Identification Of Causative Agent Research Articles

P411 Genus specific real-time PCR-a promising technique for rapid diagnosis of fungal keratitis

Poster session 3, September 23, 2022, 12:30 PM - 1:30 PMObjectiveComparison of different existing molecular methods for diagnosis of fungal keratitis (FK) and to develop and validate genus-specific PCR for identification of most predominant FK causative agents.MethodA prospective multicentric study was performed between November 2019 to August 2021 from four centers across India. Corneal tissue/scraping samples were collected from patients with suspected keratitis for preliminary microbiological workup at respective centers and molecular diagnosis at the Postgraduate Institute of Medical Education and Research (PGIMER), Chandigarh. A total of 87 corneal button samples were used for standardization. All samples were subjected to DNA extraction followed by molecular diagnosis using pan-fungal primers by conventional PCR, semi-nested PCR, and real-time PCR targeting the internal transcribed spacer (ITS) region of rDNA. The genus-specific primers for the most common causative agents of FK (Aspergillus sp., Fusarium sp., Alternaria sp., and Curvularia sp.) were designed in ITS2 region and standardized for real-time PCR. The best performing protocol was validated in 145 corneal samples.ResultA total of 68 patients out of 87 were diagnosed with FK of which 91.17% (n = 62/68) were microscopy positive and 82.3% (n = 56/68) were culture positive. Among the culture positive, the most common isolate was Aspergillus sp. (26, 46.42%) followed by Fusarium sp. (21, 37.5%) while the remaining samples grew dematiaceous fungi. Real-time PCR targeting ITS2 region proved to be most sensitive (52.94%) and specific (84.21%) compared with conventional PCR and semi-nested PCR. Genus-specific real-time PCR for Aspergillus sp. and Fusarium sp. showed improved sensitivity and specificity of 82.76%, 87.18%, and 90.91%, 93.48% respectively compared with all other diagnostic methods used in the study. The positive (PPV) and negative predictive value (NPV) for Aspergillus sp. specific PCR were 82.76% and 87.18% while Fusarium sp. specific PCR showed PPV of 86.96% and NPV of 95.56%. Genus-specific real-time PCRs did not show any amplification of 19 FK negative samples while faint amplification was observed in conventional PCR which on sequencing proved to be non-specific. No cross-reactivity was observed in clinical sample standardization. Due to the lack of Alternaria sp. and Curvularia sp. positive clinical samples, both PCRs were standardized using respective culture DNA which showed a positive result. Aspergillus sp. and Fusarium sp. genus-specific PCRs were further validated in 145 corneal samples, of which 91 were FK positive and showed similar results as that of standardization data. Genus-specific PCRs also reduced the turnaround time (˂24 h) by decreasing the need for the identification of causative agents.ConclusionReal-time PCR targeting ITS 2-region, particularly the genus-specific PCRs proved to be the most efficient for molecular diagnosis of FK. The genus-specific PCRs reduce the turnaround time by avoiding the need for sequencing and thus facilitating in rapid diagnosis of FK.

P148 Emerging and cryptic Aspergillus species isolated from hospitalized patients with underlying primary immunodeficiencies

Poster session 2 September 22 2022 12:30 PM - 1:30 PM ObjectivesAlthough Aspergillus fumigatus is the most common etiologic agent of invasive aspergillosis multiple poorly recognized non-fumigatus species have been reported from patients with iatrogenic immunosuppression and individuals with underlying primary immunodeficiencies (PIDs). The species-level identification of causative agents and the determination of antifungal susceptibility patterns can play significant roles in the outcome of aspergillosis. In the current study we aimed to investigate the frequency of non-fumigatus Aspergillus species isolated from hospitalized patients with PIDs at National Institutes of Health (NIH) Clinical Center Bethesda MD USA.MethodsIn a prospective study between January 2019 and December 2021 a total of 279 Aspergillus species were isolated from NIH hospitalized patients with underlying PIDs. The species-level identification of each isolate was attempted by colony morphology microscopic characteristics matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF) and PCR-sequencing of the internal transcribed spacer (ITS) region of ribosomal DNA the β-tubulin and Calmodulin (CaM) genes.ResultsOverall members of Aspergillus section Fumigati were the most common group (71%) followed by section Veriscolores (7%) section Usti (4%) section Tanneri (4%) section Terrei (3%) section Nigri (3%) and section Nidulantes (3%). Aspergillus species belong to sections Falvi Clavati Flavipedes and Circumdati were less frequent and each counted for only 1% of the total isolates identified.Notably cryptic and non-fumigatus members of section Fumigati comprised only 12% of the isolates including A. felis A. udagawae A. lentulus A. thermomutatus A. viridinutans, and A. pseudoviridinutans while A. fumigatus was the dominant species (88%).MALDI-TOF assay was able to properly differentiate sections of Aspergillus from each other. However PCR-sequencing of the β-tubulin gene was the most reliable target to separate the cryptic species of each section.ConclusionOur study shows that frequency of rare and cryptic Aspergillus species that primarily affect patients with PIDs may significantly differ from those with acquired immunodeficiencies.Due to their lower susceptibility to available antifungal agents than A. fumigatus correct and prompt identification at the species level is critical for appropriate therapy to improve patient outcomes.In addition DNA sequence-based species identification targeting β-tubulin gene is more accurate than ITS and CaM genes and using MALDI-TOF to differentiate the emerging and cryptic Aspergillus species.

