scholarly journals Direct DNA Sequencing-Based Analysis of Microbiota Associated with Hematological Malignancies in the Eastern Province of Saudi Arabia

2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Faisal M. Alzahrani ◽  
Ali Al-Amri ◽  
Saeed Sattar Shaikh ◽  
Muzaheed ◽  
Amer Ibrahim Alomar ◽  
...  
Keyword(s):  
Hematological Malignancies ◽  
Metagenomic Library ◽  
Bloodstream Infections ◽  
Molecular Methods ◽  
Rrna Gene ◽  
Viridans Streptococci ◽  
Volunteer Blood Donor ◽  
Direct Dna Sequencing ◽  
Specificity And Sensitivity ◽  
Polymicrobial Infections

Introduction. Bloodstream infections (BSI) among patients with hematological malignancies (HM) could predispose them to higher morbidity and mortality for various underlying conditions. Several microorganisms, either pathogenic or opportunistic normal human flora, could cause severe bacteremia and septicemia. While conventional methods have their own limitations, molecular methods such as next-generation sequencing (NGS) can detect these blood infections with more reliability, specificity, and sensitivity, in addition to information on microbial population landscape. Methodology. Blood samples from HM patients ( n = 50 ) and volunteer blood donor control individuals with no HM ( n = 50 ) were subjected to 16S rRNA gene amplification using standard PCR protocols. A metagenomic library was prepared, and NGS was run on a MiSeq (Illumina) sequencer. Sequence reads were analyzed using MiSeq Reporter, and microbial taxa were aligned using the Green Genes library. Results. 82% of the patients showed BSI with Gram-negative bacteria as the most predominant group. E. coli comprised a major chunk of the bacterial population (19.51%), followed by K. pneumoniae (17.07%). The CoNS and Viridans Streptococci groups are 17.07% and 14.63%, respectively. Other major species were S. aureus (9.75%), P. aeruginosa (7.31%), A. baumannii (4.87%), E. cloacae (4.87%), and P. mirabilis (4.87%). 34.14% of the cases among patients showed a Gram-positive infection, while 14.63% showed polymicrobial infections. Conclusion. Most of the BSI in patients were characterized by polymicrobial infections, unlike the control samples. Molecular methods like NGS showed robust, fast, and specific identification of infectious agents in BSI in HM, indicating the possibility of its application in routine follow-up of such patients for infections.

scholarly journals Clinical Relevance of the Microbiome in Odontogenic Abscesses

Biology ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 916
Author(s):  
Sebastian Böttger ◽  
Silke Zechel-Gran ◽  
Daniel Schmermund ◽  
Philipp Streckbein ◽  
Jan-Falco Wilbrand ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Oral Microbiome ◽  
Molecular Methods ◽  
Gene Analysis ◽  
Rrna Gene ◽  
16S Rrna Gene Analysis ◽  
Cultural Methods ◽  
Odontogenic Abscess ◽  
Polymicrobial Infections

Odontogenic abscesses are usually caused by bacteria of the oral microbiome. However, the diagnostic culture of these bacteria is often prone to errors and sometimes fails completely due to the fastidiousness of the relevant bacterial species. The question arises whether additional pathogen diagnostics using molecular methods provide additional benefits for diagnostics and therapy. Experimental 16S rRNA gene analysis with next-generation sequencing (NGS) and bioinformatics was used to identify the microbiome of the pus in patients with severe odontogenic infections and was compared to the result of standard diagnostic culture. The pus microbiome was determined in 48 hospitalized patients with a severe odontogenic abscess in addition to standard cultural pathogen detection. Cultural detection was possible in 41 (85.42%) of 48 patients, while a pus-microbiome could be determined in all cases. The microbiomes showed polymicrobial infections in 46 (95.83%) cases, while the picture of a mono-infection occurred only twice (4.17%). In most cases, a predominantly anaerobic spectrum with an abundance of bacteria was found in the pus-microbiome, while culture detected mainly Streptococcus, Staphylococcus, and Prevotella spp. The determination of the microbiome of odontogenic abscesses clearly shows a higher number of bacteria and a significantly higher proportion of anaerobes than classical cultural methods. The 16S rRNA gene analysis detects considerably more bacteria than conventional cultural methods, even in culture-negative samples. Molecular methods should be implemented as standards in medical microbiology diagnostics, particularly for the detection of polymicrobial infections with a predominance of anaerobic bacteria.

