Point Of Care Screening Research Articles

Label-free Colorimetric Detection of Viral RNA Based on Clustered Regularly Interspaced Short Palindromic Repeats and Gold Nanoparticles with a Portable Device.

Viral infections, such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), are some of the most dangerous threats to humans. SARS-CoV-2 has caused a global pandemic, highlighting the unprecedented demand for rapid and portable diagnostic methods. To meet these requirements, we designed a label-free colorimetric platform that combines the clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated proteins (Cas) 12a system for naked-eye detection (named LFP). This method utilizes reverse transcription loop-mediated isothermal amplification (RT-LAMP) and the trans-cleavage activity of the CRISPR/Cas12a system to increase the sensitivity and specificity of the reaction. This platform can detect as few as 4 copies/μL of RNA and produces no false positive results when tested against the influenza virus. To better meet the requirements of point-of-care (POC) detection, we developed a portable device that can be applied in resource-poor and densely populated regions. The LFP assay holds great potential for application in resource-limited settings, and the label-free gold nanoparticle (AuNPs) probe can reduce costs, making it suitable for large-scale screening. We expect that the LFP assay will be promising for the POC screening of COVID-19.

Abstract LB232: Implementation of population-based risk assessment for hereditary cancer in primary care: Results from the Early Detection of Genetic Risk (EDGE) Trial

Abstract The EDGE (Early Detection of GEnetic risk) trial compared two population-based engagement strategies for identifying primary care patients with a family or personal history of cancer and offered eligible individuals genetic testing for cancer susceptibility (GT). A total of twelve clinics from two healthcare systems (6 clinics each) participated in Montana, Wyoming and Washington State. Clinics were cluster-randomized to one of two engagement approaches: 1) point of care screening (POC), conducted by clinic staff when a patient came in for their appointment and 2) direct patient engagement (DPE), where letter and email outreach facilitated online home screening. Patients who completed screening and met pre-specified personal and family history criteria were offered GT via a home-delivered saliva kit at no cost. The two primary outcomes of the trial were the fraction of active clinic patients who 1) completed the risk assessment tool and 2) completed GT. Logistic regression models were used to compare POC and DPE, allowing for overdispersion and including clinic as a design factor. Analyses in the screened population were adjusted for age, sex, personal and/or family history of cancer, and healthcare system. Over a 12-month engagement window, 95,623 patients were seen in the 12 clinics (Table 1). The POC approach resulted in a higher proportion screened for hereditary risk (19.1% vs. 8.7%), but a similar proportion completed testing (1.5% vs. 1.6%). Notably, the rate of testing among eligible patients approached via POC was approximately half the rate observed with DPE (24.7% vs. 44.7%). POC screen completers were less likely to have a personal history of cancer (9.1% vs. 10.7%), a significant family history of cancer (9.5% vs. 12.8%), and, if eligible, order a test kit (33.8% vs. 58.1%). Overall, a POC approach resulted in higher screening rates for familial cancer risk but a similar fraction completing GT, with DPE screeners self-selecting due to greater personal and/or family history of cancer. Analyses are ongoing to examine patient, clinic and system-level factors predicting screening and testing uptake, which can inform best practices for population-based hereditary cancer screening efforts. POC % (N) DPE % (N) Unadjusted OR (POC vs DPE) Adjusted OR * (POC vs DPE) p-value Patient Denominator 51,693 43,930 Completed Screening 19.1% (9892) 8.7% (3813) 2.49 - 0.0074 Completed GT 1.5% (757) 1.6% (717) 0.89 - 0.75 Screened Participants 9892 3813 % screened with any personal cancer history 9.1% (902) 10.7% (406) 0.77 <0.0001 % of screened with significant** family history of cancer 9.5% (935) 12.8% (487) - 0.69 <0.0001 % of screened found eligible for GT 31.0% (3070) 42.0% (1603) - 0.65 <0.0001 Participants eligible for GT 3070 1603 % of eligible who ordered test kit 33.8% (1039) 58.1% (932) - 0.43 <0.0001 % of eligible who completed GT 24.7% (757) 44.7% (717) - 0.49 <0.0001 *Adjusted ORs - Adjusted for age, sex, personal cancer history, family cancer history, healthcare system.**Significant family history: 2 or more first degree relatives with a high-risk cancer Citation Format: Elizabeth M. Swisher, Heather M. Harris, Barbara M. Norquist, Jeannine Brant, Brian Shirts, Sarah Knerr, Emerson J. Dusic, Faith Beers, Tesla N. Theoryn, DaLaina Cameron, Howard Cabral, Laurie A. Riemann, Michael Raff, Beth Devine, Deborah J. Bowen, Catharine Wang. Implementation of population-based risk assessment for hereditary cancer in primary care: Results from the Early Detection of Genetic Risk (EDGE) Trial [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB232.

