRKp strains belonged to the sequence type (ST) 11 clone and carried a plasmid encoding blaKPC-2. The three strains all possessed the iucABCDiutA virulence cluster, peg-344 gene, and rmpA/rmpA2 genes, defining them as hv-CRKp. Further experiments and whole-genome analysis revealed that a strain of Kp has developed resistance to colistin. The mechanism found to be responsible for the colistin resistance was a deletion mutation of approximately 9000 bp including mgrB gene.
CONCLUSION
This study characterizes the colistin resistance of ST11 clone hv-CRKp during colistin treatment and its rapid evolution within the host.
PubMed: 38849114
DOI: 10.1016/j.jgar.2024.05.021 -
Annals of Medicine and Surgery (2012) Jun 2024Kidney damage can result from various factors, leading to structural and functional changes in the kidney. Acute kidney injury (AKI) refers to a sudden decline in kidney... (Review)
Review
INTRODUCTION
Kidney damage can result from various factors, leading to structural and functional changes in the kidney. Acute kidney injury (AKI) refers to a sudden decline in kidney function, while chronic kidney disease involves a gradual deterioration lasting more than 3 months. Mechanisms of renal injury include impaired microcirculation, inflammation, and oxidative stress. Cysteinyl-leukotrienes (CysLTs) are inflammatory substances contributing to tissue damage. Montelukast, a leukotriene receptor antagonist, has shown potential renoprotective effects in experimental models of kidney injury.
METHODS
The authors conducted a scoping review using PubMed, Scopus, and Web of Science databases to identify relevant studies investigating the impact of montelukast on renal diseases. Articles published until 2022 were included and evaluated for quality. Data extraction and analysis were performed based on predetermined inclusion criteria.
RESULTS
The scoping review included 30 studies from 8 countries. Montelukast demonstrated therapeutic effects in various experimental models of nephrotoxicity and AKI induced by agents such as cisplatin, lipopolysaccharide, diclofenac, amikacin, , cyclosporine, methotrexate, cobalt-60 gamma radiation, doxorubicin, and cadmium. Studies involving human subjects with nephrotic syndrome, pyelonephritis, and other renal diseases also reported positive outcomes with montelukast treatment. Montelukast exhibited anti-inflammatory, anti-apoptotic, antioxidant, and neutrophil-inhibiting properties, leading to improved kidney function and histopathological changes.
CONCLUSIONS
Montelukast shows promise as a renoprotective medication, particularly in early-stage kidney injury. Its ability to mitigate inflammation, oxidative stress, and neutrophil infiltration contributes to its therapeutic effects. Further research is needed to explore the clinical applications and mechanisms underlying the renoprotective action of montelukast.
PubMed: 38846849
DOI: 10.1097/MS9.0000000000002085 -
European Journal of Case Reports in... 2024Blue rubber bleb nevus syndrome is a rare disorder of venous malformations, with around 200 cases reported. We present a case of infection in a patient with blue rubber...
INTRODUCTION
Blue rubber bleb nevus syndrome is a rare disorder of venous malformations, with around 200 cases reported. We present a case of infection in a patient with blue rubber bleb nevus syndrome.
CASE DESCRIPTION
A 40-year-old female with blue rubber bleb nevus syndrome, asthma, and bronchiectasis came to the pulmonology clinic with shortness of breath and a cough. She was recently admitted for a bronchiectasis exacerbation but continued to have a worsening productive cough and fevers. The most recent CT scan of the chest showed interval stable right upper lobe fibrocavitary disease, demonstrating gradual progression over two years. She had occasional positive cultures for and one year previously, assumed to be a colonizer and not treated. Most recent hospital cultures were negative for bacteria and an acid-fast bacilli smear. She was sent to the emergency department for bronchiectasis exacerbation and returned to the clinic six weeks later with two sputum cultures growing . It was decided to treat as this was likely the cause of her cavitary lung lesion and frequent infections. Azithromycin, rifampin, and sulfamethoxazole/trimethoprim were initiated. Intravenous amikacin was added later on. She finally had a right partial lung resection done after one year at an outside hospital. She was on and off antibiotics for for approximately three years with negative repeat cultures for non-tuberculous mycobacteria.
CONCLUSION
Due to the high mortality of infections (which can be as high as 69%), treatment of at least twelve months is recommended. To our knowledge, this is the first reported case of in a patient with blue rubber bleb nevus syndrome.
