Investigation of a measles outbreak in Zimbabwe, 2010: potential of a point of care test to replace laboratory confirmation of suspected cases

SUMMARYBlood and oral fluid (OF) samples were collected from 103 suspected measles cases between February and November 2010 during a nationwide measles outbreak in Zimbabwe. Siemens measles IgM enzyme immunoassay (EIA) on serum, Microimmune measles IgM capture EIA on OF, real-time haemagglutinin (H) gene PCR and nested nucleocapsid (N) gene PCR on OF were performed, confirming 75 measles cases. These samples were then used to evaluate a newly developed point of care test (POCT) for measles and determine its potential for identifying measles cases in outbreaks. After performing POCTs on OF samples, nucleic acid was extracted from the used test strips and the measles H and N genes amplified by RT–PCR. The sensitivity, specificity, positive and negative predictive values of the POCT for IgM in OF was 75·0% [95% confidence interval (CI) 63·4–84·5], 96·2% (95% CI 80·4–99·9), 98·2% (95% CI 90·3–100) and 58·1% (95% CI 42·1–73·0), respectively. The N gene sequences showed high level of agreement between original OF and corresponding POCT strips. Measles genotype B3 was identified in all cases. We conclude that the measles POCT has the potential to be used, at the point of contact, in outbreak situations and provide molecular characterization of the virus at a later date.

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COVID-19 Seroprevalence among Healthcare Workers of a Large COVID-19 Hospital in Rome Reveals Strengths and Limits of Two Different Serological Tests

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18052650 ◽

2021 ◽

Vol 18 (5) ◽

pp. 2650

Author(s):

Giuseppe Vetrugno ◽

Daniele Ignazio La Milia ◽

Floriana D’Ambrosio ◽

Marcello Di Pumpo ◽

Roberta Pastorino ◽

...

Keyword(s):

Blood Test ◽

Healthcare Workers ◽

Point Of Care ◽

Venous Blood ◽

Administrative Staff ◽

Serological Tests ◽

Predictive Values ◽

Work From Home ◽

Significant Difference ◽

Sensitivity Specificity

Healthcare workers are at the forefront against COVID-19, worldwide. Since Fondazione Policlinico Universitario A. Gemelli (FPG) IRCCS was enlisted as a COVID-19 hospital, the healthcare workers deployed to COVID-19 wards were separated from those with limited/no exposure, whereas the administrative staff were designated to work from home. Between 4 June and 3 July 2020, an investigation was conducted to evaluate the seroprevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immunoglobulin (IgG) antibodies among the employees of the FPG using point-of-care (POC) and venous blood tests. Sensitivity, specificity, and predictive values were determined with reverse-transcription polymerase chain reaction on nasal/oropharyngeal swabs as the diagnostic gold standard. The participants enrolled amounted to 4777. Seroprevalence was 3.66% using the POC test and 1.19% using the venous blood test, with a significant difference (p < 0.05). The POC test sensitivity and specificity were, respectively, 63.64% (95% confidence interval (CI): 62.20% to 65.04%) and 96.64% (95% CI: 96.05% to 97.13%), while those of the venous blood test were, respectively, 78.79% (95% CI: 77.58% to 79.94%) and 99.36% (95% CI: 99.07% to 99.55%). Among the low-risk populations, the POC test’s predictive values were 58.33% (positive) and 98.23% (negative), whereas those of the venous blood test were 92.86% (positive) and 98.53% (negative). According to our study, these serological tests cannot be a valid alternative to diagnose COVID-19 infection in progress.

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Secondary Analysis of an Electronic Surveillance System Combined with Multi-focal Interventions for Early Detection of Sepsis

Applied Clinical Informatics ◽

10.4338/aci-2016-07-ra-0112 ◽

2017 ◽

Vol 26 (01) ◽

pp. 47-66 ◽

Cited By ~ 7

Author(s):

Bonnie Westra ◽

Sean Landman ◽

Pranjul Yadav ◽

Michael Steinbach

Keyword(s):

