scholarly journals Evaluation of an Aspergillus IgG/IgM lateral flow assay for serodiagnosis of fungal asthma in Uganda

PLoS ONE ◽  
2021 ◽  
Vol 16 (5) ◽  
pp. e0252553
Author(s):  
Richard Kwizera ◽  
Felix Bongomin ◽  
Ronald Olum ◽  
William Worodria ◽  
Freddie Bwanga ◽  
...  
Keyword(s):  
Severe Asthma ◽  
Predictive Value ◽  
Point Of Care ◽  
Allergic Bronchopulmonary Aspergillosis ◽  
Specific Ige ◽  
Lateral Flow ◽  
Control Group ◽  
Middle Income ◽  
Middle Income Countries ◽  
Sensitivity Specificity

Background Diagnosis of fungal allergies in asthma remains problematic in low-and middle-income countries due to non-availability of point-of-care testing. In this study, we aimed to evaluate the performance of an Aspergillus immunochromatographic technology (ICT) IgG/M lateral flow device (LFD) for the serological diagnosis of allergic bronchopulmonary aspergillosis (ABPA) and severe asthma with fungal sensitisation (SAFS) among Ugandan adult asthmatics. Methods 374 adult (aged ≥18years) asthmatics in the African Severe Asthma Program study, Ugandan site constituted the study population. ABPA and SAFS were diagnosed according to standard criteria. Asthmatics who did not meet the above criteria constituted a control group. The LFD tests were performed and read according to manufacturer’s instructions. Results ABPA was found in 12/374 (3.2%) and SAFS in 60/374 (16%) participants. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for the Aspergillus ICT for the diagnosis of ABPA were 0.0%, 96.4%, 0.0% and 96.7% respectively, and for SAFS 6.7%, 97.1%, 30.8% and 84.5% respectively. False positive and negative rates were 3.5% and 3.2% for ABPA and 2.4% and 14.9% for SAFS, respectively. Patients with a positive LFD significantly had higher median Aspergillus fumigatus-specific IgE levels compared to those with negative LFD (median: 0.06 kUA/l VS 0.03 kUA/L, P = 0.011). Conclusion The Aspergillus ICT IgG/M LFD had a poor diagnostic performance for the diagnosis of both ABPA and SAFS. Its greatest value may be in distinguishing chronic and allergic aspergillosis in Africa.

scholarly journals Evaluation of Production Lots of a Rapid Point-of-Care Lateral Flow Serological Test Intended for Identification of IgM and IgG against the N-Terminal Part of the Spike Protein (S1) of SARS-CoV-2

Viruses ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1043
Author(s):  
Tove Hoffman ◽  
Linda Kolstad ◽  
Bengt Rönnberg ◽  
Åke Lundkvist
Keyword(s):  
Predictive Value ◽  
Serological Test ◽  
Point Of Care ◽  
External Validation ◽  
High Sensitivity ◽  
Lateral Flow ◽  
Spike Protein ◽  
Individual Level ◽  
Lateral Flow Test ◽  
Production Errors

The potential of rapid point-of-care (POC) tests has been subject of doubt due to an eventual risk of production errors. The aim was therefore to evaluate the two separate production lots of a commercial POC lateral flow test, intended for the detection of IgM and IgG against the SARS-CoV-2 spike protein (S1). Control samples consisted of serum from individuals with confirmed SARS-CoV-2 infection and pre-COVID-19 negative sera gathered from a biobank. The presence of anti-S1 IgM/IgG in the sera was verified by an in-house Luminex-based serological assay (COVID-19 SIA). One hundred samples were verified as positive for anti-S1 IgG and 74 for anti-S1 IgM. Two hundred samples were verified as negative for anti-S1 IgM/IgG. For the two lots of the POC-test, the sensitivities were 93.2% and 87.8% for IgM and 93.0% and 100% for IgG. The specificities were 100% for IgM and 99.5% for IgG. The positive predictive value was 100% for IgM and 98.9% and 99.0% for IgG. The negative predictive value was 97.6% and 95.7% for IgM, and 96.6% and 100% for IgG. The evaluated POC-test is suitable to assess anti-SARS-CoV-2 S1 IgM and IgG, as a measure of previous virus exposure on an individual level. The external validation of separate lots of rapid POC-tests is encouraged to ensure high sensitivity before market introduction.