LEARNING POINTS
The decision to initiate treatment for non-tuberculous mycobacterium infections is often challenging with prolonged treatment.Lifetime monitoring is required in patients with blue rubber bleb nevus syndrome, which can have pulmonary complications. has the highest mortality among non-tuberculous mycobacterium infections and requires at least 12 months of treatment.
PubMed: 38846651
DOI: 10.12890/2024_004530 -
PLoS Pathogens Jun 2024Amikacin and piperacillin/tazobactam are frequent antibiotic choices to treat bloodstream infection, which is commonly fatal and most often caused by bacteria from the...
Amikacin and piperacillin/tazobactam are frequent antibiotic choices to treat bloodstream infection, which is commonly fatal and most often caused by bacteria from the family Enterobacterales. Here we show that two gene cassettes located side-by-side in and ancestral integron similar to In37 have been "harvested" by insertion sequence IS26 as a transposon that is widely disseminated among the Enterobacterales. This transposon encodes the enzymes AAC(6')-Ib-cr and OXA-1, reported, respectively, as amikacin and piperacillin/tazobactam resistance mechanisms. However, by studying bloodstream infection isolates from 769 patients from three hospitals serving a population of 1.2 million people in South West England, we show that increased enzyme production due to mutation in an IS26/In37-derived hybrid promoter or, more commonly, increased transposon copy number is required to simultaneously remove these two key therapeutic options; in many cases leaving only the last-resort antibiotic, meropenem. These findings may help improve the accuracy of predicting piperacillin/tazobactam treatment failure, allowing stratification of patients to receive meropenem or piperacillin/tazobactam, which may improve outcome and slow the emergence of meropenem resistance.
Topics: Humans; Anti-Bacterial Agents; DNA Transposable Elements; Drug Resistance, Multiple, Bacterial; Piperacillin; Amikacin; Microbial Sensitivity Tests; Enterobacteriaceae Infections; Enterobacteriaceae; Integrons; Bacteremia
PubMed: 38843111
DOI: 10.1371/journal.ppat.1012235 -
Veterinary Medicine and Science Jul 2024Ornithobacterium rhinotracheal (ORT) infects numerous birds, particularly chickens and turkeys. ORT is an emerging bacterial pathogen of global concern in the poultry...
BACKGROUND
Ornithobacterium rhinotracheal (ORT) infects numerous birds, particularly chickens and turkeys. ORT is an emerging bacterial pathogen of global concern in the poultry industry. As ORT is rapidly spreading throughout commercial poultry, it requires intensive studies of its epidemiology, diagnostic procedures, molecular typing, virulence genes and antimicrobial resistance.
OBJECTIVES
The present study was conducted in isolation and identification of ORT from slaughtered turkeys.
METHODS
Cleft palate swabs of 200 were collected from slaughtered turkeys and cultured on blood agar. ORT was characterized using biochemical tests and PCR targeting the ORT 16S rRNA gene. Virulence genes of isolates were determined targeting adenylate kinase (adk), copA and virulence-associated protein D (vapD) genes. Additionally, diversity of ORT isolates was performed by enterobacterial repetitive intergenic consensus (ERIC) and RAPD PCR. Disk diffusion was used to determine the antibiotic sensitivity of the isolates.
RESULTS
ORT was identified in 23 (11.5%) samples using both the biochemical tests and PCR. The result of detecting virulence genes showed that all the isolates (23: 100%) had the adk gene, whereas two (8.7%) isolates had the copA gene, and seven (30.43%) isolates had the vapD gene. Molecular typing of isolates revealed 21 different patterns by RAPD PCR assay using M13 primer and 20 distinct patterns by ERIC PCR test. Both ERIC and RAPD PCR were distinctive methods for investigating the genetic diversity of ORT isolates. The antibiotic resistance test showed that 18 (78.26%) isolates were resistant to gentamicin, amikacin, cefazolin, streptomycin and penicillin. All isolates (100%) were resistant to cloxacillin and fosfomycin.
CONCLUSIONS
This study showed the prevalence of ORT in turkey and high resistance of this bacterium to many common veterinary antibiotics. Moreover, both ERIC and RAPD PCR are distinctive methods for investigating the genetic diversity of ORT isolates. These data may help monitor antibiotic resistance and typing of ORT in epidemiological studies and serve as the foundation for designing region-specific vaccines for future use.
Topics: Animals; Turkeys; Poultry Diseases; Ornithobacterium; Flavobacteriaceae Infections; Drug Resistance, Bacterial; Anti-Bacterial Agents
PubMed: 38837675
DOI: 10.1002/vms3.1490 -
Cureus May 2024A 47-year-old male, a known case of alcoholic chronic liver disease with portal hypertension, presented with complaints of abdominal distension and shortness of breath....
