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Theranostics 2023There has been a long-standing interest in point-of-care (POC) diagnostics as a tool to improve patient care because it can provide rapid, actionable results near the... (Review)
Review
There has been a long-standing interest in point-of-care (POC) diagnostics as a tool to improve patient care because it can provide rapid, actionable results near the patient. Some of the successful examples of POC testing include lateral flow assays, urine dipsticks, and glucometers. Unfortunately, POC analysis is somewhat limited by the ability to manufacture simple devices to selectively measure disease specific biomarkers and the need for invasive biological sampling. Next generation POCs are being developed that make use of microfluidic devices to detect biomarkers in biological fluids in a non-invasive manner, addressing the above-mentioned limitations. Microfluidic devices are desirable because they can provide the ability to perform additional sample processing steps not available in existing commercial diagnostics. As a result, they can provide more sensitive and selective analysis. While most POC methods make use of blood or urine as a sample matrix, there has been a growing push to use saliva as a diagnostic medium. Saliva represents an ideal non-invasive biofluid for detecting biomarkers because it is readily available in large quantities and analyte levels reflect those in blood. However, using saliva in microfluidic devices for POC diagnostics is a relatively new and an emerging field. The overarching aim of this review is to provide an update on recent literature focused on the use of saliva as a biological sample matrix in microfluidic devices. We will first cover the characteristics of saliva as a sample medium and then review microfluidic devices that are developed for the analysis of salivary biomarkers.
Topics: Humans; Microfluidics; Point-of-Care Systems; Saliva; Point-of-Care Testing; Lab-On-A-Chip Devices; Biomarkers
PubMed: 36793864
DOI: 10.7150/thno.78872 -
Sensors (Basel, Switzerland) Jan 2023Telemedicine and digitalised healthcare have recently seen exponential growth, led, in part, by increasing efforts to improve patient flexibility and autonomy, as well... (Review)
Review
Telemedicine and digitalised healthcare have recently seen exponential growth, led, in part, by increasing efforts to improve patient flexibility and autonomy, as well as drivers from financial austerity and concerns over climate change. Nephrology is no exception, and daily innovations are underway to provide digitalised alternatives to current models of healthcare provision. Wearable technology already exists commercially, and advances in nanotechnology and miniaturisation mean interest is also garnering clinically. Here, we outline the current existing wearable technology pertaining to the diagnosis and monitoring of patients with a spectrum of kidney disease, give an overview of wearable dialysis technology, and explore wearables that do not yet exist but would be of great interest. Finally, we discuss challenges and potential pitfalls with utilising wearable technology and the factors associated with successful implementation.
Topics: Humans; Nephrology; Wearable Electronic Devices; Telemedicine; Delivery of Health Care; Biological Transport
PubMed: 36772401
DOI: 10.3390/s23031361 -
Journal of Medical Microbiology Feb 2023Urinary tract infection (UTI) is one of the most common bacterial infections among humans. Urine culture is the gold standard diagnostic method for UTI; however, the...
Urinary tract infection (UTI) is one of the most common bacterial infections among humans. Urine culture is the gold standard diagnostic method for UTI; however, the dipstick test for nitrite is a widely used method signalling the presence of urinary nitrate-reducing bacteria. Unlike the gold standard, the dipstick test is easy to perform, while it is also less time-consuming and less expensive, and produces a result in a few minutes. This study investigates the sensitivity of the dipstick test for nitrite compared with the Griess test in urine samples from UTI caused by species. We used the Griess test, which is the gold standard in nitrite measurement, to determine the sensitivity of the nitrite dipstick test. Semiquantitative urine culture was performed using standard procedures, and identification was performed by manual conventional biochemical tests. In the first sample selection, 3 % (8/267) of urine samples suspected of UTI, analysed from March to April 2016, were nitrite-negative by dipstick test but positive for in the urine culture. In the second sample selection, 5 % (2/44) of urine samples from October to December 2022 were also nitrite-negative but showed urine isolation. All nitrite-negative dipstick results were consistent with the Griess test. was the most prevalent bacterium, followed by independent of sample selection. The dipstick test is a safe alternative for investigating nitrite in urine samples. We believe that the cause of nitrite-negative results is a lack of dietary nitrate, dilution of urine and exogenous interference (e.g. ascorbic acid). These findings support the idea that standard urine culture is necessary to rule out UTI.
