SARS‐CoV‐2 N‐antigenemia in critically ill adult COVID‐19 patients: Frequency and association with inflammatory and tissue‐damage biomarkers

Abstract The current study aimed at characterizing the dynamics of SARS‐CoV‐2 nucleocapsid (N) antigenemia in a cohort of critically ill adult COVID‐19 patients and assessing its potential association with plasma levels of biomarkers of clinical severity and mortality. Seventy‐three consecutive critically ill COVID‐19 patients (median age, 65 years) were recruited. Serial plasma (n = 340) specimens were collected. A lateral flow immunochromatography assay and reverse‐transcription polymerase chain reaction (RT‐PCR) were used for SARS‐CoV‐2 N protein detection and RNA quantitation and in plasma, respectively. Serum levels of inflammatory and tissue‐damage biomarkers in paired specimens were …

Field evaluation of a rapid antigen test (Panbio™ COVID-19 Ag Rapid Test Device) for the diagnosis of COVID-19 in primary healthcare centers

AbstractWe evaluated the Panbio™ COVID-19 AG Rapid Test Device (RAD) for the diagnosis of COVID-19 in symptomatic patients attended in primary healthcare centers (n=412). Overall specificity and sensitivity of RAD was 100% and 79.6%, respectively, taking RT-PCR as the reference. SARS-CoV-2 could not be cultured from specimens yielding RT-PCR+/RAD- results.

Point-of-care evaluation of a rapid antigen test (CLINITESTⓇ Rapid COVID-19 Antigen Test) for diagnosis of SARS-CoV-2 infection in symptomatic and asymptomatic individuals

AbstractRapid antigen assays (RAD) based on lateral flow immunochromatography (LFIC) technology have emerged as a valuable tool for the control of COVID-19 pandemic. Manufacturer□independent, real□world evaluation of these assays is crucial given the considerable heterogeneity reported in their clinical and analytical performances. Here, we report for the first time on the point-of-care performance of the CLINITEST® Rapid COVID-19 Antigen Test (Siemens, Healthineers, Erlangen, Germany) to detect SARS-CoV-2 infection in presumptive COVID-19 cases or asymptomatic close contacts of COVID-19 patients. When compared to RT-PCR, the overall sensitivity of the assay was 80.2 (95% CI, 70.9-87.1) for…

Amplification of human β-glucoronidase gene for appraising the accuracy of negative SARS-CoV-2 RT-PCR results in upper respiratory tract specimens

Real-time reverse transcription polymerase-chain reaction (RT-PCR) is the mainstay of Covid-19 diagnosis. False-negative RT-PCR results may hamper clinical management of patients and hinder the adoption of epidemiological measures to control the pandemic. The current study was aimed at assessing whether amplification of β-glucoronidase (GUSB) gene would help estimate the accuracy of SARS-CoV-2 RT-PCR negative results in upper respiratory tract (URT) specimens. URT specimens that tested negative by SARS-CoV-2 RT-PCR displayed higher GUSB RT-PCR cycle thresholds (CT) (P=0.070) than those testing positive (median, 30.7; range, 27.0-40.0, and median 29.7; range 25.5-36.8, respectively), this re…

Diagnostic significance of SARS-CoV-2 IgM positive/IgG negative antibody profile in symptomatic patients with suspected COVID-19 testing negative by RT-PCR

An outbreak of new coronavirus SARS-CoV-2 was occurred in Wuhan, China and rapidly spread to other cities and nations. The standard diagnostic approach that widely adopted in the clinic is nucleic acid detection by real-time RT-PCR. However, the false-negative rate of the technique is unneglectable and serological methods are urgently warranted. Here, we presented the colloidal gold-based immunochromatographic (ICG) strip targeting viral IgM or IgG antibody and compared it with real-time RT-PCR. The sensitivity of ICG assay with IgM and IgG combinatorial detection in nucleic acid confirmed cases were 11.1%, 92.9% and 96.8% at the early stage (1-7 days after onset), intermediate stage (8-14 …

Geographical and temporal structures of Legionella pneumophila sequence types in comunitat valenciana (Spain), 1998 to 2013

ABSTRACT Legionella pneumophila is an accidental human pathogen associated with aerosol formation in water-related sources. High recombination rates make Legionella populations genetically diverse, and nearly 2,000 different sequence types (STs) have been described to date for this environmental pathogen. The spatial distribution of STs is extremely heterogeneous, with some variants being present worldwide and others being detected at only a local scale. Similarly, some STs have been associated with disease outbreaks, such as ST578 or ST23. Spain is among the European countries with the highest incidences of reported legionellosis cases, and specifically, Comunitat Valenciana (CV) is the se…

Neisseria gonorrhoeae antimicrobial resistance in Spain: a prospective multicentre study.

