Advances in rapid point-of-care virus testing.

Outbreaks of viral diseases seriously jeopardize people's health and cause huge economic losses. At the same time, virology provides a new perspective for biology, molecular biology and cancer research, and it is important to study the discovered viruses with potential applications. Therefore, the development of immediate and rapid viral detection methods for the prevention and treatment of viral diseases as well as the study of viruses has attracted extensive attention from scientists. With the continuous progress of science and technology, especially in the field of bioanalysis, a series of new detection techniques have been applied to the on-site rapid detection of viruses, which has become a powerful approach for human beings to fight against viruses. In this paper, the latest research progress of rapid point-of-care detection of viral nucleic acids, antigens and antibodies is presented. In addition, the advantages and disadvantages of these technologies are discussed from the perspective of practical application requirements. Finally, the problems and challenges faced by rapid viral detection methods and their development prospects are discussed.

Cycle threshold dynamics of non-severe acute respiratory coronavirus virus 2 (SARS-CoV-2) respiratory viruses.

OBJECTIVE: Many providers use severe acute respiratory coronavirus virus 2 (SARS-CoV-2) cycle thresholds (Ct values) as approximate measures of viral burden in association with other clinical data to inform decisions about treatment and isolation. We characterized temporal changes in Ct values for non-SARS-CoV-2 respiratory viruses as a first step to determine whether cycle thresholds could play a similar role in the management of non-SARS-CoV-2 respiratory viruses. DESIGN: Retrospective cohort study. SETTING: Brigham and Women's Hospital, Boston. METHODS: We retrospectively identified all adult patients with positive nasopharyngeal PCRs for influenza, respiratory syncytial virus (RSV), parainfluenza, human metapneumovirus (HMPV), rhinovirus, or adenovirus between January 2022 and March 2023. We plotted Ct distributions relative to days since symptom onset, and we assessed whether distributions varied by immunosuppression and other comorbidities. RESULTS: We analyzed 1,863 positive samples: 506 influenza, 502 rhinovirus, 430 RSV, 219 HMPV, 180 parainfluenza, 26 adenovirus. Ct values were generally 25-30 on the day of symptom onset, lower over the ensuing 1-3 days, and progressively higher thereafter with Ct values ≥30 after 1 week for most viruses. Ct values were generally higher and more stable over time for rhinovirus. There was no association between immunocompromised status and median intervals from symptom onset until Ct values were ≥30. CONCLUSIONS: Ct values relative to symptom onset for influenza, RSV, and other non-SARS-CoV-2 respiratory viruses generally mirror patterns seen with SARS-CoV-2. Further data on associations between Ct values and viral viability, transmissibility, host characteristics, and response to treatment for non-SARS-CoV-2 respiratory viruses are needed to determine how clinicians and infection preventionists might integrate Ct values into treatment and isolation decisions.

Nucleic acid hybridization-based detection of pathogenic RNA using microscale thermophoresis.

Infectious diseases are one of the world's leading causes of morbidity. Their rapid spread emphasizes the need for accurate and fast diagnostic methods for large-scale screening. Here, we describe a robust method for the detection of pathogens based on microscale thermophoresis (MST). The method involves the hybridization of a fluorescently labeled DNA probe to a target RNA and the assessment of thermophoretic migration of the resulting complex in solution within a 2 to 30-time window. We found that the thermophoretic migration of the nucleic acid-based probes is primarily determined by the fluorescent molecule used, rather than the nucleic acid sequence of the probe. Furthermore, a panel of uniformly labeled probes that bind to the same target RNA yields a more responsive detection pattern than a single probe, and moreover, can be used for the detection of specific pathogen variants. In addition, intercalating agents (ICA) can be used to alter migration directionality to improve detection sensitivity and resolving power by several orders of magnitude. We show that this approach can rapidly diagnose viral SARS-CoV2, influenza H1N1, artificial pathogen targets, and bacterial infections. Furthermore, it can be used for anti-microbial resistance testing within 2 h, demonstrating its diagnostic potential for early pathogen detection.

The intersection of virus infection and liver disease: A comprehensive review of pathogenesis, diagnosis, and treatment.

Liver disease represents a significant global burden, placing individuals at a heightened risk of developing cirrhosis and liver cancer. Viral infections act as a primary cause of liver diseases on a worldwide scale. Infections involving hepatitis viruses, notably hepatitis B, C, and E viruses, stand out as the most prevalent contributors to acute and chronic intrahepatic adverse outcome, although the hepatitis C virus (HCV) can be effectively cured with antiviral drugs, but no preventative vaccination developed. Hepatitis B virus (HBV) and HCV can lead to both acute and chronic liver diseases, including liver cirrhosis and hepatocellular carcinoma (HCC), which are principal causes of worldwide morbidity and mortality. Other viruses, such as Epstein-Barr virus (EBV) and cytomegalovirus (CMV), are capable of causing liver damage. Therefore, it is essential to recognize that virus infections and liver diseases are intricate and interconnected processes. A profound understanding of the underlying relationship between virus infections and liver diseases proves pivotal in the effective prevention, diagnosis, and treatment of these conditions. In this review, we delve into the mechanisms by which virus infections induce liver diseases, as well as explore the pathogenesis, diagnosis, and treatment of liver diseases. This article is categorized under: Infectious Diseases > Biomedical Engineering.

