ABSTRACT
Point-of-care serological and direct antigen testing offers actionable insights for diagnosing challenging illnesses, empowering distributed health systems. Here, we report a POC-compatible serologic test for Lyme disease (LD), leveraging synthetic peptides specific to LD antibodies and a paper-based platform for rapid, and cost-effective diagnosis. Antigenic epitopes conserved across Borrelia burgdorferi genospecies, targeted by IgG and IgM antibodies, are selected to develop a multiplexed panel for detection of LD antibodies from patient sera. Multiple peptide epitopes, when combined synergistically with a machine learning-based diagnostic model achieve high sensitivity without sacrificing specificity. Blinded validation with 15 LD-positive and 15 negative samples shows 95.5% sensitivity and 100% specificity. Blind testing with the CDC's LD repository samples confirms the test accuracy, matching lab-based two-tier results, correctly differentiating between LD and look-alike diseases. This LD diagnostic test could potentially replace the cumbersome two-tier testing, improving diagnosis and enabling earlier treatment while facilitating immune monitoring and surveillance.
Subject(s)
Antibodies, Bacterial , Borrelia burgdorferi , Immunoglobulin G , Immunoglobulin M , Lyme Disease , Sensitivity and Specificity , Serologic Tests , Lyme Disease/diagnosis , Lyme Disease/immunology , Lyme Disease/blood , Lyme Disease/microbiology , Humans , Serologic Tests/methods , Borrelia burgdorferi/immunology , Antibodies, Bacterial/blood , Antibodies, Bacterial/immunology , Immunoglobulin M/blood , Immunoglobulin M/immunology , Immunoglobulin G/blood , Immunoglobulin G/immunology , Antigens, Bacterial/immunology , Machine Learning , Epitopes/immunology , Point-of-Care Testing , Point-of-Care SystemsABSTRACT
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/bloodABSTRACT
Enzyme-linked immunosorbent assays (ELISA) are currently the method of choice for the serodiagnosis of pertussis and play a key role in the diagnosis of pertussis in adolescents and adults, as well as in epidemiological studies. In the present study, the in-house developed indirect ELISA was comparatively evaluated with six commercial kits from various manufacturers. Antipertussis antibodies were measured in 40 serum samples from patients with clinical symptoms of respiratory tract infection, in two WHO standards, and in seven human ECDC control sera. IgA and IgG antibodies were detected at a diagnostically significant level by different ELISA kits of 5.0% to 27.0% and 12.0% to 70.0% of patients' sera, appropriately. The analysis of results carried out with six commercial kits showed only 17.5% consistent results in class IgG (either clearly positive or negative). The average percentage of errors in the level of antibodies determined in the control samples, reference serum samples, differed quite significantly and ranged from 9.5% to 35.4% depending on the kit. This poor correlation of the results obtained on various serological tests intended for the serodiagnosis of pertussis may cause very serious diagnostic problems, especially when examining a serum sample obtained once during the course of the disease.
