blaAmpC Genes Research Articles

Molecular study of Klebsiella pneumoniae antibiotic resistance genes isolates from wound infections

K. pneumoniae, which produces Carbapenemases, is of public health importance because of its resistance to antimicrobials. K. Pneumoniae is identified phenotypically by its large pink mucus appearance on MacConkey agar because of lactose fermentation and by bacteriological, microscopic, and biochemical tests using the VITK 2 device. Antimicrobial susceptibility testing was performed by Kirby-Bauer disc diffusion. Klebsiella pneumoniae represented 5.3% (n = 16). It is highly resistant to antibiotics used to treat wound infections and shows the highest rate of resistance with cefepime 11(68.8%), followed by Ertapenem 9(56.3%), Doripenem and Imipenem 7(43.8%), and Meropenem 6(37.5%). Carbapenemases resistance was identified by phenotype through the Hodge test and also detection of Carbapenemases genes by polymerase chain reaction. The results showed the presence of the bla SHV 16 gene (100%) in K. pneumoniae isolates. The results showed that there were 4 isolates (25%) positive for the bla AMPC gene. The results also showed the presence of the bla KPC gene in two isolates (12.5%). The bla GES gene was not found in K. pneumoniae isolates. In general, the isolates were resistant to carbapenem and cefepime antibiotics. Five random samples were examined by publishing the results of the sequence analysis by BLAST in (NCBI) and the Mega 7 polymorphism detection program: it was found that there was no difference between the sequences, but rather the match was with the bacterium Klebsiella pneumoniae.

Molecular analysis of ESBL- and AmpC-producing Enterobacteriaceae in fecal samples from broiler and backyard chickens

ObjectiveTo analyse the molecular profile of antibiotic resistance in Enterobacteriaceae isolates from fecal samples of healthy broilers and backyard chickens in Tamil Nadu, India. MethodsA total of 115 and 57 bacterial strains were isolated from fecal samples of broiler and backyard chickens, respectively using conventional bacterial culture tests. Bacterial isolates were screened for antibiotic susceptibility by Kirby-Bauer’s disk diffusion method. Colistin susceptibility was tested using the broth microdilution method. Extended-spectrum β-lactamase (ESBL), AmpC β-lactamase and metallo-β-lactamase (MBL) producers were screened by combination disk method. The drug-resistant genes’ positivity was analysed by polymerase chain reaction (PCR) method. ResultsEscherichia coli was the predominant bacterium isolated from both broiler (53%) and backyard (64.9%) chickens. Bacterial isolates from broilers and backyard chickens showed 100% resistance to ampicillin, piperacillin, and piperacillin-tazobactam. Five bacterial isolates from broiler chickens were resistant to colistin. ESBL producers were 34.7% in broilers and 19.1% in backyard chickens. AmpC production was detected in 44.3% of the isolates from broilers and 26.2% of those from backyard chickens. Molecular analysis revealed that bacterial isolates from broiler chickens were positive for drug-resistant genes such as blaTEM (25%), blaSHV (5%), blaCTX-M (4%), blaAmpC (56%), integron (39%), sul1 (30%), and sul2 (23%). Bacterial isolates from backyard chickens were positive for the blaTEM (22%), blaSHV (14%), blaAmpC (54.3%), and integron (20%) genes. None of the isolates from either broiler or backyard chickens harboured New Delhi metallo-β-lactamase (blaNDM) or colistin-resistant genes (mcr-1 to −3). ConclusionsBacterial isolates from broiler chickens harboured a higher number of drug resistance genes, especially blaTEM, blaCTX-M, sul1, sul2, and integron, than those from backyard chickens.

Evaluation of in-feed supplementation of formic acid and thymol as non-antibiotic growth promoters and assessing their effect on antimicrobial resistant E.coli isolated in Turkey.