Abstract Objectives Gonococcal infection is one of the most reported sexually transmitted infections and antimicrobial resistance in Neisseria gonorrhoeae (NG) is challenging for the treatment of this infection. This observational study aimed to describe antimicrobial resistance of NG and epidemiological data from patients with gonococcal infection in eight regions of Spain, for updating the local therapeutic guidelines. Methods MICs of penicillin, cefixime, ceftriaxone, azithromycin, ciprofloxacin, fosfomycin and gentamicin were determined by Etest for all NG isolates recovered from 1 April 2018 to 30 September 2019 from 10 hospitals in Spain. Resistance determinants were identified using …

Qualitative assessment of SARS-CoV-2-specific antibody avidity by lateral flow immunochromatographic IgG/IgM antibody assay.

Abstract Knowledge of the precise timing of SARS‐CoV‐2 infection may be of clinical and epidemiological relevance. The presence of low‐avidity IgGs has conventionally been considered an indicator of recent infection. Here, we carried out qualitative assessment of SARS‐CoV‐2‐specific antibody avidity using an urea (6M) dissociation test performed on a lateral flow immunochromatographic IgG/IgM device. We included a total of 76 serum specimens collected from 57 COVID‐19 patients, of which 39 tested positive for both IgG and IgM and 37 only for IgG. Sera losing IgG reactivity after urea treatment (n = 28) were drawn significantly earlier (P = .04) after onset of symptoms than those which prese…

Rotavirus-Specific Cytotoxic T Lymphocytes Recognize Overlapping Epitopes in the Amino-Terminal Region of the VP7 Glycoprotein

Abstract Rotavirus-specific cytotoxic T lymphocytes (CTL) play an important role in the resolution of rotavirus infection. The outer capsid glycoprotein, VP7, elicits a class I MHC-restricted CTL response. Vaccinia virus recombinants expressing the VP7 genes from simian rotavirus SA11 (serotype G3) and from the RF strain of bovine rotavirus (serotype G6) were used to analyze the CTL activity to this antigen in BALB/c (H-2 d ) and C57BL/6 (H-2 b ) mice neonatally infected with homologous and heterologous rotaviruses. A vaccinia virus recombinant expressing the first amino-terminal 88 amino acids of VP7 was constructed and used to search for cross-reactive CTL against this region of the prote…

SARS-CoV-2 RNA load in the lower respiratory tract, viral RNAemia and N-antigenemia in critically ill adult COVID-19 patients: relationship with biomarkers of disease severity

ABSTRACTBackgroundLittle is known about the comparative kinetics of SARS-CoV-RNA load in the lower respiratory tract and in blood compartment in patients admitted to the intensive care unit, and how these relate to biomarkers of COVID-19 severity.MethodsSeventy-three consecutive critically ill COVID-19 patients (median age, 65 years) were recruited. Serial lower respiratory tract (n=165) and plasma (n=340) specimens were collected. RT-PCR and lateral flow immunochromatography assay were used for SARS-CoV-2 RNA quantitation and N protein detection in plasma, respectively. Serum levels of inflammatory and tissue-damage biomarkers in paired specimens were analyzed.ResultsSARS-CoV-RNA was detec…

Multi-body-site colonization screening cultures for predicting multi-drug resistant Gram-negative and Gram-positive bacteremia in hematological patients

Abstract Background To investigate the multi-drug resistant bacteria (MDRB) colonization rate in hematological patients hospitalized for any cause using a multi-body-site surveillance approach, and determine the extent to which this screening strategy helped anticipate MDRB bloodstream infections (BSI). Methods Single-center retrospective observational study including 361 admissions documented in 250 adult patients. Surveillance cultures of nasal, pharyngeal, axillary and rectal specimens (the latter two combined) were performed at admission and subsequently on a weekly basis. Blood culture samples were incubated in an automated continuous monitoring blood culturing instrument (BACTEC FX). …

Viral proteins VP2, VP6, and NSP2 are strongly precipitated by serum and fecal antibodies from children with rotavirus symptomatic infection

Rotavirus-specific IgA has been correlated with immune protection against rotavirus reinfection and symptomatic disease. Systemic and mucosal antibody responses were determined by an enzyme-linked immunosorbent assay in 11 infants with severe rotavirus gastroenteritis. Geometric mean titers of antirotavirus serum IgG and IgA antibodies were significantly higher during the convalescence of the disease (P < 0.001 vs. acute-phase titers). Rotavirus-specific fecal sIgA antibodies increased 4 times during the convalescence in 9 (81.8%) children (P < 0.001). The serum IgG and IgA antibody and fecal sIgA antibody responses to individual rotavirus polypeptides were characterized by radioimmunopreci…

Mixed infection by Legionella pneumophila in outbreak patients.

