scholarly journals Direct Detection of Pathogens in Bloodstream During Sepsis: Are We There Yet?

2019 ◽  
Vol 3 (4) ◽  
pp. 631-642 ◽  
Author(s):  
Linoj Samuel

Abstract Background Advances in medicine have improved our understanding of sepsis, but it remains a major cause of morbidity and mortality. The detection of pathogens that cause sepsis remains a challenge for clinical microbiology laboratories. Content Routine blood cultures are time-consuming and are negative in a large proportion of cases, leading to excessive use of broad-spectrum antimicrobials. Molecular testing direct from patient blood without the need for incubation has the potential to fill the gaps in our diagnostic armament and complement blood cultures to provide results in a timely manner. Currently available platforms show promise but have yet to definitively address gaps in sensitivity and specificity. Summary Significant strides have been made in the detection of pathogens directly from blood. A number of hurdles, however, remain before this technology can be adapted for routine use.

2000 ◽  
Vol 7 (6) ◽  
pp. 977-979 ◽  
Author(s):  
Kritsana Janyapoon ◽  
Sunee Korbsrisate ◽  
Hatairat Thamapa ◽  
Sittichai Thongmin ◽  
Suwattana Kanjanahareutai ◽  
...  

ABSTRACT A dot blot enzyme-linked immunosorbent assay (ELISA) with a monoclonal antibody specific to phase1-c Salmonella was developed for the direct detection of Salmonella entericaserovar Choleraesuis in blood cultures. This system was applied to the identification of serovar Choleraesuis, and the results were compared with those obtained by a conventional biochemical method. It was revealed that all 12 samples identified to be infected with serovar Choleraesuis were positive on testing by the ELISA. In contrast, 77 samples infected with bacteria commonly isolated from the blood were not reactive by the ELISA. The calculated sensitivity and specificity of the established assay are 100%.


2003 ◽  
Vol 127 (9) ◽  
pp. 1106-1111 ◽  
Author(s):  
Betty A. Forbes

Abstract Context.—In the mid-1980s, the polymerase chain reaction methodology for the amplification of minute amounts of target DNA was successfully developed and then introduced into clinical use; such technology has led to a revolution in diagnostic testing. Despite enormous advances in the detection of infectious agents by amplification methods, there are also limitations that must be addressed. Objective.—To highlight the pertinent steps and issues associated with the introduction of an amplification assay into a clinical microbiology laboratory as well as the subsequent ongoing activities following its introduction into routine laboratory use. Data Sources.—Data were obtained from literature searches from 1990 through September 2002 using the subject headings “polymerase chain reaction,” “molecular assays,” and “amplification” as well as publications of the National Committee for Clinical Laboratory Standards. Data Extraction and Synthesis.—Using the findings obtained from these studies and publications, the process of introducing a molecular assay into the clinical microbiology laboratory was broken down into 4 major components: (1) initial phase of assay development, (2) polymerase chain reaction assay verification in which analytic sensitivity and specificity is determined, (3) assay validation to determine clinical sensitivity and specificity, and (4) interpretation of results and ongoing, required activities. The approach, as well as the advantages and limitations involved in each step of the process, was highlighted and discussed within the context of the published literature. Conclusions.—The application of molecular testing methods in the clinical laboratory has dramatically improved our ability to diagnose infectious diseases. However, the clinical usefulness of molecular testing will only be maximized to its fullest benefit by appropriate and careful studies correlating clinical findings with assay results.


2021 ◽  
Vol 2 (3) ◽  
pp. 241-254
Author(s):  
Pasquale Pisapia ◽  
Francesco Pepe ◽  
Antonino Iaccarino ◽  
Roberta Sgariglia ◽  
Mariantonia Nacchio ◽  
...  

Lung cancer is the leading cause of cancer death worldwide. Despite the emergence of highly effective targeted therapies, up to 30% of advanced stage non-small cell lung cancer (NSCLC) patients do not undergo tissue molecular testing because of scarce tissue availability. Liquid biopsy, on the other hand, offers these patients a valuable opportunity to receive the best treatment options in a timely manner. Indeed, besides being much faster and less invasive than conventional tissue-based analysis, it can also yield specific information about the genetic make-up and evolution of patients’ tumors. However, several issues, including lack of standardized protocols for sample collection, processing, and interpretation, still need to be addressed before liquid biopsy can be fully incorporated into routine oncology practice. Here, we reviewed the most important challenges hindering the implementation of liquid biopsy in oncology practice, as well as the great advantages of this approach for the treatment of NSCLC patients.


2018 ◽  
Vol 56 (10) ◽  
Author(s):  
David W. Kimberlin

ABSTRACTIn their article in this issue of theJournal of Clinical Microbiology, S. R. Dominguez et al. (J Clin Microbiol 56:e00632-18, 2018,https://doi.org/10.1128/JCM.00632-18) describe the performance of PCR detection of herpes simplex virus (HSV) DNA versus viral culture in skin and mucosal samples from 7 neonates with HSV disease. This is a significant contribution to our understanding of the optimal diagnostic approach in babies being evaluated for neonatal HSV disease. Many diagnostic laboratories already have made the change to molecular diagnostics for skin and mucosal swab testing, however, in large part due to the labor costs associated with viral cultures. Thus, important studies such as this one are being conducted to support a decision that has already been made in many locations on mostly economic grounds. This small case series supports the decision to use molecular testing for samples from skin and mucosal sites, but larger studies are needed to more fully define the performance characteristics of PCR in this population. Since a false-positive result would commit a baby to months of management that would be unnecessary and have potential harm, it is critical to base diagnostic decision making on data that support the use of a specific test.


