Identification Of Pathogenic Bacteria Research Articles

Bacteriological testing and recurrence prevention efforts in the diagnosis and treatment of nursing- and healthcare-associated pneumonia and aspiration pneumonia: A questionnaire survey of hospitals across Japan.

Clinical practice guidelines for nursing- and healthcare-associated pneumonia (NHCAP) were developed for pneumonia caused by drug-resistant bacteria and pneumonia in elderly patients, particularly aspiration pneumonia. The identification of pathogenic bacteria and implementation of efforts to prevent the recurrence of aspiration pneumonia are very important in clinical practice. This study examined the extent to which clinicians have established bacteriological testing and recurrence prevention efforts for NHCAP and aspiration pneumonia. Questionnaire surveys were mailed to the heads of internal medicine and respiratory medicine departments at 2490 Japanese hospitals. The questionnaire evaluated bacteriological testing for NHCAP or aspiration pneumonia and prevention of the recurrence of aspiration pneumonia. A total of 350 hospitals responded. These hospitals were grouped on the basis of whether a pulmonologist provided medical care for aspiration pneumonia and whether the hospital employed an infectious disease specialist. For hospitals in which pulmonologists treated aspiration pneumonia, the response rates for "is done in nearly all cases" were 70.0%, 84.7%, 31.6%, and 48.9% for sputum gram staining, sputum culture tests, blood culture tests, and pneumococcal vaccination, respectively. In hospitals that employed an infectious disease specialist, the response rates for "is done in nearly all cases" were 72.8% and 41.3% for sputum gram staining and blood culture tests, respectively. Recurrence prevention for aspiration pneumonia (other than pneumococcal vaccination) was not actively implemented. Sputum gram staining, sputum culture tests, and other bacteriological tests were implemented quite actively. However, physicians who treat aspiration pneumonia should implement efforts to prevent pneumonia recurrence more actively.

Isolation and Identification of Pathogenic Bacteria from Urinary Tract Infections in Infants from Different Hospitals of District Peshawar

In the present study isolation and identification of pathogenic bacteria, causing urinary tract infection in infants was performed. The research work was carried out at the Microbiology Laboratory, Abasyn University, Peshawar. Samples were collected from different hospitals of District Peshawar. The collected samples were inoculated on different media for identification and isolation such as Nutrient agar, MacConkey agar, Mannitol salt agar and CLED media. For further identification Gram staining and Biochemical tests were performed such as Catalase, Oxidase, Coagulase, Indole and TSI. In total of 90 samples, E. coli was most prominent, which was found to be 52 (57.77%) followed by S. saprophyticus 22 (24.44%), K. pneumonia 11 (12.22%).While least prominent was S. aureus 5 (5.55%). Among the total isolates the percentage of Gram-negative bacteria in UTI patients was higher than Gram-positive bacteria. Whereas the percentage of E. coli was (53%) and K. pneumonia was (14%) while the percentage of S. saprophyticus was (28%) and S. aureus (5%). Among the total 90 isolates, the highest prevalence was observed in female infants about (58.88%) while in male infants, the percentage was (41.11%). Key words: Urinary Tract Infection, Infants, Pathogenic Bacteria.

Identification of pathogenic bacteria in complex samples using a smartphone based fluorescence microscope.

Diagnostics based on fluorescence imaging of biomolecules is typically performed in well-equipped laboratories and is in general not suitable for remote and resource limited settings. Here we demonstrate the development of a compact, lightweight and cost-effective smartphone-based fluorescence microscope, capable of detecting signals from fluorescently labeled bacteria. By optimizing a peptide nucleic acid (PNA) based fluorescence in situ hybridization (FISH) assay, we demonstrate the use of the smartphone-based microscope for rapid identification of pathogenic bacteria. We evaluated the use of both a general nucleic acid stain as well as species-specific PNA probes and demonstrated that the mobile platform can detect bacteria with a sensitivity comparable to that of a conventional fluorescence microscope. The PNA-based FISH assay, in combination with the smartphone-based fluorescence microscope, allowed us to qualitatively analyze pathogenic bacteria in contaminated powdered infant formula (PIF) at initial concentrations prior to cultivation as low as 10 CFU per 30 g of PIF. Importantly, the detection can be done directly on the smartphone screen, without the need for additional image analysis. The assay should be straightforward to adapt for bacterial identification also in clinical samples. The cost-effectiveness, field-portability and simplicity of this platform will create various opportunities for its use in resource limited settings and point-of-care offices, opening up a myriad of additional applications based on other fluorescence-based diagnostic assays.

