scholarly journals Clinical Validation of Rapid Gout Detection Method and Kit

2021 ◽  
Vol 4 (4) ◽  
pp. 69
Author(s):  
Amith Anugu ◽  
Rebecca Monastero ◽  
Sahana Pentyala ◽  
Vamiq M. Mustahsan ◽  
Yanming Cai ◽  
...  
Keyword(s):  
Uric Acid ◽  
Synovial Fluid ◽  
Silver Nitrate ◽  
Detection Method ◽  
Point Of Care ◽  
Colorimetric Method ◽  
Polarized Light ◽  
Clinical Samples ◽  
Fluid Analysis ◽  
Accessible Method

Gout is an inflammatory arthritis, which causes intense, acute pain due to the buildup of uric acid crystals in synovial fluid. The gold standard for gout diagnosis consists of synovial fluid analysis by polarized light microscopy, which is costly, time-intensive, and technique-dependent, therefore meriting a more efficient, inexpensive, and accessible method for diagnosis. We previously developed and validated a novel colorimetric gout detection method and device based on the reduction of silver nitrate by uric acid; here, we clinically validated our method and device using arthroscopically obtained synovial fluid samples from gout patients. We successfully identified uric acid crystals in clinical samples via our colorimetric method, visualized uric acid crystals in synovial fluid via handheld microscopy, and determined that silver nitrate stain did not interfere with the microscopic visualization of uric acid crystals necessary for diagnosis. We also developed and validated a method of processing turbid clinical samples for use in our device to prevent the obscuration of uric acid crystals by suspended material. Our method and device will clinically facilitate the immediate colorimetric diagnosis of gout and the subsequent bedside visualization of uric acid crystals in both ideal and turbid synovial fluid samples, allowing for a point-of-care diagnosis of gout.

scholarly journals Rapid Gout Detection Method and Kit

Diagnostics ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 157
Author(s):  
Srinivas Pentyala ◽  
Rebecca Monastero ◽  
Sai Palati ◽  
Elizabeth Varghese ◽  
Amith Anugu ◽  
...  
Keyword(s):  
Uric Acid ◽  
Synovial Fluid ◽  
Silver Nitrate ◽  
Colorimetric Method ◽  
The United States ◽  
Ease Of Use ◽  
Complex Method ◽  
Diagnostic Efficiency ◽  
Polarized Microscopy ◽  
Complex Procedure

Gout is a form of arthritis characterized by buildup of uric acid in synovial fluid, which causes severe swelling and can harm joints, tendons, and other tissues. It affects approximately 4% of the United States population, or approximately 8.3 million people nationwide and is therefore a topic of epidemiologic consideration due to its prevalence. Gout is typically diagnosed via polarized microscopy of arthroscopically-aspirated synovial fluid, which is a costly, time-consuming, labor-intensive, and technically complex procedure, warranting a simpler and less complex method for diagnosis. Here, we propose and validate a colorimetric method which is based on the ability of uric acid to reduce silver nitrate. We also assessed how the colorimetric change can be accelerated by changing the concentration of silver nitrate or adding different silver catalysts, as well as develop a matrix bed for improved handling and ease of use. When translated to the clinic, this diagnostic method for gout will have the potential to increase diagnostic efficiency and accelerate patient care at the bedside.

scholarly journals Articular and periarticular spinal calcifications in relation to synovial fluid findings in patients with calcium pyrophosphate dihydrate deposition disease (CPPD)

2021 ◽  
Vol 48 (1) ◽  
Author(s):  
Mohamed Ismail Abdelkareem ◽  
Abdou Saad Taha Ellabban ◽  
Ahmed Hamed Ismail ◽  
Mohamed Moneer Rayan ◽  
Rasha Ali Abdel-Magied
Keyword(s):  
Synovial Fluid ◽  
Light Microscopy ◽  
Polarized Light ◽  
Calcium Pyrophosphate ◽  
Plain Radiography ◽  
Polarized Light Microscopy ◽  
Calcium Pyrophosphate Dihydrate ◽  
Fluid Analysis ◽  
Deposition Disease ◽  
Synovial Fluid Analysis

