Isolation,Identification and Antibiotics Susceptibility Test of Citrobacter freundii from Procambarus clarkia

This experiment was conducted to clarify species and drug resistance of pathogen from the diseased Procambarus clarkia. Pathogenic bacteria from hepatopancreas of the diseased P. clarkia were examined using conventional methods,and then were isolated. The further tests and analysis of the isolated strain were developed,including the regression experiment to P. clarkia,the morphology,physiological and biochemical characteristics,sequence analysis of their 16 S rRNA and gyr B genes,and the susceptibility test to antibiotics. Large colonies with similar morphology and color were obtained. Strain X120523 was identified as Citrobacter freundii,proved to have strong pathogenicity,and was susceptible to quinolones and aminoglycosides.

A comparative study on antimicrobial susceptibility of uroculturome of humans in health and urinary tract infections

Background:The uroculturome indicates the profile of culturable microbes inhabiting the urinary tract,and it is often required to do a urine culture to find an effective antimicrobial to treat urinary tract infections(UTIs).Methods:This study targeted to understand the profile of culturable pathogens in the urine of apparently healthy(128)and humans with clinical UTIs(161)and their antimicrobial susceptibility.All the urine samples were analyzed to quantify microbial load and determine the diversity and antimicrobial susceptibility of microbes following standard microbiological methods.Results:In urine samples from UTI cases,microbial counts were 1.2×10^(4)±6.02×10^(3) colony-forming units(cfu)/mL,while in urine samples from apparently healthy humans,the average count was 3.33±1.34×10^(3) cfu/mL.In eight samples(six from UTI cases and two from apparently healthy people,Candida(C.albicans 3,C.catenulata 1,C.krusei 1,C.tropicalis 1,C.parapsiplosis 1,C.gulliermondii 1)and Rhizopus species(1)were detected.Candida krusei was detected only in a single urine sample from a healthy person and C.albicans was detected both in urine of healthy and clinical UTI cases.Gram-positive(G+ve)bacteria were more commonly(Odds ratio,1.98;CI99,1.01-3.87)detected in urine samples of apparently healthy humans,and Gram-negative(G−ve)bacteria(Odds ratio,2.74;CI99,1.44-5.23)in urines of UTI cases.From urine samples of 161 UTI cases,a total of 90 different types of microbes were detected and,73 samples had only a single type of bacteria.In contrast,49,29,3,4,1,and 2 samples had 2,3,4,5,6 and 7 types of bacteria,respectively.The most common bacteria detected in urine of UTI cases was Escherichia coli(52 samples),in 20 cases as the single type of bacteria,other 34 types of bacteria were detected in pure form in 53 cases.From 128 urine samples of apparently healthy people,88 types of microbes were detected either singly or in association with others,from 64 urine samples only a single type of bacteria was detected while 34,13,3,11,2 and 1 sample yielded 2,3,4,5,6 and seven types of microbes,respectively.In the urine of apparently healthy humans too,E.coli was the most common bacteria,(10 samples)followed by Staphylococcus haemolyticus(9),S.intermedius(5),and S.aureus(5),and similar types of bacteria also dominated in cases of mixed occurrence,E.coli was detected in 26,S.aureus in 22 and S.haemolyticus in 19 urine samples,respectively.G+ve bacteria isolated from urine samples’irrespective of health status were more often(P<0.01)resistant than G−ve bacteria to ajowan oil,holy basil oil,cinnamaldehyde,and cinnamon oil,but more susceptible to sandalwood oil(P<0.01).However,for antibiotics,G+ve were more often susceptible than G−ve bacteria to cephalosporins,doxycycline,and nitrofurantoin.Conclusion:The study concludes that to understand the role of good and bad bacteria in the urinary tract microbiome more targeted studies are needed to discern the isolates at the pathotype level.Further,the study suggests the use of antibiotics by observing good antibiotic stewardship following antibiotic susceptibility testing only.

Detection of Beta-Lactamase and Extended-Spectrum Beta-Lactamase of Pathogens Isolated from Pig and Chicken and Their Antibiotic Susceptibility Test

The antibacterial activity of beta-lactam antibiotics or their combinations with inhibitor sulbactum against non-lactamase- producing strains, lactamase-producing and ESBLs-producing isolates was evaluated with twofold dilution method after pathogens isolated from pigs and chickens were detected, respectively, for beta-lactamase and extended-spectrum beta- lactamases （ESBLs）, The results revealed that most of 43 clinically isolated strains could produce beta-lactamase and 3 strains of shigella isolated from chicken samples produced ESBLs. All of 30 lactamase-producing strains isolated and only one of 16 non-lactamase-producing strains were resistant to amoxicillin and ampicillin. MICs of ampicillin against lactamaseproducing isolates decreased 10-40 and 10-20 times respectively, when it was conbined with sulbactam at ration of 1：2 and 1：4. All clinical isolates were susceptible to third-generation cephalosporins. The MICs of third-generation cephalosporins against lactamase-producing isolates did not change when they were conbined with sulbactam. MICs of ceftiofur and ceftriaxone against ESBLs-producing isolates decreased 2-4 times when they were conbined with sulbactam.