Factors associated with knowledge and awareness of Hepatitis B in individuals of Chinese descent: Results from a mass point of care testing and outreach campaign in Toronto, Canada.

Migrants from hepatitis B virus (HBV) endemic regions are at high risk of having chronic infection. Despite this, HBV knowledge and awareness programming, and low-barrier screening methods such as point of care (POC) testing, among this group have yet to become routine. We conducted a mass HBV POC screening and knowledge and awareness campaign for individuals of Chinese descent in Toronto, Canada. POC screening was administered, then participants completed a knowledge questionnaire. Logistic regression identified associations between demographic factors and participants' level of HBV knowledge. From 2015 to 2018, 33 outreach events resulted in 891 individuals completing testing and the knowledge questionnaire. Individuals averaged 64.4 years old. Most, 62% (N = 552), were female, and 73.6% (N = 656) have been in Canada for <30 years. The average questionnaire score was 70.7% correct, with 65.2% (N = 581) demonstrating a high level of HBV knowledge. Post-secondary education (OR: 2.19, 95% CI: 1.41, 3.39), income of $50,000 to <$75,000 (OR: 2.74, 95% CI: 1.39, 5.43), and having familial history of HBV (OR: 1.72, 95% CI: 1.06, 2.78) were associated with high knowledge. The observed prevalence of HBV was 1.5%, with 13 individuals testing positive on the POC test and confirmatory laboratory testing. Improving knowledge and awareness of HBV is critical to empowering people, especially migrants who experience barriers to care, to pursue vaccination, testing, and treatment. Combining knowledge outreach and POC test campaigns, enabled discussion and screening for HBV with large numbers of people, and can be tailored for optimal effectiveness for specific groups.

Systematic, Point-of-Care Newborn Screening and Treatment for Sickle Cell Disease in Rural Mali, West Africa: Results from an Ongoing Implementation Project

Introduction: Sickle cell disease (SCD) is highly prevalent across sub-Saharan Africa and is a significant source of under-5 mortality. Accurate characterization of the disease prevalence is difficult to determine due to the absence of systematic newborn screening in most African countries. Mali is a land-locked West African country with a high burden of sickle cell disease. Despite the critical need for early diagnosis of SCD to improve survival, wide scale diagnostic efforts utilizing IEF or HPLC in sub-Saharan Africa have been limited by a paucity of laboratory equipment and trained personnel, unreliable supply chain for consumables, and overall expense. Point-of-Care (POC) testing for SCD is advancing rapidly and has the potential to reduce these barriers. This analysis will review the results of an ongoing POC newborn screening program for SCD at a single rural hospital in Mali and will evaluate the acceptance rates and basic outcomes of resource-adapted treatment. Methods: Between March 2019 and March 2023, all newborns at Koutiala Women's and Children's Hospital in Koutiala, Mali were offered screening for SCD with the HemoTypeSC ™ POC test kit (Silver Lake Research, California, USA). After verbal consent, heel-stick samples were procured within the first 24 hours of life. The samples were processed according to the package insert. The results were available within 10 minutes and were provided to the caregiver prior to discharge. Newborns who were found to have sickle cell disease were referred to the SCD treatment program where they were offered ongoing access to basic treatment measures such as antibiotic prophylaxis, malaria prevention, and hydroxycarbamide therapy. Parents of infants with HbSS who had not been seen in the clinic for follow-up within at least 6 months were contacted by phone at the time of this analysis to provide an update on their clinical status. Families of infants with HbS trait or HbC trait received appropriate genetic counseling. Statistical analysis was performed using a paired t-test. Results: 11,938 infants were born over the study period and 11,818 (99%) received POC screening. Screening results revealed Hb S trait; n=1,119 (9.47%), Hb C trait; n=1,285 (10.87%), Hemoglobin SS; n=81 (0.69%), Hemoglobin SC; n=100 (0.85%), and homozygous C; n=20 (0.54%). In all, 181 infants (1.54%) were found to have sickle cell disease and were offered follow-up care in the SCD treatment program at Koutiala Hospital. In addition, 2,404 infants (20.34%) were found to be carriers of either HbC trait or HbS trait. The mean age of those children diagnosed with HbSS and HbSC at the time of this analysis was 22.20mo (3-42mo) and 21.46mo (4-37mo), respectively. 89% (n=72) of the infants with HbSS received ongoing disease management. Penicillin prophylaxis was accepted in 82% (n=59) of the children in this cohort. Additionally, 44% (n=32) were started on hydroxycarbamide at a low, fixed dose (20ml/kg/day) based on disease severity parameters. Mean MCV for those children receiving hydroxycarbamide was 89.06fL (+/- 9.5fL) and for the non-hydroxycarbamide group was 79.83fL (+/- 14.3fL) (p= 0.025). While the most common reason for clinical follow-up was routine treatment, patients were also seen for fever, malaria treatment, and bone pain episodes. Based on clinical records and phone follow-up, there were two confirmed deaths (2.5%) in the HbSS cohort. One infant died of non-SCD complications on the first day of life and the other died at 6 months of age without returning to the clinic for follow-up treatment. Conclusions: This program is the first to examine the impact of systematic POC infant screening and treatment for SCD in rural Mali, West Africa. The low cost and rapidity of POC testing resulted in a high rate of newborns screened and positively impacted the success of clinical follow-up. POC testing results were comparable when reviewed alongside historical IEF-based screening at Koutiala Hospital (Table 1). The higher percentage of infants screened by POC when compared to IEF may have been slightly affected by an increase in the general awareness of SCD amongst the regional population. There was a high acceptance rate of ongoing clinical care (89%) and low death rate (2.5%) within the HbSS cohort which may be attributable to early access to diagnosis and treatment. Results from a larger patient size and longer treatment duration will provide more insight into the benefits of POC screening in this setting.