Subject(s)
Antibodies, Bacterial , Bordetella pertussis , Enzyme-Linked Immunosorbent Assay , Immunoglobulin A , Immunoglobulin G , Whooping Cough , Humans , Enzyme-Linked Immunosorbent Assay/methods , Bordetella pertussis/immunology , Antibodies, Bacterial/blood , Whooping Cough/diagnosis , Whooping Cough/immunology , Whooping Cough/blood , Immunoglobulin G/blood , Adolescent , Immunoglobulin A/blood , Adult , Child , Sensitivity and Specificity , Serologic Tests/methods , Reagent Kits, Diagnostic/standards , Child, Preschool , Young Adult , Female , MaleABSTRACT
BACKGROUND: Modified 2-tiered testing (MTTT) for Lyme disease utilizes automatable, high throughput immunoassays (AHTIs) in both tiers without involving western immunoblots, offering performance and practical advantages over standard 2-tiered testing (STTT; first-tier AHTI followed by immunoglobulin M (IgM) and immunoglobulin G (IgG) western immunoblots). For MTTT, Centers for Disease Control and Prevention recommends using AHTI test kits that have been cleared by Food and Drug Administration (FDA) specifically for this intended use. We evaluated performance of FDA-cleared MTTT commercial test kits from 3 manufacturers by comparing with STTT results. METHODS: We performed MTTT (total antibody AHTI with reflex to separate IgM and IgG AHTIs) using test kits from Diasorin, Gold Standard Diagnostics (GSD), and Zeus Scientific on 382 excess serum samples submitted to the clinical laboratory for routine Lyme disease serologic testing in July 2018, measuring agreement between MTTT and STTT using the κ statistic. RESULTS: Overall agreement with STTT was 0.87 (95% confidence interval [CI], .77-.97) using Diasorin assays (almost perfect agreement), 0.80 (95% CI, .68-.93) using GSD assays (substantial agreement) and 0.79 (95% CI, .68-.90) using Zeus assays (substantial agreement). For detection of IgM reactivity, agreement between MTTT and STTT was 0.70 (.51-.90; substantial), 0.63 (95% CI, .44-.82; substantial) and 0.56 (95% CI, .38-.73; moderate), respectively. For detection of IgG reactivity, MTTT/STTT agreement was 0.73 (95% CI,.58-.88), 0.78 (95% CI, .62-.94), and 0.75 (95% CI, .60-.90), respectively (substantial agreement in all cases). CONCLUSIONS: MTTT results obtained using commercial test kits from 3 different manufacturers had substantial to almost perfect agreement with STTT results overall and moderate to substantial agreement for IgM and IgG detection independently. Commercial MTTT tests can be used broadly for the diagnosis of Lyme disease.
Subject(s)
Antibodies, Bacterial , Immunoglobulin G , Immunoglobulin M , Lyme Disease , Reagent Kits, Diagnostic , Serologic Tests , Lyme Disease/diagnosis , Lyme Disease/immunology , Lyme Disease/blood , Humans , Serologic Tests/methods , Immunoglobulin G/blood , Immunoglobulin M/blood , Reagent Kits, Diagnostic/standards , Antibodies, Bacterial/blood , Algorithms , Sensitivity and Specificity , Immunoassay/methods , United States , Borrelia burgdorferi/immunology , Middle Aged , Adult , FemaleABSTRACT
The rational laboratory use and implementation of test ordering procedures aim to reduce unnecessary test requests. This study aimed to determine the financial burden caused by inappropriate serological test requests for viral hepatitis and to investigate physicians' reasons for making unnecessary test requests. We performed a retrospective evaluation of inappropriate requests for hepatitis serology testing and the financial burden they caused at a tertiary care hospital over a 1-year period. The study found 2183 (3.84%) inappropriate test requests, costing $3309.00. Of these, 357 were same-day repeat requests and 1826 were requests not following diagnostic algorithms. In the logistic regression analysis of the factors affecting unnecessary test requests, a statistically significant difference was found between whether the unit was internal or surgical, whether the request came from inpatient services or outpatient clinics, and the professional titles (Pâ <â .05). Both types of inappropriate requests were more common among male physicians (Pâ <â .05). The highest rates of inappropriate test requesting were in physical therapy and rehabilitation, pediatrics, and adult emergency units. To identify the reasons behind unnecessary test requests, 135 physicians from 23 different departments participated in the survey. The main reasons for requesting tests were identified as protecting against malpractice and fears of misdiagnosis or overlooking a diagnosis. It has been observed that physicians often order tests routinely, without being fully familiar with standard test ordering procedures based on diagnostic algorithms, and lacking knowledge about rational laboratory use. The cost of tests is mostly unknown to clinicians. The study concludes that there are laboratory tests that incur much higher costs. When this assessment is applied to the entire laboratory, it becomes clear how significant a financial burden, unnecessary workload, and loss of time this situation can cause. Identifying the presence of unnecessary test requests is the first step in preventing them. Appropriate measures include highlighting these issues, providing necessary information, and offering in-service training.