scholarly journals Validation of the SavvyCheckTM Vaginal Yeast Test for Screening Pregnant Women for Vulvovaginal Candidosis: A Prospective, Cross-Sectional Study

2021 ◽  
Vol 7 (3) ◽  
pp. 233
Author(s):  
Philipp Foessleitner ◽  
Herbert Kiss ◽  
Julia Deinsberger ◽  
Julia Ott ◽  
Lorenz Zierhut ◽  
...  
Keyword(s):  
Pregnant Women ◽  
Predictive Value ◽  
Point Of Care ◽  
Cross Sectional Study ◽  
Control Group ◽  
Gram Stain ◽  
Cross Sectional ◽  
Point Of Care Test ◽  
Increased Risk ◽  
Vulvovaginal Candidosis

Pregnant women have an increased risk of vulvovaginal candidosis. Recurrent candidosis is under debate as a contributor to preterm birth, and vertical transmission may cause diaper dermatitis and oral thrush in the newborn. Apart from cultural methods, the gold standard for diagnosing candidosis is Gram staining, which is time-consuming and requires laboratory facilities. The objective of this prospective study was to validate a point-of-care vaginal yeast detection assay (SavvyCheckÔ Vaginal Yeast Test) and to evaluate it in asymptomatic pregnant women. We enrolled 200 participants, 100 of whom had vulvovaginal candidosis according to Gram stain (study group) and 100 were healthy pregnant controls (control group). Of these, 22 participants (11%) had invalid test results. The point-of-care test of the remaining 85 and 93 study participants in the study and control groups, respectively, showed a sensitivity of 94.1%, specificity of 98.9%, positive predictive value of 90.3%, and negative predictive value of 99.4% when compared with Gram stain. In conclusion, we found a high correlation between the SavvyCheckÔ Vaginal Yeast Test and Gram-stained smears during pregnancy. This suggests a potential role of this point-of-care test as a screening tool for asymptomatic pregnant women in early gestation.

scholarly journals Using pictorial action instructions to build a basic humanitarian engineering project

2019 ◽  
Vol 14 (1) ◽  
pp. 60-70
Author(s):  
Kathleen Paco Cadman ◽  
Du Feng
Keyword(s):  
Self Efficacy ◽  
Intervention Group ◽  
Control Group ◽  
Low Literacy ◽  
Engineering Project ◽  
Middle Income ◽  
Middle Income Countries ◽  
Humanitarian Engineering ◽  
Engineering Projects ◽  
Low And Middle Income

Humanitarian engineering projects mitigate environmental hazards disproportionately affecting health in low- and middle-income countries. However, widespread literacy deficits can create barriers in training low-literacy adults to construct these projects, indicating a need for literacy-adapted training materials. A randomized control trial in rural Guatemala tested the usability of pictorial action instructions, compared to demonstration-only methods, in training low-literacy adults (N = 60; n = 30 per group) to construct a solar bottle bulb. Fourteen days after the training, participants individually constructed the solar bottle bulb. The intervention group received pictorial action instructions to guide them, and the control group completed construction based on memory. Usability was evaluated by measuring the effectiveness and efficiency of construction, as well as user satisfaction and self-efficacy levels. Effectiveness and self-efficacy were significantly better among those in the intervention group compared to the control group. Considering this, the findings support the use of pictorial action instructions in training low-literacy adults to construct humanitarian engineering projects. This method may allow more individuals in rural regions of low- and middle-income countries to successfully construct their own humanitarian engineering projects in a way that is sustainable and scalable. Further research is needed to test these instructions in different settings, on a larger scale, as well as to test the long-term effects of using pictorial action instructions. 

scholarly journals Development of HPV 16/18 E6 oncoprotein paper-based nanokit for enhanced detection of HPV 16/18 E6 oncoprotein in cervical cancer screening

2020 ◽  
Author(s):  
Lucy Muthoni Mwai ◽  
Mutinda C. Kyama ◽  
Caroline W. Ngugi ◽  
Edwin Walong
Keyword(s):  
Cervical Cancer ◽  
Gold Nanoparticles ◽  
Cancer Screening ◽  
Diagnostic Accuracy ◽  
Predictive Value ◽  
Intraepithelial Neoplasia ◽  
Hpv 16 ◽  
Middle Income ◽  
Middle Income Countries ◽  
E6 Oncoprotein

