scholarly journals Advances in Environmental Detection and Clinical Diagnostic Tests for Legionella Species

Author(s):  
Rajeshwari Vittal ◽  
Juliet Roshini Mohan Raj ◽  
Ballamoole Krishna Kumar ◽  
Indrani Karunasagar

Abstract Legionella is a fastidious organism that is difficult to culture in the lab but is widely distributed in environmental, domestic, and hospital settings. The clinical manifestations due to Legionella infections range from mild fever to fatal pneumonia and multiorgan pathologies. Legionella outbreaks though prevalent globally are not reported in developing countries due to difficulties in isolating this organism and the lack of simple diagnostic protocols. Here, we review the literature from across countries to present various methods used to detect Legionella from environmental and clinical samples. We compare the sensitivity and the specificity of the conventional culture-based assays with the recent methods and discuss approaches to develop better detection and diagnostic tests. With better cost-effective detection techniques and regular monitoring of the susceptible sites, which may harbor Legionella colonies, most of the Legionella infections can be prevented. As a result, considerable burden, caused by Legionella infections, on the healthcare system, in especially economically weaker countries, can be mitigated.

2021 ◽  
Vol 39 (1) ◽  
pp. 26-30
Author(s):  
Jabin Akhter ◽  
MA Hassan Chowdhury

Introduction: Although Tuberculosis mostly affects lungs in about 85% cases, but can cause lesion almost in every part of the body. Extrapulmonary TB (EPTB) accounts for 15 to 20% which involves other parts of the body beside the lungs. There are several methods that can diagnose Pulmonary TB (PTB) conclusively , but extrapulmonary TB is very difficult to diagnose till now especially in resource limited settings. Though it is not communicable but diagnostic delay has made it significant cause of morbidity and mortality. The snidy was aimed to find out the Gene Xpert as one of the diagnostic tool for EPTB. Methods: A laboratory based descriptive cross sectional study was conducted over a period of  17  months  from January 2017 to May 2018 to ascertain the performance of Gene Xpert technique as a diagnostic tool for EPTB. Data were collected through checklist and a total of 77 clinical samples were collected purposively with prior infom,ed consent from suspected EPTB patients following ethical issues. Laboratory investigations were  perfomed  at Rhodolphe Merieux Laboratory, Chittagong, Bangladesh with Gene Xpert MTB/Ri f assay, conventional culture (LJ media) and Microscopy (ZN stain) for the presence of Mycobacteium tuberculosis (MTB). Results: Among the 77 samples from suspected cases, seven(9.09%) from CSF, one(!.29%) from pus and one(l .29%) from lymphnode specimens were positive by Gene Xpert MTB/Rif assay.Only one(1.29%) CSF specimen  was found to be culture and microscopy positive which was Gene Xpert positive also. Except one specimen from pus that is both Gene Xpert and microscopy positive but culture negative, no other specimens from EPTB cases were culture and microscopy positive. Conclusion: Diagnosis of EPTB is challenging in worldwide. As it is paucibacillary, routine diagnostic test in detecting MTB is difficult. Gene X pert showed promising outcome in early detection of life threatening EPTB cases like TB meningitis which is common in developing countries. JOPSOM 2020; 39(1): 26-30


2017 ◽  
Vol 11 (01) ◽  
pp. 98-101 ◽  
Author(s):  
Tiziana D'Inzeo ◽  
Giulia De Angelis ◽  
Barbara Fiori ◽  
Giulia Menchinelli ◽  
Flora Marzia Liotti ◽  
...  

Introduction: Culture is regarded as the gold standard for the detection of genital mycoplasma in clinical samples. Commercially available diagnostic kits, based on liquid broth cultures, provide interesting alternatives to conventional culture. We assessed the laboratory performances of Mycoplasma IES (IES), the Mycofast Revolution (REV) and Mycoplasma IST 2 (IST2) compared to A7 agar plates for the detection of Ureaplasma urealyticum and Mycoplasma hominis in clinical samples. Methodology: From April to July 2013, endocervical or vaginal samples were collected from sexually active women with abnormal vaginal discharge. Each specimen was tested in parallel using the three commercial kits and the A7 agar plates. Results: A total of 303 samples were included in this study, 35.6% (108/303) of which were positive on A7 plates. Sensitivities for the detection of U. urealyticum of IES, REV and IST2 were 100%, 96.2% and 95.3%, respectively while those for M. hominis were of 92.8%, 92.8% and 85.7%, respectively. Specificity was 100% for the 3 methods. Concerning antimicrobial susceptibility testing, full agreement between IES and REV was documented. Conclusions: The Mycoplasma IES kit was found to be equivalent or superior compared to other commercial culture-based assays for a rapid and accurate identification of U. urealyticum and M. hominis and detection of resistance. It might be considered a cost-effective tool for detection of these organisms, particularly attractive in developing countries.