Review of linear and nonlinear models in breath analysis by Cyranose 320

Analysis of volatile organic compounds (VOCs) in breath specimens has potential for point of care (POC) screening due to ease of sample collection. While the electronic nose (e-nose) is a standard VOC measure across a wide range of industries, it has not been adopted for POC screening in healthcare. One limitation of the e-nose is the absence of mathematical models of data analysis that yield easily interpreted findings at POC. The purposes of this review were to (1) examine the sensitivity/specificity results from studies that analyzed breath smellprints using the Cyranose 320, a widely used commercial e-nose, and (2) determine whether linear or nonlinear mathematical models are superior for analyzing Cyranose 320 breath smellprints. This systematic review was conducted according to the guidelines of the Preferred Reporting Items for Systematic Review and Meta-Analyses using keywords related to e-nose and breath. Twenty-two articles met the eligibility criteria. Two studies used a linear model while the rest used nonlinear models. The two studies that used a linear model had a smaller range for mean of sensitivity and higher mean (71.0%–96.0%; M = 83.5%) compared to the studies that used nonlinear models (46.9%–100%; M = 77.0%). Additionally, studies that used linear models had a smaller range for mean of specificity and higher mean (83.0%–91.5%; M = 87.2%) compared to studies that used nonlinear models (56.9%–94.0%; M = 76.9%). Linear models achieved smaller ranges for means of sensitivity and specificity compared to nonlinear models supporting additional investigations of their use for POC testing. Because our findings were derived from studies of heterogenous medical conditions, it is not known if they generalize to specific diagnoses.

Evaluating HIV Rapid/Point of Care Testing among Risk Factor Groups in Ontario, 2011 to 2018

ObjectivesIn 2014, Ontario’s Point-of-Care (POC) test providers were advised to focus efforts on provincially defined priority populations who experience a greater risk of HIV. Our objective was to describe the POC program before, during and after this change, including tester characteristics, follow-up testing results, positive predictive value (PPV) over time, and trends and characteristics of those with reactive test results without a confirmatory serological specimen.MethodsTest-level data of POC screening and confirmatory results were extracted from the Public Health Ontario HIV Datamart. Final test results were defined based on results of the confirmatory blood sample, or the POC test for “non-reactive” tests. Testing volumes, percent of total tests, percent positivity and PPV were calculated overall, annually, and by exposure group.ResultsOverall testing volumes decreased by 39.8% between 2014 and 2018. The majority of confirmed positive tests were in the men who have sex with men (MSM) exposure category, followed by HIV-endemic and heterosexual – no identified risk (heterosexual—NIR). Overall percent positivity decreased from 0.59% in 2011 to 0.42% in 2015 (change of 0.17%, 95% CI 0.03% to 0.31%), increasing to 0.69% in 2018 (change of 0.27%, 95% CI 0.20% to 0.34%). Increases in percent positivity corresponded with a decrease in the overall proportion of tests conducted in low-risk populations. When compared to the heterosexual-NIR category, PPV was significantly higher for men who have sex with men – people who use injection drugs (MSM-PWID) (52.7% compared to 100%, P < .001), MSM (52.7% compared to 95.4%, P < .001), HIV-endemic (52.7% compared to 91.5%, P < .001), heterosexual – partner with identified risk (heterosexual—PIR) (52.7% compared to 77.3%, P = .042), and people who use injection drugs (PWID) (52.7% compared to 81.3%, P = 0.007). A total of 13.5% of reactive POC results did not have a serological sample submitted.ConclusionsTargeted testing towards populations at higher risk of HIV improved the overall test performance characteristics of Ontario’s POC testing program. While not unexpected, the large discrepancies between PPV in higher-risk, compared to lower-risk populations, suggests the need for greater awareness and messaging of the likelihood of false positive test results in different populations.

Identification of urinary biomarkers of colorectal cancer: Towards the development of a colorectal screening test in limited resource settings.