Topics: Humans; Nitrites; Nitrates; Negative Results; Sensitivity and Specificity; Reagent Strips; Urinary Tract Infections; Urinalysis; Escherichia coli
PubMed: 36762527
DOI: 10.1099/jmm.0.001663 -
Rinsho Biseibutsu Jinsoku Shindan... Dec 2022We compared rapid antigen detection kits widely used for the rapid diagnosis of group A streptococcal pharyngitis, evaluating their minimum detection sensitivity and...
We compared rapid antigen detection kits widely used for the rapid diagnosis of group A streptococcal pharyngitis, evaluating their minimum detection sensitivity and operability in five levels. Five kits based on the immunochromatographic method were used: ImunoAce Strep A (Tauns), ImunoAce Strep A Neo (Tauns), Quick Navi-StrepA2 (Denka), Quick Vue Dipstick Strep A (SB Bioscience) and RapidTesta Strep A (SEKISUI MEDICAL). Thirteen strains were tested: 10 clinical isolates of , 2 strains of subsp. (SDSE), and ATCC 19615. All kits had the same or higher minimum detection sensitivity than previously reported. ImunoAce StrepA Neo had the highest detection sensitivity and the best overall evaluation among the group A streptococcal rapid antigen detection kits used in this study. The detection sensitivity of SDSE with group A polysaccharide antigen was comparable to that of . Although culture tests are necessary to confirm the causative organism, SDSE may present with clinical symptoms similar to those of , and detection with a rapid antigen detection kit may be of therapeutic value.
Topics: Humans; Streptococcus pyogenes; Streptococcal Infections; Pharyngitis; Reagent Kits, Diagnostic
PubMed: 36560902
DOI: No ID Found -
Nephrologie & Therapeutique Dec 2022Peritoneal dialysis is the treatment of choice for end-stage renal disease. Peritoneal dialysis related peritonitis is of great importance for patient and technical...
Automated complete blood counter, urine analyzer and urine dipstick test results are correlated with thoma cell counting chamber counts in the diagnosis of dialysis related peritonitis in children.
INTRODUCTION
Peritoneal dialysis is the treatment of choice for end-stage renal disease. Peritoneal dialysis related peritonitis is of great importance for patient and technical survival. The aim of our study was to evaluate the accuracy and the correlation between the three methods (complete blood count, urinalysis device, urine dipstick test) and with the reference manual method (Thoma Cell Counter Chamber).
MATERIALS AND METHODS
We retrospectively analyzed 167 peritoneal fluid samples taken from 25 patients receiving peritoneal dialysis treatment. Leukocyte counts were evaluated with Thoma Cell Counter Chamber, complete blood count, urinalysis device and urine dipstick test.
RESULTS
There was a significant positive correlation between Thoma Cell Counter Chamber and complete blood count results (Spearman's rho=0.70), between Thoma Cell Counter Chamber and urinalysis device (Spearman's rho=0.73), and between Thoma Cell Counter Chamber and urine dipstick test (Spearman's rho=0.71). Area under curve for complete blood count, urinalysis device and urine dipstick test were 0.93, 0.94 and 0.89 respectively, indicating good accuracy. Sensitivity and specificity were 89.7% and 86.7% in the complete blood count analysis (associated criterion: 130 cells/mm). Sensitivity and specificity were 89.7% and 86.7% in the urinalysis device (associated criterion: 10 cells/HPF). Sensitivity and specificity were 79.6% and 91.4% when in the urine dipstick test analysis (associated criterion: +1 positivity). The Bland-Altman plot showed good agreement.
CONCLUSION
Automatic complete blood count and urinalysis devices have good correlation and agreement with manual method in the diagnosis of peritonitis in the pediatric age group. Urine dipstick test in the home setting can be useful for screening patients with suspected peritonitis.
