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Maria Stella Graziani

Deputy Director
Martina Zaninotto

Associate Editors
Ferruccio Ceriotti
Davide Giavarina
Bruna Lo Sasso
Giampaolo Merlini
Martina Montagnana
Andrea Mosca
Paola Pezzati
Rossella Tomaiuolo
Matteo Vidali

EIC Assistant
Francesco Busardò

International Advisory Board Khosrow Adeli Canada
Sergio Bernardini Italy
Marcello Ciaccio Italy
Eleftherios Diamandis Canada
Philippe Gillery France
Kjell Grankvist Sweden
Hans Jacobs The Netherlands
Eric Kilpatrick UK
Magdalena Krintus Poland
Giuseppe Lippi Italy
Mario Plebani Italy
Sverre Sandberg Norway
Ana-Maria Simundic Croatia
Tommaso Trenti Italy
Cas Weykamp The Netherlands
Maria Willrich USA
Paul Yip Canada

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Via L. Temolo 4, 20126 Milano

Responsible Editor
Giuseppe Agosta

Editorial Secretary
Chiara Riva
Biomedia srl
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Tel. 0245498282


ISSN print: 0393 – 0564
ISSN digital: 0392- 7091

Articoli con TAG: COVID-19

Il valore della medicina di laboratorio nella pandemia da SARS-CoV-2
The value of laboratory medicine in SARS-CoV-2 outbreak
<p>Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) represents a challenge to all heathcare systems. It represents, however, a formidabile opportunity to highlight the value of laboratory medicine. Laboratory tests, in fact, play a key role in allowing the etiological diagnosis thanks to the reverse transcription-plymerase chain reaction (rRT-PCR) to detect the virus in nasopharingeal specimes as well as in other samples collected by using a flocked swab. The second essential contribution that laboratory tests are providing encompasses staging, prognostication and therapeutic monitoring of COVID-19. Finally, serological tests play a central role for surveillance purposes, for using plasma containing antibodies from recovered patients as experimental treatment and for better understanding the immune response to SARS-CoV-2 to eventually address vaccine developments.</p>
Biochimica Clinica ; 44(4) 001-002
Guida sintetica alla diagnostica della malattia da coronavirus 2019 (COVID-19)
Concise guide to coronavirus disease 2019 (COVID-19) diagnostics
<p>Several months after its emergence, the coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is still prepotently disrupting health, societies and economies worldwide. The current approach for diagnosing SARS-CoV-2 remains based on identification of viral RNA by means of molecular biology techniques in upper or lower respiratory tracts specimens. Nevertheless, the development of immune response against the virus may also provide valuable diagnostic information. The paradigmatic kinetics of anti-SARS-CoV-2 antibodies in patients with COVID-19 would allow to conclude that serological testing shall not replace viral RNA detection in diagnosing acute SARS-CoV-2 infection, but may instead remain an essential tool for identifying patients who have been infected and have developed an immune response, as well as for monitoring the progress of herd immunity. For this purpose, the choice of the antigens used for constructing the immunoassays appears critical, as these shall use epitopes towards which neutralizing antibodies could be generated. Other important aspects in serological testing encompass the absence of cross-reactivity with other coronaviruses, the ability to distinguish the antibody class (i.e. IgG, IgA and/or IgM), quantitative assessment, wide range of linearity and low imprecision at diagnostic thresholds. A finalaspect, almost essential for both clinical and public health purposes, is the evidence of analytical and clinical validation before each method enters clinical practice.</p>
Biochimica Clinica ; 44(4) 003-004
Mortalità da COVID-19: una epidemia senza denominatore. Ma conosciamo il numeratore?
COVID-19 death rate: an epidemic without a denominator. But what do we know about the numerator?