Prospective Application of Aptamer-based Assays and Therapeutics in Bloodstream Infections

2020 ◽  
Vol 20 (10) ◽  
pp. 831-840
Author(s):  
Weibin Li
Keyword(s):  
Pathogenic Bacteria ◽  
Genetic Diagnosis ◽  
Bloodstream Infections ◽  
High Specificity ◽  
Peptide Sequence ◽  
High Morbidity ◽  
Specificity And Sensitivity ◽  
Prospective Application ◽  
Small Molecule Therapeutics

Sepsis is still a severe health problem worldwide with high morbidity and mortality. Blood bacterial culture remains the gold standard for the detection of pathogenic bacteria in bloodstream infections, but it is time-consuming, and both the sophisticated equipment and well-trained personnel are required. Immunoassays and genetic diagnosis are expensive and limited to specificity and sensitivity. Aptamers are single-stranded deoxyribonucleic acid (ssDNA) and ribonucleic acid (RNA) oligonucleotide or peptide sequence generated in vitro based on the binding affinity of aptamer-target by a process known as Systematic Evolution of Ligands by Exponential Enrichment (SELEX). By taking several advantages over monoclonal antibodies and other conventional small-molecule therapeutics, such as high specificity and affinity, negligible batch-to-batch variation, flexible modification and production, thermal stability, low immunogenicity and lack of toxicity, aptamers are presently becoming promising novel diagnostic and therapeutic agents. This review describes the prospective application of aptamerbased laboratory diagnostic assays and therapeutics for pathogenic bacteria and toxins in bloodstream infections.

scholarly journals Substantial diagnostic impact of blood culture independent molecular methods in bloodstream infections: Superior performance of PCR/ESI-MS

2018 ◽  
Vol 8 (1) ◽  
Author(s):  
Athanasios Makristathis ◽  
Nicole Harrison ◽  
Franz Ratzinger ◽  
Manuel Kussmann ◽  
Brigitte Selitsch ◽  
...  
Keyword(s):  
Blood Culture ◽  
Bloodstream Infections ◽  
Molecular Methods ◽  
Superior Performance ◽  
Diagnostic Impact ◽  
Esi Ms ◽  
Culture Independent

scholarly journals The pCS20 PCR assay for Ehrlichia ruminantium does not cross-react with the novel deer ehrlichial agent found in white-tailed deer in the United States of America

2004 ◽  
Vol 71 (2) ◽  
Author(s):  
S.M. Mahan ◽  
B.H. Simbi ◽  
M.J. Burridge
Keyword(s):  
United States ◽  
High Specificity ◽  
Pcr Primers ◽  
The United States ◽  
Rrna Gene ◽  
The Novel ◽  
Pcr Assay ◽  
Ehrlichia Ruminantium ◽  
Cowdria Ruminantium ◽  
Specificity And Sensitivity

White-tailed deer are susceptible to heartwater (Ehrlichia [Cowdria] ruminantium infection) and are likely to suffer high mortality if the disease spreads to the United States. It is vital, therefore, to validate a highly specific and sensitive detection method for E. ruminantium infection that can be reliably used in testing white-tailed deer, which are reservoirs of antigenically or genetically related agents such as Ehrlichia chaffeensis, Anaplasma (Ehrlichia) phagocytophilum (HGE agent) and Ehrlichia ewingii. Recently, a novel but as yet unnamed ehrlichial species, the white-tailed deer ehrlichia (WTDE), has been discovered in deer populations in the United States. Although the significance of WTDE as a pathogen is unknown at present, it can be distinguished from other Ehrlichia spp. based on 16S rRNA gene sequence analysis. In this study it was differentiated from E. ruminantium by the use of the pCS20 PCR assay which has high specificity and sensitivity for the detection of E. ruminantium. This assay did not amplify DNA from the WTDE DNA samples isolated from deer resident in Florida, Georgia and Missouri, but amplified the specific 279 bp fragment from E. ruminantium DNA. The specificity of the pCS20 PCR assay for E. ruminantium was confirmed by Southern hybridization. Similarly, the 16S PCR primers (nested) that amplify a specific 405-412 bp fragment from the WTDE DNA samples, did not amplify any product from E. ruminantium DNA. This result demonstrates that it would be possible to differentiate between E. ruminantium and the novel WTDE agent found in white tailed deer by applying the two respective PCR assays followed by Southern hybridizations. Since the pCS20 PCR assay also does not amplify any DNA products from E. chaffeensis or Ehrlichia canis DNA, it is therefore the method of choice for the detection of E. ruminantium in these deer and other animal hosts.

