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1.
Clin Chim Acta ; 564: 119905, 2025 Jan 01.
Article in English | MEDLINE | ID: mdl-39127299

ABSTRACT

OBJECTIVES: The quality control of serological assays remains controversial. The aim of this project was to describe the problems associated with a working model for controlling these assays and solutions, including using a source of well-defined targets and acceptable limits, a process to identify lot-to-lot reagent variation and an interpretation of the result that accounted for the clinical situation. False-negative results are problematic but can be reduced by identifying and comparing reagent lot variation with previous results. METHODS: The components of the Quality Assurance strategy are the following: Lot-to-lot reagent and calibrator variation assessment; dynamic, big-data approach to determine accurate targets and acceptable limits for manufacturer-provided QC material; negative QC monitoring process; use of commutable EQA with a sufficient method subgroup size to assess bias; clinical assessment of any statistically flagged error; and provision of support to the clinician for the interpretation of results. RESULTS: The model described has been used for twelve months, and acceptable variation has been maintained. CONCLUSIONS: The paper presents a solution that emphasizes the early detection of reagent lot variation and patient risk rather than instrument control. Reducing the risk of a false result to patients requires optimal assay quality control and an effective mechanism to support the clinician's use of these results in diagnosis and monitoring. The problems of serological assays are well-known, but there remain few integrated solutions in the literature.


Subject(s)
Quality Control , Serologic Tests , Humans , Serologic Tests/standards
2.
Acta Trop ; 259: 107382, 2024 Nov.
Article in English | MEDLINE | ID: mdl-39244140

ABSTRACT

The diagnosis of Chagas disease mostly relies on the use of multiple serologic tests that are often unavailable in many of the remote settings where the disease is highly prevalent. In the Teniente Irala Fernández Municipality, in central Paraguay, efforts have been made to increase the diagnostic capabilities of specific rural health centres, but no quality assurance of the results produced has been performed. We comparatively analysed the results obtained with 300 samples tested using a commercial rapid diagnostic test (RDT) and enzyme linked immunosorbent assays (ELISA) at the laboratory of the Teniente Irala Fernández Health Center (CSTIF) with those generated upon repeating the tests at an independent well-equipped research laboratory (CEDIC). A subgroup of 52 samples were further tested at Paraguay's Central Public Health Laboratory (LCSP) by means of a different technique to evaluate the diagnostic performance of the tests carried out at CSTIF. We observed an excellent agreement between the ELISA results obtained at CSTIF and CEDIC (kappa coefficients between 0.85 and 0.93 for every kit evaluated), and an overall good performance of the tests carried out at CSTIF. However, the sensitivity of one kit was lower at CSTIF (81.3 %) than at CEDIC (100 %). The individual use of an RDT to detect the infection at CSTIF showed a similar sensitivity to that obtained combining it to an ELISA test (92.3% vs 88.5, p = 1). Nonetheless, the generalizability of this result is yet limited and will require of further studies.


Subject(s)
Chagas Disease , Primary Health Care , Rural Population , Sensitivity and Specificity , Serologic Tests , Paraguay , Humans , Chagas Disease/diagnosis , Serologic Tests/methods , Serologic Tests/standards , Adult , Male , Female , Quality Assurance, Health Care , Adolescent , Enzyme-Linked Immunosorbent Assay/methods , Enzyme-Linked Immunosorbent Assay/standards , Middle Aged , Child , Young Adult , Child, Preschool , Aged , Antibodies, Protozoan/blood
3.
Sci Rep ; 14(1): 18475, 2024 08 09.
Article in English | MEDLINE | ID: mdl-39122751

ABSTRACT

Hepatitis Delta Virus (HDV), a satellite virus of Hepatitis B virus, exacerbates liver damage in affected individuals. Screening for HDV antibodies in HBsAg positive patients is recommended, but the diagnostic accuracy of serological tests remains uncertain. This review aimed to assess the diagnostic accuracy of serological tests for HDV. We searched PubMed, Web of Science, Cochrane Central Register of Controlled Trials, Scopus etc. for relevant studies. Studies measuring the sensitivity and specificity of serological HDV tests against PCR as a reference standard were included. Pooled sensitivity and specificity for each test method and sero-marker were calculated. The review included six studies with 11 study arms, evaluating ARCHITECT immunoassay, EIA, ELISA, QMAC, RIA, and Western Blot test methods targeting Anti-HDV IgG, Total anti-HDV and Anti-HDV IgM. Sensitivities for Anti-HDV IgG, Total Anti-HDV and Anti-HDV IgM, tests were 97.4%, 51.9%, and 62.0%, respectively, with specificities of 95.3%, 80.0%, and 85.0%. Our findings, with its limited number of studies, suggest that HDV serological tests, particularly those identifying Anti IgG exhibit high accuracy and can serve as effective screening tools for HDV.