With the rampant usage of antibiotics as growth promoters (AGPs) in poultry sector, there has been alarming concerns of antimicrobial resistant microbes such as Escherichia coli. Diversification of poultry farming due to consumer demand for safer products with higher protein content, turkey production is gaining popularity. Feed additives such as formic acid (FA) and thymol (TH) are effectively replacing AGPs due to their antimicrobial action. This directed the researchers to find alternatives to antibiotics such as thymol and formic acid because of their strong antimicrobial, anti-oxidative, digestive-stimulating properties. To assess the efficacy of FA and TH as growth promoters and their effect on the antimicrobial resistance (AMR) load, the current study (0-12 weeks) was conducted in CARI VIRAT turkey poults (n = 256; unsexed) those were randomly distributed into eight treatment groups: control(T1), AGP (T2), graded levels of FA (T3 to T5) @ 2.5, 5 and 7.5ml/kg and TH (T6 to T8) @ 120, 240 and 350mg/kg. Cloacal swab samples were collected at 0, 4th, 8th and 12th week interval and processed further for isolation, identification and assessment of resistance profile of E. coli. The final body weight, cumulative gain and FCR were significantly (p < 0.05) better for birds under supplementation. The Total plate count (TPC) and coliforms showcased a significant (p < 0.001) reduction in the FA and TH supplement groups as compared to control and AGP group. The resistance profile indicated E. coli isolates from AGP group with significantly (p < 0.001) highest resistivity against antibiotics (viz. chloramphenicol, tetracycline, nalidixic acid, chlortetracycline) while isolates from FA (T5) and TH (T8) groups were the least resistant. blaAmpC gene was significantly (p < 0.001) harbored in T2 isolates whereas least detected in T5 and T8. It was inferred that formic acid (7.5ml/kg) and thymol (360mg/kg) can effectively replace AGPs and lower AMR burden in poultry.

Study of Antibiotic Resistance in ESKAPE Bacteria Using β-lactamase and ESBL Genes

Background: Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species, collectively known as ESKAPE bacteria, pose a significant threat in healthcare settings due to their increasing antibiotic resistance. Understanding the mechanisms underlying their resistance is crucial for developing effective therapeutic strategies. Methods: This study aimed to investigate the phenotypic and genotypic properties of β-lactamase enzymes in ESKAPE bacteria isolated from ulcer infections. Clinical specimens were collected from patients with various ulcer diseases, and bacterial isolates were identified using standard bacteriological methods and the Vitek-2 automated system. DNA extraction, polymerase chain reaction (PCR), and antibiotic susceptibility testing using the Kirby-Bauer disk diffusion method were performed. The presence of specific β-lactamase genes (blaKPC, blaTEM, blaCTX-M, and blaAMPC) was examined through molecular techniques. Results: Among the 104 clinical specimens collected, 88% yielded positive cultures, with Gram-negative bacteria predominating. Antibiotic susceptibility testing revealed high resistance rates, particularly to β-lactam antibiotics, among ESKAPE isolates. Molecular analysis identified the presence of extended-spectrum β-lactamases (ESBLs) in all isolates, with blaKPC and blaTEM being the most prevalent β-lactamase genes. Notably, blaKPC was detected in 72% of E. cloacae, 13.3% of S. aureus, 33.33% of Klebsiella pneumoniae, 50% of Pseudomonas aeruginosa, 0% of E. faecium, and 100% of A. baumannii isolates. Similarly, blaCTX-M and blaAMPC genes showed distinct distribution patterns across the different species. Conclusion: The study highlights the widespread presence of ESBL-producing ESKAPE bacteria in ulcer infections and underscores the importance of molecular techniques for accurate detection of β-lactamase production.

Prevalence of antibiotic resistance genes of Escherichia coli at the pig slaughterhouses in the Mekong Delta

The study was conducted to determine the antimicrobial susceptibility and antibiotic-resistance genes of Escherichia coli at the pig slaughterhouses in the Mekong Delta, Vietnam. A total of 60 samples were collected at the slaughterhouse in the Mekong Delta, including 24 feces, 24 carcasses, 8 floors, and 4 wastewater samples. The prevalence of E. coli in feces, wastewater, carcasses, and floor samples was 91.67%, 50.00%, 29.17%, and 25.00%, respectively. A total of 79 E. coli isolates were examined for antimicrobial susceptibility to 15 antibiotics using the disc diffusion method according to CLSI 2021 guidelines. E. coli strains were highly resistant to amoxicillin (83.54%), ampicillin (78.48%), streptomycin (63.29%), and florfenicol (63.29%). However, those E. coli strains were sensitive to amoxicillin + acid clavulanic and amikacin (97.47%), cefaclor (95.45%), cefuroxime (93.67%), and enrofloxacin (92.41%). The results showed that 96.2% of examined E. coli strains were resistant from one antibiotic to eight antibiotics, and the most frequent multidrug-resistance phenotype was amoxicillin + ampicillin + florfenicol + streptomycin (13.92%). The prevalence of antibiotic resistance genes (strA, sulII, qnrA, tetA, blaampC, blaTEM, and blaCTX-M) in E. coli was determined by PCR. The prevalence of strA, sulII, qnrA, tetA, blaampC, and blaTEM genes in E. coli strains was 75.67%, 72.97%, 75.67%, 83.78%, 91.89%, and 83.78% respectively; however, blaCTX-M gene was not detected. Therefore, the contamination of E. coli exhibiting antibiotic resistance in pig slaughterhouses should be controlled to prevent public health.