2001 ◽  
Vol 47 (1) ◽  
pp. 110-117 ◽  
Author(s):  
Magnus Jonsson ◽  
Joyce Carlson ◽  
Jan-Olof Jeppsson ◽  
Per Simonsson

Abstract Background: Electrophoresis of serum samples allows detection of monoclonal gammopathies indicative of multiple myeloma, Waldenström macroglobulinemia, monoclonal gammopathy of undetermined significance, and amyloidosis. Present methods of high-resolution agarose gel electrophoresis (HRAGE) and immunofixation electrophoresis (IFE) are manual and labor-intensive. Capillary zone electrophoresis (CZE) allows rapid automated protein separation and produces digital absorbance data, appropriate as input for a computerized decision support system. Methods: Using the Beckman Paragon CZE 2000 instrument, we analyzed 711 routine clinical samples, including 95 monoclonal components (MCs) and 9 cases of Bence Jones myeloma, in both the CZE and HRAGE systems. Mathematical algorithms developed for the detection of monoclonal immunoglobulins (MCs) in the γ- and β-regions of the electropherogram were tested on the entire material. Additional algorithms evaluating oligoclonality and polyclonal concentrations of immunoglobulins were also tested. Results: CZE electropherograms corresponded well with HRAGE. Only one IgG MC of 1 g/L, visible on HRAGE, was not visible after CZE. Algorithms detected 94 of 95 MCs (98.9%) and 100% of those visible after CZE. Of 607 samples lacking an MC on HRAGE, only 3 were identified by the algorithms (specificity, 99%). Algorithms evaluating total gammaglobulinemia and oligoclonality also identified several cases of Bence Jones myeloma. Conclusions: The use of capillary electrophoresis provides a modern, rapid, and cost-effective method of analyzing serum proteins. The additional option of computerized decision support, which provides rapid and standardized interpretations, should increase the clinical availability and usefulness of protein analyses in the future.


Biosensors ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 94
Author(s):  
Nirmita Dutta ◽  
Peter B. Lillehoj ◽  
Pedro Estrela ◽  
Gorachand Dutta

Cytokines are soluble proteins secreted by immune cells that act as molecular messengers relaying instructions and mediating various functions performed by the cellular counterparts of the immune system, by means of a synchronized cascade of signaling pathways. Aberrant expression of cytokines can be indicative of anomalous behavior of the immunoregulatory system, as seen in various illnesses and conditions, such as cancer, autoimmunity, neurodegeneration and other physiological disorders. Cancer and autoimmune diseases are particularly adept at developing mechanisms to escape and modulate the immune system checkpoints, reflected by an altered cytokine profile. Cytokine profiling can provide valuable information for diagnosing such diseases and monitoring their progression, as well as assessing the efficacy of immunotherapeutic regiments. Toward this goal, there has been immense interest in the development of ultrasensitive quantitative detection techniques for cytokines, which involves technologies from various scientific disciplines, such as immunology, electrochemistry, photometry, nanotechnology and electronics. This review focusses on one aspect of this collective effort: electrochemical biosensors. Among the various types of biosensors available, electrochemical biosensors are one of the most reliable, user-friendly, easy to manufacture, cost-effective and versatile technologies that can yield results within a short period of time, making it extremely promising for routine clinical testing.


2014 ◽  
Vol 104 (3) ◽  
pp. 233-237 ◽  
Author(s):  
María José Iglesias Sánchez ◽  
Ana María Pérez Pico ◽  
Félix Marcos Tejedor ◽  
María Jesús Iglesias Sánchez ◽  
Raquel Mayordomo Acevedo

Background Dermatomycoses are a group of pathologic abnormalities frequently seen in clinical practice, and their prevalence has increased in recent decades. Diagnostic confirmation of mycotic infection in nails is essential because there are several pathologic conditions with similar clinical manifestations. The classical method for confirming the presence of fungus in nail is microbiological culture and the identification of morphological structures by microscopy. Methods We devised a nested polymerase chain reaction (PCR) that amplifies specific DNA sequences of dermatophyte fungus that is notably faster than the 3 to 4 weeks that the traditional procedure takes. We compared this new technique and the conventional plate culture method in 225 nail samples. The results were subjected to statistical analysis. Results We found concordance in 78.2% of the samples analyzed by the two methods and increased sensitivity when simultaneously using the two methods to analyze clinical samples. Now we can confirm the presence of dermatophyte fungus in most of the positive samples in just 24 hours, and we have to wait for the result of culture only in negative PCR cases. Conclusions Although this PCR cannot, at present, substitute for the traditional culture method in the detection of dermatophyte infection of the nails, it can be used as a complementary technique because its main advantage lies in the significant reduction of time used for diagnosis, in addition to higher sensitivity.