Diversity analysis of acute hepatopancreatic necrosis disease-positive Vibrio parahaemolyticus strains

Acute hepatopancreatic necrosis disease (AHPND), also called early mortality syndrome (EMS), has caused massive economic loss in aquaculture since 2009. It was considered that the disease was caused by a novel type of Vibrio parahaemolyticus which harbors a large plasmid. Two insecticidal Photorhabdus insect-related (pir) genes were found in the plasmid. In this study, 81 isolates have been collected from a shrimp farm in Maoming, Guangdong Province, PRC. Suspected isolates were identified using 3 pairs of primer recently made public. Both the 16S rRNA gene and pir gene were sequenced. ERIC-PCR was employed for analysis of strain diversity. 12 isolates were amplified by PCR and identified as Vibrio parahaemolyticus by 16S rRNA sequence alignment. Sequence alignments of the pir gene showed few mutations in the 12 strains of V. parahaemolyticus. The 12 strains separated into 3 clusters at a cut of 90% similarity by ERIC-PCR. The virulence gene expression and toxicity profile showed differences between strains. This study generated comprehensive identification of pathogenic bacteria and microbial molecular resources, which will contribute to future research of AHPND.

Electrospun boronic acid-containing polymer membranes as fluorescent sensors for bacteria detection

In this work, a boronic acid copolymer, poly(4-vinylphenylboronic acid-co-2-(dimethylamino)ethyl methacrylate-co-n-butyl methacrylate) (pVDB) was designed for the rapid detection of bacteria based on reversible boronate ester formation with the diol-rich saccharide moieties found on bacterial membranes. Electrospun nanofibre membranes were prepared from a blend of polyacrylonitrile (PAN) and pVDB, which was synthesized by free radical polymerization. The pVDB@PAN membranes were used as fluorescent bacterial biosensors, displaying a distinct emission at 538nm when in contact with bacteria cells. The fluorescence intensity showed a maximum intensity after 24h of contact with Staphyloccocus aureus or Escherichia coli, and this intensity increased proportionally with the pVDB content in the electrospun membranes. When in contact with Pseudomona putida, the membranes became non-responsive within 8h due to the rapid formation of a bacterial biofilm. This fouling phenomena blocked the membrane surface for fluorescence readings. The pVDB@PAN bionsensor allowed for the rapid detection of the early stages of bacterial colonization well before biofilm formation, which could be advantageous for the early identification of pathogenic bacteria and prevention of their spreading.

Identification of Pathogenic Bacteria Isolated from Raw and After Sand Filtration Water at Lubok Buntar Water Treatment Plant

This study focused on the identification of pathogenic bacteria in raw water intake and after sand filtration for drinking water treatment plant during flood event in 2014. The samples was collected from the Lubok BuntarWater Treatment Plant (WTP) and processed through bacterial isolation using chocolate agar as a media. The isolation process conducted based on serial samples dilution and streaking method prior to DNA extraction.Deoxyribonucleic acid (DNA) extraction kit was used to get selected bacteria DNA and further analysis using Polymerase Chain Reaction (PCR) test and electrophoresis to get DNA sequences. The Basic Local Alignment Search Tool (BLAST) analysis was employed to identify the species of the isolated bacteria. As a result, Pantoeaagglomerans and Enterobacter sp. were found in raw and filtered water sample and indicating the same family types. It was concluded that bacteria of the same species were found before and after sand filtration and need to be removed by disinfectant process. The findings also indicated that all the physicochemical parameters measured were within the values prescribed by the Interim National Water QualityStandard (INWQS).