Assessment of Clinical Presentation, Performance of Diagnostic Methods and Antibiotic Susceptibility Testing for Salmonella among Patients Attending Kangema Sub-County Hospital, Kenya

Background: Typhoid disease remains a major public health problem globally, especially in developing countries in sub-Saharan Africa. Symptoms associated with typhoid disease mimic those of other febrile illnesses and are thus difficult to make an accurate diagnosis. A confirmed diagnosis requires the determination or isolation of the bacteria in well-equipped laboratories. Developing countries are faced with a huge limitation of the laboratory infrastructure to diagnose typhoid disease, which would otherwise guide in treating, managing, controlling, and halting the spread of drug resistant mutants. Objective: This study, therefore, was aimed at determining the clinical presentation, performance of diagnostic tests and antibiotic susceptibility testing of Salmonella among adults attending Kangema Sub-County Hospital. Study Population: The study population was residents of Kangema Sub-County in Murang’a County, Kenya while the target population was adults. Methods: The study adopted a cross-sectional study design that employed a systematic random sampling procedure. The study took place between April and June 2021. The sample size was 97 respondents who all consented and were enrolled in the study. Interviewing the respondents was carried out by administering structured questionnaires to collect quantitative data. Stool samples were obtained and cultured in Cary Blair transport media and then cultured in appropriate media at the Murang’a County Referral Hospital Laboratory. A rapid Salmonella Antigen (SAT) test was also performed on all the stool samples. Data Analyses: Word Statistics and Data (STATA) v 13 was used for statistical analysis. Results: The prevalence of Typhoid Fever was at 6.2% (95% CI) which included S. Typhi (n = 1;16.7%) and S. Paratyphi B (n = 5;83.3%). No isolate showed resistance to Ciprofloxacin. The sensitivity of SAT is 100% and a specificity of 98.9% with a kappa statistic of almost perfect agreement (0.9641) with culture. Patients who had fever p = 0.001, abdominal distention p = 0.028, diarrhoea p = 0.038, loose or watery stool p = 0.021 and mild general condition p = 0.02 remained independently associated with Salmonella infection. Conclusion: Typhoid Fever being endemic, laboratory diagnosis was a key for confirmation after clinical diagnosis. SAT can accurately be used to detect the disease where culture is unavailable. However, antibiotic sensitivity tests were crucial when determining the drug of choice as Salmonella isolates were multi-drug resistant. Establishment of prescribing antimicrobial policies and guidelines can periodically monitor the antibiogram patterns.

A Retrospective Study on the Pyogenic Pathogens and Their Antibiotic Susceptibility Patterns along with the ES<i>β</i>L Production

Pyogenic infections are caused by various pathogens leading to pus formation and that can be attributed due to a wound either through accident or during surgery leading to infection spread. There are pathogenic strains that are not uncommon in hospital settings like Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter etc., that are multidrug resistant (MDR) and are a cause of concern. The bacteriological profile in the pyogenic infections tends to be same but there is a vast difference with the antibiotic resistant patterns in different hospital settings. Hence, the aim was to study the antibiotic susceptibility profiles and Extended spectrum βeta Lactamases (ESβL) production in these pathogens. A prospective study was carried out in Silchar Medical College and Hospital Assam, India, over a four-month period from February to May 2021. The samples were processed using Blood and MacConkey’s agar. Further, these isolated pathogens were identified by standard morphological, cultural and biochemical tests. The antibiotic susceptibility test was conducted by Kirby Bauer disc diffusion method and ESβL production was detected by using combined disk diffusion test. It was observed that the identified pathogens had an incidence rate of 84.2% and further revealed that Gram negative had a higher incidence rate compared to Gram positive with 59.8%. The pathogens isolated from pus samples had a maximum of Klebsiella sps (19.64%) and the lowest was E. coli with 5.36%. Antibiotic susceptibility test (AST) of Gram-negative bacterial isolates showed the highest incidence with aztreonam (40.6%) and the lowest was observed in Piperacillin/Tazobactam with 7.5%. The only Gram positive was observed in our study, Staphylococcus aureus had the highest resistance in amikacin with 80% and interestingly, all the isolates were sensitive to Linezolid with 100%. There is a high rise and spreading with the multi-drug resistance (MDR) strains along with ESβL production and it was observed in our studies that these pathogens had an incidence rate of 18.5%. The highest was 58.1% in Pseudomonas sps. None of Proteus sps were found to be ESβL producers. To combat resistance, the irrational use of antibiotics should be avoided and surveillance of the rising multidrug species regularly helps in implementing better therapeutic options to reduce the morbidity and mortality.

