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Annals of Internal Medicine Sep 2020Although measuring albuminuria is the preferred method for defining and staging chronic kidney disease (CKD), total urine protein or dipstick protein is often measured... (Meta-Analysis)
Meta-Analysis
Conversion of Urine Protein-Creatinine Ratio or Urine Dipstick Protein to Urine Albumin-Creatinine Ratio for Use in Chronic Kidney Disease Screening and Prognosis : An Individual Participant-Based Meta-analysis.
BACKGROUND
Although measuring albuminuria is the preferred method for defining and staging chronic kidney disease (CKD), total urine protein or dipstick protein is often measured instead.
OBJECTIVE
To develop equations for converting urine protein-creatinine ratio (PCR) and dipstick protein to urine albumin-creatinine ratio (ACR) and to test their diagnostic accuracy in CKD screening and staging.
DESIGN
Individual participant-based meta-analysis.
SETTING
12 research and 21 clinical cohorts.
PARTICIPANTS
919 383 adults with same-day measures of ACR and PCR or dipstick protein.
MEASUREMENTS
Equations to convert urine PCR and dipstick protein to ACR were developed and tested for purposes of CKD screening (ACR ≥30 mg/g) and staging (stage A2: ACR of 30 to 299 mg/g; stage A3: ACR ≥300 mg/g).
RESULTS
Median ACR was 14 mg/g (25th to 75th percentile of cohorts, 5 to 25 mg/g). The association between PCR and ACR was inconsistent for PCR values less than 50 mg/g. For higher PCR values, the PCR conversion equations demonstrated moderate sensitivity (91%, 75%, and 87%) and specificity (87%, 89%, and 98%) for screening (ACR >30 mg/g) and classification into stages A2 and A3, respectively. Urine dipstick categories of trace or greater, trace to +, and ++ for screening for ACR values greater than 30 mg/g and classification into stages A2 and A3, respectively, had moderate sensitivity (62%, 36%, and 78%) and high specificity (88%, 88%, and 98%). For individual risk prediction, the estimated 2-year 4-variable kidney failure risk equation using predicted ACR from PCR had discrimination similar to that of using observed ACR.
LIMITATION
Diverse methods of ACR and PCR quantification were used; measurements were not always performed in the same urine sample.
CONCLUSION
Urine ACR is the preferred measure of albuminuria; however, if ACR is not available, predicted ACR from PCR or urine dipstick protein may help in CKD screening, staging, and prognosis.
PRIMARY FUNDING SOURCE
National Institute of Diabetes and Digestive and Kidney Diseases and National Kidney Foundation.
Topics: Albuminuria; Creatinine; Female; Humans; Male; Mass Screening; Middle Aged; Prognosis; Proteinuria; Reagent Strips; Renal Insufficiency, Chronic; Sensitivity and Specificity; Urinalysis
PubMed: 32658569
DOI: 10.7326/M20-0529 -
American Family Physician Dec 2012Cutaneous cryosurgery refers to localized application of freezing temperatures to achieve destruction of skin lesions. It can be used to treat a broad range of benign...
Cutaneous cryosurgery refers to localized application of freezing temperatures to achieve destruction of skin lesions. It can be used to treat a broad range of benign and premalignant skin conditions, and certain malignant skin conditions, with high cure rates. Cellular destruction is accomplished by delivery of the cryogen via dipstick, probe, or spray techniques. It is widely used in primary care because of its safety, effectiveness, low cost, ease of use, good cosmetic results, and lack of need for anesthesia. Cryosurgery is as effective as alternative therapies for most cases of molluscum contagiosum, dermatofibromas, keloids, and plantar or genital warts. It is a more effective cure for common warts than salicylic acid or observation. Cryosurgery is generally the treatment of choice for actinic keratosis. Contraindications to cryosurgery include cryofibrinogenemia, cryoglobulinemia, Raynaud disease, agammaglobulinemia, and multiple myeloma. Complications from cryosurgery include hypopigmentation and alopecia, and can be avoided by limiting freeze times to less than 30 seconds. Referral to a dermatologist should be considered in cases of diagnostic uncertainty or for treatment of skin cancer, which requires larger amounts of tissue destruction, resulting in higher complication rates.
