scholarly journals Anti-Toxoplasma IgG assays: What performances for what purpose? A systematic review

Parasite ◽  
2021 ◽  
Vol 28 ◽  
pp. 39
Author(s):  
Florence Robert-Gangneux ◽  
Hélène Guegan

Chronic infection with Toxoplasma gondii is attested by the detection of specific anti-Toxoplasma IgG. A wide panel of serologic methods is currently marketed, and the most suitable method should be chosen according to the laboratory resources and the screened population. This systematic review of evaluation studies aimed at establishing an overview of the performances, i.e. sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of marketed anti-Toxoplasma IgG assays, and discussing their technical characteristics to guide further choice for routine diagnostic use. According to PRISMA guidelines, the search performed in PubMed and Web of Science databases recovered 826 studies, of which 17 were ultimately included. Twenty commercial anti-Toxoplasma IgG assays were evaluated, in comparison with an accepted reference method. Most of them were enzyme-immunoassays (EIAs, n = 12), followed by agglutination tests (n = 4), immunochromatographic tests (n = 3), and a Western-Blot assay (WB, n = 1). The mean sensitivity of IgG assays ranged from 89.7% to 100% for standard titers and from 13.4% to 99.2% for low IgG titers. A few studies pointed out the ability of some methods, especially WB to detect IgG early after primary infection. The specificity of IgG assays was generally high, ranging from 91.3% to 100%; and higher than 99% for most EIA assays. The PPV was not a discriminant indicator among methods, whereas significant disparities (87.5%–100%) were reported among NPVs, a key-parameter assessing the ability to definitively rule out a Toxoplasma infection in patients at-risk for opportunistic infections.

2021 ◽  
pp. 000348942199015
Author(s):  
Kevin Calamari ◽  
Stephen Politano ◽  
Laura Matrka

Objectives: Expiratory disproportion index (EDI) is the ratio of forced expiratory volume in 1 second (FEV1) divided by peak expiratory flow rate (PEFR) multiplied by 100. Prominent EDI (>50) values can differentiate subglottic stenosis (SGS) from paradoxical vocal fold movement disorder (PVFMD), but this has not been verified when considering body habitus. We hypothesize that the predictive value of elevated EDI in differentiating SGS from PVFMD will be lower in obese patients than non-obese patients. Methods: Patients ≥ 18 years old with recorded PFT values, BMI, and airway imaging were reviewed retrospectively from 01/2011 to 10/2018. EDI was recorded for 4 cohorts: non-obese/SGS, non-obese/ PVFMD, obese/SGS, and obese/ PVFMD, to determine the mean EDI and the sensitivity/specificity of an elevated EDI. Results: Mean EDI values were 69.32 and 48.38 in the non-obese SGS and PVFMD groups, respectively ( P < .01). They were 58.89 and 47.67 in the obese SGS and PVFMD groups, respectively ( P < .05). At a threshold of >50, EDI had a sensitivity of 90.0% and specificity of 51.6% in differentiating between SGS and PVFMD cases in non-obese patients and 51.6% and 63.6% in obese patients. Conclusion: Prior literature has established that EDI can distinguish SGS from PVFMD in the general population. Our results show that the mean EDI values were significantly different in both cohorts, but an elevated EDI was not as sensitive at identifying SGS cases in obese patients. This suggests that the EDI should be used with caution in obese patients and should not be relied upon to rule out SGS. Level of Evidence: 3.


2020 ◽  
pp. archdischild-2020-320549
Author(s):  
Fang Hu ◽  
Shuai-Jun Guo ◽  
Jian-Jun Lu ◽  
Ning-Xuan Hua ◽  
Yan-Yan Song ◽  
...  

