scholarly journals Delineating a Retesting Zone Using Receiver Operating Characteristic Analysis on Serial QuantiFERON Tuberculosis Test Results in US Healthcare Workers

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Wendy Thanassi ◽  
Art Noda ◽  
Beatriz Hernandez ◽  
Jeffery Newell ◽  
Paul Terpeluk ◽  
...  
Keyword(s):  
Regression Analysis ◽  
Receiver Operating Characteristic ◽  
Healthcare Workers ◽  
Operating Characteristic ◽  
Receiver Operating Characteristic Analysis ◽  
Low Risk ◽  
Separation Point ◽  
Characteristic Analysis ◽  
Chi Square ◽  
Receiver Operating

Objective. To find a statistically significant separation point for the QuantiFERON Gold In-Tube (QFT) interferon gamma release assay that could define an optimal “retesting zone” for use in serially tested low-risk populations who have test “reversions” from initially positive to subsequently negative results.Method. Using receiver operating characteristic analysis (ROC) to analyze retrospective data collected from 3 major hospitals, we searched for predictors of reversion until statistically significant separation points were revealed. A confirmatory regression analysis was performed on an additional sample.Results. In 575 initially positive US healthcare workers (HCWs), 300 (52.2%) had reversions, while 275 (47.8%) had two sequential positive tests. The most statistically significant (Kappa = 0.48, chi-square = 131.0,P<0.001) separation point identified by the ROC for predicting reversion was the tuberculosis antigen minus-nil (TBag-nil) value at 1.11 International Units per milliliter (IU/mL). The second separation point was found at TBag-nil at 0.72 IU/mL (Kappa = 0.16, chi-square = 8.2,P<0.01). The model was validated by the regression analysis of 287 HCWs.Conclusion. Reversion likelihood increases as the TBag-nil approaches the manufacturer's cut-point of 0.35 IU/mL. The most statistically significant separation point between those who test repeatedly positive and those who revert is 1.11 IU/mL. Clinicians should retest low-risk individuals with initial QFT results < 1.11 IU/mL.

scholarly journals 419. Diagnostic Utility of a Ferritin to Procalcitonin Ratio to Differentiate Patients with COVID-19 from Those with Bacterial Pneumonia

2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S277-S277
Author(s):  
Katherine C Jankousky ◽  
Peter Hyson ◽  
Jin Huang ◽  
Daniel B Chastain ◽  
Carlos Franco-Paredes ◽  
...  
Keyword(s):  
Receiver Operating Characteristic ◽  
Host Response ◽  
Bacterial Pneumonia ◽  
Operating Characteristic ◽  
Receiver Operating Characteristic Analysis ◽  
University Hospital ◽  
Characteristic Analysis ◽  
The Us ◽  
Test Probability ◽  
Receiver Operating

Abstract Background Accurate, rapid, inexpensive biomarkers are needed to differentiate COVID-19 from bacterial pneumonia, allowing effective treatment and antibiotic stewardship. We hypothesized that the ratio of ferritin to procalcitonin (F/P) reflects greater viral activity and host response with COVID-19 pneumonia, while bacterial pneumonia would be associated with less cytolysis (lower ferritin) and more inflammation (higher procalcitonin), thus a lower F/P ratio. Methods We conducted a retrospective study of adult patients admitted to a single University hospital in the US through May 2020, during the COVID-19 pandemic. We compared F/P ratio of patients diagnosed with COVID-19 or bacterial pneumonia, excluding patients with COVID-19 and bacterial co-infections. In a logistic regression, we controlled for age, sex, body mass index (BMI), diabetes (DM), and hypertension (HTN). We used a receiver operating characteristic analysis to calculate the sensitivity and specificity of F/P values for the diagnosis of COVID-19 versus bacterial pneumonia. Results Of 218 patients with COVID-19 and 17 with bacterial pneumonia, COVID-19 patients were younger (56 vs 66 years, p=0.04), male (66% vs 24%, p=0.009), had higher BMI (31 vs 27 kg/m2, p=0.03), and similar rates of HTN (59% vs 45%, p=0.3) and DM (32% vs 18%, p=0.2). The median F/P ratio was significantly higher in patients with COVID-19 (3195 vs 860, p=0.0003, Figure 1). An F/P ratio cut-off of ≥ 1250 generated a sensitivity of 78% and a specificity of 59% to correctly classify a COVID-19 case (Figure 2). When adjusted for age, gender, BMI, DM, and HTN, a ratio ≥ of 1250 was associated with significantly greater odds of COVID-19 versus bacterial pneumonia (OR: 4.9, CI: 1.5, 16.1, p=0.009). Figure 1. Ferritin to Procalcitonin Ratios of patients with COVID-19 and patients with Bacterial Pneumonia (controls). Figure 2. Receiver Operating Characteristic Analysis of Ferritin to Procalcitonin Ratio Cut-off Values Predicting COVID-19 Diagnosis. Conclusion We observed an elevated F/P ratio in patients with COVID-19 compared to those with bacterial pneumonia. A F/P ratio ≥ 1250 provides a clinically relevant increase in pre-test probability of COVID-19. Prospective studies evaluating the discriminatory characteristics of F/P ratio in larger cohorts is warranted. Disclosures All Authors: No reported disclosures

Biomarker panels may be superior over single molecules in prediction of renal flares in systemic lupus erythematosus: an exploratory study

Rheumatology ◽  
2020 ◽  
Vol 59 (11) ◽  
pp. 3193-3200
Author(s):  
Serena Fasano ◽  
Luciana Pierro ◽  
Alessia Borgia ◽  
Melania Alessia Coscia ◽  
Ranieri Formica ◽  
...  
Keyword(s):  
Receiver Operating Characteristic ◽  
Adhesion Molecule ◽  
Operating Characteristic ◽  
Cox Regression ◽  
Receiver Operating Characteristic Analysis ◽  
Characteristic Analysis ◽  
Factors Associated ◽  
Biomarker Panel ◽  
Renal Flare ◽  
Receiver Operating

Abstract Objective Recent evidence suggests that some urinary biomarkers, namely Vascular Cell Adhesion Molecule-1 (VCAM-1), Intercellular Adhesion Molecule-1 (ICAM-1), Monocyte Chemoattractant Protein 1 (MCP-1), Neutrophil Gelatinase Associated Lipocalcin and Lipocalin-type Prostaglandin D-Synthetase (L-PGDS), might discriminate SLE patients with ongoing renal activity from those with stable disease. The objective of this study was to assess the role of these markers in predicting renal flares in comparison with conventional biomarkers and to derive a biomarker panel which may improve diagnostic accuracy. Methods Eligible participants were SLE patients prospectively followed at our clinic. Urinary biomarker levels were measured in urinary sample by ELISA assay and were compared by the unpaired Student’s t test or the Mann–Whitney U test as appropriate. Receiver operating characteristic analysis was used to calculate the area under the curve. Cox regression was used to identify independent factors associated with disease flares. Results Urine was collected from 61 patients. During 8 months’ follow-up, eight patients experienced a renal flare. Urinary L-PGDS, ICAM-1 and VCAM-1 levels were significantly increased in the patients who subsequently experienced a renal flare with respect to the remaining 53. At Cox regression analysis, L-PGDS, ICAM-1, VCAM-1, hypocomplementemia and anti-dsDNA antibodies were factors associated with renal flares. Based on receiver operating characteristic analysis, a combination of novel and conventional biomarkers demonstrated an excellent ability for accurately identifying a flare. Conclusion This study might suggest the usefulness of a novel biomarker panel in predicting a renal flare in SLE.

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