Current best evidence for clinical care (more info)
PURPOSE: Chest computed tomography (CT) is considered a reliable imaging tool for COVID-19 pneumonia diagnosis, while lung ultrasound (LUS) has emerged as a potential alternative to characterize lung involvement. The aim of the study was to compare diagnostic performance of admission chest CT and LUS for the diagnosis of COVID-19.
METHODS: We included patients admitted to emergency department between February 21-March 6, 2020 (high prevalence group, HP) and between March 30-April 13, 2020 (moderate prevalence group, MP) undergoing LUS and chest CT within 12?h. Chest CT was considered positive in case of "indeterminate"/"typical" pattern for COVID-19 by RSNA classification system. At LUS, thickened pleural line with?=?three B-lines at least in one zone of the 12 explored was considered positive. Sensitivity, specificity, PPV, NPV, and AUC were calculated for CT and LUS against real-time reverse transcriptase polymerase chain reaction (RT-PCR) and serology as reference standard.
RESULTS: The study included 486 patients (males 61 %; median age, 70 years): 247 patients in HP (COVID-19 prevalence 94 %) and 239 patients in MP (COVID-19 prevalence 45 %). In HP and MP respectively, sensitivity, specificity, PPV, and NPV were 90-95 %, 43-69 %, 96-72 %, 20-95 % for CT and 94-93 %, 7-31 %, 94-52 %, 7-83 % for LUS. CT demonstrated better performance than LUS in diagnosis of COVID-19, both in HP (AUC 0.75 vs 0.51; P?<?0.001) and MP (AUC 0.85 vs 0.62; P?<?0.001).
CONCLUSIONS: Admission chest CT shows better performance than LUS for COVID-19 diagnosis, at varying disease prevalence. LUS is highly sensitive, but not specific for COVID-19.
| Discipline / Specialty Area | Score |
|---|---|
| Respirology/Pulmonology | |
| Infectious Disease | |
| Emergency Medicine | |
The study has several important limitations that make it less useful for intensivists.
This is a nice article, but sensitivity, specificity etc. depends on definition of what signs are needed for a "positive" ultrasound examination.
This article compares ultrasound to the "gold standard" of CT for the diagnosis of coronavirus lung disease. There are many challenges in this kind of comparison and their results may not be entirely reproducible elsewhere. Ultrasound was less reliable that CT; although, it had some utility. In a setting were CT cannot be done, it might still be worth using ultrasound as part of the diagnostic workup but it would not be the preferred modality. Incidentally this was one of the hardest articles I have ever read for MORE.
Although we are not relying on ultrasound for diagnosis of pneumonia in the clinical settings in which I practice, I am seeing more doctors using ultrasound as an extension of their physical examination and the performance of ultrasound in this data set of almost 500 patients was interesting.