Subject(s)
Unnecessary Procedures , Humans , Retrospective Studies , Male , Female , Unnecessary Procedures/economics , Unnecessary Procedures/statistics & numerical data , Serologic Tests/economics , Serologic Tests/statistics & numerical data , Hepatitis, Viral, Human/diagnosis , Hepatitis, Viral, Human/economics , Adult , Practice Patterns, Physicians'/statistics & numerical data , Practice Patterns, Physicians'/economics , Tertiary Care Centers , Middle AgedABSTRACT
BACKGROUND: Chagas disease (CD), a neglected parasitic disease caused by Trypanosoma cruzi, poses a significant health threat in Latin America and has emerged globally because of human migration. Trypanosoma cruzi infects humans and over 100 other mammalian species, including dogs, which are important sentinels for assessing the risk of human infection. Nonetheless, the serodiagnosis of T. cruzi in dogs is still impaired by the absence of commercial tests. In this study, we investigated the diagnostic accuracy of four chimeric recombinant T. cruzi IBMP antigens (IBMP-8.1, IBMP-8.2, IBMP-8.3, and IBMP-8.4) for detecting anti-T. cruzi antibodies in dogs, using latent class analysis (LCA). METHODS: We examined 663 canine serum samples, employing indirect ELISA with the chimeric antigens. LCA was utilized to establish a latent variable as a gold standard for T. cruzi infection, revealing distinct response patterns for each antigen. RESULTS: The IBMP (Portuguese acronym for the Molecular Biology Institute of Paraná) antigens achieved area under the ROC curve (AUC) values ranging from 90.9% to 97.3%. The highest sensitivity was attributed to IBMP-8.2 (89.8%), while IBMP-8.1, IBMP-8.3, and IBMP-8.4 achieved 73.5%, 79.6%, and 85.7%, respectively. The highest specificity was observed for IBMP-8.4 (98.6%), followed by IBMP-8.2, IBMP-8.3, and IBMP-8.1 with specificities of 98.3%, 94.4%, and 92.7%, respectively. Predictive values varied according to prevalence, indicating higher effectiveness in endemic settings. CONCLUSIONS: Our findings underscore the remarkable diagnostic performance of IBMP-8.2 and IBMP-8.4 for the serodiagnosis of Trypanosoma cruzi in dogs, representing a promising tool for the diagnosis of CD in dogs. These chimeric recombinant antigens may not only enhance CD surveillance strategies but also hold broader implications for public health, contributing to the global fight against this neglected tropical disease.
Subject(s)
Antibodies, Protozoan , Antigens, Protozoan , Chagas Disease , Dog Diseases , Enzyme-Linked Immunosorbent Assay , Sensitivity and Specificity , Serologic Tests , Trypanosoma cruzi , Animals , Dogs , Chagas Disease/diagnosis , Chagas Disease/veterinary , Chagas Disease/parasitology , Trypanosoma cruzi/immunology , Trypanosoma cruzi/genetics , Dog Diseases/diagnosis , Dog Diseases/parasitology , Antigens, Protozoan/immunology , Antigens, Protozoan/genetics , Serologic Tests/methods , Serologic Tests/veterinary , Enzyme-Linked Immunosorbent Assay/methods , Enzyme-Linked Immunosorbent Assay/veterinary , Antibodies, Protozoan/blood , Recombinant Proteins/immunology , Recombinant Proteins/geneticsABSTRACT
BACKGROUND: Strongyloidiasis is caused by a neglected nematode, manifesting as chronic intestinal infection with potentially severe manifestations. The disease is an emerging problem in non-endemic countries affecting travelers and migrants. Diagnosis of strongyloidiasis is hampered by the lack of standardization and absence of a gold standard. Since adequate direct methods to detect the motile larvae in stool samples are not widely available, other techniques such as serology have been developed. METHODS: We evaluated three commercial ELISA kits (DRG Instruments, IVD Research, and Bordier Affinity Products) to detect IgG antibodies against Strongyloides stercoralis assays utilizing serum samples from travelers with microscopically confirmed strongyloidiasis (n = 50) and other imported helminthic infections (n = 159) as well as healthy controls (n = 50). RESULTS: The DRG, IVD, and Bordier assays showed sensitivities of 58.0%, 64.0%, and 56.0%, respectively. Specificity values were 96.0%, 96.0%, and 92.0% in healthy controls, and 67.3%, 62.9%, and 76.7% in cases with other helminth infections, respectively. Cross-reactions were mostly observed in cases with other nematodes (37.5%, 42.5%, and 20.0%, respectively), but also in trematode (33.3%, 38.1%, and 19.0%, respectively) and in cestode infections (25.0%, 30.0%, and 32.5%, respectively). CONCLUSION: The study demonstrates the diagnostic limitations of serological assays to detect or exclude cases of strongyloidiasis in returning travelers, who frequently present with recent or acute infections.