Meningoencephalitis in farmed monosex Nile tilapia (Oreochromis niloticus L.) caused by Streptococcus agalactiae

Abstract Aquaculture of tilapia is a new research venture in India. With intensification in farming practices, tilapia are increasingly susceptible to bacterial infections. This article describes the isolation and identification of pathogenic bacteria from cultured monosex Nile tilapia, Oreochromis niloticus (L.), that experienced moderate to severe mortalities in West Bengal, India between September and August 2014 and histopathological alterations in various organs. Gram-positive diplococci, identified as Streptococcus agalactiae with Streptococcus identification kits and 16S rDNA sequencing analysis, were isolated from the brain, operculum, and kidney. Other bacteria from the kidney were identified as Aeromonas sobria, A. caviae, Klebsiella pneumoniae ssp. pneumoniae, Escherichia coli, and Enterobacter cloacae. Staphylococcus epidermis was isolated from opercular hemorrhages. Histological sections of the infected tilapia brain revealed meningoencephalitis and granulomatous lesions. Sections from other organs indicated congestion, hemorrhagic and hyperplastic cells, necrosis, vacuolation, hemosiderin deposition, hypertrophic nuclei, melanomacrophage aggregation, and ruptured veins. This report is the first description of S. agalactiae as a primary pathogen causing meningoencephalitis in cultured tilapia in India.

PathoBacTyper: A Web Server for Pathogenic Bacteria Identification and Molecular Genotyping.

With the decline in the cost of whole-genome sequencing because of the introduction of next-generation sequencing (NGS) techniques, many public health and clinical laboratories have started to use bacterial whole genomes for epidemiological surveillance and clinical investigation. For epidemiological and clinical purposes in this “NGS era,” whole-genome-scale single nucleotide polymorphism (wgSNP) analysis for genotyping is considered suitable. In this paper, we present an online service, PathoBacTyper (http://halst.nhri.org.tw/PathoBacTyper/), for pathogenic bacteria identification and genotyping based on wgSNP analysis. More than 400 pathogenic bacteria can be identified and genotyped through this service. Four data sets containing 59 Salmonella Heidelberg isolates from three outbreaks with the same pulsed-field gel electrophoresis pattern, 34 Salmonella Typhimurium isolates from six outbreaks, 103 isolates of hospital-associated vancomycin-resistant Enterococcus faecium and 15 Legionella pneumophila isolates from clinical and environmental samples in Israel were used for demonstrating the operation and testing the performance of the PathoBacTyper service. The test results reveal the applicability of this service for epidemiological typing and clinical investigation.

A DNA biosensor for molecular diagnosis of <i>Aeromonas hydrophila</i> using zinc sulfide nanospheres

Abstract. Today, identification of pathogenic bacteria using modern and accurate methods is inevitable. Integration in electrochemical measurements with nanotechnology has led to the design of efficient and sensitive DNA biosensors against bacterial agents. Here, efforts were made to detect Aeromonas hydrophila using aptamers as probes and zinc sulfide (ZnS) nanospheres as signal enhancers and electron transfer facilitators. After modification of the working electrode area (in a screen-printed electrode) with ZnS nanospheres through electrodeposition, the coated surface of a modified electrode with ZnS nanospheres was investigated through scanning electron microscopy (SEM). The size of synthesized ZnS nanospheres was estimated at about 20–50 nm and their shape was in the form of porous plates in microscopic observations. All electrochemical measurements were performed using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and constant potential amperometry (CPA) techniques. The designed DNA biosensor was able to detect deoxyribonucleic acid (DNA) of Aeromonas hydrophila in the range 1.0 × 10−4 to 1.0 × 10−9 mol L−1; the limit of detection (LOD) in this study was 1 × 10−13 mol L−1. This DNA biosensor showed satisfactory thermal and pH stability. Reproducibility for this DNA biosensor was measured and the relative standard deviation (RSD) of the performance of this DNA biosensor was calculated as 5 % during 42 days.