Abstract Background Calcium pyrophosphate dihydrate deposition disease (CPPD) is the second most common form of the crystal-associated arthritis. Diagnosis is achieved by detection of crystals by polarized light microscopy and/or detection of hyaline cartilage or fibrocartilage calcifications characteristic of CPPD deposition by musculoskeletal ultrasound (MSUS). Axial involvement with intervertebral disc calcification, sacroiliac erosions, and sub-chondral cysts of the facet joints occurs with CPPD deposition. Aim To assess the presence and relation between calcification of intervertebral discs, other articular and periarticular spinal structures, and synovial fluid analysis (SFA) and MSUS calcifications in patients with CPPD deposition disease. Methods One hundred patients with CPPD disease diagnosed according to the modified proposed diagnostic criteria by McCarty 1994 were included. Plain radiography on the spines, pelvis, and affected joints, MSUS on affected joints, and synovial fluid analysis (SFA) were done. Results Spinal calcification was present in 55% of patients. The commonest site was anterior longitudinal ligament (43%). Characteristic CPPD calcifications by plain radiography on the knee and wrist joints were present in 38% and 16% respectively. Characteristic CPPD calcifications by MSUS on the knee and wrist joints presented in 93% and 27% respectively. CPPD crystal detection by SFA was 97%. The accuracy of MSUS to diagnose CPPD deposition disease is more than double that of plain radiography, and it is comparable to that of synovial fluid analysis. The result of intra-rater analysis between SFA by polarized light microscopy and MSUS was kappa 0.767 (p < 0.001); this indicates substantial level of agreement between SFA and MSUS; between plain radiography and MSUS, it was kappa 0.188 (p = 0.32) which indicates slight agreement, and between plain radiography and SFA, it was kappa 0.037 (p = 0.1) which fails to reach a significant level of agreement. There was a significant positive relation between spinal calcification and wrist joint calcification by plain radiography. Conclusion Considerable spinal affection by CPPD deposition disease can be detected. Although the most definitive, reliable direct approach for CPPD deposition disease diagnosis is SFA using polarized light microscopy, MSUS is considered a useful non-invasive diagnostic tool in this situation. In CPPD deposition disease, MSUS has proven to be an excellent technique for detecting calcification in the articular tissue disease compared to conventional radiography.

scholarly journals THU0406 IDENTIFICATION OF INTRACELLULAR VACUOLES IN SYNOVIAL FLUID WITH CALCIUM PYROPHOSPHATE AND MONOSODIUM URATE CRYSTALS

2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 440.1-441
Author(s):  
M. L. Peral ◽  
I. Calabuig ◽  
A. Martín-Carratalá ◽  
M. Andrés ◽  
E. Pascual
Keyword(s):  
Clinical Practice ◽  
Synovial Fluid ◽  
Phase Contrast ◽  
Calcium Pyrophosphate ◽  
Monosodium Urate ◽  
Fluid Analysis ◽  
Cytoplasmic Vacuoles ◽  
Contrast Microscopy ◽  
Ordinary Light ◽  
Msu Crystals