1990 ◽  
Vol 18 (2) ◽  
pp. 152-156 ◽  
Author(s):  
GARY P. WORMSER ◽  
IDA M. ONORATO ◽  
TAMAR J. PREMINGER ◽  
DAVID CULVER ◽  
WILLIAM J. MARTONE

2011 ◽  
Vol 78 (6) ◽  
pp. 1930-1935 ◽  
Author(s):  
Suzanne L. Hennigan ◽  
Jeremy D. Driskell ◽  
Naola Ferguson-Noel ◽  
Richard A. Dluhy ◽  
Yiping Zhao ◽  
...  

ABSTRACTMycoplasma gallisepticumis a bacterial pathogen of poultry that is estimated to cause annual losses exceeding $780 million. The National Poultry Improvement Plan guidelines recommend regular surveillance and intervention strategies to containM. gallisepticuminfections and ensure mycoplasma-free avian stocks, but several factors make detection ofM. gallisepticumand diagnosis ofM. gallisepticuminfection a major challenge. Current techniques are laborious, require special expertise, and are typically plagued by false results. In this study, we describe a novel detection strategy which uses silver nanorod array–surface-enhanced Raman spectroscopy (NA-SERS) for direct detection of avian mycoplasmas. As a proof of concept for use in avian diagnostics, we used NA-SERS to detect and differentiate multiple strains of avian mycoplasma species, includingAcholeplasma laidlawii,Mycoplasma gallinarum,Mycoplasma gallinaceum,Mycoplasma synoviae, andM. gallisepticum, including vaccine strains 6/85, F, and ts-11. Chemometric multivariate analysis of spectral data was used to classify these species rapidly and accurately, with >93% sensitivity and specificity. Furthermore, NA-SERS had a lower limit of detection that was 100-fold greater than that of standard PCR and comparable to that of real-time quantitative PCR. Detection ofM. gallisepticumin choanal cleft swabs from experimentally infected birds yielded good sensitivity and specificity, suggesting that NA-SERS is applicable for clinical detection.


2021 ◽  
Vol 1 (S1) ◽  
pp. s36-s36
Author(s):  
Connie Schaefer

Background: Blood culture is a crucial diagnostic tool for healthcare systems, but false-positive results drain clinical resources, imperil patients with an increased length of stay (and associated hospital-acquired infection risk), and undermine global health initiatives when broad-spectrum antibiotics are administered unnecessarily. Considering emerging technologies that mitigate human error factors, we questioned historically acceptable rates of blood culture contamination, which prompted a need to promote and trial these technologies further. In a 3-month trial, 3 emergency departments in a midwestern healthcare system utilized an initial specimen diversion device (ISDD) to draw blood cultures to bring their blood culture contamination rate (4.4% prior to intervention) below the 3% benchmark recommended by the Clinical & Laboratory Standards Institute. Methods: All emergency department nursing staff received operational training on the ISDD for blood culture sample acquisition. From June through August 2019, 1,847 blood cultures were drawn via the ISDD, and 862 were drawn via the standard method. Results: In total, 16 contamination events occurred when utilizing the ISDD (0.9%) and 37 contamination events occurred when utilizing the standard method (4.3%). ISDD utilization resulted in an 80% reduction in blood culture contamination from the rate of 4.4% rate held prior to intervention. Conclusions: A midwestern healthcare system experienced a dramatic reduction in blood culture contamination across 3 emergency departments while pilot testing an ISDD, conserving laboratory and therapeutic resources while minimizing patient exposure to unnecessary risks and procedures. If the results obtained here were sustained and the ISDD utilized for all blood culture draws, nearly 400 contamination events could be avoided annually in this system. Reducing unnecessary antibiotic use in this manner will lower rates of associated adverse events such as acute kidney injury and allergic reaction, which are possible topics for further investigation. The COVID-19 pandemic has recently highlighted both the importance of keeping hospital beds available and the rampant carelessness with which broad-spectrum antibiotics are administered (escalating the threat posed by multidrug-resistant organisms). As more ambitious healthcare benchmarks become attainable, promoting and adhering to higher standards for patient care will be critical to furthering an antimicrobial stewardship agenda and to reducing treatment inequity in the field.Funding: NoDisclosures: None


1976 ◽  
Vol 29 (2) ◽  
pp. 105 ◽  
Author(s):  
AA Gidley-Baird ◽  
BM Bindon

A solid-phase tube assay for measuring LH levels in mouse plasma is described. The assay utilizes an antiserum to ovine LH and ovine LH standards and it measures LH levels in 20 III of plasma with a sensitivity of less than 0�6 ng/m!. Various parameters affecting the sensitivity and specificity of the assay were investigated. Serial dilutions of plasma from pregnant mice, a pituitary homogenate from mice and plasma from hypophysectomized mice, injected subcutaneously with ovine LB, ran parallel with ovine LH standards in plasma from hypophysectomized mice and plasma with low LH levels from intact mice. Ovine TSH showed about 12 % cross reaction in the assay system, whilst rat FSH and prolactin and also ovine FSH, prolactin and GH showed practically no cross reaction. Measurements of plasma LH levels have been made in hypophysectomized mice after injection with different vehicles containing 10 or 50llg LH or 50llg FSH per animal. Daily measurements of LH levels throughout pregnancy in the mouse show a rise in LH level prior to implantation and a further rise around mid-pregnancy which drops off sharply to levels which remain fairly constant until parturition when there is another rise.


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