Identification of Causative agents associated with decay of Trees Twig and Orchards Die-back and their Impacts on Vessels of Citrus, Date Palm and Ficus

The present work is concerned with the studies of the organism causing wood decay of twigs and branches of citrus orchards, date palm Phoenix dactylifera L, and ficus trees. A survey for the occurrence of this disease in the main growing areas was achieved by the researchers. The following species of citrus orchards [lime (C. aurantifolia), sweet orange (C. sinensis), and mandarin (C. reticulate)] were surveyed, and so date palm and ficus trees. However, the results showed that the incidence of this disease was about 100%. Laboratory examinations data revealed mainly two fungal species causing the disease: Physalospora rhodina (P.rhodina) and Diaporthe citri (D. citri). In addition that, both fungi, which are P. rhodina and D. citri affected the vessels of tree tissues. According to the pathogenicity test, the fungus P. rhodina caused a breakdown of parenchyma cells, and the fungus D. citri caused the darkening of the xylem.

Prevalence, identification and frequency of uropathogens causing urinary tract infection in children in Ujjain (M.P.)

: Urinary tract infection is one of the most common infectious disease found in all population and has become a major health problem. The urinary tract infection also affects pediatric population especially in the age group of 0-5 years. The aim of this study to find out prevalence of UTI in children, its occurrence in different gender and seasons along with identification of causative agent of UTI in children in Ujjain. The study was carried out in SRL laboratory Ujjain center and total 881 suspected patients urine sample were collected and tested by conventional methods for prevalence of significant bacteriuria. It was seen that 550 samples were positive and out of these, positive case 111 belonged to children of 0-5 years of age. Thus, 20.18% positive cases were of children. The percentage of UTI in female children was high (54.0%) while in male children it was low (45.9%) and high number of cases were recorded in rainy season (39.6%), followed by summer and winter seasons which were (34.2%) and (26.1%) respectively. The six major uropathogens present in urine sample were isolated and identified and among them four were gram negative in which . , . , . , . were gram negative while and . and . were gram positive UTI causing bacteria in children. In our study frequency of . was highest (60.3%) while . was present in very low frequency (3.6%) so the prevention of UTI in children should be done by proper care of children by mothers.

Raman Spectroscopy-A Novel Method for Identification and Characterization of Microbes on a Single-Cell Level in Clinical Settings.

Rapid and accurate identification of pathogens causing infections is one of the biggest challenges in medicine. Timely identification of causative agents and their antimicrobial resistance profile can significantly improve the management of infection, lower costs for healthcare, mitigate ever-growing antimicrobial resistance and in many cases, save lives. Raman spectroscopy was shown to be a useful—quick, non-invasive, and non-destructive —tool for identifying microbes from solid and liquid media. Modifications of Raman spectroscopy and/or pretreatment of samples allow single-cell analyses and identification of microbes from various samples. It was shown that those non-culture-based approaches could also detect antimicrobial resistance. Moreover, recent studies suggest that a combination of Raman spectroscopy with optical tweezers has the potential to identify microbes directly from human body fluids. This review aims to summarize recent advances in non-culture-based approaches of identification of microbes and their virulence factors, including antimicrobial resistance, using methods based on Raman spectroscopy in the context of possible use in the future point-of-care diagnostic process.