Prevalence and Clinical Impact of Respiratory Viral Infections from the STOP2 Study of Cystic Fibrosis Pulmonary Exacerbations.

Rationale: Rates of viral respiratory infection (VRI) are similar in people with cystic fibrosis (CF) and the general population; however, the associations between VRI and CF pulmonary exacerbations (PEx) require further elucidation.Objectives: To determine VRI prevalence during CF PEx and evaluate associations between VRI, clinical presentation, and treatment response.Methods: The STOP2 (Standardized Treatment of Pulmonary Exacerbations II) study was a multicenter randomized trial to evaluate different durations of intravenous antibiotic therapy for PEx. In this ancillary study, participant sputum samples from up to three study visits were tested for respiratory viruses using multiplex polymerase chain reactions. Baselines and treatment-associated changes in mean lung function (percent predicted forced expiratory volume in 1 s), respiratory symptoms (Chronic Respiratory Infection Symptom Score), weight, and C-reactive protein were compared as a function of virus detection. Odds of PEx retreatment within 30 days and future PEx hazard were modeled by logistic and Cox proportional hazards regression, respectively.Results: A total of 1,254 sputum samples from 621 study participants were analyzed. One or more respiratory viruses were detected in sputum samples from 245 participants (39.5%). Virus-positive participants were more likely to be receiving CF transmembrane conductance regulator modulator therapy (45% vs. 34%) and/or chronic azithromycin therapy (54% vs. 44%) and more likely to have received treatment for nontuberculous Mycobacterium infection in the preceding 2 years (7% vs. 3%). At study visit 1, virus-positive participants were more symptomatic (mean Chronic Respiratory Infection Symptom Score, 53.8 vs. 51.1), had evidence of greater systemic inflammation (log10 C-reactive protein concentration, 1.32 log10 mg/L vs. 1.23 log10 mg/L), and had a greater drop in percent predicted forced expiratory volume in 1 second from the prior 6-month baseline (5.8 vs. 3.6). Virus positivity was associated with reduced risk of future PEx (hazard ratio, 0.82; 95% confidence interval, 0.69-0.99; P = 0.034) and longer median time to next PEx (255 d vs. 172 d; P = 0.021) compared with virus negativity.Conclusions: More than one-third of STOP2 participants treated for a PEx had a positive test result for a respiratory virus with more symptomatic initial presentation compared with virus-negative participants, but favorable long-term outcomes. More refined phenotyping of PEx, taking VRIs into account, may aid in optimizing personalized management of PEx.Clinical trial registered with www.clinicaltrials.gov (NCT02781610).

Shotgun metagenomics to investigate unknown viral etiologies of pediatric meningoencephalitis.

INTRODUCTION: Meningoencephalitis in children poses a diagnostic challenge, as etiology remains unknown for most of patients. Viral metagenomics by shotgun sequencing represents a powerful tool for investigating unknown viral infections related to these cases. PATIENTS AND METHODS: In a two-year, reference-centre, retrospective study, we investigated the usefulness of viral metagenomics of cerebrospinal fluid (CSF) for the diagnosis of viral infectious meningoencephalitis in forty seven pediatric patients, forty of them previously tested negative with a routine neurologic panel of viral targets that included herpesvirus 1-3 and enterovirus. We enhanced the detection by targeting viral sequences by hybrid capture. Raw sequence data was analysed using three bioinformatics pipelines. RESULTS: Out of forty remaining children with meningoencephalitis of unknown viral etiology, a significant detection of viral nucleic acid by shotgun sequencing was found in twenty one, which was confirmed in ten of them by specific PCR: seven human endogenous retrovirus K113 (HER K113), one parechovirus 3, one human herpesvirus 5 (HHV5); one enterovirus B (Echovirus 9). The remaining eleven CSF were not confirmed by PCR: three rotavirus, one human herpesvirus 7 (HHV7), one influenza A, one mastadenovirus C, one sindbis virus, one torque teno virus, one human immunodeficiency virus 1 (HIV-1), one human alphaherpesvirus 3 (HHV3), one human alphaherpesvirus 2 (HHV2). CONCLUSIONS: Underutilization of currently available meningitis-encephalitis diagnostic techniques such as BioFire® FilmArray® is the main cause of undiagnosed cases of meningoencephalitis. However, in this study we detected uncommon viruses that should be considered, including virus, rotavirus, sindbis virus, influenza A virus and HHV7. No other viral sequences that could be readily linked to CNS inflammation were detected. Some findings may stem from reagent or sample contamination, as seen with papillomavirus; for others, the clinical relevance of the virus remains uncertain and should be substantiated by further studies, as is the case with endogenous retrovirus K113 virus. Online bioinformatics pipeline CZID represents a valuable tool for analysing shotgun sequencing data in cases of neurological conditions with unknown etiology. Altogether, this study highlights the potential of shotgun sequencing in identifying previously unknown viral neuropathogens and sheds light on the interpretation issues related to its application in clinical microbiology.