Early Detection ◽

Surveillance System ◽

Point Of Care ◽

Management Strategies ◽

Secondary Analysis ◽

Length Of Hospital Stay ◽

Separate Analysis ◽

Electronic Surveillance ◽

Predictive Values ◽

Sensitivity Specificity

SummarySummary: To conduct an independent secondary analysis of a multi-focal intervention for early detection of sepsis that included implementation of change management strategies, electronic surveil-lance for sepsis, and evidence based point of care alerting using the POC AdvisorTM application. Methods: Propensity score matching was used to select subsets of the cohorts with balanced covariates. Bootstrapping was performed to build distributions of the measured difference in rates/ means. The effect of the sepsis intervention was evaluated for all patients, and High and Low Risk subgroups for illness severity. A separate analysis was performed patients on the intervention and non-intervention units (without the electronic surveillance). Sensitivity, specificity, and the positive predictive values were calculated to evaluate the accuracy of the alerting system for detecting sepsis or severe sepsis/ septic shock.Results: There was positive effect on the intervention units with sepsis electronic surveillance with an adjusted mortality rate of –6.6%. Mortality rates for non-intervention units also improved, but at a lower rate of –2.9%. Additional outcomes improved for patients on both intervention and non-intervention units for home discharge (7.5% vs 1.1%), total length of hospital stay (-0.9% vs –0.3%), and 30 day readmissions (-6.6% vs –1.6%). Patients on the intervention units showed better outcomes compared with non-intervention unit patients, and even more so for High Risk patients. The sensitivity was 95.2%, specificity of 82.0% and PPV of 50.6% for the electronic surveillance alerts. Conclusion: There was improvement over time across the hospital for patients on the intervention and non-intervention units with more improvement for sicker patients. Patients on intervention units with electronic surveillance have better outcomes; however, due to differences in exclusion criteria and types of units, further study is needed to draw a direct relationship between the electronic surveillance system and outcomes.

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Evaluation of serum carbohydrate antigen 19-9 as a diagnostic marker for pancreatic malignancy

International Surgery Journal ◽

10.18203/2349-2902.isj20203762 ◽

2020 ◽

Vol 7 (9) ◽

pp. 2824

Author(s):

A.K.M. Ahsan Ullah ◽

S. M. Ferdous Ahmed ◽

A. S. M. Lokman Hossain Chowdhury ◽

Saad Mohammed ◽

M. Mozammel Haque ◽

...

Keyword(s):

Tumor Marker ◽

Carbohydrate Antigen ◽

Predictive Values ◽

Benign Condition ◽

Pancreatic Diseases ◽

Pancreatic Malignancy ◽

Serum Carbohydrate Antigen ◽

High Level ◽

Sensitivity Specificity ◽

Medical University

Background: Carbohydrate antigen (CA) 19-9 is considered as a tumor marker in biliary-pancreatic malignancy. Though a high level may indicate the presence of a malignant disorder, it may rise even in benign condition. Similarly, the value may be normal even in malignant condition.Methods: An observational comparative study was conducted in the Department of Surgery of Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka from 01 June 2016 to 31 May 2017 to find out the sensitivity and specificity of CA 19-9 as a tumor marker in pancreatic malignancy in our perspective and to find out a cut-off value of CA 19-9 which might prove as a definitive indication of pancreatic malignancy.Results: The study shows when the cut off value of CA 19-9 is 37 U/ml. The sensitivity, specificity, positive and negative predictive values (PPV and NPV) were 77.8%, for all four characteristics respectively. But if the serum CA 19-9 threshold used to diagnose pancreatic cancer was raised to 100 and 120, sensitivity decreased to 72.2% and 66.7% and NPV decreased to 76.2% and 73.9% respectively. However, specificity increased to 88.9% and 94.4% and PPV increased to 86.7% and 92.3% respectively.Conclusions: Serum CA 19-9 level may be considered as an important determinant in the diagnosis of malignant pancreatic diseases and to assess the resectability of the lesions preoperatively, but other adjuncts are necessary in the overall management of pancreatic diseases.

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Rapid, sensitive and specific SARS coronavirus-2 detection: a multi-center comparison between standard qRT-PCR and CRISPR based DETECTR.

10.1101/2020.07.27.20147249 ◽

2020 ◽

Cited By ~ 2

Author(s):

Eelke Brandsma ◽

Han JMP Verhagen ◽

Thijs J.W. van de Laar ◽

Eric C.J. Claas ◽

Marion Cornelissen ◽

...

Keyword(s):