Combating Bovine Mastitis in the Dairy Sector in an Era of Antimicrobial Resistance: Ethno-veterinary Medicinal Option as a Viable Alternative Approach.

Bovine mastitis (BM) is the traditional infectious condition in reared cattle which may result in serious repercussions ranging from animal welfare to economic issues. Owing to the high costs associated with preventative practices and therapeutic measures, lower milk output, and early culling, bovine mastitis is accountable for most of the financial losses suffered in cattle farming. Streptococcus agalactiae, Staphylococcus aureus, Streptococcus dysgalactiae and coliform bacteria are the predominant pathogens for bovine mastitis. In addition, the occurrence of BM has been linked to lactation stage and poor management, in the latter case, the poor stabling conditions around udder hygiene. BM occurs throughout the world, with varying rates of Streptococcus agalactiae infection in different regions. Despite the modern techniques, such as the appropriate milking practices that are applied, lower levels of pathogen vulnerability may help to prevent the development of the disease, BM treatment is primarily reliant on antibiotics for both prophylactic and therapeutic purposes. Nevertheless, as a result of the proliferation of bacterial agents to withstand the antibiotic effects, these therapies have frequently proven ineffectual, resulting in persistent BM. Consequently, alternative medicines for the management of udder inflammation have been researched, notably natural compounds derived from plants. This review focuses on BM in terms of its risk factors, pathogenesis, management, the molecular identification of causative agents, as well as the application of ethno-veterinary medicine as an alternative therapy.

Study of prevalence of theileriosis in cattle and evaluation of therapeutic efficacy of different commercially available drugs

The present study was carried out to detect the prevalence of theileriosis in cattle of Sadar, Singair and Ghior upazila in Manikganj district of Bangladesh and evaluate the therapeutic efficacy of Imidocarb dipropionate (Babenil®), Oxytetracycline (Renamycine®) and Gentamicin (Acigent®). The study was conducted for six months and during this study period a total of 150 cattle were examined, 10 were found to be infected with Theileria spp. On Geimsa stained blood smear examination, it was observed that the overall prevalence of theileriosis in cattle was recorded as 6.67%. Animals were screened on the basis of clinical signs like fever, anorexia, with or without superficial lymph node enlargement and blood smear examination for presence of Theileria spp. The prevalence of theileriosis in female was non significantly higher (7.50 %) than male (5.71%). In case of age group, the significantly highest prevalence (13.3%) was in adult cattle above 3 years age, followed by 4.00 % in the age group of 2 to less than 3 years old and 0.00 % in 6 months to 2 years which was not significant(p>0.05). The prevalence of theileriosis in respect of breed was non significantly (p>0.05) maximum in cross breed cattle (7.05 %) than in indigenous cattle (6.15%). After identification of causal agent, therapeutic effect of imidocarb dipropionate, oxytetracycline and gentamicin were tested and where highest recovery was found by administration of imidocarb dipropionate (70 %) can be successfully used in the treatment of theileriosis. Asian J. Med. Biol. Res. 2022, 8 (1), 1-8

Multiplex size marker (YEAST PLEX) for rapid and accurate identification of pathogenic yeasts.

BackgroundMultiple yeast species can cause human disease, involving superficial to deep‐seated infections. Treatment of these infections depends on the accurate identification of causative agents; however, reliable methods are not available in many laboratories, especially not in resource‐limited settings. Here, a new multiplex assay for rapid and low‐cost identification of pathogenic yeasts is described.MethodsA two‐step multiplex assay named YEAST PLEX that comprises of four tubes and identifies 17 clinically important common to rare yeasts was designed and evaluated. The set also provides PCR amplicon of unidentified species for direct sequencing. The specificity of YEAST PLEX was tested using 28 reference strains belonging to 17 species and 101 DNA samples of clinically important non‐target bacteria, parasites, and fungi as well as human genomic DNA. The method was further analyzed using 203 previously identified and 89 unknown clinical yeast isolates. Moreover, the method was tested for its ability to identify mixed yeast colonies by using 18 mixed suspensions of two or three species.ResultsYEAST PLEX was able to identify all the target species without any non‐specific PCR products. When compared to PCR‐sequencing/MALDI‐TOF, the results of YEAST PLEX were in 100% agreement. Regarding the 89 unknown clinical isolates, random isolates were selected and subjected to PCR‐sequencing. The results of sequencing were in agreement with those of YEAST PLEX. Furthermore, this method was able to correctly identify all yeasts in mixed suspensions.ConclusionYEAST PLEX is an accurate, low‐cost, and rapid method for identification of yeasts, with applicability, especially in developing countries.