Subject(s)
Hepatitis D , Hepatitis Delta Virus , Sensitivity and Specificity , Serologic Tests , Humans , Hepatitis Delta Virus/immunology , Hepatitis D/diagnosis , Hepatitis D/virology , Hepatitis D/blood , Hepatitis D/immunology , Serologic Tests/methods , Serologic Tests/standards , Immunoglobulin G/blood , Hepatitis Antibodies/blood , Immunoglobulin M/blood
4.
Viruses ; 16(7)2024 Jul 03.
Article in English | MEDLINE | ID: mdl-39066237

ABSTRACT

In response to the 2015 Zika virus (ZIKV) epidemic that occurred in Brazil, numerous commercial serological assays have been developed for clinical and research applications. Diagnosis of recent infection in pregnant women remains challenging. Having standardized, comparative studies of ZIKV tests is important for implementing optimal diagnostic testing and disease surveillance. This is especially important for serology tests used to detect ZIKV infection given that antibodies against ZIKV can cross-react with other arboviruses in the same virus family, such as dengue virus (DENV), yellow fever virus (YFV) and West Nile virus (WNV). We looked at the sensitivity and specificity of tests detecting ZIKV antibodies (IgM, IgG) from multiple manufacturers using panels of samples previously collected with known exposure to ZIKV and other arboviruses. We found that performance of the IgM tests was highly variable, with only one test (Inbios 2.0 IgM capture ELISA) having both high sensitivity and specificity. All IgG tests showed good sensitivity; however, specificity was highly variable, with some assays giving false-positive results on samples infected by another flavivirus. Overall, the results confirmed that accurate ZIKV antibody testing is challenging, especially in specimens from regions endemic for multiple other flaviviruses, and highlight the importance of available and suitable reference samples to evaluate ZIKV diagnostics.


Subject(s)
Antibodies, Viral , Immunoglobulin G , Immunoglobulin M , Sensitivity and Specificity , Serologic Tests , Zika Virus Infection , Zika Virus , Humans , Zika Virus/immunology , Zika Virus Infection/diagnosis , Zika Virus Infection/immunology , Zika Virus Infection/blood , Antibodies, Viral/blood , Antibodies, Viral/immunology , Serologic Tests/methods , Serologic Tests/standards , Immunoglobulin M/blood , Immunoglobulin G/blood , Enzyme-Linked Immunosorbent Assay/methods , Enzyme-Linked Immunosorbent Assay/standards , Cross Reactions/immunology , Female , Pregnancy , Brazil
5.
Diagn Microbiol Infect Dis ; 110(2): 116451, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39053050

ABSTRACT

Sigma metric analysis was conducted across two New Zealand Blood Services (NZBS) laboratories (Auckland and Christchurch) to optimize quality control (QC) procedures. We evaluated five assays (anti-HCV, HIV Ag/Ab combo, HTLV-I/II, HBsAg, and Syphilis) using internal quality control (IQC) and third-party daily QC data extracted from four Architect i2000SR instruments during Jan 2 -31st, 2023. Mean, standard deviation (SD), and coefficient of variation (CV%) were calculated, assuming zero bias. Sigma metrics were determined using the Total Allowable Error (TEa %) based on difference between positive control mean and signal-to-cutoff (s/co) cut-off. Most assays exhibited CV% values ≤10 % except for HBsAg IQC (18.5 %) and anti-HCV third-party QC (13.4 %) at Christchurch. TEa % ranged from 38 % to 90 %. Overall, the assays demonstrated Six Sigma performance (σ > 6), except for HBsAg IQC (3.97) and anti-HCV third-party QC (5.46) at Christchurch. These high-quality serology assays can benefit from simplified QC design without compromising blood safety.