African colorectal cancer (CRC) rates are rising rapidly. A low-cost CRC screening approach is needed to identify CRC from non-CRC patients who should be sent for colonoscopy (a scarcity in Africa). To identify urinary metabolite biomarkers that, combined with easy-to-measure clinical variables, would identify patients that should be further screened for CRC by colonoscopy. Ideal metabolites would be water-soluble and easily translated into a sensitive, low-cost point-of-care (POC) test. Liquid-chromatography mass spectrometry (LC-MS/MS) was used to quantify 142metabolites in spot urine samples from 514 Nigerian CRC patients and healthy controls. Metabolite concentration data and clinical characteristics were used to determine optimal sets of biomarkers for identifying CRC from non-CRC subjects. Our statistical analysis identified N1, N12-diacetylspermine, hippurate, p-hydroxyhippurate, and glutamate as the best metabolites to discriminate CRC patients via POC screening. Logistic regression modeling using these metabolites plus clinical data achieved an area under the receiver-operator characteristic (AUCs) curves of 89.2% for the discovery set, and 89.7% for a separate validation set. Effective urinary biomarkers for CRC screening do exist. These results could be transferred into a simple, POC urinary test for screening CRC patients in Africa.

Highly Sensitive Immunoresistive Sensor for Point-Of-Care Screening for COVID-19.

Current point-of-care (POC) screening of Coronavirus disease 2019 (COVID-19) requires further improvements to achieve highly sensitive, rapid, and inexpensive detection. Here we describe an immunoresistive sensor on a polyethylene terephthalate (PET) film for simple, inexpensive, and highly sensitive COVID-19 screening. The sensor is composed of single-walled carbon nanotubes (SWCNTs) functionalized with monoclonal antibodies that bind to the spike protein of SARS-CoV-2. Silver electrodes are silkscreen-printed on SWCNTs to reduce contact resistance. We determine the SARS-CoV-2 status via the resistance ratio of control- and SARS-CoV-2 sensor electrodes. A combined measurement of two adjacent sensors enhances the sensitivity and specificity of the detection protocol. The lower limit of detection (LLD) of the SWCNT assay is 350 genome equivalents/mL. The developed SWCNT sensor shows 100% sensitivity and 90% specificity in clinical sample testing. Further, our device adds benefits of a small form factor, simple operation, low power requirement, and low assay cost. This highly sensitive film sensor will facilitate rapid COVID-19 screening and expedite the development of POC screening platforms.

Point-of-care hepatitis C screening with direct access referral to improve linkage to care among halfway house residents: a pilot randomised study.

Linkage to care among individuals with substance misuse remains a barrier to the elimination of the hepatitis C virus (HCV). We aimed to determine whether point-of-care (PoC) education, screening and staging for liver disease with direct access to hospitals would improve linkage to care among this group. All participants were offered PoC education and HCV screening. HCV-positive participants were randomised to standard care (controls) or direct access, which provided a direct pathway to hospitals. Linkage to care was determined by reviewing electronic medical records. Linkage of care cascade was defined as attendance at the specialist clinic, confirmation of viraemia by HCV RNA testing, discussion about HCV treatment and initiation of treatment. 351 halfway house residents were screened. The overall HCV prevalence was 30.5% (n = 107), with 69 residents in the control group and 38 in the direct access group. The direct access group had a significantly higher percentage of cases linked to specialist review for confirmatory RNA testing (63.2% vs. 40.6%, p = 0.025), HCV treatment discussion (p = 0.009) and treatment initiation (p = 0.01) compared to the controls. Overall, only 12.6% (n = 13) had treatment initiation during follow-up. PoC HCV screening with direct access referral had significantly higher linkage to HCV treatment initiation (adjusted odds ratio 9.13, p = 0.005) in multivariate analysis. PoC HCV screening with direct access improves linkage to care and simplifies the HCV care cascade, leading to improved treatment uptake. PoC education, screening, diagnosis and treatment may be an effective strategy to achieving HCV micro-elimination in this population.

Point-of-care diagnosis of cervical cancer: potential protein biomarkers in cervicovaginal fluid.

Cervical cancer (CxCa) is preventable and treatable via vaccination and screening. Cervicovaginal fluid (CVF) represents the physiological components of the female genital tract. These components are suitable to be utilized for clinical purposes, therefore, making CVF a suitable material for disease screening approaches. Due to high false-negative result rates and low attendance of current expensive routine CxCa screening methods, it has become more important to develop a point-of-care (POC) screening method that every single woman could reach worldwide. For this purpose, various self-usage apparatus have been developed for screening of the human papilloma virus (HPV) infection. Furthermore, due to the low specificity of HPV tests and the high clearance rate of HPV infections, many patients undergo overtreatment. Since proteins play an important role in cellular process and carcinogenesis, it is appropriate to use proteins in a simple screening test for the detection of carcinogenesis. In this article, POC screening tests and the studies of discovery of CVF protein biomarkers will be overviewed to consider the development of a method that can be used for the rapid and conceivable screening method of CxCa.