During the molecular epidemiological study of a legionellosis outbreak, we obtained sequence based typing (SBT) profiles from uncultured respiratory samples of 15 affected patients. We detected several distinct allelic profiles some of which were a mixture of alleles present in the more common profiles. Chromatograms from the sequences of one patient with mixed profile showed polymorphisms in several positions, which could result from the simultaneous presence of different Legionella variants in the sample. In order to test this possibility, we cloned PCR amplification products from six loci for two patients with a mixed profile and a patient with a pure profile. After obtaining around 20 s…

Antibiotic susceptibility of Raoultella spp. in the Valencian Community: Results of Microbiological Surveillance Network for 4 years

Evaluation of a rapid antigen test (Panbio™ COVID-19 Ag rapid test device) for SARS-CoV-2 detection in asymptomatic close contacts of COVID-19 patients

Objectives There is limited information on the performance of rapid antigen detection (RAD) tests to identify SARS-CoV-2-infected asymptomatic individuals. In this field study, we evaluated the Panbio™ COVID-19 Ag Rapid Test Device (Abbott Diagnostics, Jena, Germany) for this purpose. Methods A total of 634 individuals (355 female; median age, 37 years; range, 9–87) were enrolled. Two nasopharyngeal swabs were collected from household (n = 338) and non-household contacts (n = 296) of COVID-19 cases. RAD testing was carried out at the point of care. The RT-PCR test used was the TaqPath COVID-19 Combo Kit (Thermo Fisher Scientific, MA, USA). Results Household contacts were tested at a median …

Non-wild-type cryptococcosis in a child with multivisceral organ transplant who owned bird pets.

Cryptococcosis is the third most common invasive fungal infection in solid-organ transplant recipients, although it is rarely reported in transplanted children. It typically appears as a late-onset infection with central nervous system or pulmonary involvement. We present a case of cryptococcosis caused by a non-wild strain in a 10-year-old child who owned two pet birds, and review the existent literature.

Comparison of two methods skipping cell lysis and protein extraction for identification of bacteria from blood cultures by matrix-assisted laser desorption/ ionization time-of-flight mass-spectrometry

ABSTRACT Objective Matrix-assisted laser desorption/ionization time-of-flight mass-spectrometry (MALDI-TOF MS) is widely used for fast identification of bacteria from blood cultures (BC). We compared the performance of two procedures, one including a pre-enrichment step in brain heart infusion and the other a direct method using vacutainer separator gel tubes (DI), for identification of bacteria from blood cultures by MALDI-TOF MS. Material and methods We first prepared a training set of 20 simulated bacteremia specimens, including 10 Gram-negative and 10 Gram-positive species. A total of 145 non-consecutive BCs flagged as positive (68 Gram-negative rods, and 77 Gram-positive cocci) were pr…

Parasitación asintomática por Diphyllobothrium latum en un niño español de 3 años

Perfil de sensibilidad antibiótica de Raoultella spp. en la Comunidad Valenciana: resultados de la Red de Vigilancia Microbiológica durante un período de 4 años

Field evaluation of a rapid antigen test (Panbio™ COVID-19 Ag Rapid Test Device) for COVID-19 diagnosis in primary healthcare centres.

Abstract Objectives To our knowledge no previous study has assessed the performance of a rapid antigen diagnostic immunoassay (RAD) conducted at the point of care (POC). We evaluated the Panbio™ COVID-19 Ag Rapid Test Device for diagnosis of coronavirus 2019 disease (COVID-19) in symptomatic patients (n = 412) attending primary healthcare centres. Methods RAD was performed immediately after sampling following the manufacturer's instructions (reading at 15 min). RT-PCRs were carried out within 24 h of specimen collection. Samples displaying discordant results were processed for culture in Vero E6 cells. Presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in cell cultures…

Co-detection of respiratory pathogens in patients hospitalized with Coronavirus viral disease-2019 pneumonia.