Subject(s)
Serologic Tests , Humans , New Zealand , Serologic Tests/standards , Serologic Tests/methods , Quality Control , Syphilis/diagnosis , Total Quality Management , Mass Screening/methods , Mass Screening/standards , Hepatitis B Surface Antigens/blood
6.
Sci Rep ; 14(1): 16683, 2024 07 19.
Article in English | MEDLINE | ID: mdl-39030224

ABSTRACT

When traditional statistical quality control protocols, represented by the Westgard protocol were applied to infectious disease serology, the rejection limits were questioned because of the high rejection probability. We first define the probability of false rejection (Pfr) and error detection (Ped) for infectious disease serology. QC data in 6 months were collected and the Pfr of each rule in the Westgard protocol and Rilibak protocol was evaluated. Then, as improvements, we chose different rules for negative and positive QC data to constitute an asymmetric protocol, furthermore, while reagent lot changes, the mean value of QC protocol is reset with the first 15 QC results of new lot reagent. QC materials and Standard Reference Materials were tested synchronously in the next 6 months, to verify whether the Pfr and Ped of the asymmetric protocol could meet the requirement. Protocol 1 exhibited the higher level of rejection rate among the two protocols, especially after reagent lot changes; Pfr below the lower control limit (LCL) was 1.39-21.78 times higher than the upper control limit (UCL); false rejections were more likely to occur in negative QC data, with Pfr-total of 27-65%. The asymmetric protocol can significantly reduce the proportion of analytes with Pfr by over 20%. Systematic error due to reagent lot changes and random error due to routine QC data variation were considered potential factors for excessive Pfr. Asymmetric QC protocol that can reduce Pfr by different control limits for negative and positive QC data.


Subject(s)
Communicable Diseases , Quality Control , Humans , Communicable Diseases/diagnosis , Communicable Diseases/immunology , Serologic Tests/methods , Serologic Tests/standards
7.
Viruses ; 16(6)2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38932207

ABSTRACT

The serological surveillance of bluetongue in bulk tank milk is an efficient and cost-effective method for the early detection of bluetongue virus incursions in unvaccinated free areas of the disease. In addition, the availability of standardized and reliable reagents and refined diagnostic procedures with high sensitivity and specificity are essential for surveillance purposes. However, no available reference materials for bluetongue virus serological surveillance in bulk tank milk exist. This study shows the production and characterization of reference material for the implementation of a commercially available bluetongue milk ELISA test in official laboratories, as well as the evaluation of a procedure to increase the sensitivity in samples with low levels of antibodies. This procedure, based on milk protein concentration, allowed us to notably increase the ELISA test's analytical sensitivity, which is useful for milk samples from farms with low within-herd prevalence or pools of bulk tank milk samples. The standardized milk reference material produced here, together with the evaluated procedure to improve analytical sensitivity, could be applied as tools to ensure an accurate diagnosis by official laboratories in bluetongue unvaccinated free areas.


Subject(s)
Bluetongue virus , Bluetongue , Enzyme-Linked Immunosorbent Assay , Milk Proteins , Milk , Sensitivity and Specificity , Animals , Milk/virology , Milk/chemistry , Bluetongue/diagnosis , Bluetongue/virology , Bluetongue virus/immunology , Bluetongue virus/isolation & purification , Enzyme-Linked Immunosorbent Assay/methods , Sheep , Cattle , Milk Proteins/analysis , Milk Proteins/immunology , Antibodies, Viral/blood , Serologic Tests/methods , Serologic Tests/standards , Reference Standards , Female
9.
Ann Biol Clin (Paris) ; 82(2): 215-224, 2024 06 05.
Article in French | MEDLINE | ID: mdl-38702909

ABSTRACT

The Westgard quality control (QC) rules are often applied in infectious diseases serology to validate the quality of results, but this requires a reasonable tradeoff between maximum sensitivity to errors and minimum false rejections. This article, in addition to illustrate the six sigma methodology in the QC management of the (anti-HCV Architect®) test, it discusses the main influencing factors on sigma value. Data from low positive and in-kit control materials spreading over 6 months and using four reagent kits, were used to calculate the precision of the test. The difference between the control material reactivity and the cut-off defined the error budget. Sigma values were > 6, which indicates that the method produces four erroneous results per million tests. The application of the six sigma concept made it possible to argue the choice of the new QC strategy (use of 13S rule with one positive control) and to relax the existing QC rules. This work provides a framework for infectious diseases serology laboratories to evaluate tests performances against a quality requirement and design an optimal QC strategy.


Subject(s)
Hepatitis C , Quality Control , Serologic Tests , Total Quality Management , Humans , Hepatitis C/blood , Hepatitis C/diagnosis , Total Quality Management/standards , Serologic Tests/standards , Serologic Tests/methods , Hepatitis C Antibodies/blood , Hepatitis C Antibodies/analysis , Hepacivirus/isolation & purification , Hepacivirus/immunology , Sensitivity and Specificity , Reagent Kits, Diagnostic/standards , Reproducibility of Results , Quality Assurance, Health Care/standards , Quality Assurance, Health Care/methods , Laboratories, Clinical/standards
10.
J Clin Microbiol ; 62(5): e0013924, 2024 May 08.
Article in English | MEDLINE | ID: mdl-38597655