2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Raquel Herrero-Arias ◽  
Esperanza Diaz

Abstract Background Patients’ experiences with health providers and their diagnostic and treatment expectations are shaped by cultural health beliefs and previous experiences with healthcare services in home country. This study explores how Southern European immigrant parents navigate the Norwegian healthcare system, through its focus on how this group manage their expectations on diagnosis and treatment practices when these are unmet. Methods The study had a qualitative research design. Fourteen in-depth interviews and two focus group discussions with 20 Southern European immigrant parents were conducted in 2017 in three Norwegian municipalities. With the help of NVivo software, data were transcribed verbatim and coded. Following a thematic analysis approach to identify patterns in immigrants’ experiences with the Norwegian healthcare services, the codes were organized into two themes. Results The first theme includes immigrants’ expectations on diagnostic tests and medical treatment. Southern European immigrants expected more diagnostic tests and pharmacological treatment than what was deemed necessary by Norwegian health providers. Experiences with unmet expectations influenced how immigrants addressed their and their children’s healthcare needs. The second theme comprises immigrants’ experiences of seeking healthcare in Norway (attending medical consultations in the private sector, seeking immigrant healthcare providers, and navigating the healthcare through their Norwegian social networks). This category includes also the alternative solutions immigrants undertook when they were dissatisfied with the diagnosis and treatment practices they were offered in Norway (self-medication and seeking healthcare in home countries). Conclusions Cultural health beliefs and previous experiences with healthcare services from home country shaped immigrants’ expectations on diagnosis and treatment practices. This had great implications for their navigation through the healthcare system and interactions with health providers in the host country. The study suggests that successful inclusion of immigrants into the Norwegian healthcare system requires an acknowledgement of the cultural factors that influence access and use of healthcare services. Exploring immigrants’ perspectives and experiences offers important information to understand the challenges of cross-cultural healthcare and to improve communication and equitable access.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yi-Ning Dai ◽  
Wei Zheng ◽  
Qing-Qing Wu ◽  
Tian-Chen Hui ◽  
Nan-Nan Sun ◽  
...  

AbstractNovel coronavirus pneumonia (NCP) has been widely spread in China and several other countries. Early finding of this pneumonia from huge numbers of suspects gives clinicians a big challenge. The aim of the study was to develop a rapid screening model for early predicting NCP in a Zhejiang population, as well as its utility in other areas. A total of 880 participants who were initially suspected of NCP from January 17 to February 19 were included. Potential predictors were selected via stepwise logistic regression analysis. The model was established based on epidemiological features, clinical manifestations, white blood cell count, and pulmonary imaging changes, with the area under receiver operating characteristic (AUROC) curve of 0.920. At a cut-off value of 1.0, the model could determine NCP with a sensitivity of 85% and a specificity of 82.3%. We further developed a simplified model by combining the geographical regions and rounding the coefficients, with the AUROC of 0.909, as well as a model without epidemiological factors with the AUROC of 0.859. The study demonstrated that the screening model was a helpful and cost-effective tool for early predicting NCP and had great clinical significance given the high activity of NCP.


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
A Tsiachristas ◽  
H West ◽  
E.K Oikonomou ◽  
B Mihaylova ◽  
N Sabharwall ◽  
...  