<p>Since many COVID-19 patients display few, if any, symptoms, assessing infection rate, hospitalization rate, and mortality rate is very challenging. Not only we do not know the denominator of these ratios, but in assessing the mortality rate, we also have problems to estimate the numerator. Between March and April 2020, Italy recorded 42633 excess deaths compared to the average of the five previous years. In the same period, 27 846 deaths were classified as due to COVID-19. Since the international definition of a COVID-19 case requires a microbiological confirmation of the presence of the virus, 34.7% of the excess deaths remain unexplained. Part of these may be COVID-19 deaths, left unconfirmed for the lack of a microbiological swab; but further deaths may be caused by delayed care of other diseases, due to the reluctance of many patients to visit the hospitals during the pandemic. The same apparent underestimation of COVID-19 deaths emerges for other European countries, with more evident differences in the United Kingdom and in the Netherlands. In other countries, the number of excess deaths is lower than the average of the previous years, probably due to a delay in recording deaths. In conclusion, we have uncertainty about the real number of victims of this pandemic; we will improve our knowledge when numbers will be no longer provisional, but there are areas where it is impossible to get the perfect assessment; however these figures are rather important to better face a possible further epidemic wave.</p>
Biochimica Clinica ; 44(4) 005-006
COVID-19 - Opinions
Iper-infiammazione e squilibrio del sistema renina-angiotensina-aldosterone in corso di COVID-19: una nuova ipotesi per il sospetto clinico di ipercoagulabilità e immuno-trombosi microvascolare
Hyperinflammation and derangement of renin-angiotensin-aldosterone system in COVID-19: A novel hypothesis for clinically suspected hypercoagulopathy and microvascular immunothrombosis.
<p>Early clinical evidence suggests that severe cases of coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), are frequently characterized by hyperinflammation, imbalance of renin-angiotensin-aldosterone system, and a particular form of vasculopathy, thrombotic microangiopathy, and intravascular coagulopathy. In this paper, we present an immunothrombosis model of COVID-19. We discuss the underlying pathogenesis and the interaction between multiple systems, resulting in propagation of immunothrombosis, which through investigation in the coming weeks, may lead to both an improved understanding of COVID-19 pathophysiology and identification of innovative and efficient therapeutic targets to&nbsp;reverse the otherwise unfavorable clinical outcome of many of these patients.</p>
Biochimica Clinica ; 44(4) 007-008
Diagnosi del diabete gestazionale durante l’emergenza COVID-19: semplificazione del protocollo
Biochimica Clinica ; 44(4) 009-010
COVID-19 e coagulazione: un legame indissolubile
Biochimica Clinica ; 44(4) 013-014
Il ruolo del laboratorio di coagulazione nel monitoraggio del trattamento eparinico dei pazienti con COVID-19
The role of laboratory monitoring in heparin treatment of COVID-19 patients
<p>Coronavirus disease 2019 (COVID-19) can be associated with serious clinical complications such as acute respiratory distress syndrome (ARDS), sepsis and multiple organ failure (MOF). A key event in the pathophysiology of ARDS is immunothrombosis, a process initiated by the innate immune system that provides a first line of defense for local control of infection. In its physiological form, immunothrombosis is intended to facilitate the recognition, containment and destruction of pathogens, thus protecting the integrity of the host without inducing significant collateral damage. The cytokine storm that occurs during COVID-19 induces often venous and arterial thrombotic events affecting different organs, not limited to the respiratory system. It is therefore necessary to introduce an anticoagulant treatment in patients with COVID-19 to prevent the onset and the extension of thrombotic events. The low molecular weight heparin (LMWH) is the first-choice drug recommended by the main international scientific societies; alternatively, unfractionated heparin (UFH) or fondaparinux can be used. The dosage of these drugs in patients with COVID-19 is still under discussion. The coagulation testing plays an important role in monitoring the efficacy and safety of UFH treatment; in the case of LMWHs, these usually do not require monitoring but, if alterations of renal function occur, it is important to perform the chromogenic determinations of the anti-Xa activity, paying a particular attention to the timing of sampling, the pre-analytical variables, calibration of the test and reference ranges.</p>