ABSTRACT

We compared the performance of a new modified two-tier testing (MTTT) platform, the Diasorin Liaison chemiluminescent immunoassay (CLIA), to the Zeus enzyme-linked immunoassay (ELISA) MTTT and to Zeus ELISA/Viramed immunoblot standard two-tier testing (STTT) algorithm. Of 537 samples included in this study, 91 (16.9%) were positive or equivocal by one or more screening tests. Among these 91 samples, only 57 samples were concordant positive by first-tier screening tests, and only 19 of 57 were concordant by the three second-tier methods. For IgM results, positive percent agreement (PPA) was 68.1% for Diasorin versus 89.4% for Zeus compared to immunoblot. By contrast, the PPA for IgG for both Diasorin and Zeus was 100%. Using a 2-out-of-3 consensus reference standard, the PPAs for IgM were 75.6%, 97.8%, and 95.6% for Diasorin, Zeus, and immunoblot, respectively. The difference between Zeus MTTT and Diasorin MTTT for IgM detection was significant (P = 0.0094). PPA for both Diasorin and Zeus MTTT IgG assays was 100% but only 65.9% for immunoblot STTT (P = 0.0005). In total, second-tier positive IgM and/or IgG results were reported for 57 samples by Diasorin MTTT, 63 by Zeus MTTT, and 54 by Viramed STTT. While Diasorin CLIA MTTT had a much more rapid, automated, and efficient workflow, Diasorin MTTT was less sensitive for the detection of IgM than Zeus MTTT and STTT including in 5 early Lyme cases that were IgM negative but IgG positive. IMPORTANCE: The laboratory diagnosis of Lyme disease relies upon the detection of antibodies to Borrelia species. Standard two tier testing (STTT) methods rely upon immunoblots which have clinical and technical limitations. Modified two-tier testing (MTTT) methods have recently become available and are being widely adopted. There are limited independent data available assessing the performance of MTTT and STTT methods.


Subject(s)
Algorithms , Antibodies, Bacterial , Immunoglobulin G , Immunoglobulin M , Lyme Disease , Sensitivity and Specificity , Serologic Tests , Humans , Lyme Disease/diagnosis , Lyme Disease/immunology , Lyme Disease/blood , Immunoglobulin M/blood , Immunoglobulin G/blood , Serologic Tests/methods , Serologic Tests/standards , Antibodies, Bacterial/blood , Luminescent Measurements/methods , Immunoblotting/methods
11.
Diagn Microbiol Infect Dis ; 109(2): 116238, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38554539

ABSTRACT

The interpretation for Zika virus serology results is challenging due to high antibody cross reactivity with other flaviviruses. This limits availability of reliable and accurate methods for serosurveillance studies to understand the disease burden. Therefore, we conducted study to harmonize anti-Zika IgG antibody detection assays with 1st WHO International Standard (16/352) and working standard (16/320) for anti-Zika virus antibody.Additionally, evaluated NuGenTMZIKA-IgG and NovaLisa®ZIKA virus IgG-Capture ELISA using a panel of 278 seraFurther, 106 samples positive for other-flavi viruses were taken for assessing cross-reactivity of the assay, all serums were further tested by Zika-PRNT. The results of this study indicates satisfactory performance of both the assays. Serological and neutralization assays were calibrated according to the international standards. This will help in understanding antibody dynamics in serosurveillance and vaccine studies. However the performance of the kits with possibilities of cross-reactivity will have to be verified by coupling ZIKV and DENV specific ELISA.


Subject(s)
Antibodies, Viral , Cross Reactions , Enzyme-Linked Immunosorbent Assay , Immunoglobulin G , Zika Virus Infection , Zika Virus , Enzyme-Linked Immunosorbent Assay/methods , Enzyme-Linked Immunosorbent Assay/standards , Zika Virus/immunology , Immunoglobulin G/blood , Humans , Antibodies, Viral/blood , Zika Virus Infection/diagnosis , Zika Virus Infection/immunology , Zika Virus Infection/blood , Reagent Kits, Diagnostic/standards , Serologic Tests/standards , Serologic Tests/methods , Sensitivity and Specificity , Female , Adult , Adolescent , Young Adult
12.
Vet Parasitol ; 328: 110173, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38537410

