Diagnostic accuracy of a set of clinical and radiological criteria for screening of COVID-19 using RT-PCR as the reference standard

Abstract

Background The gold-standard method for establishing a microbiological diagnosis of COVID-19 is reverse-transcriptase polymerase chain reaction (RT-PCR). This study aimed to evaluate the accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of a set of clinical-radiological criteria for COVID-19 screening in patients with severe acute respiratory failure (SARF) admitted to intensive care units (ICUs), using reverse-transcriptase polymerase chain reaction (RT-PCR) as the reference standard. Methods Diagnostic accuracy study including a historical cohort of 1009 patients consecutively admitted to ICUs across six hospitals in Curitiba (Brazil) from March to September, 2020. The sample was stratified into groups by the strength of suspicion for COVID-19 (strong versus weak) using parameters based on three clinical and radiological (chest computed tomography) criteria. The diagnosis of COVID-19 was confirmed by RT-PCR (referent). Results With respect to RT-PCR, the proposed criteria had 98.5% (95% confidence interval [95% CI] 97.5–99.5%) sensitivity, 70% (95% CI 65.8–74.2%) specificity, 85.5% (95% CI 83.4–87.7%) accuracy, PPV of 79.7% (95% CI 76.6–82.7%) and NPV of 97.6% (95% CI 95.9–99.2%). Similar performance was observed when evaluated in the subgroups of patients admitted with mild/moderate respiratory disfunction, and severe respiratory disfunction. Conclusion The proposed set of clinical-radiological criteria were accurate in identifying patients with strong versus weak suspicion for COVID-19 and had high sensitivity and considerable specificity with respect to RT-PCR. These criteria may be useful for screening COVID-19 in patients presenting with SARF.

Typical phenotypes of patients with acute respiratory failure with and without COVID-19 and their relationship with outcomes: a cohort study

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Accuracy of the persistent AKI risk index in predicting acute kidney injury in patients admitted to the intensive care unit for acute respiratory failure

“…Patients were considered to have acute respiratory failure when they presented two or more of the following clinical and radiological criteria: (A) at least one flu-like illness, that is, cough, runny nose, fever, or sore throat; (B) at least two points on the modified quick Sepsis-related Organ Failure Assessment (qSOFA) (systolic blood pressure < 100mmHg, respiratory rate > 22bpm, lowered consciousness level with Glasgow coma scale score < 15 and/or pulse oxygen saturation < 93%); and (C) chest computed tomography suggestive of coronavirus disease 2019 (COVID-19) (ground-glass opacity and peripheral lesions distributed in both lungs) within the first 48 hours after admission. ( 9 )…”

Manifestaciones cardíacas y hallazgos ecocardiográficos asociados al síndrome inflamatorio multisistémico por COVID-19 en niños

“…The RT-PCR test is considered the gold standard for diagnosing SARS-CoV-2 infection due to its high sensitivity and specificity, especially in more advanced stages of the disease. In these cases, antigen testing may be less effective due to decreased viral load [19]. The RT-PCR test can accurately detect the virus even at lower concentrations, which is crucial for identifying cases where the infection has passed the acute phase but could still contribute to developing complications such as MIS-C [20].…”