BackgroundDiagnosis of congenital syphilis (CS) is not straightforward and can be challenging. This study aimed to evaluate the validity of an algorithm using timing of maternal antisyphilis treatment and titres of non-treponemal antibody as predictors of CS.MethodsConfirmed CS cases and those where CS was excluded were obtained from the Guangzhou Prevention of Mother-to-Child Transmission of syphilis programme between 2011 and 2019. We calculated sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) using receiver operating characteristics (ROC) in two situations: (1) receiving antisyphilis treatment or no-treatment during pregnancy and (2) initiating treatment before 28 gestational weeks (GWs), initiating after 28 GWs or receiving no treatment for syphilis seropositive women.ResultsAmong 1558 syphilis-exposed children, 39 had confirmed CS. Area under the curve, sensitivity and specificity of maternal non-treponemal titres before treatment and treatment during pregnancy were 0.80, 76.9%, 78.7% and 0.79, 69.2%, 88.7%, respectively, for children with CS. For the algorithm, ROC results showed that PPV and NPV for predicting CS were 37.3% and 96.4% (non-treponemal titres cut-off value 1:8 and no antisyphilis treatment), 9.4% and 100% (non-treponemal titres cut-off value 1:16 and treatment after 28 GWs), 4.2% and 99.5% (non-treponemal titres cut-off value 1:32 and treatment before 28 GWs), respectively.ConclusionsAn algorithm using maternal non-treponemal titres and timing of treatment during pregnancy could be an effective strategy to diagnose or rule out CS, especially when the rate of loss to follow-up is high or there are no straightforward diagnostic tools.


2010 ◽  
Vol 20 (5) ◽  
pp. 862-868 ◽  
Author(s):  
Pakhee Aggarwal ◽  
Swaraj Batra ◽  
Gauri Gandhi ◽  
Vijay Zutshi

Objectives:To compare the sensitivity, specificity, positive and negative predictive values, and accuracy of Papanicolaou test with visual inspection with acetic acid (VIA)/VIA using magnification devices (VIAM) and develop the best strategy for screening in low resource settings.Materials and Methods:This is a prospective cross-sectional study on 408 symptomatic multiparous women in the reproductive age group, sequentially using the Papanicolaou test, the VIA, and the VIAM for screening. Women with a positive screening test underwent guided biopsy and endocervical curettage. The site of biopsy was recorded. Histopathological findings were taken as the "gold" standard in comparing the methods.Results:The mean (SD) age was 32.3 (6.8) years (range, 15-49 years), whereas the mean (SD) parity was 2.9 (1.2) (range, 1-9). Abnormal cytological findings were detected in 2.9% patients, whereas the remaining smears were negative for any intraepithelial lesion or malignancy. A total of 113 cases were screened positive by one/all methods. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the Papanicolaou test, the VIA, and the VIAM were 24, 98, 42, 96, and 94%; 95, 78, 19, 99, and 79%; and 95, 78, 19, 99, and 79%, respectively, for high-grade lesions.Conclusions:The Papanicolaou test had low sensitivity but high specificity, whereas visual detection methods had a high sensitivity in addition to being cheaper. Alternative methods of screening such as VIA/VIAM can be a valuable alternative to the Papanicolaou test for cervical cancer screening in low resource settings. Visual inspection using magnification devices may be of benefit over VIA in doubtful cases.


Sarcoma ◽  
2020 ◽  
Vol 2020 ◽  
pp. 1-6 ◽  
Author(s):  
Marc El Beaino ◽  
Daniel C. Jupiter ◽  
Tarek Assi ◽  
Elie Rassy ◽  
Alexander J. Lazar ◽  
...  

Background. Synovial sarcoma can present morphologically in multiple forms, including biphasic and monophasic subtypes. As a result, the histological diagnosis can sometimes be challenging. Transducin-Like Enhancer 1 (TLE1) is a transcriptional corepressor that normally is involved in embryogenesis and hematopoiesis but is also expressed in certain tumors. This systematic review examines the potential role of TLE1 as a diagnostic biomarker for the synovial sarcoma. Materials and Methods. A literature review and meta-analysis were conducted using the electronic databases Pubmed, the Cochrane Library, and Google Scholar. Thirteen studies met our eligibility criteria and were selected for in-depth analysis. Results. The mean sensitivity and specificity of TLE1 in detecting synovial sarcoma were 94% (95% CI 91%–97%) and 81% (95% CI 72%–91%), respectively, when all studies were aggregated together. The mean positive predictive value (PPV) of TLE1 was 75% (95% CI 62%–87%), whereas the negative predictive value (NPV) was 96% (95% CI 93%–98%). Conclusion. TLE1 is a sensitive and specific marker for synovial sarcoma that can aid in its diagnosis. Due to its involvement in several relevant signaling pathways, TLE1 might have direct relevance to the pathophysiology of the disease.