The Aminoglycoside Resistance Genes, pehX, blaCTXM, blaAmpC, and npsB among Klebsiella oxytoca Stool Samples

Background: Klebsiella oxytoca may cause various infections, including respiratory, urinary, and bloodstream infections, often with multidrug-resistant strains posing challenges in treatment. The aim of this study was for molecular identification of K. oxytoca and to assess the existence of aminoglycoside resistance genes in biofilm and in toxin-producing and AmpC-positive isolates. Methods and Results: A total of 400 non-duplicate stool samples were collected from patients with colitis from 2019 to 2020 and were immediately cultured onto McConkey and blood agar (Merk, Germany). Antibiotic discs and Mueller-Hinton agar (MHA) culture medium (Merck, Germany) were used for antimicrobial susceptibility testing. The disk diffusion was done for susceptibility examination of them using CLSI 2020. Phenotypic detection of AmpC enzymes and biofilm formation were also determined. The PCR was performed to detect polygalacturonase (pehX) gene, blaCTX-M gene, npsB toxin-encoding gene, blaAmpC gene, and the aac(6′)-lb and aac(3′)-IIa AMEs genes. A total of 100 K. oxytoca were identified from stool samples. Most isolates were not susceptible to tetracycline, cotrimoxazole, or cefoxitin disks. Moreover, most were susceptible to amikacin and piperacillin-tazobactam disks. Among 100 isolates, 54% produced the AmpC enzyme in the combined disk method. Among them, 30 isolates were resistant to gentamicin. Strong biofilm formation was determined in 66% of isolates, and 30% of them produced moderate biofilms. Moreover, 4% of the isolates had weak biofilms. Among the 60 gentamicin-resistant K. oxytoca, 32 isolates had strong biofilms, and 11 isolates produced moderate ones. The pehX was used for the molecular identification of K. oxytoca; the results showed the presence of this gene in all isolates. The majority (98%) of K. oxytoca amplified the npsB toxin-encoding gene. The rate of blaCTX-M, blaAmpC, aac(6′)-lb, and aac(3)-IIa genes were 62%, 45%, 12%, 24%, respectively. Conclusion: In our study, more than half of K. oxytoca showed MDR phenotype. Moreover, half of the isolates carried the blaAmpC and blaCTX-M genes. Strong biofilm formation was observed in more than 60% of them.

Phenotypic and genotypic characteristics of beta-lactamase dominant with CARBA, AmpC, and ESBL-producing bacteria in municipal wastewater influent in Helsinki, Finland

Analysing samples of municipal wastewater influent (before treatment) can help to map the status of antibiotic-resistant bacteria (ARB) at the population level in sewershed communities and may also help in predicting the public health risks of ARB in surface water because of the outfall of wastewater. In this study, we investigated the bacterial isolates carrying beta-lactamase genes in wastewater and compared their genotypic and phenotypic characteristics. A total of 399 bacterial isolates grown on CHROMagarESBL (n=207) and CHROMagarKPC (n=192) from composite wastewater influent samples (n=7) from the Viikinmäki wastewater treatment plant (Helsinki) were subcultured, nucleic acid was extracted, and the prevalence of different beta-lactamase genes was screened with multiplex polymerase chain reaction (PCR). All PCR-positive isolates were identified with MALDI-TOF. A total of 32.6% of isolates (130 of 399) were PCR positive for at least one resistance gene, and 13% of these positive isolates out of 130 had at least three resistance genes. Among the 22 detected genes, blaGES group was the most prevalent, at 25.8% (n=198; many isolates carried multiple genes), followed by blaMOX (13.1%) and blaTEM (10.1%) as most frequently detected. Furthermore, out of 18 different bacterial species/genera detected as carrying beta-lactamase genes, A. hydrophila/caviae (28.5%), Enterobacter spp. (16.9%), and E. coli (14.6%) were the most prevalent. Enterobacter spp., Aeromonas spp., and K. cryocescens potentially carried AmpC genes, and E. coli carried ESBL genes. We recorded a huge variety of beta-lactamases (blaAmpC, blaESBL, and blaCARBA) genes in many potential pathogens that probably originated from both enteric and environmental sources.