AbstractCervical cancer caused mainly by high risk human papillomavirus (HPV) 16 and 18 strains is the second most prevalent cancer of women in Kenya. It is often diagnosed late when treatment is difficult due to very low percentage of women attending screening thus, mortalities remain high. The most available tests in low-and-middle-income countries (LMICs) have relatively low specificity, low sensitivity, require a laboratory setting and huge technical and financial support not readily available. HPV 16/18 E6 oncoprotein has been identified as a potential biomarker in a more specific early diagnosis of cervical cancer. This retrospective cross-sectional study developed a paper-based nanokit with enhanced detection of HPV 16/18 E6 oncoprotein for cervical cancer screening. The HRP labelled antibodies HPV 16 E6/18 E6-HRP (CP15) passively conjugated to citrate stabilized 20nm gold nanoparticles were evaluated for immune sensing mechanism using a recombinant viral HPV E6 protein. The diagnostic accuracy was evaluated using 50 tissue lysates from formalin fixed paraffin embedded cervical biopsy, including control (n=10), Mild Dysplasia (n=10), Cervical intraepithelial neoplasia 3 (CIN3) (n=10), Cervical intraepithelial neoplasia 4 (CIN4) (n=10) and invasive carcinoma (n=10). The molecular technique used was dot blot molecular assay. A positive result was generated by catalytic oxidation of peroxidase enzyme on 3,3’,5,5’-Tetramethylbenzidine (TMB) substrate. The gold nanoparticles were used to enhance the signal produced by peroxidase activity of horseradish peroxidase (HRP) enzyme giving a more sensitive assay as compared to use of non-conjugated antibody. This study provides a significantly high and reliable diagnostic accuracy for precancerous and cancerous lesions with a sensitivity of 90%, a specificity of 90%, a likelihood ratio for positive and negative tests as 9:1 and 1:9 respectively, a Positive Predictive Value of 97.3% and a Negative Predictive Value of 69.2%. This study avails a sensitive, rapid test using paper-based nanotechnology which can be utilised in community-based screening outreaches particularly in low- and middle-income countries.

scholarly journals Hepatitis C Diagnosis: Simplified Solutions, Predictive Barriers, and Future Promises

Diagnostics ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1253
Author(s):  
Imran Shahid ◽  
Abdullah R. Alzahrani ◽  
Saeed S. Al-Ghamdi ◽  
Ibrahim M. Alanazi ◽  
Sidra Rehman ◽  
...  
Keyword(s):  
Hepatitis C ◽  
Point Of Care ◽  
Public Health Care ◽  
Clinical Experiences ◽  
Middle Income ◽  
Middle Income Countries ◽  
Care Plans ◽  
Care Cascade ◽  
Reflex Testing ◽  
Developed Nations

The simplification of current hepatitis C diagnostic algorithms and the emergence of digital diagnostic devices will be very crucial to achieving the WHO’s set goals of hepatitis C diagnosis (i.e., 90%) by 2030. From the last decade, hepatitis C diagnosis has been revolutionized by the advent and approval of state-of-the-art HCV diagnostic platforms which have been efficiently implemented in high-risk HCV populations in developed nations as well as in some low-to-middle income countries (LMICs) to identify millions of undiagnosed hepatitis C-infected individuals. Point-of-care (POC) rapid diagnostic tests (RDTs; POC-RDTs), RNA reflex testing, hepatitis C self-test assays, and dried blood spot (DBS) sample analysis have been proven their diagnostic worth in real-world clinical experiences both at centralized and decentralized diagnostic settings, in mass hepatitis C screening campaigns, and hard-to-reach aboriginal hepatitis C populations in remote areas. The present review article overviews the significance of current and emerging hepatitis C diagnostic packages to subvert the public health care burden of this ‘silent epidemic’ worldwide. We also highlight the challenges that remain to be met about the affordability, accessibility, and health system-related barriers to overcome while modulating the hepatitis C care cascade to adopt a ‘test and treat’ strategy for every hepatitis C-affected individual. We also elaborate some key measures and strategies in terms of policy and progress to be part of hepatitis C care plans to effectively link diagnosis to care cascade for rapid treatment uptake and, consequently, hepatitis C cure.