scholarly journals Comparison of polymerase chain reaction and microscopy for the detection of Fasciola spp. in the fecal matter of domestic bovines in Kalasin Province, Thailand

2021 ◽  
pp. 2878-2882
Author(s):  
Sirikanda Thanasuwan ◽  
Anupong Tankrathok
Keyword(s):  
Polymerase Chain Reaction ◽  
False Negative ◽  
Economic Losses ◽  
Rrna Gene ◽  
28S Rrna ◽  
Chain Reaction ◽  
Fecal Matter ◽  
Specificity And Sensitivity ◽  
Polymerase Chain ◽  
Fasciola Spp

Background and Aim: Fasciola spp. are important foodborne trematodes and waterborne zoonotic parasites that cause health problems and economic losses worldwide, including in Thailand. Fasciola spp. are usually detected by sedimentation or the formalin-ethyl acetate concentration technique (FECT) under microscopy, which is less specific and sensitive. Accurate detection is important to detect real incidence for protection against and elimination of fasciolosis in the area. This study aimed to determine the distribution of Fasciola spp. and compare the specificity and sensitivity of FECT under microscopy to that of polymerase chain reaction (PCR) in cattle feces. Materials and Methods: The study was conducted in Kalasin Province, Thailand. Feces of 46 cattle were investigated for infection with Fasciola spp. To detect infection, FECT under microscopy and PCR amplification of the 28S rRNA gene of Fasciola spp. were used to identify egg parasites. Results: Feces of 16 of 46 (34.78%) cattle were positive for Fasciola spp. using FECT under microscopy, whereas PCR showed that 67.39% (31 of 46) were positive for Fasciola spp. False-negative results were as high as 32.61% when diagnosed under microscopy. Conclusion: This study confirmed the infection of cattle with Fasciola spp. in Kalasin Province, indicating that PCR demonstrated higher sensitivity and specificity when diagnosing infection. FECT under microscopy can still be used as a primary and traditional method for diagnosis. However, relapse cases of Fasciola spp. and Paramphistomum spp. should be diagnosed by microscopy combined with PCR. This is the first report on the molecular distribution of fecal samples in cattle in Kalasin Province.

scholarly journals Investigation of neglected protists Blastocystis sp. and Dientamoeba fragilis in immunocompetent and immunodeficient diarrheal patients using both conventional and molecular methods

2021 ◽  
Vol 15 (10) ◽  
pp. e0009779
Author(s):  
Fakhriddin Sarzhanov ◽  
Funda Dogruman-Al ◽  
Monica Santin ◽  
Jenny G. Maloney ◽  
Ayse Semra Gureser ◽  
...  
Keyword(s):  
Next Generation Sequencing ◽  
Gastrointestinal Symptoms ◽  
Molecular Methods ◽  
Clinical Samples ◽  
Rrna Gene ◽  
Next Generation ◽  
Dientamoeba Fragilis ◽  
Significant Difference ◽  
Generation Sequencing ◽  
Immunocompetent Patients