Background:Synovial fluid analysis using polarized microscopy is the gold standard for the diagnosis of crystal-related arthritis. In our experience, we have noted that, when calcium pyrophosphate (CPP) crystals are observed, they sometimes appear within intracellular vacuoles. However, this phenomenon is not seen in those samples containing monosodium urate (MSU) crystals. This finding has been scantly reported in the literature, but may be useful in clinical practice to ensure accurate crystal identification.Objectives:Our study aims to assess whether the presence of vacuoles contributes to identifying the type of crystal, and also to gauge the frequency of their presentation.Methods:We conducted an observational study in a rheumatology unit between February and June of 2019. Synovial fluids containing CPP or MSU crystals, obtained in daily clinical practice, were consecutively included for analysis. Two observers simultaneously analyzed the presence of vacuoles by ordinary light and phase contrast microscopy in less than 24 hours after their extraction, using a microscope equipped with two viewing stations. The primary study variable was to determine whether CPP and MSU crystals are seen inside intracellular vacuoles, and to calculate the frequency of this finding for each type of crystal, estimating their 95% confidence interval (95% CI) and comparing rates using Fisher’s exact test.Results:Twenty-one samples were obtained. Data is given in the Table. MSU crystals were present in 7 (33.3%) and CPP crystals in 14 (66.6%). Interestingly, none of the MSU samples showed crystal-containing vacuoles (95% CI 0-35.4%). On the contrary, cytoplasmic vacuoles containing crystals were present in all of the CPP samples (95% CI 78.5-100%). The findings were confirmed by phase-contrast microscopy. Differences were statistically significant (p<0.001).Table.SAMPLES ACCORDING TO TYPE OF MICROCRYSTAL(n=21)SAMPLES WITH VACUOLS(UNDER ORDINARY LIGHT)SAMPLES WITH VACUOLS(UNDER PHASE CONTRAST)CPP (14; 66.6%)14 (100%)(95%CI 78.5-100%)14 (100%)(95%CI 78.5-100%)MSU (7; 33.3%)0 (0%)(95%CI 0-35.4%)0 (0%)(95%CI 0-35.4%)Conclusion:The presence of vacuoles may be a useful and easy way to differentiate MSU and CPP crystals when performing synovial fluid microscopy in clinical practice, since it appears to be a distinctive feature in CPP crystal fluids.References:[1]Kohn NN, Hughes RE, McCarty DJ Jr, Faires JS. The significance of calcium phosphate crystals in the synovial fluid of arthritic patients: the «pseudogout syndrome». II. Identification of crystals. Ann InternMed. 1962 May;56:738-45.[2]Pascual E, Sivera F, Andrés M. Synovial Fluid Analysis for Crystals. CurrOpRheumatol 2011;23:161-169.[3]McCarty DJ, Koopman WJ. Arthritis and allied conditions: A textbook of rheumatology, volumen 1. Lea &amp;Febiger. 1993.[4]Pascual E, Sivera F. Synovial fluid crystal Analysis. En Gout and other crystal arthropathies. Terkeltaub R ed. Elsevier; 2012: p.20-34.[5]Hwang HS, Yang CM, Park SJ, Kim HA. Monosodium Urate Crystal-Induced Chondrocyte Death via Autophagic Process. Int J Mol Sci. 2015 Dec 8;16(12):29265-77.Image 1. Microscopy with ordinary light. Cells with cytoplasmic vacuoles are observed, as well as abundant intra and extracellular CPP crystals.Image 2. Microscopy with phase contrast technique. Cells with intracellular vacuoles are observed inside which have microcrystals with parallelepiped morphology, compatible with CPP.Disclosure of Interests: :None declared

scholarly journals AB0629 ACCURACY OF SYNOVIAL FLUID ANALYSIS FOR THE IDENTIFICATION OF CALCIUM PYROPHOSPHATE CRYSTALS: AN ANCILLARY STUDY OF OMERACT CRITERION VALIDITY STUDY FOR ULTRASOUND IN CPPD

2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 1348.1-1348
Author(s):  
A. Adinolfi ◽  
S. Sirotti ◽  
M. Gutierrez ◽  
C. Pineda ◽  
D. Clavijo Cornejo ◽  
...  
Keyword(s):  
Synovial Fluid ◽  
Diagnostic Accuracy ◽  
Light Microscopy ◽  
Hyaline Cartilage ◽  
Microscopic Analysis ◽  
Calcium Pyrophosphate ◽  
Ancillary Study ◽  
Fluid Analysis ◽  
Synovial Fluid Analysis ◽  
Sensitivity Specificity