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
R Elnagar ◽  
U Ghieda ◽  
A Ibrahim ◽  
M Dawoud

Abstract Background Multi-detector computed tomography (MDCT) has become an effective tool in the assessment of congenital heart disease in infants and children. Purpose To evaluate the role of 320-row MDCT in the assessment of conotruncal anomalies and compare it with echocardiography (echo) considering the operative and/or catheter findings as the gold standard. Methods The studied group included 50 patients having conotruncal anomalies. All patients were evaluated with 320-row MDCT angiography. Sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) of MDCT and echo were calculated. The patient effective dose was reported. Results The overall sensitivity, specificity, accuracy, PPV and NPV for MDCT angiography in assessment of various abnormalities in patients with conotruncal anomalies were 98.97%, 100%, 99.75%, 100% and 99.67% for MDCT angiography. Sensitivity, specificity, PPV and NPV of MDCT angiography were 97.87%, 100%, 100% and 99.04% and 99.49%, 100%, 100% &99.86% for the detection of intracardiac defects and extracardiac vascular anomalies respectively. The mean absorbed radiation dose was 63.63 mGy-Cm per scan and the mean effective dose was 1.56±0.47 mSv. Conclusion 320-MDCT angiography offers an excellent diagnostic procedure in the preoperative evaluation of the complex anatomy of the conotruncal anomalies. Funding Acknowledgement Type of funding source: None


Author(s):  
Antonio Barbaro ◽  
Thomas A Eldredge ◽  
Jonathan Shenfine

SUMMARY Esophagectomy is the gold-standard treatment for esophageal cancer; however, postoperative anastomotic leakage remains the primary concern for surgeons. No consensus exists on the optimal investigations to predict an anastomotic leak. This systematic review aims to identify a single test or combination of tests with acceptable sensitivity and specificity to identify anastomotic leak after esophagectomy and to formulate a diagnostic algorithm to facilitate surgical decision-making. A systematic review of PubMed and EMBASE databases was undertaken to evaluate diagnostic investigations for anastomotic leak post-esophagectomy. Each study was reviewed and where possible, the sensitivity, specificity, positive predictive value, and negative predictive value were extracted. The review identified 3,204 articles, of which 49 met the inclusion criteria. Investigations most commonly used for diagnosis of anastomotic leak were: C-reactive protein (CRP), oral contrast imaging, computed tomography (CT), pleural drain amylase concentration, and the ‘NUn score’. The sensitivity of CRP for detecting anastomotic leak varied from 69.2% to 100%. Oral contrast studies sensitivities varied between 16% and 87.5% and specificity varied from 20% to 100%. Pleural drain amylase sensitivities ranged between 75% and 100% and specificity ranged from 52% to 95.5%. The NUn score sensitivities ranged from 0% to 95% and specificity from 49% to 94.4%. No single investigation was identified to rule out anastomotic leak in asymptomatic patients. However, the authors propose a diagnostic algorithm incorporating CRP, pleural drain amylase concentration, and CT with oral contrast to aid clinicians in predicting anastomotic leak to facilitate safe, timely discharge post-esophagectomy.


2020 ◽  
Vol 7 (1) ◽  
pp. e000355 ◽  
Author(s):  
Rohit Hariharan ◽  
Mark Jenkins