ABSTRACT

Toxoplasma gondii is a paradigmatic zoonotic parasite from the One Health perspective, since it is broadly distributed and virtually infects all warm-blooded species. A wide variety of serological techniques have been developed to detect T. gondii infection in humans and animals. Our aim was to describe and compare the main characteristics of these serological tests and validation processes and to critically analyze whether these tests meet the standards required to ensure an accurate serological diagnosis. The current systematic review and meta-analysis included 134 studies that were published from 2013 to 2023. QUADAS 2 tool was used to evaluate the quality of the included studies. A total of 52 variables related to the characteristics of the techniques and analytical and diagnostic validation parameters were studied. A wider panel of tests was developed for humans, including techniques exclusively developed for humans that involve costly equipment and the measurement of different Ig isotypes that are considered biomarkers of congenital toxoplasmosis. Studies conducted in humans frequently employed commercial techniques as reference tests, measured different immunoglobulin isotypes with a predominance for IgG (>50%) and discriminated between acute and chronic infections. In animals, the most commonly used reference techniques were in-house tests, which almost exclusively detected IgG. Common limitations identified in a large number of studies were some misunderstandings of the terms "gold standard" and "reference test" and the absence of information about the negative and positive control sera used or the exact cutoff employed, which were independent of the quality of the study. There is a lack of analytical validation, with few evaluations of cross-reactivity with other pathogens. Diagnostic odds ratio values showed that indirect ELISA based on native or chimeric antigens performed better than other tests. The reproducibility of serological test results in both humans and animals is not guaranteed due to a lack of relevant information and analytical validation. Thus, several key issues should be considered in the future, including interlaboratory ring trials.


Subject(s)
Antibodies, Protozoan , Serologic Tests , Toxoplasma , Toxoplasmosis, Animal , Toxoplasmosis , Animals , Humans , Antibodies, Protozoan/blood , Reproducibility of Results , Serologic Tests/veterinary , Serologic Tests/standards , Serologic Tests/methods , Toxoplasma/immunology , Toxoplasmosis/diagnosis , Toxoplasmosis/immunology , Toxoplasmosis/blood , Toxoplasmosis, Animal/diagnosis , Toxoplasmosis, Animal/immunology , Toxoplasmosis, Animal/blood
13.
J Clin Microbiol ; 62(2): e0133923, 2024 Feb 14.
Article in English | MEDLINE | ID: mdl-38275299

ABSTRACT

Measles and rubella serological diagnoses are done by IgM detection. The World Health Organization Global Measles and Rubella Laboratory Network previously endorsed Siemens Enzygnost enzyme-linked immunosorbant assay kits, which have been discontinued. A recommended replacement has not been determined. We aimed to search for suitable replacements by conducting a systematic review and meta-analysis of IgM detection methods that are currently available for measles and rubella. A systematic literature search was performed in Medline, Embase, Global Health, Cochrane Central, and Scopus on March 22 and on 27 September 2023. Studies reporting measles and/or rubella IgM detection with terms around diagnostic accuracy were included. Risk of bias was assessed using QUADAS tools. Meta-DiSc and R were used for statistical analysis. Clinical samples totalling 5,579 from 28 index tests were included in the measles meta-analysis. Sensitivity and specificity of the individual measles studies ranged from 0.50 to 1.00 and 0.53 to 1.00, respectively. Pooled sensitivity and specificity of all measles IgM detection methods were 0.94 (CI: 0.90-0.97) and 0.94 (CI: 0.91-0.97), respectively. Clinical samples totalling 4,983 from 15 index tests were included in the rubella meta-analysis. Sensitivity and specificity of the individual rubella studies ranged from 0.78 to 1.00 and 0.52 to 1.00, respectively. Pooled sensitivity and specificity of all rubella IgM detection methods were 0.97 (CI: 0.93-0.98) and 0.96 (CI: 0.93-0.98), respectively. Although more studies would be ideal, our results may provide valuable information when selecting IgM detection methods for measles and/or rubella.


Subject(s)
Antibodies, Viral , Immunoglobulin M , Measles virus , Measles , Rubella virus , Rubella , Sensitivity and Specificity , Serologic Tests , Humans , Rubella/diagnosis , Measles/diagnosis , Rubella virus/immunology , Measles virus/immunology , Measles virus/isolation & purification , Immunoglobulin M/blood , Antibodies, Viral/blood , Serologic Tests/methods , Serologic Tests/standards , Reagent Kits, Diagnostic/standards
14.
Rev. bras. oftalmol ; 83: e0003, 2024. tab, graf
Article in Portuguese | LILACS | ID: biblio-1529931

ABSTRACT

RESUMO Objetivo: Identificar o perfil dos doadores de tecidos oculares humanos na área de atuação do Banco de Olhos da Paraíba, destacando o impacto da sorologia positiva para hepatite B no descarte dos tecidos para transplante. Métodos: O estudo é transversal e utilizou dados do Banco de Olhos da Paraíba entre janeiro de 2013 e dezembro de 2022. Dados sobre procedência, idade, sexo, causa do óbito, tempo entre óbito e enucleação, resultados sorológicos e motivo de descarte das córneas dos doadores foram coletados. Resultados: O maior motivo de descarte foi por sorologia positiva (56,5%), sendo positivadas as sorologias positivas para hepatite B e HBsAg em 11,1% e 4,75% dos pacientes, respectivamente. Conclusão: A sorologia positiva para hepatite B como um critério de descarte absoluto é responsável por grande parcela de descartes, apesar da pouca informação sobre suas repercussões e representação de infectividade nos receptores do transplante.