Biochimica Clinica ; 44(4) 017-018
Al “cuore” del quadro clinico di COVID-19
To the “heart” of the clinical picture of COVID-19
<p>Several studies document cardiac involvement in COVID-19 patients, as evidenced by cardiac biomarkers elevation. Hospitalized patients with cardiac involvement have a poorer prognosis, in terms of need for intensive care unit, or mortality. This paper provides a review of the wealth of literature on heart involvement in COVID 19. The majority of the available papers reports data from the Chinese experience and it is not clear at the moment whether the observations are related to really different populations of patients. The mechanism of the cardiac injury is likely multifactorial. There could be direct myocardial damage by the virus, but the few heart histologic specimens available do not evidence the presence of virus RNA in myocytes. The infection in the lungs may produce a cytokine storm which in turn could damage myocytes. Coagulation system is also affected by COVID-19: D-dimer is increased, while platelets are reduced in most studies, and both parameters relate directly with the risk of death. These alterations are probably the cause of the many cases of pulmonary embolism, venous thromboembolisms, and arterial embolism reported. Hypertension and previous cardiovascular diseases are also likely involved in the severity of the observed cardiac injury. Although all these mechanisms may play a role in cardiac involvement, the severe lung infection alone could justify cardiac damage, due to the simultaneous reduced supply and increased demand of myocardial oxygen. We still know very little about this new viral disease, but as knowledge is accumulating, the medical community will pinpoint the mechanism of cardiac involvement and find the optimal strategy to prevent its severe consequences.</p>
Biochimica Clinica ; 44(4) 019-020
Valutazione di IgG e IgM anti-SARS-CoV-2 su Maglumi 800 (Snibe)
Evaluation of Anti-SARS-CoV-2 immunoglobulin G and M on Snibe Maglumi 800
<p>Introduction: the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a due to new beta-coronavirus causing the pandemic called Coronavirus disease 2019 (COVID-19). The evaluation of the presence of immunoglobulin G and M anti-SARS-CoV-2 (IgG and IgM) is important to understand the epidemiology of the disease and to confirm the presence of the disease when clinical signs are present, but RNA is not detected.<br />Methods: leftover serum samples from different types of patients were used: sera from biobank collected in 2018 as negative controls; patients recovering from the disease as positive controls; patients presenting at the Emergency Room with a positive rhino-pharyngeal swab; patients in Intensive Care Units. Anti-SARS-CoV-2 IgG and IgM were measured with MAGLUMI 2019-nCoV IgM/IgG Kits on Maglumi 800.<br />Results: one out of 61 expected negative resulted positive, and 2 were borderline for IgG (95% specificity, 95%CI 89.6-100), 1 positive for IgM (98.4% specificity, 95%CI 95.2-100); one out of 41 expected IgG positive resulted negative (97.6% sensitivity, 95%CI 92.8-100). All the 13 Intensive Care patients were positive for IgG, 11 for IgM. IgG were negative in 50.9% of the 55 swab positive from Emergency Room patients, while IgM were negative in 87.3%.<br />Discussion: sensitivity and specificity of the test appear good for IgG, some false positive is expected and low antibody titles in subjects with no disease story should be rechecked with an alternative method. IgM show a good specificity, but the unexpected low percentage of positivity in Emergency Room patients compared to IgG, pose some relevant doubts on the sensitivity of the test.</p>
Biochimica Clinica ; 44(4) 025-026
Studio sulla presenza di componenti monoclonali in pazienti con infezione da SARS-CoV-2: dati preliminari