Effect of Viral Illness on Procalcitonin as a Predictor of Bacterial Infection in Febrile Infants.

OBJECTIVE: The impact of confirmed viral infections (CVI) on procalcitonin (PCT) levels in febrile infants aged 8-60 days with a bacterial illness (BI) is unknown. The objectives of the study were to (1) examine the association of CVI with PCT levels in patients with/without a concurrent BI, defined as bacteremia, meningitis, or urinary tract infection, and (2) assess PCT as a predictor of BI in infants with a concurrent CVI. METHODS: In this single-center, retrospective cohort study, we examined febrile infants aged 8-60 days presenting between January 1, 2018 and December 31, 2020. PCT levels were compared between groups, according to results of bacterial cultures and viral tests, using the Wilcoxon rank test. The prediction ability of PCT to detect BI with/without concurrent CVI was assessed by using area under the curve from logistic regression. RESULTS: Patients included: 404 BI-/CVI+, 73 BI+/CVI-, 48 BI+/CVI+, and 138 BI-/CVI-. Median PCT level in the BI+/CVI+ group was significantly lower when compared to BI+/CVI- (0.36 ng/mL vs 0.89 ng/mL), but significantly higher than the BI-/CVI- group (0.36 ng/mL vs 0.1 ng/mL). The presence of a CVI reduced the sensitivity of PCT in BI detection (68% vs 44%), with minimal impact specificity (93% vs 96%). CONCLUSIONS: In previously healthy febrile infants 8-60 days old, the presence of a CVI reduces the sensitivity of PCT BI detection without impacting its specificity. The impact of a CVI on PCT levels in febrile infants has implications for how this marker of infection should be considered when assessing risk of BI in infants.

Sequence-based diagnostics and precision medicine in bacterial and viral infections: from bench to bedside.

PURPOSE OF REVIEW: Nucleic acid sequence-based organism identification plays an important role in the diagnosis and management of transplant and cancer-associated infectious diseases. Here, we provide a high-level overview of advanced sequencing technologies, discuss test performance, and highlight unmet research needs with a focus on immunocompromised hosts. RECENT FINDINGS: Next-generation sequencing (NGS) technologies are powerful tools with a growing role in managing immunocompromised patients with suspected infection. Targeted NGS (tNGS) can identify pathogens directly from patient specimens, especially for mixed samples, and has been used to detect resistance mutations in transplant-related viruses (e.g. CMV). Whole-genome sequencing (WGS) is increasingly used for outbreak investigations and infection control. Metagenomic NGS (mNGS) is useful for hypothesis-free testing and can simultaneously assess pathogens and host response to infection. SUMMARY: NGS testing increases diagnostic yield relative to standard culture and Sanger sequencing but may be limited by high cost, turnaround times, and detection of unexpected organisms or commensals of uncertain significance. Close collaboration with the clinical microbiology laboratory and infectious diseases is recommended when NGS testing is considered. Additional research is required to understand which immunocompromised patients are most likely to benefit from NGS testing, and when testing should ideally be performed.

Host test based on tumor necrosis factor-related apoptosis-inducing ligand, interferon gamma-induced protein-10 and C-reactive protein for differentiating bacterial and viral respiratory tract infections in adults: diagnostic accuracy study.