Distribution of bacterial stalk rot disease of maize in India and identification of causal agent using biochemical and fliC gene based marker and its sensitivity against chemicals and bacterial antagonist

Distribution of bacterial stalk rot disease of maize in India and identification of causal agent using biochemical and fliC gene based marker and its sensitivity against chemicals and bacterial antagonist

Comparative study of manual conventional blood cultures versus automated blood culture system in cases of septicemia

: Blood cultures are a proven gold standard method for the identification of causative agents of bloodstream infections. Identification of causative organism along with antibiotic susceptibility plays a pivotal role in proposing suitable antibiotic therapy. Automated blood culture systems show improved monitoring of blood cultures by reducing the time and by ensuring more accurate results when compared to the conventional blood culture system.To isolate the organism from given blood samples of a suspected case of septicemia and to compare the results of conventional and automated blood culture systems and to study the antimicrobial susceptibility pattern of the pathogens isolated.A prospective study of 6 months period was conducted among 100 subjects attending the Department of Microbiology in a tertiary care hospital. Subjects with symptoms and signs of septicemia were included. 25ml of venous blood was drawn aseptically from the venipuncture site, of which 5ml of blood was inoculated into 50ml of Brain Heart Infusion bottle in conventional blood culture system and 10ml each into aerobic and anaerobic BACTEC PLUS bottle in Automated blood culture system BACTEC FX40.Overall, 48% and 60% of the samples revealed positive growth by the conventional and automated blood culture system BACTEC FX40, respectively. Gram Positive Cocci were 52.08% and Gram Negative Bacilli were 47.91% isolated by conventional blood culture system, whereas automated blood culture system BACTEC FX40 isolated 45% and 55%, respectively. Isolates were detected within 24-48hrs and 12-24 hrs by conventional and automated blood culture systems, respectively. The anti-microbial susceptibility pattern of the pathogens isolated was also recorded by Kirby Bauer disc diffusion method of antimicrobial susceptiblity testing.Automated blood culture systems are a trustworthy substitute to conventional blood culture systems. The automated blood culture systems being more sensitive and rapid in detecting septicemia in subjects acts as an appropriate means for the initial identification and detection of blood pathogens and improved provision of antimicrobial therapeutic options for septic Patients especially in Critical Care and Intensive Care Units where positive culture reporting is crucial.

Identification and characterization of Metarhizium majus isolated from the edible insect Protaetia brevitarsis in Korea

AbstractEdible insects are considered novel protein sources, and the edible insect breeding industry is growing rapidly. However, fungal pathogens are a major threat to this industry, and appropriate identification of causative agents is important for the development of antifungal agents. In 2019, strains of the fungal pathogen Metarhizium were isolated from infected second and third instar larvae of the economically important edible insect Protaetia brevitarsis, which were collected from separate farms in Gimhae‐si, Gyeongsangnam‐do, Korea. Based on morphological characteristics and multilocus phylogenetic analysis of the internal transcribed spacer region, and 5′‐region of gene encoding the 1‐α elongation factor, the fungal strains were identified as Metarhizium majus. Here, we report the detailed phylogenetic characteristics and morphological description of this species, which is prevalent in Korea. Identification of the principal disease‐causing agent can help develop disease prevention and antifungal strategies for application in edible insect‐rearing farms.

Differentiation of Aspergillus flavus from Aspergillus oryzae Targeting the cyp51A Gene.

Aspergillus flavus is one of the most important agents of invasive and non-invasive aspergillosis, especially in tropical and subtropical regions of the world, including Iran. Aspergillus oryzae is closely related to A. flavus, and it is known for its economic importance in traditional fermentation industries. Reports of infection due to A. oryzae are scarce. Several studies reported that differentiating these two species in clinical laboratories is not possible using MALDI-TOF or by targeting fungal barcode genes, such as Internal Transcribed Spacer (ITS) and β-tubulin (benA). The species-level identification of causative agents and the determination of antifungal susceptibility patterns can play significant roles in the outcome of aspergillosis. Here, we aimed to investigate the discriminatory potential of cyp51A PCR-sequencing versus that of the ITS, benA and calmodulin (CaM) genes for the differentiation of A. flavus from A. oryzae. In a prospective study investigating the molecular epidemiology of A. flavus in Iran between 2008 and 2018, out of 200 clinical isolates of A. flavus, 10 isolates showed >99% similarity to both A. flavus and A. oryzae. Overall, the ITS, β-tubulin and CaM genes did not fulfil the criteria for differentiating these 10 isolates. However, the cyp51A gene showed promising results, which warrants further studies using a larger set of isolates from more diverse epidemiological regions of the world.