Subject(s)
Antibodies, Helminth , Enzyme-Linked Immunosorbent Assay , Immunoglobulin G , Sensitivity and Specificity , Serologic Tests , Strongyloides stercoralis , Strongyloidiasis , Strongyloidiasis/diagnosis , Strongyloidiasis/immunology , Humans , Animals , Strongyloides stercoralis/immunology , Strongyloides stercoralis/isolation & purification , Antibodies, Helminth/blood , Enzyme-Linked Immunosorbent Assay/methods , Immunoglobulin G/blood , Serologic Tests/methods , Male , Adult , Female , Middle Aged , Reagent Kits, Diagnostic/standards , Cross ReactionsABSTRACT
OBJECTIVE: To develop a machine learning diagnostic model based on MMP7 and other serological testing indicators for early and efficient diagnosis of biliary atresia (BA). METHODS: A retrospective analysis was conducted on patient information from those hospitalized for pathological jaundice at Beijing Children's Hospital between January 1, 2019, and December 31, 2023. Patients with serum MMP7, liver stiffness measurements, and other routine serological tests were included in the study. Six machine learning models were constructed, including logistic regression (LR), random forest (RF), decision tree (DET), support vector machine classifier (SVC), neural network (MLP), and extreme gradient boosting (XGBoost), to diagnose BA. The area under the receiver operating characteristic curve was used to evaluate the diagnostic efficacy of the various models. RESULTS: A total of 98 patients were included in the study, comprising 64 BA patients and 34 patients with other cholestatic liver diseases. Among the six machine learning models, the XGBoost algorithm model and RF algorithm model achieved the best predictive performance, with an AUROC of nearly 100% in both the training and validation sets. In the training set, these two algorithm models achieved an accuracy, precision, recall, F1 score, and AUROC of 1. Through model interpretation analysis, serum MMP7 levels, serum GGT levels, and acholic stools were identified as the most important indicators for diagnosing BA. The nomogram constructed based on the XGBoost algorithm model also demonstrated convenient and efficient diagnostic efficacy. CONCLUSION: Machine learning models, especially the XGBoost algorithm and RF algorithm models, constructed based on preoperative serum MMP7 and serological tests can diagnose BA more efficiently and accurately. The most important influencing factors for diagnosis are serum MMP7, serum GGT, and acholic stools.