Introduction The clinical significance of Blastocystis sp. and Dientamoeba fragilis in patients with gastrointestinal symptoms is a controversial issue. Since the pathogenicity of these protists has not been fully elucidated, testing for these organisms is not routinely pursued by most laboratories and clinicians. Thus, the prevalence of these organisms and the subtypes of Blastocystis sp. in human patients in Turkey are not well characterized. This study aimed to determine the prevalence of Blastocystis sp. and D. fragilis in the diarrheic stool samples of immunodeficient and immunocompetent patients using conventional and molecular methods and to identify Blastocystis sp. subtypes using next generation sequencing. Material and methods Individual stool specimens were collected from 245 immunodeficient and 193 immunocompetent diarrheic patients between March 2017 and December 2019 at the Gazi University Training and Research Hospital in Ankara, Turkey. Samples were screened for Blastocystis sp. and D. fragilis by conventional and molecular methods. Molecular detection of both protists was achieved by separate qPCRs targeting a partial fragment of the SSU rRNA gene. Next generation sequencing was used to identify Blastocystis sp. subtypes. Results The prevalence of Blastocystis sp. and D. fragilis was 16.7% and 11.9%, respectively as measured by qPCR. The prevalence of Blastocystis sp. and D. fragilis was lower in immunodeficient patients (12.7% and 10.6%, respectively) compared to immunocompetent patients (21.8% and 13.5%, respectively). Five Blastocystis sp. subtypes were identified and the following subtype distribution was observed: ST3 54.4% (n = 37), ST2 16.2% (n = 11), ST1 4.4% (n = 3), ST6 2.9% (n = 2), ST4 1.5% (n = 1), ST2/ST3 11.8% (n = 8) and ST1/ST3 8.8% (n = 6). There was no statistically significant difference in the distribution of Blastocystis sp. subtypes between immunocompetent and immunodeficient patients. Conclusion and recommendation Our findings demonstrated that Blastocystis sp. and D. fragilis are commonly present in immunocompetent and immunodeficient patients with diarrhea. This study is the first to use next generation sequencing to address the presence of Blastocystis sp. mixed subtypes and intra-subtype variability in clinical samples in Turkey.

scholarly journals 478. Outcomes of Extended-Spectrum β-Lactamase-Producing Escherichia coli Bloodstream Infection in Neutropenic Patients with Hematological Malignancies

2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S233-S234
Author(s):  
Sadaf Aslam ◽  
James Denham ◽  
John Greene
Keyword(s):  
Hospital Stay ◽  
Hematological Malignancies ◽  
Average Length ◽  
Length Of Hospital Stay ◽  
Bloodstream Infections ◽  
Cancer Center ◽  
Mortality Data ◽  
E Coli ◽  
Extended Spectrum ◽  
Neutropenic Patients

Abstract Background Infections with extended-spectrum β-lactamase (ESBL) producing Enterobacteriaceae is an emerging problem leading to poor clinical outcomes and increased mortality. The purpose of this study was to determine the prevalence, risk factors and outcomes of ESBL-producing E. coli (EC) in bloodstream infections (BSIs) of neutropenic patients with hematological malignancies and compare the difference with Non-ESBL producing EC. Methods Through an IRB approved protocol, a retrospective cohort study was conducted at the H. Lee Moffitt Cancer Center from January, 2007 till October, 2017. Of the 310 records, who had +ive blood cultures for E. Coli, a total of 63 neutropenic patients with hematological malignancies were identified based on the bloodstream infections with ESBL-EC and Non ESBL EC. Data included demographics, underlying malignancy, type of bone marrow transplant, duration of neutropenia, antibiotics use pre and post culture, length of hospital stay, severity of infection, ventilator use, and mortality data. Results A total of 310 cases with hematological malignancy and neutropenia were reviewed, 63 were identified as +ive blood culture for E. coli. Out of the 63 cases, 17 were ESBL-EC +ive and 46 were non-ESBL-EC. The prevalence of ESBL-EC was highest in the year 2015 (29.4%) and decreased in the subsequent years (Figure 1). The mean ages of the two groups were 53.59 ±12.4 and 60.82 ± 11.1, respectively. The average length of stay for the ESBL-EC group was 26.59 ± 11.2 days, longer than the non-ESBL EC group 21.96 ± 11.2. Days of neutropenia in non-ESBL vs. ESBL EC were 9 days ± 8.3, and 19 days ± 22.0, respectively, P < 0.01). No differences were observed in the 30–60 day mortality and other outcomes listed in Table 1. Conclusion The prevalence of ESBL-EC was observed to be higher in patients who were neutropenic for longer duration, were older and resulted in longer hospital stay. Early identification and empirical therapy in neutropenic patients suspected to have ESBL-EC infection is crucial. Also, the infection with ESBL-EC was higher in the year 2015 and decreased in the subsequent years. After higher rates, perhaps infection control, lab reporting changes, antibiotic stewardship and transmission-based precautions might have played a role. Disclosures All authors: No reported disclosures.

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