Multiple Antibiotic Resistance Index Values Research Articles

Genotyping and Molecular Characterization of Extended-Spectrum Beta-Lactamases-Producing Uropathogenic Escherichia Coli in and Around Coimbatore District, Tamil Nadu, India

Background: Escherichia coli, an extraintestinal flora, develops virulence traits through a persistent encounter with host and constant exposure to antibiotics, which makes it line up as the most common urinary pathogen. Thus, this study aimed to screen the presence of virulence traits among multidrug-resistant urinary pathogenic E. coli among the urine samples collected from inpatients and outpatients of the multispecialty hospitals. Materials and Methods: Standard microbiological laboratory protocols were followed, and about 210 samples were processed and screened. Results: Among those samples, 114 were reported positive for the presence of uropathogenic E. coli(UPEC). Gender-wise distribution was found to be more among female patients (56%) than male patients (51%). During screening for hemolytic activity, 37% of test isolates were α hemolytic, 48% were β hemolytic, and 15% were γ hemolytic. Screening virulence among test isolates, sfa gene (49%), afa (42%), hly (68%), CNF (43%), and aer, accounts for 65%. Further, the multidrug resistance of the isolates was done by using ten antibiotics. All the isolates exhibited the multiple antibiotic resistance (MAR), and the highest percentage of resistance was found against ceftazidime (100%), and the least percentage of resistance was observed against imipenem (2%) followed by amikacin (8%). MAR index values of all the isolates ranged from 0.4 to 1. Conclusion: The presence of various virulence genes and the high degree of resistance among the isolates against the antibiotics used in this study confirm the prevalence of extended-spectrum β-lactamase producers among the UPEC.

Antibiotic Resistance Case Study: Enterobacteriaceae isolated from Batlama Creek in Giresun, Turkey

Enterobacteriaceae were isolated from the freshwater of the Batlama Creek in Giresun, to measure their resistance levels against to antibiotics. A total of 9 antibiotics disc were applied for the resistance test. Antibiotic resistances of all isolates were at percentages for ampicillin (75%), erythromycin (64%), nalidixic acid (48%), tetracycline (39%), amikacin (34%), cefazolin and chloramphenicol (33%), cefuroxime (32%) and cefotaxime (23%), respectively. The highest resistant strain was resistant against to 9 antibiotics, while the weak resistance of 16 isolates were sensitive to all antibiotics. Moreover, Multiple antibiotic resistance index values were found to be higher than 0.2 for 77% of all isolates. High resistances of examined bacteria against to antibiotics indicated a dense and multisource pollution in the Batlama Creek. Consequently, a need for good surveillance programs to monitor antimicrobial resistance patterns in surface water bodies.

Antibiotic and heavy metal resistance of Aeromonas hydrophila and Edwardsiella tarda isolated from red hybrid tilapia (Oreochromis spp.) coinfected with motile aeromonas septicemia and edwardsiellosis.

Aim:The aim of this study is to identify antibiogram and heavy metal resistance pattern of Aeromonas hydrophila and Edwardsiella tarda isolated from red hybrid tilapia (Oreochromis spp.) coinfected with motile aeromonas septicemia and edwardsiellosis in four commercial fish farms.Materials and Methods:A. hydrophila and E. tarda were isolated using glutamate starch phenol red and xylose lysine deoxycholate (Merck, Germany) as a selective medium, respectively. All the suspected bacterial colonies were identified using conventional biochemical tests and commercial identification kit (BBL Crystal, USA). Susceptibility testing of present bacterial isolates to 16 types of antibiotics (nalidixic acid, oxolinic acid, compound sulfonamides, doxycycline, tetracycline, novobiocin, chloramphenicol, kanamycin, sulfamethoxazole, flumequine, erythromycin, ampicillin, spiramycin, oxytetracycline, amoxicillin, and fosfomycin) and four types of heavy metals (mercury, chromium, copper, and zinc) were carried out using disk diffusion and two-fold agar dilution method, respectively.Results:Three hundred isolates of A. hydrophila and E. tarda were successfully identified by biochemical tests. Antibiotic susceptibility testing results showed that 42.2% of the bacterial isolates were sensitive to compound sulfonamides, sulfamethoxazole, flumequine, oxytetracycline, doxycycline, and oxolinic acid. On the other hand, 41.6% of these isolates were resistant to novobiocin, ampicillin, spiramycin, and chloramphenicol, which resulted for multiple antibiotic resistance index values 0.416. Among tested heavy metals, bacterial isolates exhibited resistant pattern of Zn2+ > Cr6+ > Cu2+ > Hg2+.Conclusion:Results from this study indicated that A. hydrophila and E. tarda isolated from coinfected farmed red hybrid tilapia were multi-resistant to antibiotics and heavy metals. These resistant profiles could be useful information to fish farmers to avoid unnecessary use of antimicrobial products in the health management of farmed red hybrid tilapia.