Subject(s)
Biliary Atresia , Machine Learning , Matrix Metalloproteinase 7 , Humans , Biliary Atresia/diagnosis , Biliary Atresia/blood , Retrospective Studies , Male , Female , Infant , Matrix Metalloproteinase 7/blood , Serologic Tests/methods , ROC Curve , Biomarkers/blood , Child, PreschoolABSTRACT
BACKGROUND: Since Imbach [1] first reported the use of high-dose intravenous immunoglobulin (IVIg) in the treatment of idiopathic thrombocytopenic purpura (ITP) in children, indications for IVIg therapy have been increaseing. At present, IVIg infusion has become an important means of clinical treatment. The phenomenon of anti-HBs and anti-HBc elevation caused by IVIg infusion in patients has been reported in journals, but similar reports in journals related to laboratory diagnosis are rare. METHODS: We reported a case of a patient with immune thrombocytopenia (ITP) which interfered with hepatitis B virus (HBV) serological detection after receiving intravenous IVIg. We used chemiluminescence immunoassay to detect serological markers of HBV. IU/mL was used to represent the detection data of HBsAg and HBsAb and cutoff value was used to represent the detection HBeAg, HBeAb, and HbcAb. RESULTS: The serological markers of HBV were all negative before IVIg infusion. One week after IVIG infusion, the item was tested again, and the results of HBsAb, HBeAb, and HBcAb were positive. As the time increased after infusion, HBsAb, HBeAb, and HBcAb in the patient gradually decreased. CONCLUSIONS: After IVIg infusion, the sudden positive change of HBsAb, HBeAb, and HbcAb in the patient's body was not caused by HBV infection, but caused by the infusion of foreign antibody. This case study shows that physicians should be particularly careful when interpreting results in patients treated with intravenous IVIg involving viral hepatitis B.
Subject(s)
Hepatitis B Antibodies , Hepatitis B virus , Hepatitis B , Immunoglobulins, Intravenous , Purpura, Thrombocytopenic, Idiopathic , Humans , Immunoglobulins, Intravenous/therapeutic use , Immunoglobulins, Intravenous/administration & dosage , Purpura, Thrombocytopenic, Idiopathic/diagnosis , Purpura, Thrombocytopenic, Idiopathic/drug therapy , Purpura, Thrombocytopenic, Idiopathic/blood , Purpura, Thrombocytopenic, Idiopathic/immunology , Hepatitis B/diagnosis , Hepatitis B/immunology , Hepatitis B/blood , Hepatitis B Antibodies/blood , Hepatitis B virus/immunology , Hepatitis B Surface Antigens/blood , Hepatitis B Surface Antigens/immunology , Serologic Tests/methods , Male , FemaleABSTRACT
BACKGROUND: Serological screening tests play a crucial role to diagnose gambiense human African trypanosomiasis (gHAT). Presently, they preselect individuals for microscopic confirmation, but in future "screen and treat" strategies they will identify individuals for treatment. Variability in reported specificities, the development of new rapid diagnostic tests (RDT) and the hypothesis that malaria infection may decrease RDT specificity led us to evaluate the specificity of 5 gHAT screening tests. METHODS: During active screening, venous blood samples from 1095 individuals from Côte d'Ivoire and Guinea were tested consecutively with commercial (CATT, HAT Sero-K-SeT, Abbott Bioline HAT 2.0) and prototype (DCN HAT RDT, HAT Sero-K-SeT 2.0) gHAT screening tests and with a malaria RDT. Individuals with ≥ 1 positive gHAT screening test underwent microscopy and further immunological (trypanolysis with T.b. gambiense LiTat 1.3, 1.5 and 1.6; indirect ELISA/T.b. gambiense; T.b. gambiense inhibition ELISA with T.b. gambiense LiTat 1.3 and 1.5 VSG) and molecular reference laboratory tests (PCR TBRN3, 18S and TgsGP; SHERLOCK 18S Tids, 7SL Zoon, and TgsGP; Trypanozoon S2-RT-qPCR 18S2, 177T, GPI-PLC and TgsGP in multiplex; RT-qPCR DT8, DT9 and TgsGP in multiplex). Microscopic trypanosome detection confirmed gHAT, while other individuals were considered gHAT free. Differences in fractions between groups were assessed by Chi square and differences in specificity between 2 tests on the same individuals by McNemar. RESULTS: One gHAT case was diagnosed. Overall