Modern trends in identification of causative agents in infective endocarditis

Advances in the diagnosis and treatment of patients with infectious endocarditis are limited by the high frequency of cases with an unknown etiology and imperfection of microbiological (cultural) methods. To overcome these problems new approaches to the identification of infectious endocarditis pathogens were introduced, which allowed achieving certain positive results. However, it should be noted that despite the wide variety of diagnostic tools currently used, there is no ideal method for etiological laboratory diagnosis of infectious endocarditis. The article discusses the features and place of immunochemical, molecular biological (MALDI-TOF MS, real-time PCR, sequencing, in situ fluorescence hybridization, metagenomic methods, etc.), immunohistochemical methods, and their advantages and limitations.

English

BACKGROUND Mycoses are assuming greater significance both in developed and developing countries particularly due to advent of immunosuppressive drugs and diseases. Dermatophytosis is most common type of cutaneous fungal infections seen in man, though in past few decades non-dermatophytes are also assuming importance. Present study is undertaken to know the pattern of dermatophytosis from our region. METHODS An observational study was conducted on 150 samples of patients with complaints of superficial mycoses. Samples were processed for microscopy on potassium hydroxide (KOH) mount and culture on Sabouraud’s dextrose agar (SDA) with and without cycloheximide and chloramphenicol. Any growth was identified by conventional technique. RESULTS One hundred and fifty samples consisting of 86 skin and 64 nails were studied. Most samples were seen in rainy season and males were predominantly affected. Adults from age of 21 - 50 years were most commonly affected. Most common clinical presentation was tinea corporis (70.93 %). In dermatophytic causes, T. mentagrophytes (36.21 %), T. tonsurans (27.59 %) followed by T. rubrum (15.52 %) were common isolates. In non-dermatophytic causes, candida spp. followed by aspergillus spp. were commonest isolates. CONCLUSIONS Tinea corporis is found to be the commonest presentation. Along with dermatophytes, non-dermatophytic fungi are also emerging as the cause of superficial mycoses. In non-dermatophytic fungi, candida is the commonest species, which is now a days showing drug resistance; hence, identification of causative agent is important for correct and prompt treatment. KEY WORDS Dermatophytosis, Non-Dermatophytic Fungi, Dermatophytic Fungi

Metagenomics of black grains: new highlights in the understanding of eumycetoma.

Eumycetoma is a chronic subcutaneous granulomatousdisease that is endemic in Sudan and other countries. It can be caused by eight different fungal orders. The gold standard diagnostic test is culture, however, culture-independent methods such as imaging, histopathological and molecular techniques can support diagnosis, especially in cases of negative cultures. The amplicon-based internal transcribed spacer 2 metagenomic technique was used to study black grains isolated from 14 tissue biopsies from patients with mycetoma. Furthermore, mycological culture and surgical biopsy histopathological examinations of grains were performed. Madurella mycetomatis (n=5) and Falciformispora spp. (n=4) organisms were identified by culture and confirmed by metagenomics. Metagenomics recognised, at the species level, Falciformispora as Falciformispora tompkinsii (n=3) and Falciformispora senegalensis (n=1), while in culture-negative cases (n=5), Madurella mycetomatis (n=3), Falciformispora senegalensis (n=1) and Fusarium spp. (n=1) were identified. Interestingly, the metagenomics results showed a 'consortium' of different fungi in each sample, mainly Ascomycota phylum, including various species associated with eumycetoma. The microbial co-occurrence in eumycetoma showed the co-presence of Madurella with Trichoderma, Chaetomium, Malasseziales and Sordariales spp., while Falciformispora co-presented with Inocybe and Alternaria and was in mutual exclusion with Subramaniula, Aspergillus and Trichothecium. Metagenomics provides new insights into the aetiology of eumycetoma in samples with negative culture and into the diversity and complexity of grains mycobiota, calling into question the accuracy of traditional culture for the identification of causative agents.