Virulence potential of multidrug-resistant Acinetobacter baumannii isolates from COVID-19 patients on mechanical ventilation: The first report from Serbia.

Since the WHO declared the COVID-19 pandemic in March 2020, the disease has spread rapidly leading to overload of the health system and many of the patients infected with SARS-CoV-2 needed to be admitted to the intensive care unit (ICU). Around 10% of patients with the severe manifestation of COVID-19 need noninvasive or invasive mechanical ventilation, which represent a risk factor for Acinetobacter baumannii superinfection. The 64 A. baumannii isolates were recovered from COVID-19 patients admitted to ICU at General Hospital "Dr Laza K. Lazarević" Šabac, Serbia, during the period from December 2020 to February 2021. All patients required mechanical ventilation and mortality rate was 100%. The goal of this study was to evaluate antibiotic resistance profiles and virulence potential of A. baumannii isolates recovered from patients with severe form of COVID-19 who had a need for mechanical ventilation. All tested A. baumannii isolates (n = 64) were sensitive to colistin, while resistant to meropenem, imipenem, gentamicin, tobramycin, and levofloxacin according to the broth microdilution method and MDR phenotype was confirmed. In all tested isolates, representatives of international clone 2 (IC2) classified by multiplex PCR for clonal lineage identification, bla AmpC, bla OXA-51, and bla OXA-23 genes were present, as well as ISAba1 insertion sequence upstream of bla OXA-23. Clonal distribution of one dominant strain was found, but individual strains showed phenotypic differences in the level of antibiotic resistance, biofilm formation, and binding to mucin and motility. According to PFGE, four isolates were sequenced and antibiotic resistance genes as well as virulence factors genes were analyzed in these genomes. The results of this study represent the first report on virulence potential of MDR A. baumannii from hospital in Serbia.

Detection of beta-lactam antibiotic resistance in aquatic Enterobacteriaceae isolates

Abstract Production of the beta-lactamase enzymes is the primary resistance mechanism caused by unconcious consumption of the beta-lactam group of antibiotics in Enterobacteriaceae. Combined disc tests were performed for extended-spectrum beta-lactamase (ESBL) confirmation (n = 15) and class C beta-lactamase (AmpC) confirmation (n = 6) after the disc diffusion test was applied in a total of 27 Enterobacteriaceae strains from Western Black Sea, Lake Manyas and Lake Iznik. Plasmid-mediated blaTEM, blaSHV, blaCTX-M , blaIMP genes, CIT, MOX, FOX gene groups and chromosomal blaAmpc gene of E. cloacae were investigated using the polymerase chain reaction (PCR). Three E. coli strains were shown to produce ESBL, while one E.coli and three E. cloacae strains were confirmed for AmpC production by disc tests. blaTEM (n = 2), blaSHV (n = 4), blaCTX-M (n = 2), blaTEM + blaSHV (n = 1), blaCTX-M + CIT (n = 1), blaSHV + CIT (n = 1) genes and/or gene groups were detected in 11 E. coli isolates; while blaSHV (n = 3) was observed in three Klebsiella strains (two K. oxytoca and one K. pneumoniae). With this study, the aquatic environments of Turkey were proved to be the reservoirs of antibiotic-resistance determinants of plasmid-mediated beta-lactamases in environmental wild-type bacteria transmitted by horizontal gene transfer.

Detection of Extended-spectrum Beta-lactamases (ESBLs), Carbapenemase, Metallo-β-lactamase Production Bacteria and Antibiotic Susceptibility Pattern in Hospitalized Patients with Ventilator-associated Pneumonia