test specificities (n = 1094) were: CATT 98.9% (95% CI: 98.1-99.4%); HAT Sero-K-SeT 86.7% (95% CI: 84.5-88.5%); Bioline HAT 2.0 82.1% (95% CI: 79.7-84.2%); DCN HAT RDT 78.2% (95% CI: 75.7-80.6%); and HAT Sero-K-SeT 2.0 78.4% (95% CI: 75.9-80.8%). In malaria positives, gHAT screening tests appeared less specific, but the difference was significant only in Guinea for Abbott Bioline HAT 2.0 (P = 0.03) and HAT Sero-K-Set 2.0 (P = 0.0006). The specificities of immunological and molecular laboratory tests in gHAT seropositives were 98.7-100% (n = 399) and 93.0-100% (n = 302), respectively. Among 44 reference laboratory test positives, only the confirmed gHAT patient and one screening test seropositive combined immunological and molecular reference laboratory test positivity. CONCLUSIONS: Although a minor effect of malaria cannot be excluded, gHAT RDT specificities are far below the 95% minimal specificity stipulated by the WHO target product profile for a simple diagnostic tool to identify individuals eligible for treatment. Unless specificity is improved, an RDT-based "screen and treat" strategy would result in massive overtreatment. In view of their inconsistent results, additional comparative evaluations of the diagnostic performance of reference laboratory tests are indicated for better identifying, among screening test positives, those at increased suspicion for gHAT. TRIAL REGISTRATION: The trial was retrospectively registered under NCT05466630 in clinicaltrials.gov on July 15 2022.
Subject(s)
Sensitivity and Specificity , Trypanosoma brucei gambiense , Trypanosomiasis, African , Humans , Trypanosomiasis, African/diagnosis , Trypanosomiasis, African/blood , Cote d'Ivoire , Trypanosoma brucei gambiense/immunology , Trypanosoma brucei gambiense/isolation & purification , Adult , Guinea , Prospective Studies , Male , Adolescent , Female , Young Adult , Middle Aged , Serologic Tests/methods , Child , Enzyme-Linked Immunosorbent Assay/methods , Aged , Child, Preschool , Antibodies, Protozoan/bloodABSTRACT
Human cysticercosis caused by Taenia soliun (T. soliun) is endemic in certain areas of Latin America, Asia and Sub-Saharan Africa. Neurocysticercosis (NCC) is mainly diagnosed by neuroimaging, which, in most cases, is unavailable in endemic areas. Due to their high sensitivity and specificity, serological tests such as enzyme-linked immunosorbent assay (ELISA) and Western blot (WB) based on the glycosylated fraction of the cyst CS50 are widely used for the detection of the anti-cysticercus IgG antibodies despite their significant cost and the need of cysticercus material. Given their cost-effectivess and simplicity, immunoassays based on recombinant proteins could provide new alternatives for human cysticercosis diagnosis: such tests would be aimed at screening those people living in remote areas who need further examination. To date, however, no test using recombinant antigens is commercially available. Herein, five recombinant proteins (R14, R18, R93.1, R914.1, and R915.2) were produced, three of which (R93.1, R914.1, and R915.2) were newly identified from the cyst fluid. Evaluation of the diagnostic performance of these recombinant antigens by ELISA was done using sera from 200 epileptic and non-epileptic individuals in comparison with the WB-CS50 as the reference serological method. Recombinant proteins-based ELISA showed a level of diagnostic performance that is inferior than the reference serological method, but similar to that of the native antigen ELISA for human cysticercosis (commonly used for screening). Further optimization of expression conditions is still needed in order to improve proteins solubility and enhance diagnostic performance for human cysticercosis detection. However, this preliminary evaluation of the recombinant antigens has shown their potential valuable use for screening cysticercosis in patients with epilepsy attending dispensaries in remote areas. Future studies should be conducted to evaluate our recombinant antigens in a large group of patients with different stages of NCC, and in correlation with imaging findings.