Presence of monoclonal components in SARS-CoV-2 patients: preliminary data
<p>Introduction: electrophoresis of serum proteins (EF) is indicated for the identification and monitoring of monoclonal components (CM). It has been shown that interleukins play a role in the differentiation of B cells in plasma cells producing immunoglobulins; it has been also demonstrated that COVID-19 patients show a higher prevalence of CM in comparison to the general population. The aim of this work is to retrospectively evaluate the presence of CM in patients hospitalized with COVID-19, compared to a population of patients admitted in non-COVID-19 wards.<br />Methods: EF was performed in the two groups of patients (COVID positive and negative) using capillary electrophoresis. Patients with previous plasma cell dyscrasias have been excluded.<br />Results: the results show that in the COVID positive group, the incidence of CM is statistically higher compared to the COVID negative group (39.7% versus 13.3%). In one patient, the CM was no longer detectable when the swab became negative.<br />Conclusions: the study confirmed that the viral infection produces detectable CM, probably transitory as shown by a case index. The pathogenesis of the phenomenon could be explained by the cytokine stimulus on B cells and by the interaction of the virus with the lymphocyte ACE 2 receptor. Larger studies are needed to confirm the presented data.</p>
Biochimica Clinica ; 46(1) 058-061
Contributi Scientifici - Scientific Papers
Biochimica Clinica ; 46(1) 074-077
Opinioni - Opinions
Longitudinal monitoring of anti-SARS-CoV-2 RBD IgG antibodies after BNT162b2 vaccination in healthcare workers
Biochimica Clinica ; 46(1) 083-085
Lettere all'Editore - Letters to the Editors
Cinetica e caratteristiche biologiche della risposta umorale all’infezione da SARS-CoV-2: implicazioni vaccinali
Kinetics and biological characteristics of humoral response developing after SARS-CoV-2 infection: implications for vaccination
<p>With the ongoing coronavirus disease 2019 (COVID-19) pandemic outbreak spreading all around the world, an extensive vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is now universally regarded as one of the most effective strategies for counteracting the unremittent spread of this novel coronavirus. Nonetheless, the reasonable need to identify segments of the population in which vaccination shall be prioritized for avoiding a possible shortage of vaccines seems to collide with indications provided by many national and international healthcare organizations, that endorse widespread vaccination irrespective of a positive history of prior symptomatic or asymptomatic SARS-CoV-2 infection. To this end, this document provides an ad interim guidance aimed at prioritizing SARS-CoV-2 vaccination in people who are more likely to be infected, re-infected and/or to develop more aggressive COVID-19 illness, essentially based on routine assessment and monitoring of anti-SARS-CoV-2 immune response.</p>
Biochimica Clinica ; 45(1) 087-090
Documenti SIBioC - SIBioC Documents
Raccomandazioni ad interim di SIBioC per l’analisi sierologica dell’infezione da SARS-CoV-2
Ad interim SIBioC recommendations for serological assessment of SARS-CoV-2 infection
<p>The recent pandemic outbreak caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and associated with the pathology called COVID-19 (coronavirus disease 2019), has now become one of the most strenuous health care challenges since the emergence of the three pandemics caused by influenza viruses during the past century. Throughout the clinical decision-making of COVID-19, laboratory tests are essential for supporting the screening, diagnosis, prognostication and therapeutic monitoring of this severe infectious disease. Serological testing, that reflects the humoral immune response developing after interaction between the host and the virus (or its components), enables to garner a vast array of clinical information which can be especially used in seroprevalence or seroconversion studies. To this end, the Task Force on COVID-19 of the Italian Society of Clinical Biochemistry and Clinical Molecular Biology (SIBioC) has endorsed a series of technical, practical and clinical ad interim recommendations, aimed at facilitating and optimizing the introduction, clinical usage and governance of SARS-CoV-2 serological immunoassays in routine practice.</p>