ABSTRACT Objective: To identify the profile of human ocular tissue donors in the area covered by the Eye Bank of Paraíba (PB), highlighting the impact of positive serology for hepatitis B (anti-HBc) in the disposal of tissues for transplantation. Methods: This is a cross-sectional that uses data from the Eye Bank of Paraíba (PB) between January 2013 and December 2022. Data on origin, age, sex, cause of death, time between death and enucleation, serological results, and reason for discarded donor corneas were collected. Results: The main reason for discarding was due to positive serology (56.5%), with positive anti-HBc and HBsAg serology in 11.1% and 4.75% of patients, respectively. Conclusion: Anti-HBc positive serology as an absolute disposal criterion is responsible for great part of disposals, despite little information about its repercussions and representation of infectivity in transplant recipients.


Subject(s)
Humans , Male , Female , Child, Preschool , Child , Adolescent , Adult , Middle Aged , Aged , Aged, 80 and over , Tissue Donors/statistics & numerical data , Corneal Transplantation/standards , Corneal Transplantation/statistics & numerical data , Donor Selection/standards , Eye Banks/standards , Hepatitis B Antibodies/analysis , Serologic Tests/standards , Hepatitis B virus , Cross-Sectional Studies , Retrospective Studies , Disease Transmission, Infectious/legislation & jurisprudence , Disease Transmission, Infectious/prevention & control , Disease Transmission, Infectious/statistics & numerical data , Eye Banks/statistics & numerical data , Hepatitis B/prevention & control , Hepatitis B/transmission , Hepatitis B Core Antigens/analysis
15.
J Clin Microbiol ; 61(6): e0011223, 2023 06 20.
Article in English | MEDLINE | ID: mdl-37222630

ABSTRACT

Treponema pallidum subsp. pallidum is a fastidious spirochete and the etiologic agent of syphilis, a sexually transmitted infection (STI). Syphilis diagnoses and disease staging are based on clinical findings and serologic testing. Moreover, according to most international guidelines, PCR analysis of swab samples from genital ulcers is included in the screening algorithm where possible. It has been suggested that PCR might be omitted from the screening algorithm due to low added value. As an alternative to PCR, IgM serology might be used. In this study, we wanted to establish the added value of PCR and IgM serology for diagnosing primary syphilis. Added value was defined as finding more cases of syphilis, preventing overtreatment, or limiting the extent of partner notification to more recent partners. We found that both PCR and IgM immunoblotting could aid the timely diagnosis of early syphilis in ~24% to 27% of patients. PCR has the greatest sensitivity and can be applied to cases with an ulcer with suspected reinfection or primary infection. In the absence of lesions, the IgM immunoblot could be used. However, the IgM immunoblot has better performance in cases with suspected primary infection than in reinfections. The target population, testing algorithm, time pressures, and costs should determine whether either test provides sufficient value to be implemented in clinical practice.


Subject(s)
Diagnostic Tests, Routine , Immunoglobulin M , Syphilis , Humans , Immunoblotting/standards , Immunoglobulin M/analysis , Polymerase Chain Reaction/standards , Syphilis/diagnosis , Syphilis/immunology , Syphilis/microbiology , Treponema pallidum/genetics , Serologic Tests/standards , Diagnostic Tests, Routine/economics , Diagnostic Tests, Routine/methods , Diagnostic Tests, Routine/standards , Sensitivity and Specificity
16.
Int J Mol Sci ; 23(6)2022 Mar 17.
Article in English | MEDLINE | ID: mdl-35328649

ABSTRACT

As the global SARS-CoV-2 pandemic continues to plague healthcare systems, it has become clear that opportunistic pathogens cause a considerable proportion of SARS-CoV-2-associated mortality and morbidity cases. Of these, Covid-Associated Pulmonary Aspergilliosis (CAPA) is a major concern with evidence that it occurs in the absence of traditional risk factors such as neutropenia and is diagnostically challenging for the attending physician. In this review, we focus on the immunopathology of SARS-CoV-2 and how this potentiates CAPA through dysregulation of local and systemic immunity as well as the unintended consequences of approved COVID treatments including corticosteroids and IL-6 inhibitors. Finally, we will consider how knowledge of the above may aid in the diagnosis of CAPA using current diagnostics and what treatment should be instituted in probable and confirmed cases.