Subject(s)
Antibodies, Helminth , Antigens, Helminth , Blotting, Western , Cysticercosis , Enzyme-Linked Immunosorbent Assay , Recombinant Proteins , Sensitivity and Specificity , Taenia solium , Humans , Recombinant Proteins/immunology , Antigens, Helminth/immunology , Antigens, Helminth/genetics , Cysticercosis/diagnosis , Animals , Taenia solium/immunology , Taenia solium/genetics , Antibodies, Helminth/blood , Immunoglobulin G/blood , Neurocysticercosis/diagnosis , Neurocysticercosis/immunology , Epilepsy/diagnosis , Adult , Male , Serologic Tests/methods , FemaleABSTRACT
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/bloodABSTRACT
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 , BrazilABSTRACT
BACKGROUND: Brucellosis is a zoonosis endemic to specific geographical regions. In first line laboratories, diagnosis is made by blood culture or Rose Bengal (RB) serology. METHODS: We compare brucellosis testing between 2012-2021 at two university hospitals in Brussels, Belgium with concomitant national confirmed cases and institutional cases. RESULTS: RB testing increased from 30 to 211 tests/year between 2012-2021. A total of fifty-two national brucellosis cases were notified during the study period, of which fifteen cases in Brussels. No trend was noted nationally or regionally. Epidemiological data indicated travel to endemic regions, confirmed by strain testing. Institutional cases all showed symptomatic presentations with positive travel histories. CONCLUSIONS: Serologic testing inappropriately increases yearly, while annual imported brucellosis cases remain rare, and have positive travel histories and are symptomatic. We therefore support current recommendations of limiting RB testing to symptomatic patients at risk of exposure, meaning predominantly positive recent travel history.
Subject(s)
Brucellosis , Rose Bengal , Serologic Tests , Brucellosis/diagnosis , Brucellosis/epidemiology , Humans , Male , Female , Belgium/epidemiology , Adult , Middle Aged , Aged , Travel , Young Adult , Brucella/immunology , Brucella/isolation & purification , Hospitals, University/statistics & numerical dataABSTRACT
A simple IgG-speciï¬c ELISA for Leptospira spp. was compared with the microscopic agglutination test (MAT) to detect IgG antibody responses to a commercial vaccine in cattle. We used an enzyme-linked immunosorbent assay (ELISA) with sonicated Leptospira interrogans serovar copenhageni M 20. After initial vaccination, specific antibodies against Leptospira spp. were detected in 90â¯% of the animals by IgG-ELISA and 60â¯% by MAT, while after booster, antibodies were detected in 100â¯% and 80â¯% of the animals by IgG-ELISA and MAT, respectively. Both serological MAT and ELISA tests revealed interferences of vaccine antibodies. Disease diagnosis with ELISA and MAT methods should be made two and a half months and four months, respectively, after vaccination to avoid interference of vaccine antibodies. On the other hand, our results suggest that IgG-ELISA may be a useful method to assess the development of IgG antibodies induced by Leptospira vaccine.
Subject(s)
Agglutination Tests , Antibodies, Bacterial , Bacterial Vaccines , Cattle Diseases , Enzyme-Linked Immunosorbent Assay , Immunoglobulin G , Leptospirosis , Animals , Leptospirosis/veterinary , Leptospirosis/diagnosis , Leptospirosis/immunology , Cattle , Cattle Diseases/microbiology , Cattle Diseases/diagnosis , Cattle Diseases/immunology , Cattle Diseases/blood , Enzyme-Linked Immunosorbent Assay/veterinary , Antibodies, Bacterial/blood , Bacterial Vaccines/immunology , Immunoglobulin G/blood , Agglutination Tests/veterinary , Leptospira interrogans/immunology , Leptospira/immunology , Vaccination/veterinary , Serologic Tests/veterinaryABSTRACT
Surveillance and sustained control of visceral leishmaniasis (VL) require reliable serodiagnostic tools. rK39, the gold standard antigen for VL diagnosis, is limited by its documented poor sensitivity in certain endemic regions, such as East Africa, and by the longevity of its antibodies, making it difficult to distinguish active from cured infections. In a recent publication in mBio, Roberts et al. (A. J. Roberts, H.B. Ong, S. Clare, C. Brandt, et al., mBio 15:e00859-24, 2024, https://doi.org/10.1128/mbio.00859-24) identified new immunogenic Leishmania candidates in dogs and humans. In dogs, combined antigens LdBPK_290790.1 + LdBPK_362700.1 (D4 +D46) distinguished symptomatic from asymptomatic infections. For humans, LdBPK_323600.1 (D36) antigen produced short-lived antibodies and performed well in patient cohorts from Bangladesh and Ethiopia, but not Kenya. This study adds promising new candidates to our serodiagnostic toolbox but highlights the need for more antigen discovery studies that may have to be focused on regional performance.