Point Of Care ◽

Diagnostic Testing ◽

Added Value ◽

N Gene ◽

Analytical Sensitivity ◽

Qrt Pcr ◽

Negative Results ◽

Point Of Care Test ◽

Ribonucleoprotein Complexes ◽

Large Patient

Recent advances in CRISPR-based diagnostics suggest that DETECTR, a combination of isothermal reverse transcriptase loop mediated amplification (RT-LAMP) and subsequent Cas12 bystander nuclease activation by amplicon targeting ribonucleoprotein complexes, could be a faster and cheaper alternative to qRT-PCR without sacrificing sensitivity/specificity. Here we compare qRT-PCR with DETECTR to diagnose COVID-19 on 378 patient samples and report a 95% reproducibility. Patient sample dilution assays suggest a higher analytical sensitivity of DETECTR compared to qRT-PCR, however, this was not confirmed in a large patient cohort. The data showed that both techniques are equally sensitive in detecting SARS-CoV-2 providing an added value of DETECTR to the currently used qRT-PCR platforms. For DETECTR, different gRNAs can be used simultaneously to obviate negative results due to mutations in N-gene. Lateral flow strips, suitable as a point of care test (POCT), showed a 100% correlation to the high-throughput DETECTR assay. Importantly, DETECTR was 100% specific for SARS-CoV-2 and did not detect other human coronaviruses. As there is no need for specialized equipment, DETECTR could be rapidly implemented as a complementary technically independent approach to qRT-PCR thereby increasing the testing capacity of medical microbiological laboratories and relieving the existent PCR-platforms for routine non- SARS-CoV-2 diagnostic testing.

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Non-invasive hemoglobin measurement devices require refinement to match diagnostic performance with their high level of usability and acceptability

PLoS ONE ◽

10.1371/journal.pone.0254629 ◽

2021 ◽

Vol 16 (7) ◽

pp. e0254629

Author(s):

Melissa F. Young ◽

Kelley Raines ◽

Farhad Jameel ◽

Manal Sidi ◽

Shaiana Oliveira-Streiff ◽

...

Keyword(s):

Clinical Performance ◽

Point Of Care ◽

Venous Blood ◽

Smartphone Application ◽

Multiple Point ◽

Structured Interviews ◽

Resource Limited ◽

User Acceptability ◽

High Level ◽

Sensitivity Specificity

Anemia remains an important global health problem. Inexpensive, accurate, and noninvasive solutions are needed to monitor and evaluate anemia in resource-limited settings. We evaluated the performance of multiple point-of-care hemoglobin devices, including a novel noninvasive smartphone application tested on Apple® and Android® cell phones, Masimo Pronto®, and HemoCue® Hb-301 and Hb-801, against a gold-standard hematology analyzer (reference hemoglobin) using venous blood. We examined correlations between hemoglobin devices and reference hemoglobin, device accuracy (average bias, Bland-Altman plots, clinical performance) and classification bias (sensitivity, specificity) among 299 refugees (10mo-65y) in Atlanta, GA. Semi-structured interviews (n = 19) with participants and staff assessed usability and acceptability. Mean reference hemoglobin was 13.7 g/dL (SD:1.8) with 12.5% anemia. Noninvasive hemoglobin devices were not well correlated with reference hemoglobin (Apple® R2 = 0.08, Android® R2 = 0.11, Masimo Pronto® R2 = 0.29), but stronger correlations were reported with HemoCue® Hb-301 (R2 = 0.87) and Hb-801 (R2 = 0.88). Bias (SD) varied across each device: Apple®: -1.6 g/dL (2.0), Android®: -0.7 g/dL (2.0), Masimo Pronto®: -0.4 g/dL (1.6), HemoCue® Hb-301: +0.4 g/dL (0.7) and HemoCue® Hb-801: +0.2 g/dL (0.6). Clinically acceptable performance (within ± 1 g/dL of reference hemoglobin) was higher for the invasive devices (HemoCue® Hb-301: 90.3%; HemoCue® Hb-801: 93.4%) compared to noninvasive devices (Apple®: 31.5%; Android®: 34.6%; Masimo Pronto®: 49.5%). Sensitivity and specificity were 63.9% and 48.2% for Apple®, 36.1% and 67.6% for Android®, 45.7% and 85.3% for Masimo Pronto®, 54.3% and 97.6% for HemoCue® Hb-301, and 66.7% and 97.6% for HemoCue® Hb-801. Noninvasive devices were considered easy to use and were the preferred method by participants. Among the only studies to compare multiple point-of-care approaches to hemoglobin testing, the diagnostic ability of HemoCue® was comparable to reference hemoglobin, while noninvasive devices had high user acceptability but considerable biases. Improvements in noninvasive device performance and further testing in anemic populations are recommended before broader use.