Antibacterial activity of essential oil from lavender (Lavandula angustifolia) against pet turtle-borne pathogenic bacteria

Pet turtles are well-known to harbor an array of bacterial pathogens which can cause zoonotic infections in humans as well as opportunistic infections in the turtles itself. Essential oils are the natural plant extracts which have been traditionally used for disease treatment. In the present study, the essential oil of lavender (EOL) was examined for its antibacterial activity against thirty-eight strains of turtle-borne pathogenic bacteria belonging to seven species; Aeromonas hydrophila, A. caviae, A. dhakensis, Citrobacter freundii, Proteus mirabilis, Salmonella enterica and Pseudomonas aeruginosa. Antibacterial activity of EOL was tested by means of disk diffusion, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) tests. In addition, the antimicrobial susceptibility pattern of 11 commonly used antimicrobials was examined and the multiple antibiotic resistance (MAR) index was calculated. The results revealed that EOL was active against all tested turtle-borne pathogenic bacteria except P. aeruginosa. The range of MIC and MBC values of EOL against isolates except P. aeruginosa were recorded as 0.5–1% (V/V) and 0.5–2% (V/V), respectively. The MBC/MIC ratio was detected as <4, revealing that the tested EOL was bactericidal. Besides, most of the isolates were resistant to different antimicrobials in antimicrobial disk diffusion test. MAR index values of the tested strains were ranging from 0.27 to 0.91. The outcomes indicate that EOL has a potential to be used as an antibacterial agent against pathogenic bacteria isolated from pet turtles.

Prevalence and Antimicrobial Resistance of Enterobacteriaceae in Shell Eggs from Small-Scale Poultry Farms and Farmers' Markets

Public health concerns over the emergence of antimicrobial resistant bacteria have increased recently. The purpose of this study was to investigate the prevalence of antimicrobial resistant Enterobacteriaceae in shell eggs purchased from small poultry farms and farmers' markets. A total of 504 eggs were pooled to make 252 composite samples, consisting of 2 eggs per composite. The microbial quality of shell eggs was determined by standard quantitative, biochemical, and PCR techniques. Susceptibility to 13 antimicrobial agents was determined by the Kirby-Bauer disk diffusion technique, and results were interpreted based on Clinical and Laboratory Standards Institute values. Shell eggs and egg contents were positive for Escherichia coli (11.9 and 5.2%, respectively), Enterobacter (9.1 and 7.9%), and Serratia (11.5 and 4.8%). Salmonella was isolated from 3.6% of egg shells but not from egg contents. Mean (±SD) Enterobacteriaceae levels (4.4 ± 2.0 log CFU per eggshell) on shell eggs from poultry farms was significantly higher (P ≤ 0.05) than that on shell eggs from farmers' markets (2.1 ± 1.3 log CFU per eggshell). Of the 134 isolates recovered, resistance among isolates from farm and market shell eggs to erythromycin was most common (48.5 and 32.8%, respectively) followed by ampicillin (44.8 and 17.2%), and tetracycline (29.9 and 17.2%). The multiple antibiotic resistance index value for E. coli and Pantoea was 0.62, and that for Salmonella and Klebsiella terrigena was 0.08, indicating that Enterobacteriaceae in shell eggs can be resistant to multiple antimicrobial agents. These data reveal that shell eggs from small poultry farms and farmers' markets can harbor antimicrobial resistant pathogenic and commensal bacteria. Thus, failure to properly handle shell eggs poses a potential health hazard to consumers.

Occurrence and patterns of antibiotic resistance in vertebrates off the Northeastern United States coast

The prevalence of antibiotic-resistant bacteria in the marine environment is a growing concern, but the degree to which marine mammals, seabirds and fish harbor these organisms is not well documented. This project sought to identify the occurrence and patterns of antibiotic resistance in bacteria isolated from vertebrates of coastal waters in the northeastern United States. Four hundred and seventy-two isolates of clinical interest were tested for resistance to a suite of 16 antibiotics. Fifty-eight percent were resistant to at least one antibiotic, while 43% were resistant to multiple antibiotics. A multiple antibiotic resistance index value >or=0.2 was observed in 38% of the resistant pathogens, suggesting exposure of the animals to bacteria from significantly contaminated sites. Groups of antibiotics were identified for which bacterial resistance commonly co-occurred. Antibiotic resistance was more widespread in bacteria isolated from seabirds than marine mammals, and was more widespread in stranded or bycaught marine mammals than live marine mammals. Structuring of resistance patterns based on sample type (live/stranded/bycaught) but not animal group (mammal/bird/fish) was observed. These data indicate that antibiotic resistance is widespread in marine vertebrates, and they may be important reservoirs of antibiotic-resistant bacteria in the marine environment.