OBJECTIVES: To assess the performance of a test (called BV), integrating the blood levels of three immune proteins into a score, to differentiate bacterial from viral infection among adults with suspected lower respiratory tract infection (LRTI). METHODS: Prospective diagnostic accuracy study, enrolling febrile adults >18 years with LRTI signs or symptoms for less than 7 days presenting to several hospitals' emergency departments in Israel. The main exclusion criterion was immunodeficiency. Reference standard diagnosis (bacterial/viral/indeterminate) was based on three experts independently reviewing comprehensive patient data including follow-up data. BV generated three results: viral infection or other nonbacterial condition (0 ≤ score < 35), equivocal (35 ≤ score ≤ 65) and bacterial infection including co-infection (65 < score ≤ 100). BV performance was assessed against the reference standard with indeterminate reference standard and equivocal BV cases removed. RESULTS: Of 490 enrolled patients, 415 met eligibility criteria (median age 56 years, interquartile range 35). The reference standard classified 104 patients as bacterial, 210 as viral and 101 as indeterminate. BV was equivocal in 9.6% (30/314). Excluding indeterminate reference standard diagnoses and equivocal BV results, BV's sensitivity for bacterial infection was 98.1% (101/103; 95% confidence interval 95.4-100), specificity 88.4% (160/181; 83.7-93.1) and negative predictive value 98.8% (160/162; 97.1-100). DISCUSSION: BV exhibited high diagnostic performance for febrile adults with suspected LRTI among patients with reference standard diagnoses of bacterial or viral LRTI.

Assessing Biomarkers in Viral Infection.

Current biomarkers to assess the risk of complications of both acute and chronic viral infection are suboptimal. Prevalent viral infections like human immunodeficiency virus (HIV), hepatitis B and C virus, herpes viruses, and, more recently, severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) may be associated with significant sequelae including the risk of cardiovascular disease, other end-organ diseases, and malignancies. This review considers some biomarkers which have been investigated in diagnosis and prognosis of key viral infections including inflammatory cytokines, markers of endothelial dysfunction and activation and coagulation, and the role that more conventional diagnostic markers, such as C-reactive protein and procalcitonin, can play in predicting these secondary complications, as markers of severity and to distinguish viral and bacterial infection. Although many of these are still only available in the research setting, these markers show promise for incorporation in diagnostic algorithms which may assist to predict adverse outcomes and to guide therapy.

A Novel Combination of Host Protein Biomarkers to Distinguish Bacterial From Viral Infections in Febrile Children in Emergency Care.

BACKGROUND: Distinguishing bacterial and viral infections based on clinical symptoms in febrile children attending the emergency department (ED) is challenging. The aim of this study is to determine a novel combination of host protein biomarkers and to assess its performance in distinguishing between bacterial and viral infection in febrile children attending EDs. METHODS: A literature search was performed to identify blood protein biomarkers able to distinguish bacterial and viral infections (May 2015-May 2019). We selected 7 protein biomarkers: Procalcitonin, TNF-related apoptosis-inducing ligand (TRAIL), interleukin (IL)-4, IL-6, Interferon gamma-induced protein-10 (CXCL-10), interferon-gamma and lipocalin 2 (LCN2). These were measured in blood plasma using a bead-based immunoassay in children with a confirmed bacterial or viral infection attending EDs in the Netherlands. We used generalized linear modeling to classify bacterial and viral infections and applied a previously developed feature selection algorithm to select the optimal combination of proteins. We performed a subgroup analysis of this protein signature in patients with C-reactive protein <60 mg/L, representing a clinically challenging diagnostic group. RESULTS: In total 102 children were included (N = 67 bacterial; N = 35 viral). Individual performance of the 7 biomarkers in classifying bacterial versus viral infections ranged from 60.8%-74.5% area under the receiver operator curve (AUC). TRAIL, LCN2 and IL-6 were identified as the best 3-protein signature with an AUC of 86% (95% CI: 71.3%-100%). In 57 patients with C-reactive protein levels <60 mg/L, the 3-protein signature had an AUC of 85.1% (95% CI: 75.3%-94.9%). CONCLUSION: We demonstrate a promising novel combination of 3 host protein biomarkers; TRAIL, LCN2 and IL-6, which performs well in classifying bacterial and viral infections in febrile children in emergency care.

The Clinical Performance of the BioCode Respiratory Pathogen Panel for the Detection of Viruses and Bacteria from Nasopharyngeal Swabs.