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11C-hydroxy-ephedrine-PET/CT in the Diagnosis of Pheochromocytoma and Paraganglioma

Cancers ◽

10.3390/cancers11060847 ◽

2019 ◽

Vol 11 (6) ◽

pp. 847 ◽

Cited By ~ 1

Author(s):

Achyut Ram Vyakaranam ◽

Joakim Crona ◽

Olov Norlén ◽

Per Hellman ◽

Anders Sundin

Keyword(s):

Blood Pressure ◽

Systolic Blood Pressure ◽

Standardized Uptake Value ◽

Adrenal Incidentalomas ◽

Predictive Values ◽

Catecholamine Excess ◽

Clinical Scenarios ◽

Pet Ct ◽

Sensitivity Specificity

Pheochromocytomas (PCC) and paragangliomas (PGL) may be difficult to diagnose because of vague and uncharacteristic symptoms and equivocal biochemical and radiological findings. This was a retrospective cohort study in 102 patients undergoing 11C-hydroxy-ephedrine (11C-HED)-PET/CT because of symptoms and/or biochemistry suspicious for PCC/PGL and/or with radiologically equivocal adrenal incidentalomas. Correlations utilized CT/MRI, clinical, biochemical, surgical, histopathological and follow-up data. 11C-HED-PET/CT correctly identified 19 patients with PCC and six with PGL, missed one PCC, attained one false positive result (nodular hyperplasia) and correctly excluded PCC/PGL in 75 patients. Sensitivity, specificity, positive and negative predictive values of 11C-HED-PET/CT for PCC/PGL diagnosis was 96%, 99%, 96% and 99%, respectively. In 41 patients who underwent surgical resection and for whom correlation to histopathology was available, the corresponding figures were 96%, 93%, 96% and 93%, respectively. Tumor 11C-HED-uptake measurements (standardized uptake value, tumor-to-normal-adrenal ratio) were unrelated to symptoms of catecholamine excess (p > 0.05) and to systolic blood pressure (p > 0.05). In PCC/PGL patients, norepinephrine and systolic blood pressure increased in parallel (R2 = 0.22, p = 0.016). 11C-HED-PET/CT was found to be an accurate tool to diagnose and rule out PCC/PGL in complex clinical scenarios and for the characterization of equivocal adrenal incidentalomas. PET measurements of tumor 11C-HED uptake were not helpful for tumor characterization.

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Dynamic characteristic of SARS-CoV-2 and its antibody detection

The Journal of Medical Research ◽

10.31254/jmr.2021.7401 ◽

2021 ◽

Vol 7 (4) ◽

pp. 100-101

Author(s):

Bahrul Fikri ◽

◽

Andi Dwi Bahagia Febriani ◽

Muhamad Ali ◽

Nasrum Massi ◽

...

Keyword(s):

Point Of Care ◽

Diagnostic Testing ◽

Rapid Test ◽

Turnaround Time ◽

Antibody Detection ◽

Point Of Care Test ◽

Specimen Collection ◽

Excess Morbidity ◽

Sensitivity Specificity ◽

Testing Solution

To prevent excess morbidity and mortality of Covid-19, a prompt and accurate diagnosis is crucial. Antibody-based rapid diagnostic test (RDT) is a rapid, fairly reliable, and useful diagnostic testing solution for COVID-19. As a point-of-care test with fast turnaround time, the kit permits quick screening in hospitals to avoid the crowding of specimen collection. However, available RDTs kits have different sensitivity, specificity, and accuracy profiles due to antigen and antibody variability because of the sequence mutation of the SARS-CoV-2 gene. Therefore, it is strongly recommended to either re-measure the accuracy of a rapid test before using it in a different country or use tests developed based on local viral characteristics

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Characterization of Focal Liver Lesions using CEUS and MRI with Liver-Specific Contrast Media: Experience of a Single Radiologic Center

Ultraschall in der Medizin - European Journal of Ultrasound ◽

10.1055/s-0043-105264 ◽

2017 ◽

Vol 38 (06) ◽

pp. 619-625 ◽

Cited By ~ 19

Author(s):

Lukas Beyer ◽

Florian Wassermann ◽

Benedikt Pregler ◽

Katharina Michalik ◽

Janine Rennert ◽

...

Keyword(s):

Contrast Media ◽

Predictive Value ◽

False Negative ◽

Focal Liver Lesions ◽

Liver Lesions ◽

Predictive Values ◽

Negative Results ◽

False Negative Results ◽

Sensitivity Specificity

Abstract Aim The purpose of this study was to compare contrast-enhanced ultrasound (CEUS), magnetic resonance imaging (MRI) using liver-specific contrast agent and a combination of both for the characterization of focal liver lesions (FLL). Methods 83 patients with both benign and malignant liver lesions were examined using CEUS and MRI after the intravenous administration of liver-specific contrast media. All patients had inconclusive results from prior imaging examinations. Histopathological specimens could be obtained in 53 patients. Ultrasound was performed using a multi-frequency curved probe (1 – 6 MHz) after the injection of 1 – 2.4 ml ultrasound contrast media. The sensitivity, specificity, positive predictive value and negative predictive value of CEUS, MRI and a combination of both (CEUS + MRI) were compared. Results The sensitivity, specificity, positive and negative predictive values regarding lesion classification were 90.9 %, 70.6 %, 92.3 % and 66.6 %, respectively, for CEUS; 90.9 %, 82.4 %, 95.2 % and 70.0 %, respectively, for MRI; and 96.9 %, 70.6 %, 92.7 % and 85.7 % respectively, for CEUS + MRI. There were no statistically significant differences. 6 malignant lesions were missed using CEUS or MRI alone (false negatives). The use of both modalities combined reduced the false-negative results to 2. Conclusion CEUS and MRI with liver-specific contrast media are very reliable and of equal informative value in the characterization of focal liver lesions. The number of false-negative results can be decreased using a combination of the two methods.