Culture-guided treatment approach for Helicobacter pylori infection:Review of the literature

The progressive loss of efficacy of standard eradication therapies has made the treatment of Helicobacter pylori (H. pylori) more challenging than ever. Endoscopic-guided antibiotic susceptibility testing had previously been suggested to guide treatment after failure of second-line therapies. However, its role has expanded over the years, in accordance with the current Maastricht Guidelines. Several authors have dealt with this topic, developing both efficacy trials and cost-effectiveness trials against resistant H. pylori infections as well as infections in na&#x000ef;ve patients. However, results are not homogeneous enough to provide definite advice, because antibiotic resistance is not the only reason for treatment failure. Moreover, the culture-guided approach is surrounded by many practical issues, such as the availability of both endoscopy units and microbiology laboratories, and the need for a standard of quality that cannot be satisfied everywhere. Finally, pre-treatment susceptibility testing should be part - and not the only weapon - of a targeted, personalized strategy to overcome H. pylori infection.

General Evaluation of Biocide （Bt-ASF-1） Produced from Iraqi Isolate of Bacillus thuringiensis

General evaluation of isolate Bacillus thuringiensis （Bt-ASF-1） used as biocide in meddle scale application was conducted. Some morphological and confirmation tests were achieved. The sensitivity tests had been accomplished by diffusion and dilution techniques to determine the response of isolate against the antibiotics. The results of diffusion tests showed to the sensitivity of bacteria to antibiotics of cefixime, erythromycin, gentamicin and tetracycline respectively. It was resistant to trimethoprim sulfonamide （TMP）, bacitracin, penicillin and all its generations, and moderate resistance to nalidixic acid. Minimum Inhibitory Concentration （MIC） for amoxicillin was ranged between 30-40 pg/mL and these results are an approximation of the universal findings. Curing experiments showed the effective role of sodium dodecyl sulfate （SDS） （1.5%） comparing with temperature. The bacterial cells became sensitive to amoxicillin and TMP. The curing by temperature did not differ significantly from control treatment in plasmid pattern or antibiotics response. Plasmid profile referring that curing by SDS has been caused disturbance in beta -lactamase genes through the sensitivity to amoxicillin and remaining resistance to ampicillin. Curing isolate by SDS also became more sensitive to nalidixic acid, erythromycin and tetracycline respectively. It was found from the curing treatments the complexity distribution of r-genes between different plasmid size and chromosome but not effect on their insecticidal ability.

Recent advances in droplet microfluidics for microbiology

Advances in microbiology rely on innovations in technology. Droplet microfluidics, as a versatile and powerful technique that allows high-throughput generation and manipulation of subnanoliter volume droplets, has become an indispensable tool shifting experimental paradigms in microbiology. Droplet microfluidics has opened new avenues to various microbiological research, from resolving single-cell heterogeneity to investigating spatiotemporal dynamics of microbial communities, from precise quantitation of microbiota to systematic decipherment of microbial interactions, and from isolating rare and uncultured microbes to improving genetic engineered strains. In this review, we present recent advances of droplet microfluidics in various fields of microbiology: i) microbial cultivation, ii) microorganism detection and characterization, iii) antibiotic susceptibility testing, iv) microbial interactions, v) microbial biotechnology.We also provide our perspectives on the challenges and future directions for droplet microfluidic-based microbiology research.

Detection of Legionella pneumophila from domestic water and their antibiotic resistance profiles

Objective:To investigate the presence of Legionella pneumophila(L.pneumophila)in domestic water in Bitlis province and to determine the in vitro susceptibility of the isolates against several antibiotics.Methods:A total of 320 tap water samples were collected from the urban areas and villages of Bitlis province during the period from May to December 2010.All samples were cultured on plates of buffered charcoal yeast extract agar.L.pneumophila strains were tested for antimicrobial susceptibility by the disk diffusion method.Results:L.pneumophila strains were isolated from six(1.9%)domestic water samples.All isolates were typed as L.pneumophila serogroup 1 by latex agglutination test.Four of strains were isolated in July and two of them were detected in August.Antibiotic susceptibility testing was carried out on six L.pneumophila serogroup 1 isolates.Of the six strains,two was resistant to erythromycin and streptomycin,four were resistant to ampicillin and gentamicin,but all were sensitive to chloramphenicol and doxycycline.Conclusions:Our results indicate that L.pneumophila serogroup 1 is the most common type in the domestic water samples and threats public health.This is the first report of L.pneumophila in domestic water samples from Bitlis province.