Diagnostic performance of chest radiography in high COVID-19 prevalence setting: experience from a European reference hospital.
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ABSTRACT: Purpose
The study's aim is to analyse the diagnostic performance of chest radiography (CXR) in patients with suspected coronavirus disease 19 (COVID-19).Methods
We retrospectively considered 826 consecutive patients with suspected COVID-19 presenting to our emergency department (ED) from February 21 to March 31, 2020, in a high disease prevalence setting. We enrolled patients who underwent CXR and rhino-oropharyngeal swab for real-time reverse transcription-polymerase chain reaction (rRT-PCR). CXRs were evaluated by an expert radiologist; a second independent analysis was performed by two residents in consensus. All readers, blinded to rRT-PCR results, classified CXRs positive/negative depending on presence/absence of typical findings of COVID-19, using rRT-PCR as reference standard.Results
We finally analysed 680 patients (median age 58); 547 (80%) tested positive for COVID-19. The diagnostic performance of CXR, interpreted by the expert reader, was as follows: sensitivity (79.0%; 95% CI: 75.3-82.3), specificity (81.2%; 95% CI: 73.5-87.5), PPV (94.5%;95% CI: 92.0-96.4), NPV (48.4%; 95% CI: 41.7-55.2), and accuracy (79.3%; 95% CI: 76.0-82.2). For the residents: sensitivity (75.1%; 95% CI: 71.2-78.7), specificity (57.9%; 95% CI: 49.9-66.4), PPV (88.0%; 95% CI: 84.7-90.8), NPV (36.2%; 95% CI: 29.7-43.0), and accuracy (71.6%; 95% CI: 68.1-75.0). We found a significant difference between the reporting sensitivity (p = 0.013) and specificity (p < 0.0001) of expert radiologist vs residents. CXR sensitivity was higher in patients with symptom onset > 5 days before ED presentation compared to ≤ 5 days (84.4% vs 70.7%).Conclusions
CXR showed a sensitivity of 79% and a specificity of 81% in diagnosing viral pneumonia in symptomatic patients with clinical suspicion of COVID-19. Further studies in lower prevalence settings are needed.
SUBMITTER: Flor N
PROVIDER: S-EPMC8254671 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:Background: Patients with heart failure (HF) often display dyspnea associated with pulmonary congestion, along with intravascular congestion, both may result in urgent hospitalization and subsequent death. A combination of radiographic pulmonary congestion and plasma volume might screen patients with a high risk of in-hospital mortality in the emergency department (ED). Methods: In the pathway of dyspneic patients in emergency (PARADISE) cohort, patients admitted for acute HF were stratified into 4 groups based on high or low congestion score index (CSI, ranging from 0 to 3, high value indicating severe congestion) and estimated plasma volume status (ePVS) calculated from hemoglobin/hematocrit. Results: In a total of 252 patients (mean age, 81.9 years; male, 46.8%), CSI and ePVS were not correlated (Spearman rho <0 .10, p > 0.10). High CSI/high ePVS was associated with poorer renal function, but clinical congestion markers (i.e., natriuretic peptide) were comparable across CSI/ePVS categories. High CSI/high ePVS was associated with a four-fold higher risk of in-hospital mortality (adjusted-OR, 95%CI = 4.20, 1.10-19.67) compared with low CSI/low ePVS, whereas neither high CSI nor ePVS alone was associated with poor prognosis (all-p-value > 0.10; Pinteraction = 0.03). High CSI/high ePVS improved a routine risk model (i.e., natriuretic peptide and lactate)(NRI = 46.9%, p = 0.02), resulting in high prediction of risk of in-hospital mortality (AUC = 0.85, 0.82-0.89). Conclusion: In patients hospitalized for acute HF with relatively old age and comorbidity burdens, a combination of CSI and ePVS was associated with a risk of in-hospital death, and improved prognostic performance on top of a conventional risk model.
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