Immuno-chromatic probe based lateral flow assay for point-of-care detection of Japanese encephalitis virus NS1 protein biomarker in clinical samples using a smartphone-based approach.

Lateral flow assays (LFAs) are one of the most economical, point-of-care (PoC) diagnostic assays that exploit the colorimetric properties of gold nanoparticles (AuNPs). Up to the best of our knowledge, no rapid antigen-based LFA exists for Japanese Encephalitis Virus (JEV) detection. Herein, we have reported a novel portable sandwich-type LFA for on-site detection of the non-structural 1 (NS1) secretory protein of JEV. In-house JEV NS1 antibodies (Abs) were generated and labelled with AuNPs as immunoprobes. A glass fibre membrane conjugate pad was soaked with AuNPs–Ab solution, while the JEV NS1 Ab and anti-rabbit IgG 2° Ab were coated as the test and control lines, respectively, on a nitrocellulose (NC) membrane. Different layers of the LFA were fabricated and various parameters were standardised for optimum colour intensity development. JEV negative serum samples spiked with JEV NS1 Ags (linear range – 1 pg ml−1 to 1 μg ml−1) were applied onto the sample pad and the intensity of the red colour developed on the test line increased with increasing concentration of Ag. The visual limit of detection (LOD) determined from the LFA was 10 pg ml−1, which corresponded to the LOD determined by the graphical data obtained from ImageJ software and the Colorimeter smartphone application. Furthermore, the colorimetric based immunosensor showed minimal non-specific detection of other closely related flaviviral NS1 Ags in the spiked serum, provided a rapid result within 10 min, showed storage stability up to a month at 4 °C, successfully detected the JEV NS1 protein in clinically infected pig serum samples, and hence, may be developed into a PoC screening diagnostic kit for JEV.

Point-of-care Hb measurement in pooled capillary blood by a portable autoanalyser: comparison with venous blood Hb measured by reference methods in cross-sectional and longitudinal studies.

Population-based surveys commonly use point-of-care (POC) methods with capillary blood samples for estimating Hb concentrations; these estimates need to be validated by comparison with reference methods using venous blood. In a cross-sectional study in 748 participants (17-86 years, 708 women, Hb: 5·1 to 18·2 g/dl) from Hyderabad, India, we validated Hb measured from a pooled capillary blood sample by a POC autoanalyser (Horiba ABX Micros 60OT, Hb-C-AA) by comparison with venous blood Hb measured by two reference methods: POC autoanalyser (Hb-V-AA) and cyanmethemoglobin method (Hb-V-CM). These comparisons also allowed estimation of blood sample-related and equipment-related differences in the Hb estimates. We also conducted a longitudinal study in 426 participants (17-21 years) to measure differences in the Hb response to iron folate (IFA) treatment by the capillary blood POC method compared with the reference methods. In the cross-sectional study, Bland-Altman analyses showed trivial differences between source of blood (Hb-C-AA and Hb-V-AA; mean difference, limits of agreement: 0·1, -0·8 to 1·0 g/dl) and between analytical methods (Hb-V-AA and Hb-V-CM; mean difference, limits of agreement: < 0·1, -1·8 to 1·8 g/dl). Cross-sectional anaemia prevalence estimated using Hb-C-AA did not differ significantly from Hb-V-CM or Hb-V-AA. In the longitudinal study, the Hb increment in response to IFA intervention was not different when using Hb-C-AA (1·6 ± 1·7 g/dl) compared with Hb-V-AA (1·7 ± 1·7 g/dl) and Hb-V-CM (1·7 ± 1·7 g/dl). The pooled capillary blood-autoanalyzer method (Hb-C-AA) offers a practical and accurate way forward for POC screening of anaemia.

Performance evaluation of Truenat™ Beta CoV & Truenat™ SARS-CoV-2 point-of-care assays for coronavirus disease 2019.

Background & objectives:The rapid diagnosis of coronavirus disease 2019 (COVID-19) is a significant step towards the containment of the virus. The surge of COVID-19 cases in India and across the globe necessitates a rapid and sensitive molecular assay. Rapid point-of-care (PoC) assays (Truenat Beta CoV and Truenat SARS-CoV-2 assays) for the diagnosis of COVID-19 have been developed which are expected to shorten the turnaround time of reporting of results and also can be used for field investigations of COVID-19. The objectives of the study were to validate the performance of Truenat Beta CoV and Truenat SARS-CoV-2 PoC assays for the detection of SARS-CoV-2 infected cases with reference to analytical sensitivity, precision/inter-machine variation, clinical sensitivity and clinical specificity.Methods:The rapid PoC screening and confirmatory assays were prospectively validated at the State Level Virus Research and Diagnostic Laboratory at Bangalore Medical College and Research Institute, Bengaluru, under technical supervision by the Indian Council of Medical Research-National Institute of Virology (ICMR-NIV), Pune. Real-time reverse transcription-polymerase chain reaction (rRT-PCR) was considered as the reference standard against which the rapid assays were validated for all samples tested based on analytical sensitivity, precision/inter-machine variation, clinical sensitivity and clinical specificity.Results:Truenat Beta CoV and Truenat SARS-CoV-2 assays showed concordant results when compared with the reference standard rRT-PCR. These PoC assays exhibited 100 per cent sensitivity, specificity, positive predictive value and negative predictive value.Interpretation & conclusions:Truenat Beta CoV and Truenat SARS-CoV-2 assays showed concordance with the reference standard assay and may be recommended for screening and confirmation of SARS-CoV-2 in the field settings.