Biochimica Clinica ; 45(1) 091-099
Documenti SIBioC - SIBioC Documents
Antibody identification in COVID-19 pandemic: a comparison between immunochemiluminescence and immunochromatography methods
<p>Introduction: in the fight against the COVID-19 pandemic, the determination of the serum antibodies against SARS-CoV-2 is highly relevant, although the reliability of the results delivered is sometimes questionable. The aim of this paper is to evaluate the performances of a rapid immunochromatography test for IgG and IgM antibodies, comparing them with an immunochemiluminescence method.<br />Methods: we analyzed 357 sera for the presence of IgG anti-SARS-CoV-2 spike proteins S1/S2 with an automated immunochemiluminescent test (DiaSorin&reg;) and the presence of IgG and IgM anti-SARS-CoV-2 nucleocapside protein with an immunochromatography method (LEPU&reg;) based on lateral flow technology.<br />Results: with Diasorin&reg; method, 248 subjects resulted to be negative and 109 positives, whereas LEPU&reg; test was positive (IgM+ and/or IgG+) in 98 subjects. The overall concordance between LEPU&reg; and DiaSorin&reg;, was 94.1% (95% CI 91.0-96.2). Cohen&rsquo;s kappa was 0.86 (95% CI 0.80-0.92), indicating good agreement. 21 out of 357 (5.9%) samples had a discordant result and were re-analyzed with a third method (Roche Diagnostics Electrochemiluminescence&reg;): 4 out of 5 DiaSorin&reg; negative/LEPU&reg; positive samples were confirmed as negative by Roche&reg;; conversely, among the 16 DiaSorin&reg; positive/LEPU&reg; negative samples, 5 were confirmed as positive by Roche&reg;, 6 as negative and 5 were not retested due to insufficient sample volume.<br />Conclusions: despite the methods were designed to detect different antibodies an overall high agreement between techniques was found. Discrepant results were found and were likely due to different antigen targets recognized by methods. The observation that only 6 out of 11 DiaSorin&reg; positive samples were not confirmed by ROCHE&reg;, supports the antigen-dependent hypothesis.</p>
Biochimica Clinica ; 45(2) 153-157
Contributi Scientifici - Scientific Papers
Humoral response post-BNT162b2 single booster in pre-vaccination baseline SARS-CoV-2 seronegative and seropositive subjects
<p>Background: we report here data on humoral immune response post-BNT162b2 primary vaccination and booster in pre-vaccination baseline severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) seronegative and seropositive subjects. Methods: the study population consisted in 51 baseline SARS-CoV-2 seronegative and 11 baseline SARS-CoV-2 seropositive subjects, who underwent primary mRNA-based BNT162b2 vaccination (two doses) followed by homologous booster administration (third dose). Venous blood was sequentially collected up to 1 months after vaccine booster administration, and humoral response was monitored by measuring anti-SARS-CoV-2 spike trimeric IgG antibodies. Results: the humoral response after the three doses of BNT162b2 displayed an overlapping trend in the two groups, although the baseline and post-primary vaccination concentration of anti-SARS-CoV-2 spike trimeric IgG were constantly higher in baseline SARS-CoV-2 seropositive than in baseline SARS-CoV-2 seronegative subjects (all p&lt;0.001). Unlike before vaccine booster administration, the levels of anti-SARS-CoV-2 spike trimeric IgG, 1 month after receiving the third BNT162b2 dose were not significantly different between pre-vaccination baseline SARS-CoV-2 seropositive and seronegative subjects (7 430 versus 9 020 kBAU/L; p=0.232). In both cohorts, all recipients of vaccine booster displayed antibodies levels &gt;264 kBAU/L. Conclusion: the results of this study demonstrate that although baseline SARS-CoV-2 seropositive subjects have magnified humoral response to primary BNT162b2 vaccination, vaccine booster generates anti-SARS-CoV-2 spike trimeric IgG values not different from those found in baseline SARS-CoV-2 seronegative subjects. Thus, this study provides evidence that a prior SARS-CoV-2 infection does not mitigate the need for additional vaccine boosters.</p>
Biochimica Clinica ; 46(3) 209-212
Contributi Scientifici - Scientific Papers