ABSTRACTThere is scarce information on the frequency of co-detection of respiratory pathogens (RP) in patients with Covid-19. Documentation of coinfections in Covid-19 pneumonia patients may be relevant for appropriate clinical and therapeutic management of patients. Between March 4th and March 28th, 2020, a total of 183 adult patients testing positive by SARS CoV-2 RT-PCR on respiratory specimens were hospitalized with interstitial pneumonia at our center, of whom 103 were tested for other RP by a multiplexed PCR assay. Three patients had a positive result for either one (n=2; Coronavirus HKU1 or Mycoplasma pneumoniae) or two targets (n=1; Influenza virus A (H3) and Respiratory syncytial v…

Real-life evaluation of a rapid antigen test (Panbio™ COVID-19 Ag Rapid Test Device) for SARS-CoV-2 detection in asymptomatic close contacts of COVID-19 patients

ABSTRACTObjectivesThere is limited information on the performance of rapid antigen detection (RAD) tests to identify SARS-CoV-2-infected asymptomatic individuals. In this field study, we evaluated the Panbio™ COVID-19 Ag Rapid Test Device (Abbott Diagnostics, Jena, Germany) for the purpose.MethodsA total of 634 individuals (355 female; median age, 37 years; range, 9-87) were enrolled. Household (n=338) contacts were tested at a median of 2 days (range, 1-7) after diagnosis of the index case and non-household contacts (n=296) at a median of 6 days (range, 1-7) after exposure. RAD testing was carried out at the point of care. The RT-PCR test used was the TaqPath COVID-19 Combo Kit (Thermo Fis…

Ceftolozane Pharmacokinetics in a Septic Critically Ill Patient under Different Extracorporeal Replacement Therapies

Ceftolozane-tazobactam (C/T), a novel fifth-generation cephalosporin/β-lactamase inhibitor combination active against multidrug-resistant (MDR) Pseudomonas aeruginosa, is currently approved by the U.S. Food and Drug Administration (FDA) to treat complicated intra-abdominal and urinary tract

Early adjustment of empirical antibiotic therapy of bloodstream infections on the basis of direct identification of bacteria by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and Gram staining results

Abstract Introduction To assess the potential added value of rapid MALDI-TOF MS-based identification of bacteria in positive blood cultures to the information provided by Gram staining for adequate empirical antibiotic treatment adjustments in patients with bloodstream infections (BSI). Methods We conducted a retrospective, single-center, pre-post quasi-experimental study. In the pre-MALDI-TOF MS phase of the study antibiotic adjustments were made on the basis of Gram stain results, whereas in the MALDI-TOF MS phase they were based on information provided by Gram staining and MALDI-TOF MS results. No antimicrobial stewardship program for BSI was in place within the study period. Antibiotic …

Upper respiratory tract SARS-CoV-2 RNA loads in symptomatic and asymptomatic children and adults

ABSTRACTObjectivesThere is limited information comparing SARS-CoV-2 RNA load in the upper respiratory tract (URT) between children and adults, either presenting with COVID-19 or asymptomatic. Here we conducted a retrospective, single center study involving a large cohort of SARS-CoV-2 infected individuals to address this issue.Patients and MethodsA total of 1,184 consecutive subjects (256 children and 928 adults) testing positive for SARS-COV-2 RNA in nasopharyngeal exudates (NP) were included, of whom 424 (121 children and 303 adults) had COVID-19 not requiring hospitalization and 760 (135 children and 625 adults) were asymptomatic close contacts of COVID-19 patients. SARS-CoV-2 RNA testin…

Evaluation of reverse transcription and polymerase chain reaction (RT/PCR) for the detection of rotaviruses: applications of the assay.

Summary Our aim was to evaluate the reverse transcription and polymerase chain reaction (RT/PCR) technique for the detection of rotavirus shedding by infected children as a routine diagnostic procedure, in comparison to the enzyme-linked immunosorbent assay (ELISA), electron microscopy (EM) and polyacrylamide gel etectrophoresis (PAGE) of rotavirus double stranded RNA. Two-hundred and twenty stool specimens were collected from infants and young children with diarrhoea, and 10–20% faecal suspensions were made. Several methods of rotavirus dsRNA extraction were assayed. Electrophoretic analysis of viral RNA was carried out on 10% polyacrylamide gols followed by silver staining. RT/PCR was per…