Identification of Pathogenic Bacteria Isolated from Raw and After Sand Filtration Water at Lubok Buntar Water Treatment Plant

This study focused on the identification of pathogenic bacteria in raw water intake and after sand filtration for drinking water treatment plant during flood event in 2014. The samples was collected from the Lubok Buntar Water Treatment Plant (WTP) and processed through bacterial isolation using chocolate agar as a media. The isolation process conducted based on serial samples dilution and streaking method prior to DNA extraction. Deoxyribonucleic acid (DNA) extraction kit was used to get selected bacteria DNA and further analysis using Polymerase Chain Reaction (PCR) test and electrophoresis to get DNA sequences. The Basic Local Alignment Search Tool (BLAST) analysis was employed to identify the species of the isolated bacteria. As a result, Pantoeaagglomerans and Enterobacter sp. were found in raw and filtered water sample and indicating the same family types. It was concluded that bacteria of the same species were found before and after sand filtration and need to be removed by disinfectant process. The findings also indicated that all the physicochemical parameters measured were within the values prescribed by the Interim National Water Quality Standard (INWQS).

The presence of atopy and its effect on bacterial colonization of the upper airways in children with adenoid vegetation

Background: The aim of this study was to determine the frequency of atopy and the influence of atopy on bacterial colonization of upper airway in children with adenoid hypertrophy. Material and methods: Forty children were enrolled in the prospective study. Presence of atopy was diagnosed by skin-prick test. Differences in bacterial colonization of middle nasal meatus and nasopharynx according to the presence of atopy were analyzed. Results: Atopy was diagnosed in 75% children with adenoid hypertrophy. Presence of atopy was associated with significantly more often colonization of pathogenic bacteria (Streptococcus pneumoniae, Hemophillus influaenzae, Moraxella catarrhalis, Staphylococcus aureus) in the middle nasal meatus but not in nasopharynx (P=0.045, P=0.483, respectively). Identification of pathogenic bacteria in middle nasal meatus did not correlate with isolation of pathogenic bacteria in nasopharynx in both groups of children. Conclusion: There is a high incidence of atopy in children with adenoid hypertrophy. Atopy is related to increased colonization by pathogenic bacteria in middle nasal meatus but not in nasopharynx.

The Antibacterial of Essential Fatty Acid Semicarbazide Extracted from Flaxseed Oil Against Some Nosocomial Infection Bacteria in Iraq

During the period from December 2014 to July 2015, isolation and identification of pathogenic bacteria from clinical sources attending to AL-Hakeem Hospital and AL-Sadder Medical City in AL-Najaf province. A total of One hundred clinical samples from various sources included: UTI - patients, Burn, postoperative surgery site –Wound, The results revealed the occurrence (52) bacterial isolate were isolated, 37(71%) were gram– positive bacteria that was divided into S. aureus 20(39%), S. pyogen 9 (17%), and S. pneumonia 8 (15%). But only 15 (29%) was gram – negative bacteria which represented by E. coli 7(13%), and P.aeruginasa 4 (8%), Protuse mirabilis 4(8%). The susceptibility of S. aureus and E.coli bacteria which are consider the most common G+ve and G-ve nosocomial pathogen to routenly used antibiotic in Najaf hospitals were tested by using antibiotic susceptibility pattrons, in order to select one isolate from S.aureus and other one from E.coli which had the higher resistance to most antibiotic for continue the other steps of these study. The result illustrated that S.aureus No.5 and E. coli No.3 were greatly resistant to antibiotics, so regard as multi-drug resistant(MDR). Crud extracts of Linum usitatissimum which had been extracted by three solvents (petroleum ether, hexan and aqueous), for studying the chemical contents of these extracts by using suitable reagents and tested antibacterial activity on the growth of studied S.aureus and E. coli bacteria. The extraction of Essential fatty acid Semicarbazide (omega-3-6- fatty acid) from Linum usitatissium (Flax seed) and the chemical and physical properties of isolated oil compounds were studied by using thin layer chromatography (TLC), ultraviolet spectrum (UV) and FTIR spectrum. The result revealed that shown high antibacterial activity against studied (S.aureus, E.coli). results explained broad spectrum antibacterial property of oil compounds against studied bacteria nosocomial.