Abstract Background The National Institute for Health and Care Excellence (NICE) updated their guidance for the management of patients with stable chest pain and recommended that all patients undergo computed tomography coronary angiography (CTCA). This update has sparked a great deal of debate, and was followed by upgrade of CTCA into a Class I indication in the recent ESC guidelines. The cost-effectiveness of using CTCA as first line investigation is still unclear. Purpose To describe the current clinical pathway of patients with stable chest pain presented to outpatient clinics, assess the compliance with the updated NICE guideline, and explore the costs and health outcomes of different non-invasive diagnostic tests in real-world clinical setting. Methods We used data of 4,297 patients who attended chest pain clinics in Oxford between 1 January 2014 and 31 July 2018. Data included clinical presentation (e.g. age and previous cardiovascular conditions), diagnostic tests, outpatient visits, hospitalization, and hospital mortality and was compared between 6 alternative first-line diagnostic tests. Multinomial regressions were performed to estimate the probability of receiving each alternative and the associated cost after adjusting for clinical presentation. A decision tree was developed to describe the clinical pathway for each alternative first-line diagnostic in terms of subsequent diagnostic tests and treatments and to estimate the associated costs and life days. Results The proportion of patients who received CTCA as first line diagnostic test increased from 1% in 2014 to 17% in 2018, while the publication of the updated NICE guidelines in 2016 led to a threefold increase in this proportion. CTCA is less likely to be provided as a first-line diagnostic to patients who are younger age, males, smokers, and have angina, PVD, or diabetes. The standardised rate of hospital admission was the lowest in the exercise ECG cohort (0.35 admissions per 1,000 life-days) followed by the CTCA cohort (0.40 admissions per 1,000 life-days) while the latter cohort had the lowest standardised rate of cardiovascular treatment (2.74% per 1,000 life days). Stress echocardiography and MPS were associated with higher costs compared with CTCA, other ECG, and exercise ECG after adjusting for clinical presentation and days of follow-up. CTCA is the pathway most likely to be cost-effective, even compared to exercise ECG, while the other diagnostic alternatives are dominated (i.e. they cost more for less life-days). Conclusions Currently, the updated NICE guidelines for stable chest pain are implemented only to a fifth of the cases in England. Our findings support existing evidence that CTCA is the most-cost effective first-line diagnostic test for this population. Hopefully, this will inform the debate around the implementation of the guidelines and help commissioning and clinical decision processes worldwide. Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): National Institute of Health Research Oxford Biomedical Research Centre


2021 ◽  
Vol 13 (2) ◽  
pp. 603
Author(s):  
Darija Gajić ◽  
Slobodan Peulić ◽  
Tim Mavrič ◽  
Anna Sandak ◽  
Črtomir Tavzes ◽  
...  

Sustainable approaches for retrofitting buildings for energy efficiency are becoming necessary in a time when the building sector is the largest energy consumer. Retrofitting building stock is effective for reducing global energy consumption and decreasing resource exploitation. Less developed EU member states and neighboring developing countries show reluctance towards healthy and renewable materials. Implementation of sustainable materials for energy retrofitting is slowed down due to gaps in legislation and effective strategic programs, availability of bio-based materials, lack of knowledge regarding use and maintenance of renewable products, and marketing lobbies. Use of bio-based materials in refurbishment is important due to their negative or low global warming potential (GWP), low primary energy (PEI) need for production, cost-effective benefits, and recycling/reuse potential. Role of environmentally friendly solutions and low-carbon economy growth is particularly relevant in developing countries, such as Bosnia-Herzegovina, that cannot afford innovative energy recovery systems, yet possess a significant amount of poorly managed building stock. This research aims to analyze frameworks regarding retrofitting of residential buildings in Bosnia-Herzegovina and Slovenia. The analysis tackles indirect causes, studies the legal background, and examines strategic frameworks; thus, it indicates potential barriers for implementation of recommended retrofitting solutions based on renewable materials.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Shan Wei ◽  
Esther Kohl ◽  
Alexandre Djandji ◽  
Stephanie Morgan ◽  
Susan Whittier ◽  
...  

AbstractThe COVID-19 pandemic has resulted in an urgent need for a rapid, point of care diagnostic testing that could be rapidly scaled on a worldwide level. We developed and tested a highly sensitive and robust assay based on reverse transcription loop mediated isothermal amplification (RT-LAMP) that uses readily available reagents and a simple heat block using contrived spike-in and actual clinical samples. RT-LAMP testing on RNA-spiked samples showed a limit of detection (LoD) of 2.5 copies/μl of viral transport media. RT-LAMP testing directly on clinical nasopharyngeal swab samples in viral transport media had an 85% positive percentage agreement (PPA) (17/20), and 100% negative percentage agreement (NPV) and delivered results in 30 min. Our optimized RT-LAMP based testing method is a scalable system that is sufficiently sensitive and robust to test for SARS-CoV-2 directly on clinical nasopharyngeal swab samples in viral transport media in 30 min at the point of care without the need for specialized or proprietary equipment or reagents. This cost-effective and efficient one-step testing method can be readily available for COVID-19 testing world-wide, especially in resource poor settings.


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