Design of a study to implement population-based risk assessment for hereditary cancer genetic testing in primary care

Identifying patients with high genetic risk for cancer has important clinical ramifications, but hereditary cancer risk is often not identified because of testing barriers at both the provider and patient level. It is unknown how to best implement appropriate genetic testing and follow-up care into an operating primary care clinic. Implementation studies to date have been conducted in high resourced facilities under optimal conditions, often not at the clinic level. This study aims to compare and evaluate two population-wide engagement strategies for identifying members of a primary care clinic's population with a family or personal history of cancer and offering high-risk individuals genetic testing for cancer susceptibility mutations. The two engagement strategies are: 1) point of care screening (POC), conducted when a patient is scheduled for an appointment and 2) direct patient engagement (DPE), where outreach provides the patient an opportunity to complete screening online on their own time. The study will identify changes, problems, and inefficiencies in clinical flow during and after the implementation of risk assessment and genomic testing for cancer risk across primary care clinics. It will also evaluate the effects of the two engagement strategies on patient, provider, and clinic leader outcomes, including perceptions of benefits, harms, and satisfaction with the engagement strategy and process of cancer risk assessment and genetic testing, across gender, racial/ethnic, socioeconomic, and genetic literacy divides. Finally, the study will evaluate the cost-effectiveness and budget impact of each engagement strategy.

Prevalence of Undiagnosed Diabetes and Prediabetes in the Dental Setting: A Systematic Review and Meta-Analysis.

Background With the close link between diabetes mellitus (DM) and periodontal disease (PD), dentists have an unrealized opportunity to make a chance discovery of a patient's medical condition. Unlike in the medical setting, information on the point of care (PoC) and opportunistic screening for DM in the dental setting is limited. To make a reliable estimate on the prevalence of undiagnosed type 2 diabetes mellitus (T2DM) and prediabetes among dental patients in the dental setting and to assist healthcare planners in making an informed decision, information on the disease frequency and strategies employed to address this issue is of paramount importance. Objectives To summarize the data on the prevalence of undiagnosed T2DM and prediabetes amongst dental patients and further explore the effectiveness of the PoC screening and its implication for use in the dental setting. Methods A MEDLINE-PubMed, EMBASE, Web of Science, and Cochrane Library search was conducted with no time specification. Information on study characteristics and diagnostic parameters was retrieved for meta-analysis. All the studies were assessed for methodological quality using the QUADAS-2 tool. Proportions were presented in tables and forest plots. All statistical analysis was performed using the MedCalc software. Results Nine studies met the inclusion criteria. The proportion of dental patients identified to be at a risk of hyperglycaemia with the PoC screening using random blood glucose (RBG) and HbA1 was 32.47% and 40.10%, whilst the estimated proportion with undiagnosed T2DM and prediabetes was identified as 11.23% and 47.38%. Conclusion A significant proportion of dental patients can be identified as undiagnosed T2DM and prediabetes. Targeted opportunistic screening is a feasible approach and can help reduce the prevalence of undiagnosed T2DM and prediabetes.

Point-of-Care Tests for Hepatitis B Are Associated with A Higher Linkage to Care and Lower Cost Compared to Venepuncture Sampling During Outreach Screenings in an Asian Migrant Population.

Background:This study compares venepuncture versus point-of-care (POC) HBsAg tests on screening cost and linkage to care in prospective outreach screenings in an Asian population in three major cities in Belgium between 10/2014 and 5/2018.Methods:Two community outreach screening programs were organised between 10/2014 and 5/2018. The first screening program used venepuncture and serologic testing for HBsAg. In the second program, HBsAg was tested in finger stick blood POC tests. Positive results were confirmed during outpatient visits with serologic testing. Linkage to care was defined as having received specialist care follow-up with at least one abdominal ultrasound within three months of screening.Results:For 575 participating individuals, 571 valid results were obtained, 456 with venepuncture, and 115 using POC testing. Overall HBsAg seroprevalence was 6.8%. Linkage to care was higher when using POC testing compared to venepuncture (86% or n = 6/7 versus 34% or n = 11/32; p = 0.020). The POC screening program was economically more attractive with a total cost of € 1,461.8 or € 12.7 per person screened compared to € 24,819 or € 54.0 per person screened when using venepuncture testing. Results and an appointment for specialist care follow-up were given onsite with POC testing, while with venepuncture testing; results were sent within 20–45 days.Conclusion:In an Asian migrant population in Belgium with an HBsAg seroprevalence of 6.8%, HBV screening based on POC tests resulted in lower costs per person screened (76.5% lower), and higher linkage to care (2.5 times).