Clinical Assessment of Three Common Tests for Superior Labral Anterior-Posterior Lesions

2002 ◽  
Vol 30 (6) ◽  
pp. 810-815 ◽  
Author(s):  
Edward G. McFarland ◽  
Tae Kyun Kim ◽  
Richard M. Savino
Keyword(s):  
Positive Predictive Value ◽  
Predictive Value ◽  
Shoulder Arthroscopy ◽  
Control Group ◽  
Type I ◽  
Specific Test ◽  
Slide Test ◽  
Posterior Lesion ◽  
Sensitivity Specificity ◽  
Anterior Posterior

Background Three tests (active compression, anterior slide, and compression rotation) are commonly used to diagnose superior labral anterior-posterior lesions. Hypothesis We hypothesized that the accuracy, sensitivity, and specificity for these tests was less than that previously reported and that a click in the shoulder during manipulation was not specific for the study lesion. Study Design Case-control study. Methods The three tests were performed on 426 patients who subsequently underwent shoulder arthroscopy. The results of physical examination were compared with the arthroscopic findings and analyzed for sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy. Results At arthroscopy, 39 patients had type II to IV lesions (study group); the remaining 387 patients had type I lesion or no lesion (control group). The incidences of positive results were not statistically different between the groups (P > 0.05). Our findings were as follows: most sensitive test, active compression (47%); most specific test, anterior slide (84%); highest positive predictive value, active compression (10%); highest overall accuracy, anterior slide test (77%); lowest overall accuracy, active compression test (54%). The presence of a click and the location of the pain were not reliable diagnostic indicators. Conclusions The results of such tests should be interpreted with caution when considering surgery for a possible superior labral anterior-posterior lesion.

Association Between 45° Flexion Anteroposterior Elbow Radiographs and Diagnostic Accuracy of Capitellum Osteochondritis Dissecans

2021 ◽  
pp. 036354652110271
Author(s):  
Michael G. Saper ◽  
Viviana Bompadre ◽  
Gregory A. Schmale ◽  
Sarah Menashe ◽  
Monique Burton ◽  
...  
Keyword(s):  
Diagnostic Accuracy ◽  
Osteochondritis Dissecans ◽  
Predictive Value ◽  
Interobserver Reliability ◽  
Intraobserver Reliability ◽  
Control Group ◽  
Level Of Evidence ◽  
Level Of Confidence ◽  
High Level ◽  
Sensitivity Specificity

Background: An anteroposterior (AP) radiograph of the elbow in 45° of flexion has been suggested to increase the diagnostic accuracy of capitellum osteochondritis dissecans (OCD). Purpose: To assess the diagnostic performance, inter- and intraobserver reliability, and confidence level for identifying capitellum OCD using plain radiographs (AP, lateral, and 45° flexion AP). Study Design: Cohort study (Diagnosis); Level of evidence, 3. Methods: This was a retrospective study of pediatric and adolescent patients with capitellum OCD and a control group. Six independent clinicians who were blinded to the official radiologists’ reports reviewed images on 2 separate occasions, 1 week apart. A 5-point Likert scale was used to assess the clinicians’ level of confidence. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were calculated for individual and combinations of radiographic views. Inter- and intraobserver reliability was determined using Cohen kappa (κ) coefficients. Results: A total of 28 elbows (mean age, 12.5 ± 2 years) were included. There were no differences in age ( P = .18), sex ( P = .62), or laterality ( P > .999) between groups. There were marked variations in the diagnostic accuracy between views: sensitivity (AP, 85.1; lateral, 73.2; 45° flexion AP, 91.7), specificity (AP, 89.3; lateral, 91.7; 45° flexion AP, 91.1), PPV (AP, 88.8; lateral, 89.8; 45° flexion AP, 91.1), NPV (AP, 85.7; lateral, 77.4; 45° flexion AP, 91.6), and accuracy (AP, 87.2; lateral, 82.4; 45° flexion AP, 91.4). Standard radiographs (AP and lateral views) failed to diagnose capitellum OCD in 4.8% of cases. The sensitivity of the 3 combined views was 100%. Confidence intervals in the clinicians’ diagnostic assessments were similar for each view (AP, 4.0; lateral, 4.0; and 45° flexion AP, 4.1). Interobserver reliability was substantial for AP and lateral views (κ = 0.65 and κ = 0.60, respectively) but highest for the 45° flexion AP radiographs (κ = 0.72). Intraobserver reliability for the 45° flexion AP view was moderate to almost perfect (κ = 0.45 to 0.93). Conclusion: The 45° flexion AP view can detect capitellum OCD with excellent accuracy, a high level of confidence, and substantial interobserver agreement. When added to standard AP and lateral radiographs, the 45° flexion AP view aids in the identification of capitellum OCD.

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