Methods for the detection and identification of pathogenic bacteria: past, present, and future.

In order to retard the rate of development of antibacterial resistance, the causative agent must be identified as rapidly as possible, so that directed patient treatment and/or contact precautions can be initiated. This review highlights the challenges associated with the detection and identification of pathogenic bacteria, by providing an introduction to the techniques currently used, as well as newer techniques that are in development. Focusing on the chemical basis for these techniques, the review also provides a comparison of their advantages and disadvantages.

MICROBIAL BIODIVERSITY AND ANTIBIOTICS IN PERIODONTAL DISEASES A LITERATURE REVIEW

The Oral cavity is a reservoir of bacteria with high biodiversity, however, not all species can cause invasive diseases. Identification of pathogenic bacteria in the oral lesions is challenging because cultivation of specimens from this non sterile site invariably yields a diversity of bacteria, making associations between cultivated bacteria and particular oral lesions difficult. Periodontitis is a multifactorial disease which might have a systemic or hereditary component in addition to its bacterial aetiology. It is highly prevalent worldwide, affects 30-50% of the population in developed countries, but only ~10% present with severe forms. The microbial aetiology of periodontal disease has been proved since long time ago, approximately 500 species or more have been detected in the gingival sulcus, some of them are widely regarded as major pathogens in periodontitis. Periodontal microbiota are more heterogeneous than earlier believed, in dentistry, gram-negative organisms were considered to be the predominant bacteria in periodontitis; however, gram-positive organisms found in deep, diseased sites are proposed to be the most important pathogens in periodontitis recently. Using antibiotics in controlling periodontal diseases is essential, which either suppress the growth of microorganism or destroy them. Drugs used to treat periodontal disease can be used systemically or locally, however, some periodontopathic bacteria can develop resistance to certain antimicrobials specially in refractory periodontitis and aggressive periodontitis cases.

Species and drug resistance of pathogens causing bloodstream infections in hospitalized patients

Objective To investigate the distribution and resistance of positive pathogens isolated from blood culture and guide the use of antibiotics for clinical treatment and prevention treatment of bacteremia. Methods Collected the blood samples from 2014 to 2015 and cultivate by Bact ALERT 3D, pathogenic bacteria identification and antimicrobial susceptibility testing was carried out by VITEK 2 compact.The bacterial data were analyzed by WHONET 5.6 software, according to the breakpoints of CLSI 2014. Results Among the 16 751 blood culture samples, 893 cases showed positive and the positive rate was 5.3%.Among the strains, the percentage of the gram-positive bacteria was 423, including coagulase-negative Staphylococcus(62.9%), S.aureus(8.6%), Enterococcus(13.8%); the percentage of the gram-negative bacteria was 419, including Escherichia coli(47.0%), Klebsiella pneumonia(16.5%), Pseudomonas aeruginosa(4.9%), Stenotrophomonas maltophilia(4.5%) and Brukhoderial.cepacia(3.8%); the percentage of fungi was 5.7%, including Candida albicans(76.5%) and candida parapsilosis(23.5%). The prevalence of ESBLs producing strains was 56.0% in E. coli and K. pneumoniae.The average prevalence of methicillin-resistant strains in S. aureus(MRSA) and coagulase-negative Staphylococcus(MRCNS) was 25.0% and 67.8% respectively.Enterobacteriaceae strains were still highly susceptible to the carbapenem drug.The rate of CRE was zero.The resistance to vancomycin, linezolid and quinupristin/Dafoe leptin was not found in Staphylococcus.VRE was not found. Conclusion There was a variety of pathogens leading to bloodstream infection which show a relative sensitive resistance to many antimicrobial agents.Meanwhile, the multi-drug resistant strains may have serious consequences, and the monitoring and rational use of antibiotics should be strengthened. Key words: Bacterial infections; Drug resistance, bacteria