Background: Due to the increase in microbial resistance, nosocomial multidrug resistance infections, including ventilator-associated pneumonia (VAP), are presently one of the main causes of death in hospitals since they are difficult to treat. Objectives: This study aimed to investigate the bacterial etiology of VAP and their microbial resistance pattern in Dezful Hospital, southwest of Iran. Methods: In this cross-sectional study, 131 bacterial isolates were isolated from the respiratory secretions of the patients with VAP in ICU wards. Antibiotic susceptibility testing (AST) of all isolates was carried out after the identification. Then the extended-spectrum beta-lactamases (ESBLs), carbapenemase, and metallobetalactamase were identified by phenotyping and genotyping. Results: The most frequent isolates were Staphylococcus aureus (30.5%), Acinetobacter baumannii (25.2%), and Klebsiella pneumoniae (24.4%). All strains of S. aureus were sensitive to vancomycin, ticoplanin, quinupristin-dalfopristin, and linezolid. Escherichia coli and Klebsiella showed high resistance to cephalosporins. More than 93% of Acinetobacter isolates were resistant to carbapenem and quinolones. The overall prevalence of ESBLs and carbapenemase producing bacteria were 80.43% and 73.6%, respectively. The most frequent ESBLs gene was blaCTX-M gene (78.3%) followed by blaAMP-C gene (67.5%), blaSHV gene (64.8%), and blaTEM gene (54%). Conclusions: In sum, there was a possibility that the treatment of nosocomial multidrug resistant infections such as VAP would become a major challenge. Therefore, it was recommended that AST results should always be considered when selecting the appropriate treatment regimen. Furthermore, it was found important to emphasize the principles of antibiotic stewardship and to constantly monitor the pattern of microbial susceptibility.

Molecular characteristics of global β-lactamase-producing Enterobacter cloacae by genomic analysis

ObjectiveTo analyze the characteristics of global β-lactamase-producing Enterobacter cloacae including the distribution of β-lactamase, sequence types (STs) as well as plasmid replicons.MethodsAll the genomes of the E. cloacae were downloaded from GenBank. The distribution of β-lactamase encoding genes were investigated by genome annotation after the genome quality was checked. The STs of these strains were analyzed by multi-locus sequence typing (MLST). The distribution of plasmid replicons was further explored by submitting these genomes to the genome epidemiology center. The isolation information of these strains was extracted by Per program from GenBank.ResultsA total of 272 out of 276 strains were found to carry β-lactamase encoding genes. Among them, 23 varieties of β-lactamase were identified, blaCMH (n = 130, 47.8%) and blaACT (n = 126, 46.3%) were the most predominant ones, 9 genotypes of carbapenem-hydrolyzing β-lactamase (CHβLs) were identified with blaVIM (n = 29, 10.7%) and blaKPC (n = 24, 8.9%) being the most dominant ones. In addition, 115 distinct STs for the 272 ß-lactamase-carrying E. cloacae and 48 different STs for 106 CHβLs-producing E. cloacae were detected. ST873 (n = 27, 9.9%) was the most common ST. Furthermore, 25 different plasmid replicons were identified, IncHI2 (n = 65, 23.9%), IncHI2A (n = 64, 23.5%) and IncFII (n = 62, 22.8%) were the most common ones. Notably, the distribution of plasmid replicons IncHI2 and IncHI2A among CHβLs-producing strains were significantly higher than theat among non-CHβLs-producing strains (p < 0.05).ConclusionAlmost all the E. cloacae contained β-lactamase encoding gene. Among the global E. cloacae, blaCMH and blaACT were main blaAmpC genes. BlaTEM and blaCTX-M were the predominant ESBLs. BlaKPC, blaVIM and blaNDM were the major CHβLs. Additionally, diversely distinct STs and different replicons were identified.

Dissemination and Genetic Relatedness of Multidrug-Resistant and Extensively Drug-Resistant Acinetobacter baumannii Isolates from a Burn Hospital in Iraq.

Acinetobacter baumannii is an aggressive opportunistic bacterial pathogen that causes severe nosocomial infections, especially among burn patients. An increasing number of hospitals-acquired infections have been reported all over the world. However, little attention has been paid to the relatedness between A. baumannii isolates from different hospital environments and patients. In this study, 27 isolates were collected from the Burn and Plastic Surgery Hospital of Al Sulaymaniyah City, Iraq, from January through December 2019 (11 from patients and 16 from the wards environment), identified to species level as A. baumannii using Vitek 2 system and molecular detection of 16S rRNA gene, and then confirmed by targeting the blaOXA-51 gene. Moreover, the isolates were characterized by means of automated antimicrobial susceptibility assay, antimicrobial-resistant patterns, a phenotypic method using a combined disk test, and molecular methods for the detection of class A and C β-lactamase genes, and finally, the genetic relatedness was classified. Antimicrobial susceptibility testing showed that 63% (17/27) of the retrieved A. baumannii isolates were extensively drug-resistant to 8/9 antimicrobial classes. Furthermore, 37% (10/27) of the isolates were classified as multidrug-resistant; 8 isolates exhibited similar resistant patterns and the other two isolates showed 2 different patterns, while resistance was greater in isolates from patients than from the ward environment. Combined disk test showed that two isolates contained extended-spectrum β-lactamase. All isolates carried blaTEM-1, and two copies of the blaCTX-1 gene were indicated in one isolate, while blaSHV was absent in all isolates. Twenty-four isolates carried the blaAmpC gene; among them, 3 isolates harbored the insertion sequence ISAba-1 upstream to the gene. Using Enterobacterial Repetitive Intergenic Consensus PCR, the isolates were clustered into 6 distinct types; among them, two clusters, each of four strains, were classified to contain isolates from both patients and environments. The clusters of similar genotypes were found in inpatients as well as the environments of different wards during time periods, suggesting transmission within the hospital. Identification of possible infection sources and controlling the transmission of these aggressive resistance strains should be strictly conducted.