BackgroundCirculating tumour DNA from colorectal cancer (CRC) is a biomarker for early detection of the disease and therefore potentially useful for screening. One such biomarker is the methylated SEPT9 (mSEPT9) gene, which occurs during CRC tumourigenesis. This systematic review and meta-analysis aims to establish the sensitivity, specificity and accuracy of mSEPT9 tests for the early diagnosis of CRC.MethodsA systematic search of the relevant literature was conducted using Medline and Embase databases. Data were extracted from the eligible studies and analysed to estimate pooled sensitivity, specificity and diagnostic test accuracy.ResultsBased on 19 studies, the pooled estimates (and 95% CIs) for mSEPT9 to detect CRC were: sensitivity 69% (62–75); specificity 92% (89–95); positive likelihood ratio 9.1 (6.1–13.8); negative likelihood ratio 0.34 (0.27–0.42); diagnostic OR 27 (15–48) and area under the curve 0.89 (0.86–0.91). The test has a positive predictive value of 2.6% and negative predictive value of 99.9% in an average risk population (0.3% CRC prevalence), and 9.5% (positive predictive value) and 99.6% (negative predictive value) in a high-risk population (1.2% CRC prevalence).ConclusionThe mSEPT9 test has high specificity and moderate sensitivity for CRC and is therefore a potential alternative screening method for those declining faecal immunochemical test for occult blood (FIT) or other screening modalities. However, it is limited by its poor diagnostic performance for precancerous lesions (advanced adenomas and polyps) and its relatively high costs, and little is known about its acceptability to those declining to use the FIT.


2020 ◽  
Author(s):  
Elmir Elharti ◽  
Halima Abbadi ◽  
Rajae Bensghir ◽  
Kamal Marhoum El Filali ◽  
Hajar Elmrabet ◽  
...  

Abstract Background : In the era of “test and treat strategy”, CD4 testing remains an important tool for monitoring HIV-infected individuals. Since conventional methods of CD4 count measurement are costly and cumbersome, POC CD4 counting technique are more affordable and practical for countries with limited resources. Before introducing such methods in Morocco, we decided to assess their reliability. Methods : In this study 92 blood samples from HIV-infected patients, were tested by PIMA and FACSPresto to derive CD4 count. Flow cytometry using FacsCalibur, was used as reference method for CD4 count comparison. Linear regression, Bland-Altman analysis were performed to assess correlation and agreement between these POC methods and the reference method. In addition, sensitivity and specificity, positive predictive value (PPV), negative predictive value (NPV) and misclassification percentage at 350 and 200 CD4 count thresholds; were also determined. Finally, because FACSPresto can also measure hemoglobin (Hb) concentration, 52 samples were used to compare FACSPresto against an automated hematology analyzer. Results : The coefficient of determination R 2 was 0.93 for both methods. Bland-Altman analysis displayed a mean bias of -32.3 and -8.1 cells/µl for PIMA and FACSPresto, respectively. Moreover, with a threshold of 350 CD4 count, PIMA displayed a sensitivity, specificity, PPV, NPV, were 88.57%, 94.12%, 91.18%, 92.31%; respectively. FACSPresto showed 88.23%, 96.23%,93.75% and 92.73%; respectively. Furthermore, the upward misclassification percentage was 8.57 and 5.88%, for PIMA and FACSPresto, respectively; whereas the downward misclassification percentage was 7.84% and 7.54%; respectively. With 200 cells/µl threshold, PIMA had a sensitivity, specificity, PPV and NPV of 83.33%, 98.53%, 93.75% and 95.71%, respectively. Regarding FACSPresto, sensitivity, specificity, PPV and NPV was 82.35%, 98.57%, 88.57% and 95.83%; respectively. Upward misclassification percentage was 5.56% and 5.88%, for PIMA and FACSPresto, respectively; whereas downward misclassification percentage was 4.41% and 4.29%; respectively. Finally, the hemoglobin measurement evaluation displayed an R 2 of 0.80 and a mean bias of-0.12 with a LOA between -1.75 and 1.51. Conclusion : When compared to the reference method, PIMA and FACSPresto have shown good performance, for CD4 counting. The introduction of such POC technology will speed up the uptake of patients in the continuum of HIV care, in our country.


2020 ◽  
Author(s):  
Hairu Li ◽  
Yulan Peng ◽  
Yan Wang ◽  
Hong Ai ◽  
Xiaodong Zhou ◽  
...  