Topics: Child; Humans; Retrospective Studies; Urinalysis; Peritonitis; Leukocyte Count; Sensitivity and Specificity
PubMed: 36435740
DOI: 10.1016/j.nephro.2022.10.001 -
Current Topics in Medicinal Chemistry Nov 2022The demand for point-of-care testing (POCT) devices has rapidly grown since they offer immediate test results with ease of use, makingthem suitable for home self-testing...
BACKGROUND
The demand for point-of-care testing (POCT) devices has rapidly grown since they offer immediate test results with ease of use, makingthem suitable for home self-testing patients and caretakers. However, the POCT development has faced the challenges of increased cost and limited resources. Therefore, the paper substrate as a low-cost material has been employed to develop a cost-effective POCT device, known as "Microfluidic paper-based analytical devices (μPADs)". This device is gaining attention as a promising tool for medicinal diagnostic applications owing to its unique features of simple fabrication, low cost, enabling manipulation flow (capillarydriven flow), the ability to store reagents, and accommodating multistep assay requirements.
OBJECTIVE
This review comprehensively examines the fabrication methods and device designs (2D/3D configuration) and their advantages and disadvantages, focusing on updated μPADs applications for motif identification.
METHODS
The evolution of paper-based devices, starting from the traditional devices of dipstick and lateral flow assay (LFA) with μPADs, has been described. Patterned structure fabrication of each technique has been compared among the equipment used, benefits, and drawbacks. Microfluidic device designs, including 2D and 3D configurations, have been introduced as well as their modifications. Various designs of μPADs have been integrated with many powerful detection methods such as colorimetry, electrochemistry, fluorescence, chemiluminescence, electrochemiluminescence, and SER-based sensors for medicinal diagnosis applications.
CONCLUSION
The μPADs potential to deal with commercialization in terms of the state-of-the-art of μPADs in medicinal diagnosis has been discussed. A great prototype, which is currently in a reallife application breakthrough, has been updated.
PubMed: 36330618
DOI: 10.2174/1568026623666221103103211 -
BMJ Open Oct 2022With advances in mobile technology, smartphone-based point-of-care testing (POCT) urinalysis hold great potential for disease screening and health management for...
OBJECTIVE
With advances in mobile technology, smartphone-based point-of-care testing (POCT) urinalysis hold great potential for disease screening and health management for clinicians and individual users. The purpose of this study is to evaluate the analytical performance of Hipee S2 POCT urine dipstick analyser.
DESIGN
A multicentre, hospital-based, cross-sectional study.
SETTING
Analytical performance of the POCT analyser was conducted at a clinical laboratory, and method comparison was performed at three clinical laboratories in China.
PARTICIPANTS
Urine samples were collected from 1603 outpatients and inpatients at three hospitals, and 5 health check-up population at one of the hospitals.
OUTCOME MEASURES
All tests were performed by clinical laboratory technicians. Precision, drift, carry-over, interference and method comparison of Hipee S2 were evaluated. Diagnostic accuracy of semiquantitative albumin-to-creatinine ratio (ACR) for albuminuria was carried out using quantitative ACR as the standard.
RESULTS
The precision for each parameter, assessed by control materials, was acceptable. No sample carry-over or drift was observed. Ascorbate solution with 1 g/L had an inhibitory effect for the haemoglobin test. Agreement for specific gravity (SG) varied between moderate to substantial (κ values 0.496-0.687), for pH was moderate (κ values 0.423-0.569) and for other parameters varied between substantial to excellent (κ values 0.669-0.991), on comparing the Hipee S2 with laboratory analysers. The semiquantitative microalbumin and creatinine were highly correlated with the quantitative results. The sensitivity of semiquantitative ACR to detect albuminuria was 87.2%-90.7%, specificity was 70.7%-78.4%, negative predictive value was 85.3%-87.9% and positive predictive value was 73.9%-83%.