Subject(s)
Antibodies, Protozoan , Antigens, Protozoan , Dog Diseases , Leishmaniasis, Visceral , Serologic Tests , Leishmaniasis, Visceral/diagnosis , Leishmaniasis, Visceral/veterinary , Leishmaniasis, Visceral/immunology , Dogs , Animals , Antigens, Protozoan/immunology , Antigens, Protozoan/genetics , Serologic Tests/methods , Humans , Dog Diseases/diagnosis , Dog Diseases/parasitology , Dog Diseases/immunology , Antibodies, Protozoan/blood , Sensitivity and Specificity , EthiopiaABSTRACT
Arthropod-borne viruses represent a crucial public health threat. Current arboviral serology assays are either labor intensive or incapable of distinguishing closely related viruses, and many zoonotic arboviruses that may transition to humans lack any serologic assays. In this study, we present a programmable phage display platform, ArboScan, that evaluates antibody binding to overlapping peptides that represent the proteomes of 691 human and zoonotic arboviruses. We confirm that ArboScan provides detailed antibody binding information from animal sera, human sera, and an arthropod blood meal. ArboScan identifies distinguishing features of antibody responses based on exposure history in a Colombian cohort of Zika patients. Finally, ArboScan details epitope level information that rapidly identifies candidate epitopes with potential protective significance. ArboScan thus represents a resource for characterizing human and animal arbovirus antibody responses at cohort scale.
Subject(s)
Antibodies, Viral , Arboviruses , Humans , Arboviruses/immunology , Arboviruses/isolation & purification , Animals , Antibodies, Viral/immunology , Antibodies, Viral/blood , Peptides/immunology , Peptides/chemistry , Zika Virus Infection/virology , Zika Virus Infection/immunology , Zika Virus Infection/blood , Zika Virus/immunology , Epitopes/immunology , Serologic Tests/methods , Arbovirus Infections/virology , Arbovirus Infections/immunology , Proteome , Colombia , Female , Peptide Library , Cell Surface Display Techniques , MaleABSTRACT
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/standardsABSTRACT
OBJECTIVE: This study aims to develop a predictive model for the detection of gastric cancer risk utilizing non-invasive parameters and to assess the model's effectiveness in risk stratification for gastric cancer (GC). METHODS: A case-control study was conducted among inpatients with various gastric diseases. These individuals were categorized into two groups: the gastric cancer group (138 cases) and the chronic non-atrophic gastritis (CNAG) group (319 cases). We employed a comprehensive panel of hematological, biochemical, and coagulation parameters derived from routine blood tests. Random Forest and Logistic regression analysis was used for feature selection and model building. Statistical analyses were performed using R version 4.2.3. RESULTS: Logistic regression analysis was employed to establish risk prediction models for GC, incorporating variables such as D-dimer, carcinoembryonic antigen (CEA), carbohydrate antigen 724 (CA724), and hemoglobin (HGB). A visual nomogram was generated as the final prediction model. The area under the receiver operating characteristic curve (AUC) for the training and test sets were 0.8093 [95% confidence interval (CI), 0.7541-0.8644], and 0.8076 [95% CI 0.7237-0.8915], respectively. Furthermore, we have developed an HTML file, featuring the Logistic equation, which enables real-time assessment of GC risk scores. CONCLUSION: The performance of this predictive model demonstrates its adequacy, making it a valuable and cost-effective noninvasive tool for identifying early gastric cancer (EGC) in patients. Consequently, this model may facilitate the implementation of targeted preventive and intervention strategies in clinical practice.