Infectious bovine abortions: observations from an organized dairy herd.

Abortions in dairy animals can be caused by several infectious agents. Identification of the actual causal agent(s) is important for formulating suitable control strategies. A 3-year (2016-2018) longitudinal study was conducted in a dairy farm following an abortion storm in the mid- to late gestations. The investigation focused on the seven major infectious abortifacient in cattle, viz. bovine alphaherpesvirus-1 (BoHV-1), bovine viral diarrhoea virus (BVDV), Neospora caninum, Brucella abortus, Coxiella burnetii, Leptospira Hardjo, and Listeria monocytogenes. High seroprevalence was observed for BVDV (79.4%), Leptospira (70.5%), BoHV-1 (53.5%), and Brucella (45.0%) at the beginning of the investigation (August 2016). The incidence proportion increased for BVDV, Leptospira, and Brucella in the following years of the investigation. A strong association of Brucella seropositivity with history of abortion (OR = 3.27) was recorded. Incidence of BoHV-1 reduced during the period of study coincident with systematic IBR inactivated marker vaccination of the herd. Sixty-four abortion cases were investigated for the identification of causative agent(s) by microbial culture, serological (ELISA), and molecular detection (PCR/ real-time PCR). Antibodies to BVDV, Brucella, BoHV-1, Leptospira, Neospora, and Coxiella were detected in 63, 61, 56, 35, 5, and 6 aborting cattle, respectively. Real-time PCR/PCR of clinical specimens detected DNA of Brucella, BoHV-1, Coxiella, Leptospira, and Listeria in 34, 13, 12, 9, and 4 abortion cases, respectively. BVDV and Neospora were not detected in any specimen samples. Brucella abortus isolated from the farm was determined as ST1 by multi-locus sequence typing (MLST). DNA of multiple agents were detected in 21 of the 64 cases (43.75%). Overall, the data suggests, Brucella was the major causative agent, although multiple causative agents circulated in the farm.

Prevalence and incidence of idiopathic subglottic stenosis in southern and central Alberta: a retrospective cohort study

BackgroundSubglottic stenosis (SGS) is a reportedly rare disease that causes recurrent severe airway obstruction. Etiologies reported for SGS include idiopathic, iatrogenic, autoimmune, congenital, and traumatic, with variable ratios among different centres. From empiric observation, southern and central Alberta was hypothesized to have a disproportionate distribution of SGS driven by increased idiopathic SGS (iSGS) compared to previous literature. Identification of causative agents of iSGS will help understand and guide future management options, so this study aimed to characterize the demographics of SGS subtypes, define prevalence and incidence rates of iSGS in southern Alberta, and geographically analyze for clustering of iSGS prevalence.MethodsSGS patients from Alberta census divisions No. 1–9 and 15 were retrospectively reviewed. Patients were subtyped according to etiology of SGS and characterized. Idiopathic SGS prevalence and incidence was assessed; prevalence was further geographically segregated by census division and forward sortation area (FSA). Significant clustering patterns were assessed for using a Global Moran’s I analysis.ResultsFrom 2010 to 2019 we identified 250 SGS patients, who were substantially overrepresented by idiopathic patients (80.4%) compared to autoimmune (10.0%), iatrogenic (7.6%), congenital (1.2%), and traumatic (0.8%). The total iSGS prevalence was 9.28/100,000 with a mean annual incidence rate of 0.71/100,000 per year. Significant clustering was observed (Moran’s index 0.125; z-score 2.832; p = 0.0046) and the highest rates of prevalence were observed in southern Alberta and in rural communities heterogeneously dispersed around Calgary FSAs.ConclusionIn southern and central Alberta, iSGS patients were disproportionately over-represented in contrast to other subtypes with the highest prevalence in southern Alberta. There was a three-fold higher annual incidence compared to previous literature demonstrating the highest rates of disease reported worldwide. Future research aims to expand the geographical scope and to assess for demographic or environmental differences within significant clusters that may contribute to disease pathophysiology.Level of evidenceIII.Graphical

300. Pediatric Center Evaluation of the BioFire® Blood Culture Identification 2 Panel Versus the Original BioFire®FilmArray® Blood Culture Identification Panel for the Detection of Microorganisms and Resistance Markers in Positive Blood Cultures