Acoustofluidic bacteria separation

Bacterial separation from human blood samples can help with the identification of pathogenic bacteria for sepsis diagnosis. In this work, we report an acoustofluidic device for label-free bacterial separation from human blood samples. In particular, we exploit the acoustic radiation force generated from a tilted-angle standing surface acoustic wave (taSSAW) field to separate Escherichia coli from human blood cells based on their size difference. Flow cytometry analysis of the E. coli separated from red blood cells shows a purity of more than 96%. Moreover, the label-free electrochemical detection of the separated E. coli displays reduced non-specific signals due to the removal of blood cells. Our acoustofluidic bacterial separation platform has advantages such as label-free separation, high biocompatibility, flexibility, low cost, miniaturization, automation, and ease of in-line integration. The platform can be incorporated with an on-chip sensor to realize a point-of-care sepsis diagnostic device.

Assessment of carbon nanotubes and silver nanoparticles loaded clays as adsorbents for removal of bacterial contaminants from water sources.

This work evaluated the antimicrobial efficacy of kaolin clay and its loaded forms with carbon nanotubes (CNTs) and silver nanoparticles (AgNPs) against bacterial isolates from different water supplies (tap, underground and surface water) in addition to wastewater. A total of 160 water samples were collected from different water sources in the investigated districts. Samples were cultured for isolation and serological identification of pathogenic bacteria. AgNPs were synthesized by a typical one-step synthesis protocol, where CNTs were carried out in a reactor employing the double bias-assisted hot filament chemical vapor deposition method. Both were characterized using transmission electron microscopy, infrared and X-ray fluorescence (XRF) spectroscopy. The antimicrobial efficacy of each of natural kaolin clay, AgNPs- and CNTs-loaded clays were evaluated by their application in four concentrations (0.01, 0.03, 0.05 and 0.1 ppm) at different contact times (5 min, 15 min, 30 min and 2 h). AgNPs-loaded clays at concentrations of 0.05 and 0.1 mg/l for 2 h contact time exhibited a higher bactericidal efficacy on Escherichia coli and Salmonella spp. (70, 70, 80 and 90%, respectively) compared to CNTs-loaded clay. Concluding, the application of AgNPs-loaded clay for removal of water bacterial contaminants at a concentration of 0.1 ppm for 2 h contact times resulted in highly effective removals.

BAKTERI AEROB PATOGEN DAN UJI KEPEKAAN ANTIMIKROBA DI RUANGAN PERAWATAN PENYAKIT DALAM

Pathogenic bacteria are the major causes of airborne infection at the hospital ward. Nosocomial infection can occur at the opened as well as at the closed room. Nosocomial infection influences the morbidity and mortality in the hospital and need an extra attention, because of the increased number of hospital patients, micro organism mutation and increased of bacteria resistance to antibiotics. The aim of this study was to quantify the number of aerobic bacteria, and to know the pathogenic bacteria identification and its determination on the susceptibility of the antimicrobial problems at the internal medicine ward. This research was carried by a cross sectional study, which performed by collecting air samples in eight internal medicine ward of Dr. Wahidin Sudirohusodo Hospital using Microbiology Air Sampler 100 (MAS 100). The bacterial identification and the antimicrobial susceptibility test (AST) were conducted at the Balai Besar Laboratorium Kesehatan (July to August 2009). In this study were found the numbers of bacteria colonies about 580–6040 CFU/m3. The pathogenic bacteria that identified were Acinetobacter calcoaceticus, Staphylococcus saprohpyticus, Enterobacter hafniae and Stomatococcus mucilaginosus that were sensitive to Amikasin, Gentamicyn, Azitromycin and Norfloxacyn but resistant to Ampicillin. The number of bacterial colonies exceeded the established number standard by Decree of the Indonesian Health Minister. The pathogenic bacteria showed the most sensitive result of AST were Acinetobacter calcoaceticus, Enterobacter hafniae, Stomatococcus mucilaginosus and Staphylococcus saprohpyticus.

Performance evaluation of three automated identification systems in detecting carbapenem-resistant Enterobacteriaceae.