1358-P: Point of Care OGTT for the Screening of Gestational Diabetes: A Feasible Proposal for Low-Resource Settings

Due to the ubiquity of risk factors associated with gestational diabetes (GDM) in Mexican women and the low availability of the Oral Glucose Tolerance Test (OGTT), we compared the efficacy of two point of care (POC) models for GDM detection against the plasmatic 2hr OGTT-75gr in primary health care clinics in Mexico. We evaluated 328 pregnant women without previous diabetes diagnosis from a prospective cohort study “Cuido mi embarazo”; all of them were tested with the gold standard plasmatic 2hr OGTT-75gr for the diagnosis of GDM based on the ADA 2019 criteria. Simultaneously, we measured with a glucometer (ACCU-CHEK instant®) the glucose concentration either by capillary whole blood (172 measures) or from venous whole blood (156 measures). We evaluated the diagnostic accuracy by calculating the sensitivity, specificity, and ROC curve of each of the glucometer test results compared to the plasmatic test. For the first model, POC venous OGTT, the incidence of GDM was 41.66% compared to 7.05% of the plasmatic test. The ROC area under the curve for GDM prediction was 0.81 (95% CI 0.77-0.85), with a sensitivity of 100% and specificity of 62.8%. The low specificity is dependent on the fasting venous value of 64% since it was compared to 95% and 97% specificity of the 1hr and 2hr values, respectively. The second model, POC capillary OGTT, had an incidence of GDM of 30.23% compared to 8.13% of the plasmatic test. It had lower sensitivity (78.57%) and higher specificity (74.1%) compared to the first model, having an overall 0.76 (95% CI 0.65-0.88) ROC area under the curve for GDM prediction. We propose POC venous OGTT as a feasible diagnostic alternative for low resource settings where laboratory infrastructure is not available. Its positive bias could be beneficial since the treatment and control of early cases is related to better health outcomes for the moms and their babies. Further analysis is needed to improve GDM, POC screening interventions. Disclosure H. Gallardo: None. J. Lomelin-Gascon: Other Relationship; Self; Lilly Global Health Partnership. L.A. Martinez: Other Relationship; Self; Lilly Global Health Partnership. A. Montoya: None. E. Reyes-Muñoz: None. R.C. Tapia-Conyer: None. Funding Eli Lilly and Company

Rapid point of care test for detecting urogenital Chlamydia trachomatis infection in nonpregnant women and men at reproductive age.

Chlamydia trachomatis (C trachomatis) is one of the most frequent sexually transmitted infections and a source of deleterious effects on the reproductive health of men and women. Because this infection is likely asymptomatic and is associated with subfertility, ectopic pregnancy, and chronic pain, its presence needs to be confirmed. Technologies available for the diagnosis of C trachomatis infection can be classified into tests performed in a laboratory and rapid tests at the point of care (POC tests). Laboratory-based tests include culture, nucleic acid amplification tests, enzyme immunoassays (EIA), direct fluorescent antibody, nucleic acid hybridization, and transformation tests. Rapid tests include solid-phase EIA and solid-phase optical immunoassay. POC tests can be performed within 30 minutes without the need for expensive or sophisticated equipment. The principal advantage of this technology is the immediate presentation of results with the subsequent possibility to start the treatment of infected patients immediately. To determine the diagnostic accuracy of rapid point-of-care (POC) testing for detecting urogenital C trachomatis infection in nonpregnant women and men of reproductive age, as verified with nucleic acid amplification tests (NAATs) as the reference standard. In November 2019 we searched CENTRAL, MEDLINE, Embase and LILACS. We also searched Web of Science, two trials registries and an abstract database. We screened reference lists of included studies for additional references. We included diagnostic accuracy studies of symptomatic or asymptomatic nonpregnant women and men reproductive age. Included trials should have prospectively enrolled participants without previous diagnostic testing, co-infections or complications and consecutively or through random sampling at primary or secondary care facilities. Only studies reporting that all participants received the index test and the reference standard and presenting 2 x 2 data were eligible for inclusion. We excluded diagnostic case-control studies. Two review authors independently screened titles and abstracts for relevance. Two review authors independently, and in duplicate, assessed eligibility, extracted data, and carried out quality assessment. We resolved differences through consensus or by involving a third review author. We assessed studies for methodological quality using QUADAS-2 and used meta-analysis to combine the results of studies using the bivariate approach to estimate the expected sensitivity and specificity values. We assessed the quality of the evidence using GRADE criteria and explored sources of heterogeneity. We included a total of 19 studies, with 13,676 participants, that assessed the diagnostic accuracy of POC tests for C trachomatis infection in nonpregnant women and men of reproductive age, as verified with NAATs as the reference standard. Rapid tests were provided by the distributors in nine studies. Seven studies recruited a predominantly high risk or symptomatic population; the studies were conducted in America, Asia, Africa, Europe and Oceania, with a median prevalence of 10% (range 8% to 28%); nine different brands were assessed. The mean sensitivity for rapid tests for detecting urogenital infection was 0.48 (95% confidence interval (CI) 0.39 to 0.58; low-quality evidence) with a mean specificity of 0.98 (95% CI 0.97 to 0.99; moderate-quality evidence). We explored sources of heterogeneity by looking into differences in diagnostic accuracy according to the specimen (endocervical versus urine or vaginal), symptoms among participants (symptomatic versus asymptomatic), and setting (low/middle-income versus high-income countries). Likelihood ratio tests were not significantly different in terms of sensitivity or specificity by specimen (P = 0.27) or setting (P = 0.28); for this reason, these covariates do not appear to explain the observed variability. Included studies did not provide enough information to assess the 'presence of symptoms' covariate. We downgraded the quality of evidence because of some limitations in applicability and heterogeneity. Based on the results of this systematic review, the POC test based on antigen detection has suboptimal sensitivity but good specificity. Performance of this test translates, on average, to a 52% chance of mistakenly indicating absence of infection and a 2% chance of mistakenly pointing to the presence of this condition. Because of its deleterious consequences for reproductive health, and considering the current availability of safe and effective interventions to treat C trachomatis infection, the POC screening strategy should not be based on a rapid diagnostic test for antigen detection. Research in this topic should focus on different technologies.