Background:Synovial fluid analysis (SFA) via compensated polarized light microscopy is still considered the gold standard for the identification and diagnosis of Calcium Pyrophosphate Deposition disease (CPPD)-related arthropathies[1], but very few studies have been published about its diagnostic accuracy.Objectives:The aim of this study was to evaluate the accuracy of SFA in the identification of calcium pyrophosphate dihydrate (CPP) crystals compared to microscopic analysis of joint tissues as the reference standard.Methods:This is an ancillary study of an international, multicentre cross-sectional study performed by the CPPD subgroup of the OMERACT Ultrasound working group[2]. Consecutive patients with knee osteoarthritis (OA) waiting for total knee replacement surgery were enrolled in the study from 2 participating centres, Mexico and Romania. During surgical procedures synovial fluid (SF), menisci and hyaline cartilage were collected and analysed within 48 hours after surgery under transmitted light microscopy and compensated polarised light microscopy for the presence/absence of CPP crystals. All slides were analysed by expert examiners on site, blinded to other findings. A dichotomic score (absence/presence) was used for scoring both SF and tissues. Microscopic analysis of knee tissues was considered the gold standard. Sensitivity, specificity, accuracy, positive and negative predictive values (PPV and NPV) of SFA in the identification of CPP crystals were calculated.Results:15 patients (53% female, mean age 68yo ± 8.4) with OA of grade 3 or 4 according to Kellgren-Lawrence scoring were enrolled. 12 patients (80%) were positive for CPP crystals at SFA and 14 (93%) at tissues microscopic analysis. Among 12 SFA positive patients, all were positive for CPP crystals in either medial or lateral meniscus, and 11 were positive in both; 10 patients were positive at the hyaline cartilage, and all 10 were also positive for at least one meniscus. Regarding the 3 SFA negative patients, only one had no crystals in the examined tissues, while the other 2 patients had CPP crystals in both menisci and hyaline cartilage. The overall diagnostic accuracy of SFA compared to histology analysis for CPPD was 87%, with a sensitivity of 86% and a specificity of 100%, the PPV was 100% and the NPV was 33% (Table 1).Table 1.sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and diagnostic accuracy of synovial fluid analysis compared to the reference standard. CI: Confidential Interval. SF: synovial fluid, in parentheses: numerators and denominators for all percentages provided.SensitivitySpecificityPPVNPVAccuracySF analysis86% (12/14)100% (1/1)100% (12/12)33% (1/3)87% (13/15)(0.65-0.99) CI 95%(0.0-0.25) CI 95%(0.65-0.99) CI 95%(0.0-0.25) CI 95%Conclusion:SFA demonstrated to be an accurate test for the identification of CPP crystals in patients with advanced OA. However, is not always feasible and carries some risks for the patient. Considering the availability of validated imaging techniques for the detection of CPPD, such as US, SFA could be used in those patients where imaging and clinical data are not definitely confirmatory of the disease.References:[1]W. Zhang et al., ‘European League Against Rheumatism recommendations for calcium pyrophosphate deposition. Part I: terminology and diagnosis’, Ann Rheum Dis, vol. 70, no. 4, pp. 563–570, Apr. 2011, doi: 10.1136/ard.2010.139105.[2]G. Filippou et al., ‘Criterion validity of ultrasound in the identification of calcium pyrophosphate crystal deposits at the knee: an OMERACT ultrasound study’, Ann Rheum Dis, p. annrheumdis-2020-217998, Sep. 2020, doi: 10.1136/annrheumdis-2020-217998.Disclosure of Interests:None declared.

Clinical assessment of the Roche SARS-CoV-2 rapid antigen test

Diagnosis ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Gian Luca Salvagno ◽  
Gianluca Gianfilippi ◽  
Damiano Bragantini ◽  
Brandon M. Henry ◽  
Giuseppe Lippi
Keyword(s):  
Clinical Assessment ◽  
Clinical Performance ◽  
Point Of Care ◽  
High Viral Load ◽  
Rapid Screening ◽  
Clinical Samples ◽  
Molecular Testing ◽  
Antigen Test ◽  
Community Screening ◽  
Final Study