Subject(s)
COVID-19/complications , COVID-19/immunology , Disease Susceptibility/immunology , Host-Pathogen Interactions/immunology , Pulmonary Aspergillosis/etiology , SARS-CoV-2/immunology , Antifungal Agents/therapeutic use , Biomarkers , COVID-19/virology , Disease Management , Humans , Immunocompromised Host , Pulmonary Aspergillosis/diagnosis , Pulmonary Aspergillosis/therapy , Reproducibility of Results , Serologic Tests/methods , Serologic Tests/standards , Treatment Outcome
17.
PLoS Negl Trop Dis ; 16(2): e0010152, 2022 02.
Article in English | MEDLINE | ID: mdl-35120141

ABSTRACT

BACKGROUND: Chikungunya virus (CHIKV) causes febrile illnesses and has always been misdiagnosed as other viral infections, such as dengue and Zika; thus, a laboratory test is needed. Serological tests are commonly used to diagnose CHIKV infection, but their accuracy is questionable due to varying degrees of reported sensitivities and specificities. Herein, we conducted a systematic review and meta-analysis to evaluate the diagnostic accuracy of serological tests currently available for CHIKV. METHODOLOGY AND PRINCIPAL FINDINGS: A literature search was performed in PubMed, CINAHL Complete, and Scopus databases from the 1st December 2020 until 22nd April 2021. Studies reporting sensitivity and specificity of serological tests against CHIKV that used whole blood, serum, or plasma were included. QUADAS-2 tool was used to assess the risk of bias and applicability, while R software was used for statistical analyses. Thirty-five studies were included in this meta-analysis; 72 index test data were extracted and analysed. Rapid and ELISA-based antigen tests had a pooled sensitivity of 85.8% and 82.2%, respectively, and a pooled specificity of 96.1% and 96.0%, respectively. According to our meta-analysis, antigen detection tests serve as a good diagnostic test for acute-phase samples. The IgM detection tests had more than 90% diagnostic accuracy for ELISA-based tests, immunofluorescence assays, in-house developed tests, and samples collected after seven days of symptom onset. Conversely, low sensitivity was found for the IgM rapid test (42.3%), commercial test (78.6%), and for samples collected less than seven of symptom onset (26.2%). Although IgM antibodies start to develop on day 2 of CHIKV infection, our meta-analysis revealed that the IgM detection test is not recommended for acute-phase samples. The diagnostic performance of the IgG detection tests was more than 93% regardless of the test formats and whether the test was commercially available or developed in-house. The use of samples collected after seven days of symptom onset for the IgG detection test suggests that IgG antibodies can be detected in the convalescent-phase samples. Additionally, we evaluated commercial IgM and IgG tests for CHIKV and found that ELISA-based and IFA commercial tests manufactured by Euroimmun (Lübeck, Germany), Abcam (Cambridge, UK), and Inbios (Seattle, WA) had diagnostic accuracy of above 90%, which was similar to the manufacturers' claim. CONCLUSION: Based on our meta-analysis, antigen or antibody-based serological tests can be used to diagnose CHIKV reliably, depending on the time of sample collection. The antigen detection tests serve as a good diagnostic test for samples collected during the acute phase (≤7 days post symptom onset) of CHIKV infection. Likewise, IgM and IgG detection tests can be used for samples collected in the convalescent phase (>7 days post symptom onset). In correlation to the clinical presentation of the patients, the combination of the IgM and IgG tests can differentiate recent and past infections.


Subject(s)
Antigens, Viral/isolation & purification , Chikungunya Fever/diagnosis , Serologic Tests/standards , Antigens, Viral/blood , Chikungunya virus/immunology , Chikungunya virus/isolation & purification , Humans , Immunoglobulin G/blood , Immunoglobulin M/blood , Sensitivity and Specificity
18.
Clin Transl Med ; 11(12): e668, 2021 12.
Article in English | MEDLINE | ID: mdl-34898055

ABSTRACT

The level of postvaccine protection depends on two factors: antibodies and T-cell responses. While the first one is relatively easily measured, the measuring of the second one is a difficult problem. The recent studies indicate that the first one may be a good proxy for the protection, at least for SARS-CoV-2. The massive data currently gathered by both researcher and citizen scientists may be pivotal in confirming this observation, and the collective body of evidence is growing daily. This leads to an acceptance of IgG antibody levels as an accessible biomarker of individual's protection. With enormous and immediate need for assessing patient condition at the point of care, quantitative antibody analysis remains the most effective and efficient way to assess the protection against the disease. Let us not discount importance of reference points in the turmoil of current pandemics.