La gestione del paziente in terapia anticoagulante orale in corso di pandemia: le soluzioni del Centro Emostasi e Trombosi di Savona
Monitoring of anticoagulant therapy during the COVID pandemic: the experience of the antithrombosis Centre in Savona (SV-Italy)
<p><span style="font-family:calibri,sans-serif; font-size:11.0pt">Introduction: the health emergency caused by the COVID-19 pandemic has forced health providers to rethink and reformulate patients&rsquo; care management, particularly during lockdown, in view of the need of stronger interactions between hospitals and local medical care with the aim of reducing the number of patients&rsquo; accesses to the hospitals. Patient under oral anticoagulant therapy, particularly those treated with antivitamin K drugs (AVK), need continuous therapy monitoring and drug dose adjustment, thus increasing their risk of possible SARS-CoV-2 exposure during the visits to the hospitals. The aim of this study is to illustrate, using appropriate indicators, the outcomes of an alternative clinical management of anticoagulated patients, adopting a new organizational model and an extended use of digital tools. Methods: a dedicated telephone number and a digital platform for therapy issuing were activated to maintain continuous patient surveillance and counselling activity. Specific indicators were: number of telephone calls received; number of digital therapy prescriptions; time in range (TTR) of AVK patients; number of major adverse events. Results: during the pandemic phase 10 215 telephone calls were received (with an increase of 200% compared to the pre-pandemic era). When compared to the values observed in the pre-pandemic period, the values of the indicators remained stable during the pandemic phase: TTR of AVK patients was 74% versus 74.6%; 22 minor and 2 major bleeding events were recorded versus 21 and 2 respectively. Discussion: the results obtained show, from the patient side, an optimal acceptance of the model proposed and, from the clinical side, the maintenance of the pre-pandemic quality standards of care</span></p>
Biochimica Clinica ; 46(3) 213-217
Contributi Scientifici - Scientific Papers
Test di generazione della trombina nella coagulopatia da COVID-19
Thrombin generation test in COVID-19 related coagulopathy
<p>Introduction: critically ill COVID-19 patients are known to have a coagulopathy characterized by increased levels of&nbsp; D-dimer (DD) associated to a thrombotic risk and a significant increase in mortality. However, it is not known whether the associated COVID-19 coagulopathy is due to a prothrombotic state or is caused by endothelial dysfunction and inflammation. Aim of our study, was to better characterize the hypercoagulability&nbsp; state of COVID-19 patients using Thrombin Generation analyser (ST Genesia&Acirc;&reg;, Diagnostica Stago, Asni&Atilde;&uml;res, France).<br />Methods: a total of 46 non-critically ill hospitalized COVID-19 patients were compared to 19 critically ill COVID-19 patients utilizing calibrated automated thrombography and other biochemical, hematological and coagulation parameters.<br />Results: critically ill patients had a significant increase in C reactive protein (CRP), interleukin-6 (IL-6), prothrombin time (PT), DD and a significant decrease in lymphocytes count. No significant differences in Thrombin Generation Test (TGT) parameters were&nbsp; observed between&nbsp; the two groups of patients with the only exception of the &acirc;&euro;&oelig;Lag Time&acirc;&euro; parameter.<br />Discussion: the obtained results confirmed increased levels of DD and PT in critically ill COVID-19 patients. Of note, disease severity did not cause an increase in Thrombin Generation when compared to non-critically COVID-19 patients. The significantly prolonged Lag Time in critically ill COVID-19 patients without decreased endogenous thrombin potential suggests an hypocoagulability state in these patients. The relevance of this finding is uncertain and may appear counterintuitive since these patients are expected to have a hypercoagulability status, and requires further research.</p>
Biochimica Clinica ; 46(4) 301-309
Contributi Scientifici - Scientific Papers
Dalla sepsi al COVID-19: il ruolo emergente di MDW
From sepsis to COVID-19: the emerging role of Monocyte Distribution Width (MDW).