Early detection of microbial pathogens causing respiratory tract infection plays a crucial role in clinical management. The BioCode Respiratory Pathogen Panel (BioCode RPP) utilizes reverse transcriptase PCR (RT-PCR) in combination with barcoded magnetic beads to amplify, detect, and identify respiratory pathogens. This panel qualitatively detects and identifies 14 viruses, including influenza virus A with H1 pdm09, H1, and H3 subtyping; influenza B; respiratory syncytial virus (RSV); human metapneumovirus; parainfluenza virus 1; parainfluenza virus 2; parainfluenza virus 3; parainfluenza virus 4; coronavirus (229E, NL63, OC43, and HKU1); adenovirus; and human rhinovirus/enterovirus, and 3 bacteria, including Chlamydia pneumoniae, Mycoplasma pneumoniae, and Bordetella pertussis. Reproducibility, which was assessed with contrived specimens containing 12 targets at 3 clinical sites, with 2 operators at each site for 5 days, was 99.4% for Flu A H3 and Flu B, 98.9% for RSV, and 100% for the remaining 9 targets assayed. A multicenter clinical trial evaluated the performance of the BioCode RPP with 2,647 nasopharyngeal swab specimens from 5 geographically distinct sites and revealed comparable performance between the BioCode RPP and FilmArray Respiratory Panel (FA-RP). Specifically, the positive percent agreements (PPAs) for various pathogens ranged between 80.8% and 100% compared with the FA-RP (1.7 and 2.0). Negative percent agreement ranged from 98.4% to 100% for BioCode RPP. The BioCode RPP also offers scalable automated testing capability of up to 96 specimens in a single run with total sample-to-result time under 5 h. The invalid rate of the BioCode RPP on initial testing was 1.0% (26/2,649). IMPORTANCE Early detection of microbial pathogens causing respiratory tract infection plays a crucial role in clinical management. The BioCode Respiratory Pathogen Panel (BioCode RPP) is a high-throughput test that utilizes RT-PCR in combination with barcoded magnetic beads to amplify, detect, and identify 17 respiratory pathogens, including 14 viruses and 3 bacteria. This study summarizes data generated from a multicenter clinical trial evaluating the performance of the BioCode RPP on 2,647 nasopharyngeal swab specimens from five geographically distinct sites.

Detection of serum human neutrophil lipocalin is an effective biomarker for the diagnosis and monitoring of children with bacterial infection.

BACKGROUND: The study aimed to investigate the diagnostic efficiency of human neutrophil lipocalin (HNL) in bacterial infections in children. METHODS: This study included 49 pediatric patients with bacterial infections, 37 patients with viral infections, 30 patients with autoimmune diseases (AID) and 41 healthy controls (HCs). HNL, procalcitonin (PCT), C-reactive protein (CRP), white blood cell (WBC) and neutrophil counts were detected in the initial diagnosis and the following days. RESULTS: In the patients with bacterial infections, the levels of HNL, PCT, CRP, WBC and neutrophils were significantly increased than that of disease controls and HCs. The dynamic of these markers was monitored during antibiotic treatment. The level of HNL was decreased rapidly in patients with effective treatment, but maintained at high levels in deteriorated patients according to the clinical progression. CONCLUSIONS: HNL detection is an effective biomarker to identify bacterial infections from viral infections and other AIDs, and has potential value to evaluate the effect of antibiotic treatment in pediatric patients.

The expression of respiratory tract virus in pediatric glomerular disease: a retrospective study of 45 renal biopsy in China.

BACKGROUND: More attention has been put on the relationship between pediatric glomerular disease and respiratory tract virus infection. Children with glomerular illness, however, are uncommonly found to have biopsy-proven pathological evidence of viral infection. The purpose of this study is to determine whether and what kind of respiratory viruses are found in renal biopsy from glomerular disorders. METHODS: We used a multiplex PCR to identify a wide range of respiratory tract viruses in the renal biopsy samples (n = 45) from children with glomerular disorders and a specific PCR to verify their expression. RESULTS: These case series included 45 of 47 renal biopsy specimens, with 37.8% of male and 62.2% of female patients. Indications for a kidney biopsy were present in all of the individuals. In 80% of the samples, respiratory syncytial virus was discovered. Following that, the RSV subtypes in several pediatric renal disorders were found. There were 16 RSVA positives, 5 RSVB positives, and 15 RSVA/B positives, accounting for 44.4%, 13.9%, and 41.7%, respectively. Nephrotic syndrome samples made up 62.5% of RSVA positive specimens. The RSVA/B-positive was detected in all pathological histological types. CONCLUSIONS: Patients with glomerular disease exhibit respiratory tract viral expression in the renal tissues, especially respiratory syncytial virus. This research offers new information on the detection of respiratory tract viruses in renal tissue, which may facilitate the identification and treatment of pediatric glomerular diseases.

A spectrum of viral diseases in Odisha state, eastern India: An evidence-based analysis from 2010-2017.

Introduction: Emerging and re-emerging viral diseases are a major threat to public health. Odisha, being one of the coastal states in the country, reports many viral illnesses due to its typical geographical location. This study focuses on the prevalence of different viral diseases in the state of Odisha, India, from 2010-2017. Material and Methods: A total of 43,397 patients with clinical suspicion of viral diseases were screened for different viral etiologies during 2010-2017. The laboratory diagnosis was conducted by serology (ELISA) and RT-PCR for 24 different viruses, i.e., dengue, chikungunya, Japanese encephalitis, hepatitis A virus, hepatitis E virus, hepatitis B virus, hepatitis C virus, rotavirus, herpes simplex virus-1 and herpes simplex virus-2, Epstein-Barr virus, cytomegalovirus, and respiratory viruses. Patients were enrolled from sporadic hospital admissions and outbreaks under different categories as per clinical diagnoses like fever with rash, diarrhoea, encephalitis, jaundice, respiratory illness, and fever of unknown etiology. Results: The majority of patients belonged to exanthematous group, i.e., fever with rash (32.24%). The number of males was more in all categories except fever with rash, where females (53.34%) were more. Children <16 years of age were found to be the predominant age group for suspected viral diarrhoea (85.26%), encephalitis (76.96%), fever of unknown origin (40.16%), and respiratory infections (27.23%). Conclusion: Not only vector-borne diseases pose a threat to the Odisha state, but other viral illnesses have also emerged. This detailed report of different viral diseases in the state of Odisha will support public health management.