Iatrogenically Acquired Mycobacterium abscessus Infection in an Indwelling Intercostal Drainage In Situ in a Patient With Alcoholic Liver Disease and Bilateral Hepatic Hydrothorax: A Report of a Rare Case.
A 47-year-old male, a known case of alcoholic chronic liver disease with portal hypertension, presented with complaints of abdominal distension and shortness of breath. A provisional diagnosis of ethanol-related compensated chronic liver disease (CLD) with portal hypertension and splenomegaly, gross ascites with bilateral hepatic hydrothorax was made. The left-sided pleural effusion subsided after three pleural taps, but the right-sided effusion kept refilling even after four to five days of repeated therapeutic taps, so a pigtail catheter was left in situ. The pleural fluid was sent for culture which did not grow any pathogenic organisms. Cartridge-based nucleic acid amplification tests where complex (MTBC) was not detected, Ziehl-Neelsen staining was done in which acid-fast bacilli were not seen, and cytology was done where no malignant cells were seen. The patient was discharged with the pigtail in situ on the right side and, after 20 days, the patient again presented with shortness of breath, and imaging revealed moderate right-side pleural effusion. Draining of pleural fluid was done and sent for investigation which again revealed no infective etiology. The patient was admitted to the hospital for one month as the right-sided effusion did not resolve. Suddenly, the patient developed shortness of breath, and a chest X-ray was done, which showed pigtail blockage; pigtail flushing was done, and the bag was drained. The patient was empirically started on IV meropenem 500 mg TID, IV teicoplanin 400 mg BD, and inj polymyxin B 500,000 IU IV BD. The pleural fluid was sent continuously for investigation for the first two months which again did not reveal any infective etiology. After two months of pigtail in situ, the pleural fluid was sent for CBNAAT where MTBC was not detected, and ZN stain showed smooth acid-fast bacilli. The sample was cultured, and it grew acid-fast bacilli in 72 hours on blood agar, MacConkey agar, and Lowenstein-Jensen media. A line probe assay done from the isolate revealed it to be subsp. abscessus which was resistant to macrolides and sensitive to aminoglycosides. subsp. abscessus was isolated from repeated cultures of pleural fluid, and the patient was advised on a combination treatment of amikacin, tigecycline, and imipenem. The patient was discharged with the indwelling pigtail with the advised treatment; unfortunately, we lost patient follow-up as the patient never returned to us.
PubMed: 38832176
DOI: 10.7759/cureus.59626 -
Infection and Drug Resistance 2024Urinary tract infections exert a significant negative impact on an individual's quality of life and cause significant economic and public health burdens. Therefore, this...
PURPOSE
Urinary tract infections exert a significant negative impact on an individual's quality of life and cause significant economic and public health burdens. Therefore, this study was conducted to identify the common bacterial uropathogens associated with urinary tract infections in Wad Medani patients and their susceptibility to antibiotics.
PATIENTS AND METHODS
This was a cross-sectional study. All urine samples were collected from patients at Wad Medani and investigated at the Pathology Center for Diagnosis and Research, Faculty of Medicine, University of Gezira, Sudan, from the 1st of January 2021 to the 15th of October 2023.
RESULTS
A total of 2698 urine samples were analyzed during the three years study period, with a mean age of 45.29 ± 18.9 years. Among these patients, 1108 (41.8%) were positive for bacterial growth, and 888 (80.14%) were female. A total of 522 (47.1%) were gram positive bacteria (GPB), and 586 (52.9%) were gram negative bacteria (GNB). The most frequently isolated bacteria were 42% (465/1108) and 38.5% (427/1108), while was less detected 3.4% (38/1108). Amikacin 91.5% was the most sensitive drug to isolated GPB, while cotrimoxazole 20.9% was the least sensitive drug. In particular, amikacin 94.1% (144/153) was the most sensitive drug to , while cotrimoxazole 20.7% (80/386) was the least sensitive drug. Moreover, amikacin 91.5% was the most sensitive drug to the isolated GNB, while ampicillin 5.7% was the least sensitive drug. Notably, amikacin was the most sensitive drug to all the isolated GNB, and ampicillin was the least sensitive drug to all the isolated GNB.
CONCLUSION
This study reported a moderate uropathogen isolation rate of 41.8%. and were the most frequently isolated bacteria, most of which were from female patients. Remarkably, amikacin was the most sensitive drug to isolated GNB and GPB.
PubMed: 38828377
DOI: 10.2147/IDR.S464501