CONCLUSIONS
Hipee S2 POCT urine analyser showed acceptable analytical performance as a semiquantitative method. It serves as a convenient alternate device for clinicians and individual users for urinalysis and health management. In addition, the POCT semiquantitative ACR would be useful in screening for albuminuria.
Topics: Humans; Albuminuria; Creatinine; Cross-Sectional Studies; Urinalysis; Point-of-Care Testing; Point-of-Care Systems
PubMed: 36302575
DOI: 10.1136/bmjopen-2022-063781 -
PLoS Neglected Tropical Diseases Oct 2022Urogenital schistosomiasis remains as a public health problem in Tanzania and for the past 15 years, mass drug administration (MDA) targeting primary school children has...
Urogenital schistosomiasis among pre-school and school aged children in four districts of north western Tanzania after 15 years of mass drug administration: Geographical prevalence, risk factors and performance of haematuria reagent strips.
BACKGROUND
Urogenital schistosomiasis remains as a public health problem in Tanzania and for the past 15 years, mass drug administration (MDA) targeting primary school children has remained as the mainstay for its control. However, after multiple rounds of MDA in highly risk groups, there are no data on the current status of Schistosoma haematobium in known endemic areas. Furthermore, the performance of commonly used diagnostic test, the urine reagent strips is not known after the decline in prevalence and intensities of infection following repeated rounds of treatment. Thus, after 15 of national MDA, there is a need to review the strategy and infection diagnostic tools available to inform the next stage of schistosomiasis control in the country.
METHODS/FINDINGS
A analytical cross-sectional study was conducted between October and November, 2019 among pre-school (3-5years old) and school aged children (6-17 years old) living in four (4) districts with low (<10%) and moderate (10%-<50%) endemicity for schistosomiasis as per WHO classification at the start of the national control programme in 2005/06, with mean prevalence of 20.7%. A total of 20,389 children from 88 randomly selected primary schools participated in the study. A questionnaire was used to record demographic information. A single urine sample was obtained from each participant and visually examined for macrohaematuria, tested with a dipstick for micro-haematuria, to determine blood in urine; a marker of schistosome related morbidity and a proxy of infection. Infection intensity was determined by parasitological examination of the urine sample for S. haematobium eggs. Overall, mean infection prevalence was 7.4% (95%CI: 7.0-7.7, 1514/20,389) and geometric mean infection intensity was 15.8eggs/10mls. Both infection prevalence (5.9% versus 9%, P<0.001) and intensity (t = -6.9256, P<0.001) were significantly higher in males compared to females respectively. Light and heavy infections were detected in 82.3% and 17.7% of the positive children respectively. The prevalence of macrohaematuria was 0.3% and that of microhaematuria was 9.3% (95%CI:8.9-9.7). The sensitivity and specificity of the urine reagent strip were 78% (95%CI: 76.1-79.9) and 99.8% (95%CI: 99.7-99.9). Having light (P<0.001) and heavy infection intensities (P<0.001) and living in the study districts increased the odd of having microhaematuria. Predictors of S. haematobium infection were being male (P<0.003), microhaematuria (P<0.001), and living in the three study districts (P<0.001) compared to living at Nzega district.
CONCLUSION
The findings provide an updated geographical prevalence which gives an insight on the planning and implementation of MDA. Comparing with the earlier mapping survey at the start of the national wide mass drug administration, the prevalence of S. haematobium infection have significantly declined. This partly could be attributed to repeated rounds of mass drug administration. The urine reagent strips remain as a useful adjunct diagnostic test for rapid monitoring of urogenital schistosomiasis in areas with low and high prevalence. Based on prevalence levels and with some schools having no detectable infections, review of the current blanket mass drug administration is recommended.
Topics: Child; Animals; Female; Child, Preschool; Humans; Male; Adolescent; Schistosomiasis haematobia; Reagent Strips; Hematuria; Mass Drug Administration; Prevalence; Cross-Sectional Studies; Tanzania; Schistosoma haematobium; Risk Factors
PubMed: 36223393
DOI: 10.1371/journal.pntd.0010834 -
Annual International Conference of the... Jul 2022A dipstick urinalysis test is performed by immersing a reagent strip in the urine specimen and then comparing the resulting reagent pad colors with a reference key. The...