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Diagnostic evaluation of the BD Affirm VPIII assay as a point-of-care test for the diagnosis of bacterial vaginosis, trichomoniasis and candidiasis

International Journal of STD & AIDS ◽

10.1177/0956462419895684 ◽

2020 ◽

Vol 31 (4) ◽

pp. 303-311

Author(s):

Fazana Dessai ◽

Makandwe Nyirenda ◽

Motshedisi Sebitloane ◽

Nathlee Abbai

Keyword(s):

Bacterial Vaginosis ◽

Predictive Value ◽

Trichomonas Vaginalis ◽

Point Of Care ◽

Candida Spp ◽

Vaginal Infections ◽

Sexually Transmitted ◽

Point Of Care Test ◽

Mother And Child ◽

Sensitivity Specificity

Untreated sexually transmitted infections and bacterial vaginosis (BV) pose a serious health risk to mother and child. Limited data exist on the use of the BD Affirm™ VPIII assay as a point-of-care test (POCT). The performance of the BD Affirm™ VPIII assay was compared with the BD Max™ vaginal assay for the diagnosis of BV, Trichomonas vaginalis (TV) and Candida spp. A total of 273 pregnant women were enrolled in this study and had provided two self-collected vaginal swabs. Sensitivity, specificity, positive predictive value, negative predictive value and prevalence were calculated. The prevalence of BV, candidiasis and trichomoniasis was 49.4, 57.2 and 10.3%, respectively. The BD Affirm™ VPIII assay showed a moderate sensitivity (79.8%) and a moderate specificity (80.3%) for diagnosing BV in all participants. The BD Affirm™ VPIII assay had an excellent specificity for Candida spp. and TV of 97.4 and 100%, respectively; however, the assay exhibited poor sensitivities of 52.9 and 46.4%, respectively. This study was the first to report on the performance of the BD Affirm™ VPIII assay as a POCT in an antenatal population. The assay was found to be unsuitable as a screening test for vaginal infections in pregnancy.

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Line Immunoblot Assay for Tick-Borne Relapsing Fever and Findings in Patient Sera from Australia, Ukraine and the USA

Healthcare ◽

10.3390/healthcare7040121 ◽

2019 ◽

Vol 7 (4) ◽

pp. 121 ◽

Cited By ~ 1

Author(s):

Jyotsna S. Shah ◽

Song Liu ◽

Iris Du Cruz ◽

Akhila Poruri ◽

Rajan Maynard ◽

...

Keyword(s):

Lyme Disease ◽

Recombinant Proteins ◽

Serological Detection ◽

Relapsing Fever ◽

Predictive Values ◽

Immunoblot Assay ◽

Clinical Criteria ◽

Laboratory Confirmation ◽

The Usa ◽

Sensitivity Specificity

Tick-borne relapsing fever (TBRF) is caused by spirochete bacteria of the genus Borrelia termed relapsing fever Borreliae (RFB). TBRF shares symptoms with Lyme disease (LD) caused by related Lyme disease Borreliae (LDB). TBRF and LD are transmitted by ticks and occur in overlapping localities worldwide. Serological detection of antibodies used for laboratory confirmation of LD is not established for TBRF. A line immunoblot assay using recombinant proteins from different RFB species, termed TBRF IB, was developed and its diagnostic utility investigated. The TBRF IBs were able to differentiate between antibodies to RFB and LDB and had estimated sensitivity, specificity, and positive and negative predictive values of 70.5%, 99.5%, 97.3%, and 93.4%, respectively, based on results with reference sera from patients known to be positive and negative for TBRF. The use of TBRF IBs and analogous immunoblots for LD to test sera of patients from Australia, Ukraine, and the USA with LD symptoms revealed infection with TBRF alone, LD alone, and both TBRF and LD. Diagnosis by clinical criteria alone can, therefore, underestimate the incidence of TBRF. TBRF IBs will be useful for laboratory confirmation of TBRF and understanding its epidemiology worldwide.

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