Prevalence of High-Risk β-Lactam Resistance Genes in Family Livestock Farms in Danjiangkou Reservoir Basin, Central China.

The propagation of antibiotic resistance genes (ARGs) from domestic livestock manure is an unnegligible important environmental problem. There is an increasing need to understand the role of domestic livestock manure in causing antibiotic resistance in the environment to minimize risks to human health. Here, we targeted β-lactam resistance genes (bla genes), primarily discovered in clinical settings, to compare the high-risk ARG profile and their main spreading vectors of 26 family livestock farms in China and analyze the effects of domestic livestock manure on their receiving farmland environments. Results showed that the high-risk bla genes and their spreading carriers were widely prevalent in livestock and poultry manure from family farms. The blaampC gene encoding extended-spectrum AmpC β-lactamases, as well as its corresponding spreading carrier (class-1 integron), had the highest occurrence level. The bla gene abundance in family chicken farms was higher than that in family swine and cattle farms, while the bla gene contamination in the feces of laying hens or beef cattle was worse than that in corresponding broiler chickens or dairy cattle. Notably, the application from domestic livestock manure led to substantial emission of bla genes, which significantly increased the abundance of high-risk resistance genes in farmland soil by 12–46 times. This study demonstrated the prevalence and severity of high-risk resistance genes in domestic livestock and poultry manure; meanwhile, the discharge of bla genes also highlighted the need to mitigate the persistence and spread of these elevated high-risk genes in agricultural systems.

Characterization of Extended Spectrum Beta Lactamase Producing Escherichia coli from Calves

Background: Cephalosporins are major antimicrobials used to treat serious infections. However, their effectiveness is being compromised by the emergence of extended spectrum beta lactamases (ESBL). The present study was aimed to characterize ESBL producing Escherichia coli from healthy and diarrheic cattle calves. Methods: A total of 52 rectal swabs were collected from healthy and diarrheic cattle calves between August 2019 to March 2020. Phenotypically E. coli were characterized based on morphology, microscopy and biochemical tests. Extended Spectrum Beta Lactamases (ESBL) E. coli initial screening was performed by using cefpodoxime, ceftazidime, cefepime and aztreonam antibiotics. The confirmation of the ESBL producing strains was conducted through ESBL phenotypic identification kit and double disc diffusion test (DDDT). Molecular characterization of ESBL E. coli was conducted by PCR amplification of blaCTX-M, bla TEM and bla AmpC genes. Plasmid profiling of the ESBL E. coli isolates was carried out. Result: Phenotypically, out of the 51 E. coli isolated, 05 (9.8%) E. coli isolates were confirmed as ESBL strains. PCR amplification revealed 01 (20%), 04 (80%) and 03 (60%) isolates positive for blaCTX-M, bla TEM and bla AmpC genes, respectively. Plasmid profiling of the isolates showed that 60% isolates were harboring plasmids of varying size and number. The plasmid number among the isolates ranged from 0-4 plasmids per isolate and plasmid size varied from 900bp to greater than 10kb. The relatively high rates of ESBL producers in diarrheic calves were found than healthy calves. The study highlights the existence of ESBL producing E. coli isolates with certain strains carrying mobile genetic elements in livestock and probable disseminators of resistance, thus imposing public health threat.