BackgroundStudies show a rising annual incidence of severe sepsis, with bloodstream infections continuing to impact children. Rapid identification of causative agents and timely administration of targeted therapy can positively impact patient outcomes and improve antibiotic stewardship.The BioFire® Blood Culture Identification 2 (BCID2) Panel (BioFire Diagnostics, LLC), an updated version of the FDA-cleared BioFire® FilmArray® Blood Culture Identification (BCID) Panel, designed for use on positive blood cultures (PBCs), assesses 43 analytes, including 17 novel analytes (8 bacterial, 2 fungal, and 7 antimicrobial resistance genes), with a similar turnaround time.MethodsDe-identified residual PBCs for which clinician-ordered testing per standard of care (SoC) had been performed were enrolled and tested with an Investigation-Use-Only version of the BCID2 Panel. Only one positive bottle per patient was enrolled. Results of BCID2 and BCID were compared.Results116 PBCs (48 aerobic and 68 anaerobic) were evaluated using the BioFire BCID2 Panel and results were compared to the BioFire BCID Panel. Of the 116 cases, 103 were positive on both the BioFire BCID2 Panel and the BioFire BCID Panel. Ten cases were negative on both tests. While the two panels showed 97% agreement, three cases were discrepant. Using culture (SoC) as the tiebreaker, two cases were false positive and one case was false negative on the BioFire BCID Panel. In all three cases, results from culture and the BioFire BCID2 Panel were in agreement. As expected, no organisms were detected on the BioFire BCID2 Panel in PBCs from 10% (12/116) of PBC bottles where culture identified only organisms that are not part of the panel menu. With the BioFire BCID2 Panel’s expanded platform, two cases identified as Enterobacteriaceae on the BioFire BCID Panel were identified to the genus level on the BioFire BCID2 Panel; 31 cases detected to the genus level on the BioFire BCID Panel were identified to the species level on the BioFire BCID2 Panel.ConclusionOverall, the BioFire BCID2 Panel performed well against the BioFire BCID Panel for identification of bloodstream pathogens and provided additional discrimination of some pathogens to the genus or species level.Data presented are from assays that have not been cleared or approved for diagnostic use.Disclosures All Authors: No reported disclosures

Bacteriological study of blood stream infection (BSI) in ICU patients

Introduction: Blood stream infection is a most common health care associated infection causes significant disease and death worldwide. Patients are admitted to ICUs carry higher risk of nosocomial BSI than those who are admitted in other type of units. Early Identification of causative agents & their antibiotic sensitivity pattern are useful to reduce mortality & improve clinical outcome of the patients. Materials and Methods: A prospective study conducted in tertiary care hospital. During study all the patients monitor for nosocomial blood stream \ infection. Blood sample collected from suspected patient of blood stream infection for detection causative organism & antimicrobial susceptibility pattern. Result: A Total 620 samples were tested out of these 173 (27.90%) were positive growth in culture. Maximum number of blood stream infections were from paediatric ICU (69.62%), followed by Medical ICU (18.35%) and from surgical ICU (12.02%). In present study incidence of length of stay is more after five day of admission in ICU (68.35%). The incidence of blood stream infection due to gram positive organism was (51.28%). Among them Staphylococcus aureus 72 (45.56%) was most common organism. Gram negative organism were quite low (48.73%) among them Klebsiella spp. (16.45%) was most common. The antimicrobial susceptibility pattern of isolated organisms showed high resistance to routinely used antimicrobial agents. Conclusion: The systemic approach by studying the culture of organisms from the foci and blood culture and the antibiotic profile may help the clinician to select appropriate empirical antimicrobial agents. Keywords: Antimicrobial sensitivity, Causative organisms, Intensive care Units, Nosocomial blood stream infection.

English

Endometritis has recently become one of the most important infectious diseases in donkey breeding farms in China. However, so far, no research has been conducted to confirm the causative agents. In the present study, one breeding farm was selected as a research model for isolation and identification of causative agents and epidemiological investigation. Streptococcus equi subspecies zooepidemicus was isolated from the uterus of symptomatic and asymptomatic donkeys and identified by PCR and MALDI-TOF MS analysis. On the farm, the infection rate was 57.1%, which indicated that endometritis is a severe problem and needs to pay much attention to donkey breeding farms. Moreover, female donkeys without mating experience were all negative which suggested the transmitting route might be artificial insemination or related handlings. This study will lead to a great understanding of the causative agent and epidemiological characteristics for endometritis in intensive donkey breeding farms