[Diagnosis of bacterial and viral infection by HNL, SAA, PCT and CRP combined test].

The value of combined detection of neutrophil apolipoprotein (HNL), serum amyloid A (SAA), procalcitonin (PCT) and C-reactive protein (CRP) in the differential diagnosis of bacterial and viral infectious diseases. A retrospective study was conducted to collect the clinical data of infected patients and healthy people in the clinical department of Shaanxi Provincial People's Hospital from September to December in 2022. 100 patients with confirmed infection were divided into bacterial infection group (n=50) and virus infection group (n=50), and 50 healthy people were selected as control group (n=50). Fasting venous blood was collected at the initial stage of admission or on the day of physical examination. HNL was detected by double antibody sandwich method, SAA and CRP were detected by nephelometry, and PCT was detected by chemiluminescence method. The efficacy of infection markers in the differential diagnosis of bacterial infection and viral infection in infected patients was evaluated. The receiver operating characteristic (ROC) curve was used to evaluate the diagnostic efficacy of HNL, SAA, PCT and CRP in bacterial and viral infectious diseases; Logistic regression was used to analyze the influence of each index on the diagnostic efficiency. The results showed that the levels of HNL (126.60±33.32) ng/ml, PCT (28.02±11.37) ng/ml and CRP (36.13±14.37) mg/L in bacterial infection group were significantly higher than those of HNL (47.72±15.94) ng/ml, PCT (1.27±0.40) ng/ml, CRP (18.77±10.66) mg/L in virus group and HNL (38.21±12.53) ng/ml, PCT (0.38±0.12) ng/ml and CRP (4.13±1.07) mg/L in control group. The level of HNL increased most significantly (F=89.228, P<0.05). The area under ROC curve (AUC) from large to small was HNL+SAA+PCT+CRP (0.976), HNL (0.907), PCT (0.885), CRP (0.856), SAA (0.790), SAA/CRP (0.733). The level of SAA/CRP in virus infection group (94.05±3.75) was significantly higher than that in bacteria group (17.70±3.69) and control group (3.89±1.50) (F=84.005, P<0.05). The area under ROC curve (AUC) from large to small was HNL+SAA+PCT+CRP (0.986), SAA/CRP (0.956), SAA (0.878), HNL (0.768), CRP (0.742), PCT (0.730). In conclusion, HNL has the best auxiliary diagnostic efficacy in bacterial infection, followed by PCT; SAA/CRP has the best auxiliary diagnostic efficacy in viral infection, followed by SAA; the combined detection of serum HNL, SAA, PCT and CRP may be helpful for the differential diagnosis of bacterial and viral infections.

Recent Developments in Electrochemical-Impedimetric Biosensors for Virus Detection.

Viruses, including influenza viruses, MERS-CoV (Middle East respiratory syndrome coronavirus), SARS-CoV (severe acute respiratory syndrome coronavirus), HAV (Hepatitis A virus), HBV (Hepatitis B virus), HCV (Hepatitis C virus), HIV (human immunodeficiency virus), EBOV (Ebola virus), ZIKV (Zika virus), and most recently SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2), are responsible for many diseases that result in hundreds of thousands of deaths yearly. The ongoing outbreak of the COVID-19 disease has raised a global concern and intensified research on the detection of viruses and virus-related diseases. Novel methods for the sensitive, rapid, and on-site detection of pathogens, such as the recent SARS-CoV-2, are critical for diagnosing and treating infectious diseases before they spread and affect human health worldwide. In this sense, electrochemical impedimetric biosensors could be applied for virus detection on a large scale. This review focuses on the recent developments in electrochemical-impedimetric biosensors for the detection of viruses.