Topics: Condylomata Acuminata; Cryosurgery; Histiocytoma, Benign Fibrous; Humans; Keloid; Keratosis, Actinic; Molluscum Contagiosum; Practice Guidelines as Topic; Skin Diseases; Skin Neoplasms; Treatment Outcome; United States; Warts; Wound Healing
PubMed: 23316984
DOI: No ID Found -
Sensors (Basel, Switzerland) Apr 2022Cancer is a major cause of mortality and morbidity worldwide. Detection and quantification of cancer biomarkers plays a critical role in cancer early diagnosis,... (Review)
Review
Cancer is a major cause of mortality and morbidity worldwide. Detection and quantification of cancer biomarkers plays a critical role in cancer early diagnosis, screening, and treatment. Clinicians, particularly in developing countries, deal with high costs and limited resources for diagnostic systems. Using low-cost substrates to develop sensor devices could be very helpful. The interest in paper-based sensors with colorimetric detection increased exponentially in the last decade as they meet the criteria for point-of-care (PoC) devices. Cellulose and different nanomaterials have been used as substrate and colorimetric probes, respectively, for these types of devices in their different designs as spot tests, lateral-flow assays, dipsticks, and microfluidic paper-based devices (μPADs), offering low-cost and disposable devices. However, the main challenge with these devices is their low sensitivity and lack of efficiency in performing quantitative measurements. This review includes an overview of the use of paper for the development of sensing devices focusing on colorimetric detection and their application to cancer biomarkers. We highlight recent works reporting the use of paper in the development of colorimetric sensors for cancer biomarkers, such as proteins, nucleic acids, and others. Finally, we discuss the main advantages of these types of devices and highlight their major pitfalls.
Topics: Biomarkers; Biomarkers, Tumor; Colorimetry; Lab-On-A-Chip Devices; Microfluidic Analytical Techniques; Neoplasms; Paper; Point-of-Care Systems
PubMed: 35590912
DOI: 10.3390/s22093221 -
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 -
Sensors (Basel, Switzerland) Jan 2019Paper-based sensors and assays have been highly attractive for numerous biological applications, including rapid diagnostics and assays for disease detection, food... (Review)
Review
Paper-based sensors and assays have been highly attractive for numerous biological applications, including rapid diagnostics and assays for disease detection, food safety, and clinical care. In particular, the paper immunoassay has helped drive many applications in global health due to its low cost and simplicity of operation. This review is aimed at examining the fundamentals of the technology, as well as different implementations of paper-based assays and discuss novel strategies for improving their sensitivity, performance, or enabling new capabilities. These innovations can be categorized into using unique nanoparticle materials and structures for detection via different techniques, novel biological species for recognizing biomarkers, or innovative device design and/or architecture.
Topics: Biomarkers; Biosensing Techniques; Humans; Immunoassay; Nanoparticles; Paper
PubMed: 30699964
DOI: 10.3390/s19030554 -
Molecules (Basel, Switzerland) Jan 2022Paper-based analytical devices (PADs), including lateral flow assays (LFAs), dipstick assays and microfluidic PADs (μPADs), have a great impact on the healthcare realm... (Review)
Review
Paper-based analytical devices (PADs), including lateral flow assays (LFAs), dipstick assays and microfluidic PADs (μPADs), have a great impact on the healthcare realm and environmental monitoring. This is especially evident in developing countries because PADs-based point-of-care testing (POCT) enables to rapidly determine various (bio)chemical analytes in a miniaturized, cost-effective and user-friendly manner. Low sensitivity and poor specificity are the main bottlenecks associated with PADs, which limit the entry of PADs into the real-life applications. The application of nanomaterials in PADs is showing great improvement in their detection performance in terms of sensitivity, selectivity and accuracy since the nanomaterials have unique physicochemical properties. In this review, the research progress on the nanomaterial-based PADs is summarized by highlighting representative recent publications. We mainly focus on the detection principles, the sensing mechanisms of how they work and applications in disease diagnosis, environmental monitoring and food safety management. In addition, the limitations and challenges associated with the development of nanomaterial-based PADs are discussed, and further directions in this research field are proposed.
Topics: Biological Assay; Diagnostic Tests, Routine; Humans; Microfluidic Analytical Techniques; Nanostructures; Paper; Point-of-Care Testing
PubMed: 35056823
DOI: 10.3390/molecules27020508 -
Expert Review of Molecular Diagnostics Jan 2020: The development of point-of-care testing (POCT) has made clinical diagnostics available, affordable, rapid, and easy to use since the 1990s.The significance of this... (Review)
Review
: The development of point-of-care testing (POCT) has made clinical diagnostics available, affordable, rapid, and easy to use since the 1990s.The significance of this platform rests on its potential to empower patients to monitor their own health status more frequently, in the convenience of their home, so that diseases can be diagnosed at the earliest possible time-point. Recent advances have expanded traditional formats such as qualitative or semi-quantitative dipsticks and lateral flow immunoassays to newer platforms such as microfluidics and paper-based assays where signals can be measured quantitatively using handheld devices.: This review discusses: (1) working principles and operating mechanisms of both existing and emerging POCT platforms, (2) urine analytes measured using POCT in comparison to the laboratory or clinical 'gold standard,' and (3) limitations of existing POCT and expectations of emerging POCT in urinalysis.: Currently, a variety of biological samples such as urine, saliva, serum, plasma, and other fluids can be applied to POCT for quick diagnosis, especially in resource-limited settings. Emerging platforms will increasingly empower individuals to monitor their health status through frequent urine analysis even from their homes. The impact of these emerging technologies on healthcare is likely to be transformative.
Topics: Humans; Immunoassay; Microfluidics; Molecular Diagnostic Techniques; Point-of-Care Systems; Urinalysis
PubMed: 31795785
DOI: 10.1080/14737159.2020.1699063