<p><span style="color:#211D1E; font-size:9.0pt">Immune activation of the monocyte-macrophage population plays a pivotal role in the systemic hyper-inflammatory response, typically observed during severe dysimmune diseases, such as sepsis and COVID-19. In this commentary, we have reviewed the literature data on the novel cytometric marker of monocyte activation, known as MDW (Monocyte Volume Distribution Width), a monocyte dimensional parameter obtainable by blood count examination, which has recently been approved for clinical use as &ldquo;Early Sepsis Indicator&rdquo; (ESId), in patients accessing the Emergency Department. In particular, in this Opinion paper, we highlight the main clinical applications and relevant perspectives of this new test: from its use for (early) diagnosis of sepsis, in different hospital settings, to its emerging prognostic role in patients with COVID-19, as a biomarker of disease severity. In view of the reported evidence, we discuss the clinico-pathological notion that, basically, severe COVID-19 can be considered a new form of viral sepsis. Further clinical studies are needed to better understand the pre-analytical and analytical variables of this parameter, correlate MDW dynamics with those of other humoral and cytometric markers, and validate the new diagnostic and prognostic applications of MDW on large multicenter case series.</span></p>
Biochimica Clinica ; 46(4) 336
Opinioni - Opinions
Clinical assessment of FREND COVID-19 Ag test in an unselected population referred for routine SARS-CoV-2 testing
<p>Background: this observational retrospective study was aimed at evaluating the clinical performance of the novel microfluidic fluorescence immunoassay FREND COVID-19 Ag test in a population of unselected individuals undergoing routine SARS-CoV-2 (severe acute respiratory coronavirus 2) testing.<br />Methods: the study population consisted of a series of outpatients referred to the Service of Laboratory Medicine of Pederzoli Hospital (Peschiera del Garda, Verona, Italy) between April 12 and 30, 2021, for SARS-CoV-2 testing for being either symptomatic or having had close contact with one or more COVID-19 cases. A routine nasopharyngeal sample was collected at hospital admission and analyzed with both molecular (Altona Diagnostics RealStar&reg; SARS-CoV-2 RT-PCR Kit) and antigen (FREND COVID-19 Ag) tests.<br />Results: the area under the curve (AUC) of FREND COVID-19 Ag in all nasopharyngeal samples compared to molecular testing was 0.69 (95%CI, 0.64-0.75). At the &ge;1.0 TCID50/mL manufacturer&rsquo;s cut-off, accuracy, sensitivity, specificity, negative (NPV) and positive (PPV) predictive values were 61.3%, 0.27, 1.00, 0.55 and 1.00, respectively. The AUC of FREND COVID-19 Ag in samples with cycle threshold (Ct) values of both SARS-CoV-2 S and E genes &lt;29.5 was 1.00. At &ge;1.0 TCID50/mL (median tissue culture infective dose per mL) manufacturer&rsquo;s cut-off, accuracy, sensitivity, specificity, NPV and PPV values were 99.2%, 1.00, 0.99, 1.00 and 0.95, respectively.<br />Conclusions: FREND COVID-19 Ag could not replace routine molecular testing for achieving a definitive diagnosis of SARS-CoV-2 infection, but can be used as a surrogate test for identifying patients with higher nasopharyngeal viral load and thus greater infectious potential.</p>
Biochimica Clinica ; 45(4) 395-399
Contributi Scientifici - Scientific Papers
Elementi utili per implementare un sistema per il controllo dell'accuratezza dei risultati nella diagnostica di SARS-COV-2 (RNA virale, antigeni e anticorpi)
Useful elements for implementing a system to control the accuracy of results in the diagnosis of SARS-CoV-2 (viral RNA, antigens and antibodies)
<p>As SARS-CoV-2 swiftly spread globally becoming a pandemic, the urgent need to provide a laboratory diagnosis of the infection - to allow both the clinical management of individual patients and to monitor the outbreak in the community by health authorities - arose. This resulted in a rapid development of diagnostic tests - promptly available on the market - including methods for the direct detection of the virus in biological samples (molecular and antigenic tests) and for indirect detection by documenting a contact with SARS-CoV-2 (serological antibodies tests). To fast-track the availability of these tests, an &quot;emergency&quot; authorization was issued for their use in medical laboratories, which then resulted in the urge to verify their reliability and to monitor carefully their performances, in order to avoid the risk to provide inaccurate results. This document illustrates the main potential sources of error, which can be pre-pre-analytical (i.e. test utilization in an incorrect diagnostic window), pre-analytical (i.e. incorrect collection, manipulation, sample transport and storage), analytical (i.e. pipetting errors during manual sample dispensing, incorrect RNA extraction, cDNA synthesis and amplification) and post-analytical (i.e. incorrect test report and interpretation). Furthermore, the key elements for creating a system to keep continuously under control these potential sources of error are presented, both implementing an adequate control of the</p>
Biochimica Clinica ; 45(4) 400-407
Opinioni - Opinions