Lactantes febriles menores de tres meses sin foco aparente: ¿es necesario cambiar la estrategia de evaluación?: probamos el step by step / Febrile infants of under three months of age without apparent focus: is it necessary to change the assessment strategy?: we tested the step-by-step approach / Lactentes febris com menos de três meses de idade e sem foco aparente: é necessário alterar a estratégia de avaliação?: tentamos o "passo a passo"

Introducción: la fiebre es un motivo muy frecuente de consulta y hasta en un 20% de los pacientes no se encuentra la causa. En el ámbito de la emergentología pediátrica clásicamente ha existido interés en homogeneizar la forma de evaluar los lactantes febriles menores de tres meses. Contar con un protocolo que permita detectar precozmente el niño que cursa una infección bacteriana invasiva (IBI) sin realizar conductas desproporcionadas es todo un desafío. Objetivo: evaluar y comparar la capacidad para identificar IBI en la pauta actual de fiebre sin foco (FSF) como en la estrategia step by step, en lactantes con FSF valorados en el DEP-CHPR. Material y métodos: estudio observacional, descriptivo, retrospectivo y de pruebas diagnósticas. Criterios de inclusión: lactantes menores de 90 días de vida que consultaron en 2017 y 2018 en DEP-CHPR con diagnóstico de FSF. Resultados: se incluyeron 261 lactantes evaluados con la pauta de FSF actual, en ellos se aplicó la estrategia step by step. El rango de edad fue de 84 días (4-88 días) con una media de 41 días. Sexo masculino 148 niños (56,7%). Se registraron 37 infecciones bacterianas (14,2%) de las cuales 3 fueron IBI (1,1%) y 34 fueron no-IBI (13,1%). La sensibilidad para step by step fue de 0,94% y de 0,89 para la pauta actual, con un VPN de 0,98 para ambas estrategias. Discusión: los lactantes menores de 3 meses son más susceptibles por características fisiológicas a infecciones bacterianas invasivas y cuanto más pequeño aumenta aún más la frecuencia. El step by step discrimina a menores de 1 mes en menores de 21 días y otro grupo de más de 21 días. Nuestra pauta no hace esta discriminación y realiza por igual laboratorio en sangre, orina y líquido cefalorraquídeo; realizando en ocasiones estudios cruentos no necesarios. Conclusiones: ambas estrategias aplicadas en esta población resultaron altamente sensibles para identificar infección bacteriana con un VPN elevado. La aplicación de step by step presenta como beneficio adicional evitar con seguridad la punción lumbar en recién nacidos entre los 21 y 28 días.

Introduction: fever is a very frequent reason for consultation and in up to 20% of patients the cause has not been found. In the field of pediatric emergentology, there has been a traditional interest in homogenizing the way of assessing febrile infants under three months of age. Having a protocol that enables early detection of children with IBIs without engaging in disproportionate procedures is a challenge. Objective: to evaluate and compare the ability to identify IBIs in the present FSF regimen as in the Step-by-Step strategy, in infants with FSF assessed at the Pereira Rossell Pediatric Hospital Center. Material and methods: observational, descriptive, retrospective study and diagnostic tests. Inclusion criteria: Infants under 90 days of age who consulted in 2017 and 2018 at the DEP-CHPR with a diagnosis of FSF. Results: 261 infants diagnosed with FSF regimen were included and they all received a Step-by-Step approach. The age range was 84 days (4 - 88) days with a mean of 41 days. Males 148 children (56.7%). There were 37 bacterial infections (14.2%), of which 3 were IBI (1.1%) and 34 were Non-IBI (13.1%). The sensitivity for the Step-by-Step approach was 0.94% and 0.89 for the current regimen, with a NPV of 0.98 for both strategies. Discussion: infants younger than 3 months-old are more susceptible due to physiological characteristics to invasive bacterial infections, and the younger they are, the higher the frequency. The Step-by-Step Approach splits children of under 1 month of age into those under or over 21 days of age. Our guideline does not make this discrimination and performs the same blood, urine and cerebrospinal fluid laboratory tests sometimes carrying out blood tests is not necessary. Conclusions: both approaches used in this population were highly sensitive to the identification of bacterial infections with a high NPV. The application of the "Step-by-Step" approach has the additional benefit of avoiding lumbar puncture to newborns of between 21 and 28 days of age.