Abstract Objectives Novel point-of-care antigen assays present a promising opportunity for rapid screening of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. The purpose of this study was the clinical assessment of the new Roche SARS-CoV-2 Rapid Antigen Test. Methods The clinical performance of Roche SARS-CoV-2 Rapid Antigen Test was evaluated vs. a reverse transcription polymerase chain reaction (RT-PCR) laboratory-based assay (Seegene AllplexTM2019-nCoV) in nasopharyngeal swabs collected from a series of consecutive patients referred for SARS-CoV-2 diagnostics to the Pederzoli Hospital (Peschiera del Garda, Verona, Italy) over a 2-week period. Results The final study population consisted of 321 consecutive patients (mean age, 46 years and IQR, 32–56 years; 181 women, 56.4%), with 149/321 (46.4%) positive for SARS-CoV-2 RNA via the Seegene AllplexTM2019-nCoV Assay, and 109/321 (34.0%) positive with Roche SARS-CoV-2 Rapid Antigen Test, respectively. The overall accuracy of Roche SARS-CoV-2 Rapid Antigen Test compared to molecular testing was 86.9%, with 72.5% sensitivity and 99.4% specificity. Progressive decline in performance was observed as cycle threshold (Ct) values of different SARS-CoV-2 gene targets increased. The sensitivity was found to range between 97–100% in clinical samples with Ct values <25, between 50–81% in those with Ct values between 25 and <30, but low as 12–18% in samples with Ct values between 30 and <37. Conclusions The clinical performance of Roche SARS-CoV-2 Rapid Antigen Test is excellent in nasopharyngeal swabs with Ct values <25, which makes it a reliable screening test in patients with high viral load. However, mass community screening would require the use of more sensitive techniques.

scholarly journals Direct diagnostic testing of SARS-CoV-2 without the need for prior RNA extraction

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Shan Wei ◽  
Esther Kohl ◽  
Alexandre Djandji ◽  
Stephanie Morgan ◽  
Susan Whittier ◽  
...  
Keyword(s):  
Limit Of Detection ◽  
Point Of Care ◽  
Diagnostic Testing ◽  
Rna Extraction ◽  
Cost Effective ◽  
Clinical Samples ◽  
Nasopharyngeal Swab ◽  
Percentage Agreement ◽  
Testing Method ◽  
Viral Transport

AbstractThe COVID-19 pandemic has resulted in an urgent need for a rapid, point of care diagnostic testing that could be rapidly scaled on a worldwide level. We developed and tested a highly sensitive and robust assay based on reverse transcription loop mediated isothermal amplification (RT-LAMP) that uses readily available reagents and a simple heat block using contrived spike-in and actual clinical samples. RT-LAMP testing on RNA-spiked samples showed a limit of detection (LoD) of 2.5 copies/μl of viral transport media. RT-LAMP testing directly on clinical nasopharyngeal swab samples in viral transport media had an 85% positive percentage agreement (PPA) (17/20), and 100% negative percentage agreement (NPV) and delivered results in 30 min. Our optimized RT-LAMP based testing method is a scalable system that is sufficiently sensitive and robust to test for SARS-CoV-2 directly on clinical nasopharyngeal swab samples in viral transport media in 30 min at the point of care without the need for specialized or proprietary equipment or reagents. This cost-effective and efficient one-step testing method can be readily available for COVID-19 testing world-wide, especially in resource poor settings.

scholarly journals Essential properties and pitfalls of colorimetric Reverse Transcription Loop-mediated Isothermal Amplification as a point-of-care test for SARS-CoV-2 diagnosis

2021 ◽  
Vol 27 (1) ◽  
Author(s):  
Bruna de Oliveira Coelho ◽  
Heloisa Bruna Soligo Sanchuki ◽  
Dalila Luciola Zanette ◽  
Jeanine Marie Nardin ◽  
Hugo Manuel Paz Morales ◽  
...  
Keyword(s):  
Viral Load ◽  
Internal Control ◽  
Reverse Transcription ◽  
Color Change ◽  
Point Of Care ◽  
Colorimetric Detection ◽  
False Negative ◽  
Isothermal Amplification ◽  
Clinical Samples ◽  
Loop Mediated Isothermal Amplification