Time matters: Point of care screening and streamlined linkage to care dramatically improves hepatitis C treatment uptake in prisoners in England

BackgroundIn England, opt-out dry blood spot prison screening for HIV, hepatitis B and hepatitis C (HCV) has been introduced to scale-up access to care. Recent advances in point-of-care HCV diagnostics provide an opportunity to improve diagnosis and treatment uptake. We compared the retention along and time intervals between each aspect of the HCV care continuum for an alternative rapid point-of-care-testing and simplified treatment strategy with existing national opt-out HCV dry blood spot testing and treatment at a large remand prison in West London. MethodsBetween September 2017 and December 2018 universal opt-out dry blood spot HCV testing, clinical assessment and treatment uptake were recorded at Her Majesty's Prison Wormwood Scrubs. Outcomes were compared to a point-of-care-based (salivary Oraquick® anti-HCV screening and Xpert® HCV fingerstick viral load) screening and streamlined treatment pathway offered to all new arrivals to the HMP Wormwood Scrubs substance misuse unit, which ran in parallel to dry blood spot testing between September and December 2018. ResultsDuring the study period 2442 out of 5239 inmates (46.6%) underwent dry blood spot screening, resulting in 62 (2.6%) HCV RNA positive cases. Thirteen (21.3%) individuals commenced therapy and no viral relapse cases were observed to date. In comparison, 162 out of 181 (89.5%) inmates admitted to the substance misuse unit agreed to rapid point-of-care testing; 20 (12.3%) HCV RNA positive cases. Seventeen (85.0%) of eligible inmates commenced treatment. The median length of stay (90 vs 30 days), time to screening (6 vs 2 days), assessment (14 vs 3 days) and treatment (36 vs 1 day) were shorter for the rapid point-of-care screen-and-treat group. ConclusionCurrent scaling-up of prison dry blood spot HCV screening and treatment in England is sub-optimal. In our setting, the cascade of care is time and resource sensitive and is greatly improved by the introduction of a simplified screen-and-treat strategy.

2D Materials in Development of Electrochemical Point-of-Care Cancer Screening Devices.

Effective cancer treatment requires early detection and monitoring the development progress in a simple and affordable manner. Point-of care (POC) screening can provide a portable and inexpensive tool for the end-users to conveniently operate test and screen their health conditions without the necessity of special skills. Electrochemical methods hold great potential for clinical analysis of variety of chemicals and substances as well as cancer biomarkers due to their low cost, high sensitivity, multiplex detection ability, and miniaturization aptitude. Advances in two-dimensional (2D) material-based electrochemical biosensors/sensors are accelerating the performance of conventional devices toward more practical approaches. Here, recent trends in the development of 2D material-based electrochemical biosensors/sensors, as the next generation of POC cancer screening tools, are summarized. Three cancer biomarker categories, including proteins, nucleic acids, and some small molecules, will be considered. Various 2D materials will be introduced and their biomedical applications and electrochemical properties will be given. The role of 2D materials in improving the performance of electrochemical sensing mechanisms as well as the pros and cons of current sensors as the prospective devices for POC screening will be emphasized. Finally, the future scopes of implementing 2D materials in electrochemical POC cancer diagnostics for the clinical translation will be discussed.