Introdução: a febre é um motivo muito comum de consulta e em até 20% dos pacientes a causa não é encontrada. No campo da emergência pediátrica, tradicionalmente tem havido interesse em homogeneizar a forma de avaliação de lactentes febris menores de três meses de idade. Ter um protocolo que permita a detecção precoce de uma criança com IBI sem realizar procedimentos desproporcionais é um desafio. Objetivo: avaliar e comparar a capacidade de identificação de IBI na atual Diretriz da FSF e na estratégia Passo a Passo, em lactentes com FSF avaliados no DEP-CHPR. Material e métodos: estudo observacional, descritivo, retrospectivo e de testes diagnósticos. Critérios de inclusão: Lactentes com menos de 90 dias de idade que consultaram em 2017 e 2018 no Hospital Pediátrico Pereira Rossell do Uruguai com diagnóstico de FSF. Resultados: Foram incluídos 261 lactentes avaliados com a atual diretriz da FSF, nos quais foi aplicada a estratégia Passo a Passo. A faixa etária foi de 84 dias (4 - 88) dias com média de 41 dias. Sexo masculino 148 crianças (56,7%). Foram registradas 37 infecções bacterianas (14,2%), sendo 3 IBI (1,1%) e 34 Não IBI (13,1%). A sensibilidade para Passo a Passo foi de 0,94% e 0,89 para o esquema atual, com VPN de 0,98 para ambas estratégias. Discussão: crianças menores de 3 meses de idade são mais suscetíveis a infecções bacterianas invasivas devido às características fisiológicas e quanto menores, mais frequentes. O Passo a Passo separa crianças menores de 1 mês em dois grupos: menores de 21 dias e acima de 21 dias. Nossa diretriz não faz essa discriminação e realiza exames laboratoriais de sangue, urina e líquido cefalorraquidiano da mesma forma; às vezes realizando estudos de sangue que não são necessários. Conclusões: ambas as estratégias aplicadas nesta população foram altamente sensíveis para identificar infecção bacteriana com alto VPN. A aplicação do "Passo a Passo" apresenta como benefício adicional evitar a punção lombar em recém-nascidos entre 21 e 28 dias.

Use of serum procalcitonin (PCT) level and PCT mRNA expression as a potential clinical biomarker in cats with bacterial and viral infections.

OBJECTIVES: The aim of this study was to investigate the use of procalcitonin (PCT) as a biomarker in differentiating bacterial infections from viral infections in cats. In addition, the relationship between PCT and mortality rate was also examined. METHODS: Forty-five cats were included in the study. The cats were categorised into two groups: bacterial (n = 20) and viral (n = 25) infection. Serum PCT level and PCT mRNA expression were analysed from blood samples collected before treatment. RESULTS: Serum PCT level and PCT mRNA expression of the cats with presumed bacterial infection were higher than those with viral infection (P = 0.001 and P = 0.001, respectively). The receiver operating characteristic (ROC) curve analysis revealed an area under the ROC curve value of 0.888 for serum PCT and 0.850 for PCT mRNA expression. There was no statistically significant difference among respiratory, urinary and gastrointestinal tract infections regarding serum PCT level and PCT mRNA expression in the presumed bacterial infection group (P = 0.741 and P = 0.141, respectively). In the presumed bacterial infection group, serum PCT level and PCT mRNA expression in the non-surviving cats were higher than those of the surviving cats (P = 0.021 and P = 0.026, respectively). CONCLUSIONS AND RELEVANCE: Serum PCT level and PCT mRNA expression were considered efficient biomarkers in cats to distinguish a bacterial infection from a viral infection. Moreover, ROC curve analysis was highly accurate in the discriminative capacity of these two parameters. PCT level and PCT mRNA expression offer substantial assistance in an efficient therapeutic approach and in avoiding unnecessary antibiotic use in feline clinical practice, particularly in emergency patients and those with non-specific clinical signs, decreasing the mortality rate. However, it should be noted that these data are only research data. More detailed future studies are needed.

Using procalcitonin levels to predict infection and reduce unnecessary antibiotic usage in febrile children aged 3-36 months.

INTRODUCTION: High risk features including body temperature (BT) ≥ 39 °C, inactive appearance, white blood cells (WBC) ≥ 15,000 cells/mm3, or absolute band count (ABC) ≥ 1,500 cells/mm3 have low sensitivity and negative predictive value (NPV) to discriminate between bacterial and viral infections, leading to overuse of antibiotics. We aimed to determine whether procalcitonin (PCT) level ≥ 0.5 ng/mL can differentiate bacterial from viral infections. METHODOLOGY: The medical data of children aged 3 to 36 months who presented with fever without localizing signs or having initially undetermined cause of respiratory tract infection and/or non-mucus bloody diarrhea for 1 to 7 days and were hospitalized between January 2017 and December 2018 with one of the high-risk features were recorded. Children with an immunocompromised condition, who had previously received antibiotics, and/or had clinical sepsis were excluded. RESULTS: Non-serious bacterial infection (SBI) and SBI (occult bacteremia) were found in 17.2% and 4.5%, respectively. The proportions of children with high-risk features were not significantly different between children with and without bacterial infection, except for absolute band count which was significantly higher in the bacterial infection group (419 cells/mm3, IQR [0, 1429]) than the non-bacterial group (76 cells/mm3, IQR [0,455]). A PCT level ≥ 0.5 ng/mL had the highest sensitivity and NPV (100%, 100%, respectively) to predict bacterial infection when compared with the other high-risk features. CONCLUSIONS: Antibiotics can be safely withheld while waiting for hemoculture in acute febrile children with one of the high-risk features of bacterial infection with PCT level < 0.5 ng/mL.