Abstract Background: An accurate diagnosis for high-suspicion nodules based on the 2015 American Thyroid Association (ATA) guidelines would reduce unnecessary invasive examinations. Elastography is a useful tool for discriminating benign and malignant thyroid nodules. The aim of this study is to investigate the diagnostic efficiency of elastography for high-suspicion thyroid nodules based on the 2015 ATA guidelines in the Chinese population.Methods: Thyroid nodules with high-suspicion characteristics based on the 2015 ATA guidelines were subjected to conventional ultrasound (US) and ultrasound strain elastography (USE) examinations at 12 hospitals from 4 geographic regions across China. Cytology/histology of thyroid nodules was used as a reference method. Receiver operating characteristic (ROC) curves were plotted to evaluate the diagnostic performance of the elasticity score (ES) and strain ratio (SR). Logistic regression analysis was used to determine the predictors of malignancy.Results: Overall, a total of 1445 thyroid nodules (834 malignant, 611 benign) from 12 centers were included in the final analysis. The areas under the curve of the ES and SR were 0.828 and 0.732, respectively. The sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) of the ES were 92.4%, 60.7%, 79.0%, 76.3% and 85.5%, respectively, and those of the SR were 81.1%, 50.1%, 68.9%, 65.9% and 67.9%, respectively. The combination of the Thyroid Imaging Reporting and Data System (TI-RADS) and ES led to a significant increase in the sensitivity and NPV (97.1% and 91.9%, respectively) compared with the TI-RADS alone. Logistic regression analysis showed that microcalcifications (OR=5.290), taller than wide (OR=12.710), irregular margins (OR=10.117), extrathyroidal extension (ETE; OR=6.412), the ES (OR=3.741) and the SR (OR=1.083) were independent predictors of malignant thyroid nodules. The sensitivity, specificity, accuracy, PPV and NPV of the ES were all superior in nodules ≥1 cm than in those <1 cm (95.0% vs 90.4%, 68.8% vs 56.8%, 85.9% vs 74.4%, 85.2% vs 69.9%, and 87.8% vs 84.2%, respectively).Conclusions: Elastography combined with the ES is a valuable tool for the assessment of high-suspicion thyroid nodules based on the 2015 ATA guidelines, especially in nodules ≥1 cm.


2020 ◽  
Author(s):  
Hairu Li ◽  
Yulan Peng ◽  
Yan Wang ◽  
Hong Ai ◽  
Xiaodong Zhou ◽  
...  

Abstract Background: An accurate diagnosis for high-suspicion nodules based on the 2015 American Thyroid Association (ATA) guidelines would reduce unnecessary invasive examinations. Elastography is a useful tool for discriminating benign and malignant thyroid nodules.Aims: To investigate the diagnostic efficiency of elastography for high-suspicion thyroid nodules based on the 2015 ATA guidelines in the Chinese population.Materials and Methods: Thyroid nodules with high-suspicion characteristics based on the 2015 ATA guidelines were subjected to conventional ultrasound (US) and ultrasound strain elastography (USE) examinations at 12 hospitals from 4 geographic regions across China. Cytology/histology of thyroid nodules was used as a reference method. Receiver operating characteristic (ROC) curves were plotted to evaluate the diagnostic performance of the elasticity score (ES) and strain ratio (SR). Logistic regression analysis was used to determine the predictors of malignancy.Results: Overall, a total of 1445 thyroid nodules (834 malignant, 611 benign) from 12 centers were included in the final analysis. The areas under the curve of the ES and SR were 0.828 and 0.732, respectively. The sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) of the ES were 92.4%, 60.7%, 79.0%, 76.3% and 85.5%, respectively, and those of the SR were 81.1%, 50.1%, 68.9%, 65.9% and 67.9%, respectively. The combination of the Thyroid Imaging Reporting and Data System (TI-RADS) and ES led to a significant increase in the sensitivity and NPV (97.1% and 91.9%, respectively) compared with the TI-RADS alone. Logistic regression analysis showed that microcalcifications (OR=5.290), taller than wide (OR=12.710), irregular margins (OR=10.117), extrathyroidal extension (ETE; OR=6.412), the ES (OR=3.741) and the SR (OR=1.083) were independent predictors of malignant thyroid nodules. The sensitivity, specificity, accuracy, PPV and NPV of the ES were all superior in nodules ≥1 cm than in those <1 cm (95.0% vs 90.4%, 68.8% vs 56.8%, 85.9% vs 74.4%, 85.2% vs 69.9%, and 87.8% vs 84.2%, respectively).Conclusions: Elastography combined with the ES is a valuable tool for the assessment of high-suspicion thyroid nodules based on the 2015 ATA guidelines, especially in nodules ≥1 cm.


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