Subject(s)
Antibodies, Viral/chemistry , Antibodies/chemistry , Biomarkers/metabolism , COVID-19/blood , COVID-19/immunology , Antibody Specificity , Humans , Immune System , Immunity , Immunoglobulin G/metabolism , Intensive Care Units , Pandemics , Point-of-Care Systems , SARS-CoV-2 , Serologic Tests/methods , Serologic Tests/standards , Vaccines
19.
Viruses ; 13(9)2021 08 30.
Article in English | MEDLINE | ID: mdl-34578299

ABSTRACT

Phleboviruses (genus Phlebovirus, family Phenuiviridae) are emerging pathogens of humans and animals. Sand-fly-transmitted phleboviruses are found in Europe, Africa, the Middle East, and the Americas, and are responsible for febrile illness and nervous system infections in humans. Rio Grande virus (RGV) is the only reported phlebovirus in the United States. Isolated in Texas from southern plains woodrats, RGV is not known to be pathogenic to humans or domestic animals, but serologic evidence suggests that sheep (Ovis aries) and horses (Equus caballus) in this region have been infected. Rift Valley fever virus (RVFV), a phlebovirus of Africa, is an important pathogen of wild and domestic ruminants, and can also infect humans with the potential to cause severe disease. The introduction of RVFV into North America could greatly impact U.S. livestock and human health, and the development of vaccines and countermeasures is a focus of both the CDC and USDA. We investigated the potential for serologic reagents used in RVFV diagnostic assays to also detect cells infected with RGV. Western blots and immunocytochemistry assays were used to compare the antibody detection of RGV, RVFV, and two other New World phlebovirus, Punta Toro virus (South and Central America) and Anhanga virus (Brazil). Antigenic cross-reactions were found using published RVFV diagnostic reagents. These findings will help to inform test interpretation to avoid false positive RVFV diagnoses that could lead to public health concerns and economically costly agriculture regulatory responses, including quarantine and trade restrictions.


Subject(s)
Cross Reactions/immunology , Phlebovirus/immunology , Reagent Kits, Diagnostic/standards , Rift Valley fever virus/immunology , Serologic Tests/standards , Animals , Bunyaviridae Infections/classification , Bunyaviridae Infections/diagnosis , Bunyaviridae Infections/immunology , Horses/virology , Phlebovirus/classification , Phlebovirus/pathogenicity , Rift Valley Fever/diagnosis , Rift Valley Fever/immunology , Rift Valley fever virus/pathogenicity , Serologic Tests/methods , Sheep/virology , United States
20.
Int J Technol Assess Health Care ; 37(1): e87, 2021 Sep 22.
Article in English | MEDLINE | ID: mdl-34548114

ABSTRACT

OBJECTIVE: In vitro diagnostic tests for SARS-COV-2, also known as serological tests, have rapidly spread. However, to date, mostly single-center technical and diagnostic performance's assessments have been carried out without an intralaboratory validation process and a health technology assessment (HTA) systematic approach. Therefore, the rapid HTA for evaluating antibody tests for SARS-COV-2 was applied. METHODS: The use of rapid HTA is an opportunity to test innovative technology. Unlike traditional HTA (which evaluates the benefits of new technologies after being tested in clinical trials or have been applied in practice for some time), the rapid HTA is performed during the early stages of developing new technology. A multidisciplinary team conducted the rapid HTA following the HTA Core Model® (version 3.0) developed by the European Network for Health Technology Assessment. RESULTS: The three methodological and analytical steps used in the HTA applied to the evaluation of antibody tests for SARS-COV-2 are reported: the selection of the tests to be evaluated; the research and collection of information to support the adoption and appropriateness of the technology; and the preparation of the final reports and their dissemination. Finally, the rapid HTA of serological tests for SARS-CoV-2 is summarized in a report that allows its dissemination and communication. CONCLUSIONS: The rapid-HTA evaluation method, in addition to highlighting the characteristics that differentiate the tests from each other, guarantees a timely and appropriate evaluation, becoming a tool to create a direct link between science and health management.


Subject(s)
COVID-19 Testing/methods , COVID-19/diagnosis , COVID-19/immunology , Serologic Tests/methods , Humans , SARS-CoV-2 , Serologic Tests/standards , Technology Assessment, Biomedical , Time Factors
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