Abstract Background SARS-CoV-2 Reverse Transcription Loop-mediated Isothermal Amplification (RT-LAMP) colorimetric detection is a sensitive and specific point-of-care molecular biology technique used to detect the virus in only 30 min. In this manuscript we have described a few nuances of the technique still not properly described in the literature: the presence of three colors clusters; the correlation of the viral load with the color change; and the importance of using an internal control to avoid false-negative results. Methods To achieve these findings, we performed colorimetric RT-LAMP assays of 466 SARS-CoV-2 RT-qPCR validated clinical samples, with color quantification measured at 434 nm and 560 nm. Results First we determinate a sensitivity of 93.8% and specificity of 90.4%. In addition to the pink (negative) and yellow (positive) produced colors, we report for the first time the presence of an orange color cluster that may lead to wrong diagnosis. We also demonstrated using RT-qPCR and RT-LAMP that low viral loads are related to Ct values > 30, resulting in orange colors. We also demonstrated that the diagnosis of COVID-19 by colorimetric RT-LAMP is efficient until the fifth symptoms day when the viral load is still relatively high. Conclusion This study reports properties and indications for colorimetric RT-LAMP as point-of-care for SARS-CoV-2 diagnostic, reducing false results, interpretations and optimizing molecular diagnostics tests application.

scholarly journals Evaluation of mobile real-time polymerase chain reaction tests for the detection of severe acute respiratory syndrome coronavirus 2

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Chukwunonso Onyilagha ◽  
Henna Mistry ◽  
Peter Marszal ◽  
Mathieu Pinette ◽  
Darwyn Kobasa ◽  
...  
Keyword(s):  
Severe Acute Respiratory Syndrome ◽  
Real Time ◽  
Point Of Care ◽  
Middle Eastern ◽  
Turnaround Time ◽  
Cross Reactivity ◽  
Clinical Samples ◽  
Diarrhea Virus ◽  
Highly Sensitive ◽  
Transmissible Gastroenteritis

AbstractThe coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), calls for prompt and accurate diagnosis and rapid turnaround time for test results to limit transmission. Here, we evaluated two independent molecular assays, the Biomeme SARS-CoV-2 test, and the Precision Biomonitoring TripleLock SARS-CoV-2 test on a field-deployable point-of-care real-time PCR instrument, Franklin three9, in combination with Biomeme M1 Sample Prep Cartridge Kit for RNA 2.0 (M1) manual extraction system for rapid, specific, and sensitive detection of SARS-COV-2 in cell culture, human, and animal clinical samples. The Biomeme SARS-CoV-2 assay, which simultaneously detects two viral targets, the orf1ab and S genes, and the Precision Biomonitoring TripleLock SARS-CoV-2 assay that targets the 5′ untranslated region (5′ UTR) and the envelope (E) gene of SARS-CoV-2 were highly sensitive and detected as low as 15 SARS-CoV-2 genome copies per reaction. In addition, the two assays were specific and showed no cross-reactivity with Middle Eastern respiratory syndrome coronavirus (MERS-CoV), infectious bronchitis virus (IBV), porcine epidemic diarrhea virus (PEDV), transmissible gastroenteritis (TGE) virus, and other common human respiratory viruses and bacterial pathogens. Also, both assays were highly reproducible across different operators and instruments. When used to test animal samples, both assays equally detected SARS-CoV-2 genetic materials in the swabs from SARS-CoV-2-infected hamsters. The M1 lysis buffer completely inactivated SARS-CoV-2 within 10 min at room temperature enabling safe handling of clinical samples. Collectively, these results show that the Biomeme and Precision Biomonitoring TripleLock SARS-CoV-2 mobile testing platforms could reliably and promptly detect SARS-CoV-2 in both human and animal clinical samples in approximately an hour and can be used in remote areas or health care settings not traditionally serviced by a microbiology laboratory.

A pragmatic eLCR for an ultrasensitive detection of methicillin-resistant Staphylococcus aureus in joint synovial fluid: superior to qPCR

The Analyst ◽  
2021 ◽  
Author(s):  
Jinyuan Chen ◽  
Hongxiang Wei ◽  
Xinyu Fang ◽  
Yuanqing Cai ◽  
Zhenzhen Zhang ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Synovial Fluid ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Detection Method ◽  
Low Cost ◽  
Ultrasensitive Detection ◽  
Gene Detection ◽  
Methicillin Resistant ◽  
Cost Identification

A pragmatic electrochemical mecA gene detection method for a rapid, accurate and low-cost identification of MRSA in the joint synovial fluid of PJI patients.

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