First Record of Dissemination of BLBLI-Resistant Enterobacter cloacae from Public Hospitals in Baghdad, Iraq

Background: Enterobacter cloacae are most frequently isolated from human clinical specimens. Objective: This cross-sectional study aimed to investigate the dissemination of E. cloacae clinical isolates resistant to β-lactam-β-lactamase inhibitor (BLBLI) combinations from different clinical specimens of hospitalized patients. Methods: E. cloacae isolates were recovered from different clinical samples of hospitalized patients in three main hospitals in Baghdad city. E. cloacae isolates were identified based on their morphology and biochemical tests, and the identification was confirmed using Vitek-2 system. The antibiotic susceptibility testing of E. cloacae isolates to a variety of antibiotics was achieved using disc diffusion test (DDT) and Vitek-2 system. Results: Results found that among 335 culture-positive samples, 30 isolates (8.9%) belonged to E. cloacae. A high rate of isolation was observed in urine isolates (46.6%), followed by wounds (burns) isolates (26.6%). Out of 30 E. cloacae strains isolated during this study, 18 (60%) showed reduced susceptibility to BLBLI combinations. TEM genes (TEM-1 and TEM-2) were successfully amplified from 7/18 isolates (38.8%) and high rate of BLBLI genes was detected (CTX-M, bla-SHV, SHV-2, and OXA-1). However, no BLBLI genes of bla-AmpC, bla- OXA-2, and bla- OXA-10 were found in E. cloacae isolates when tested using specific primers for bla-AmpC and bla-OXA genes. Conclusion: From this study, we can conclude that the production of inhibitor-resistant β-lactamases by E. cloacae isolates could be increasingly common in nosocomial pathogens other than E. coli or K. pneumoniae in public hospitals in Baghdad, Iraq.

Evaluation of antibiotic resistance and prevalence of multi-antibiotic resistant genes among Acinetobacter baumannii strains isolated from patients admitted to al-yarmouk hospital

Emerging antibiotic resistance in microorganisms particularly multidrug-resistant strains among bacteria are increasing because of misusing antibiotics as well as evolution of antibiotic resistance mechanisms. In this regard, Acinetobacter baumannii is one of the six most common multidrug-resistant microorganisms in hospitals. Recently, carbapenems, as common antibiotics to treat infections of Acinetobacter have not an acceptable efficiency because of the resistance emergence to these antibiotics in many strains. In this study, resistant strains of A. baumannii were isolated and identified as an appropriate preventive strategy to reduce infections in hospitals. Disc diffusion test and PCR method were used to isolate of resistant strains and identify beta-lactamase genes of blaAmpC, blaTEM, blaVIM, and blaSHV. This study showed that these genes were contributed in antibiotic resistance with about 18.4% and ≥53.5% strains expressing all 4 genes and ≥3 genes, respectively. The blaAmpC gene is more prevalent than other genes, and this is probably due to the prevalence or rapid transfer of this beta-lactamase. However, more studies should be performed in a comparative way to isolate and identify other antibiotic-resistant bacterial strains relate to other hospitals.

Epidemiology and high incidence of metallo-β-lactamase and AmpC-β-lactamases in nosocomial Pseudomonas aeruginosa.

Objective(s):Isolates producing metallo-β-lactamase (MBL) have a significant impact on therapeutic and diagnostic layouts, plus their increased frequency has been reported globally. Determination of incidence of clinical isolates of Pseudomonas aeruginosa that are capable of producing MBL and AmpC-β-lactamases making them resistant to imipenem and cefoxitin. Materials and Methods:Out of 1159 collected samples of urine, wound swabs, blood, tissue, and pus, the isolation rate of P. aeruginosa in the period of March 2020 to February 2021 was 22.0% (255/1159). Bacterial strains that were resistant towards imipenem were further processed for detecting the β-lactamase group of genes followed by statistical analysis of risk factors done based on clinical sample, gender, plus department of sample collection. Results:The percentage of resistance against imipenem was found to be 53%. Out of 135 strains, phenotypic tests revealed MBLs incidence to be 61.5% by combination disc test and 81.5% by Modified Hodge test (MHT). Frequencies of blaIMP-1, blaVIM, blaSHV, blaTEM, and blaOXA genes were calculated to be 13%, 15%, 32%, 43%, and 21%, respectively. Co-expressions of blaMBLs (blaVIM and blaIMP-1) plus blaESBL (blaSHV, blaOXA, blaTEM) were detected using simplex and multiplex PCR. blaTEM, blaSHV, and blaOXA co-existed in 7.5% of clinical isolates. 5.5% of the isolates exhibited simultaneous expression of MBL/ESBL genes. 15% of the isolates resistant to cefoxitin were positive for the blaAmpC gene (17/114).Conclusion: This is a pioneer report from Pakistan that concomitantly presents expression of blaVIM and blaIMP-1 with blaTEM, blaOXA, blaSHV, and blaAmpC in isolates of P. aeruginosa.