BackgroundCarbapenem-resistant Enterobacteriaceae (CRE) is prevalent around the world. Rapid and accurate detection of CRE is urgently needed to provide effective treatment. Automated identification systems have been widely used in clinical microbiology laboratories for rapid and high-efficient identification of pathogenic bacteria. However, critical evaluation and comparison are needed to determine the specificity and accuracy of different systems. The aim of this study was to evaluate the performance of three commonly used automated identification systems on the detection of CRE.MethodsA total of 81 non-repetitive clinical CRE isolates were collected from August 2011 to August 2012 in a Chinese university hospital, and all the isolates were confirmed to be resistant to carbapenems by the agar dilution method. The potential presence of carbapenemase genotypes of the 81 isolates was detected by PCR and sequencing. Using 81 clinical CRE isolates, we evaluated and compared the performance of three automated identification systems, MicroScan WalkAway 96 Plus, Phoenix 100, and Vitek 2 Compact, which are commonly used in China. To identify CRE, the comparator methodology was agar dilution method, while the PCR and sequencing was the comparator one to identify CPE.ResultsPCR and sequencing analysis showed that 48 of the 81 CRE isolates carried carbapenemase genes, including 23 (28.4 %) IMP-4, 14 (17.3 %) IMP-8, 5 (6.2 %) NDM-1, and 8 (9.9 %) KPC-2. Notably, one Klebsiella pneumoniae isolate produced both IMP-4 and NDM-1. One Klebsiellaoxytoca isolate produced both KPC-2 and IMP-8. Of the 81 clinical CRE isolates, 56 (69.1 %), 33 (40.7 %) and 77 (95.1 %) were identified as CRE by MicroScan WalkAway 96 Plus, Phoenix 100, and Vitek 2 Compact, respectively. The sensitivities/specificities of MicroScan WalkAway, Phoenix 100 and Vitek 2 were 93.8/42.4 %, 54.2/66.7 %, and 75.0/36.4 %, respectively.ConclusionsThe MicroScan WalkAway and Viteck2 systems are more reliable in clinical identification of CRE, whereas additional tests are required for the Pheonix 100 system. Our study provides a useful guideline for using automated identification systems for CRE identification.

Identification of Pathogenic Bacteria in Blood Cultures and Susceptibility Testing of Isolates With Various Antibiotics

Background: Blood infections are an extensive range of disorders that can vary from limited bacteremia to fatal septicemia. Bac- teremia refers to the transient presence of a bacterium in the bloodstream. A delay in the diagnosis and treatment of sepsis can cause mortality, with a 20% - 50% prevalence rate. Objectives: Due to the changing patterns of antibiotic resistance, as well as dierences in patterns over time in dierent settings, we decided to identify infectious agents and their antibiotic resistance patterns in blood cultures. Materials and Methods: This study was conducted at Shahid Beheshti hospital, Hamadan, Iran, during a one-year period (March 21, 2014, to March 22, 2015). From patients with suspected bloodstream infections, 5-10 mL of blood was collected three times and inoculated into culture bottles. After identifying the types of microorganisms, susceptibility testing was performed according to CLSI standards, and the results were analyzed with statistical software. Results: In the present study, 2,130 blood cultures were obtained from 710 patients (384 females and 326 males). Of these cultures, 232 (18.9%) were positive; 107 (46%) and 125 (54%) were from females and males, respectively. Most of the positive cultures were re- lated to the internal medicine and hematology wards, which had 132 cases (56.9%), and the ICU, with 37 cases (16%). The most frequent isolates were Pseudomonas aeruginosa, Escherichia coli, Acinetobacter baumannii, and coagulase-negative Staphylococcus aureus, with prevalence rates of 18.2%, 24.1%, 10.3%, and 10.3%, respectively. The most eective antibiotic against Gram-positive isolates was van- comycin. Conclusions: This study revealed that the most eective antibiotics against two Gram-negative and Gram-positive groups were amikacin and norfloxacin, so it is recommended that these antibiotics be used empirically, at least in the setting where this study was conducted, before performing the culturing and antibiogram process.