A dipstick urinalysis test is performed by immersing a reagent strip in the urine specimen and then comparing the resulting reagent pad colors with a reference key. The color assessment of the reagent strip can be performed manually or by using a urine analyzer. However, the manual procedure is prone to subjective inaccuracies in varying ambient illumination and urine analyzer equipment is expensive. This paper presents a smartphone-based machine-learning approach to accurately determine the reagent pad colors for automated assessment. We start with a unique calibration chart and use multivariate linear regression to map the captured color values to their true equivalents. This accounts for the camera-induced distortions and ambient illumination factors. Subsequently, the color comparison is performed using the least Euclidean distance to match the calibrated color of each reagent pad with the reference key. The results from an experimental study, using five different smartphone cameras and three common illumination settings, indicate a high degree of accuracy in color assessment for synthetic dipsticks. The proposed smartphone-based method is an easy-to-perform, time-efficient, and cost-effective solution for an automated urinalysis and could be used as an alternative to manual reading or benchtop urine analyzers. Clinical Relevance- The methods, technology, and data reported in this research can serve as an accurate, reliable, and cost-effective means for automated urinalysis in comparison to the existing methods. Furthermore, the ubiquity of smartphones opens new avenues for automated diagnostics in clinical, at-home, and point-of-care settings.
Topics: Point-of-Care Systems; Reagent Strips; Smartphone; Urinalysis
PubMed: 36086074
DOI: 10.1109/EMBC48229.2022.9870917 -
Pregnancy Hypertension Dec 2022Preeclampsia and eclampsia contribute significantly to maternal and newborn deaths worldwide. Early and accurate identification of pregnant women at risk can avert these...
Evaluation of a protein-to-creatinine dipstick diagnostic test for proteinuria screening in selected antenatal care clinics in three Districts in the Bono-East Region of Ghana.
BACKGROUND
Preeclampsia and eclampsia contribute significantly to maternal and newborn deaths worldwide. Early and accurate identification of pregnant women at risk can avert these deaths, but the necessary diagnostics are not widely available. A protein and creatinine ratio, rather than a measurement of protein alone, may provide better identification of proteinuria. The objective of this study was to assess the operational and performance characteristics of the LifeAssay Diagnostics (LAD) Test-it™ protein-to-creatinine ratio (PrCr) urinalysis dipstick test in a representative antenatal care setting (ANC).
METHODS
Mixed methods were used to assess the operational and performance characteristics of the PrCr test, including a usability study with 25 participants, a prospective cross-sectional diagnostic accuracy study (N = 1483), and a targeted reassessment of discordant frozen samples (N = 200). Several other commonly used proteinuria tests were included for comparison.
RESULTS
The test demonstrated improved clinical performance for detection of proteinuria over the current standard-of-care tests widely used in Ghana. The LAD PrCr test showed a sensitivity of 50.7% and specificity of 69.2% when run at the point of care. In contrast, the standard-of-care Accu-Tell® protein dipstick test was found to have a sensitivity of 32.4% and a specificity of 82.2%. The LAD test shows minor improvement over the tests currently used in Ghana to detect proteinuria.
CONCLUSIONS
The PrCr test offers the potential for improved detection of proteinuria over the standard-of-care tests used in ANC. However, this test and the others evaluated for this study demonstrate limited performance, particularly among samples with a low level of proteinuria. Additional exploration in other clinical use cases, such as triage among high-risk populations, is warranted. The LAD test can also be considered a transition product, as health systems consider adopting next-generation biomarker tests when more readily available.
Topics: Infant, Newborn; Female; Pregnancy; Humans; Creatinine; Prenatal Care; Pre-Eclampsia; Prospective Studies; Diagnostic Tests, Routine; Cross-Sectional Studies; Ghana; Proteinuria; Urinalysis; Sensitivity and Specificity
PubMed: 35944384
DOI: 10.1016/j.preghy.2022.07.004