Molecular Detection of Ampicillin Resistant Genes in E. coli Isolates from ‎Dogs in India

The most common cause of urinary tract infection in dogs is uropathogenic Escherichia coli (UPEC). This condition often presents with vaginal discharge, dribbling of urine, straining or vocalization while urinating due to pain. Furthermore, the following signs are also noticeable: hematuria, lethargy, proteinuria, dysuria, cystitis, and oliguria. The aim of this research was to investigate the genes of ampicillin resistance in E. coli isolates from dogs with urinary tract infections. Out of 103 urine samples cultured (Blood agar, MacConkey’s lactose agar and Eosin methylene blue agar), 24.3% were positive for uropathogenic Escherichia coli. The positive isolates were further subjected to antimicrobial sensitivity test and PCR analysis. All the uropathogenic Escherichia coli isolates were resistant to ampicillin while 96% were resistant to Cloxacillin and Oxytetracycline. Susceptibility to Meropenem, Gentamicin and Amikacin were 64 %, 44 % and 40% respectively. All the 25 strains of the E. coli were identified to be resistant to two or more antibiotics. The PCR result showed the presence of blaAMPC in all the samples and 60 % had blaTEM genes responsible for ampicillin resistance. However, none of the isolates were positive for the blaSHV gene.The presence of the blaAMPC and blaTEM genes in the dogs studied resulted in ampicillin resistance, with blaAMPC being the most commonly detected ampicillin gene in Escherichia coli in the study area. Meropenem was also found to be a good choice for treating uropathogenic E. coli infection in dogs.

Multi-drug resistant Aeromonas species in Annelida: An evidence of pathogen harbouring leech in recreation water nexus of Oghara Nigeria environs

Aeromonas infections have shown diverse complications in management due to the multiple antibiotic resistance observed amongst its members. The origin and habitat of its resistance development yet remain vague. The present study depicts Leech and its infested recreational water as a reservoir of multidrug-resistant Aeromonas hydrophila. Skin swabs of recreational water bathers before (Bb)/after bathing (Ab) (250 each) and 250 leeches (Hirudomedicinalis) were collected from recreational water sites. Standard Microbiological and Molecular biology methods were applied for isolation and characterization. Two hundred and forty-five (98%)Bb specimen, showed a negative growth oforganisms, 84% (210) of the Ab specimen harboured presumptive Aeromonas species, while 100% (250) Leeches specimen harboured Aeromonas species. The Polymerase Chain Reaction (PCR) of 16SrRNA gene detection confirmed all (465/100%) isolates as Aeromonas species while 13.6% (63) were further delineated as Aeromonas hydrophila. The antibiogram showed 45(97.82%) resistance to the β-lactam antibiotic and other antibiotic groups. The PCR detection of resistant markers, virulent and plasmid profile of isolates reveals conjugative plasmid mediation, lip (123/97.6%), act (104/82%), hhly (93/73%) genes and BlaampC gene, BlaTEM, gene and BlaSHV gene. Observation of pathogens with similar multiple antibiotic-resistant gene-profile both in the bathers'skin swab and gut of leeches indicates origin/habitat, association and suggests the gut of leeches as breeding habitat for the pathogen. This is an emerging public health concern that associates specifically the environment and human superficial infections.

Molecular Exploring of Plasmid-mediated Ampc beta Lactamase Gene in Clinical Isolates of Proteus mirabilis

Between September to December 2020, thirteen isolates of Proteus mirabilis were recovered among one hundred fifty; MacConkey agar was utilized to purify Gram-negative bacteria isolated from infections of the urinary tract. The primary identification of Proteus mirabilis isolates was relied on “colonial morphology, microscopic examination, and biochemical “tests; however, the confirmation of identification of antimicrobial susceptibility of isolates was conducted utilizing an automated VITEK-2 compact system. The result showed that Proteus mirabilis isolates were highly resistant to most antibiotics, making them multi-drug resistant (MDR). Phenotype methods were used to detect AmpC beta-lactamase. Initial and confirmatory methods showed that eight isolates were AmpC producers. Polymerase Chain Reaction (PCR) was employed to detect the blaampC gene.