Comparison of admission chest computed tomography and lung ultrasound performance for diagnosis of COVID-19 pneumonia in populations with different disease prevalence

Abstract

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.

Correlation between lung ultrasound and chest CT patterns with estimation of pulmonary burden in COVID-19 patients

“…In the current study, almost all patients with lung abnormalities on the chest CT scan were correctly classified as positive by LUS, showing its reliability for case identification. This corresponds with the current results of the literature, which reports a very high sensitivity (89-100%) for the diagnosis of COVID-19[ [29] , [30] , [31] ].…”

“…Actually, in the per patient analysis LUS performed very well since the detection of just one lung zone was sufficient to classify the COVID-19 patient as positive. On the contrary, the per zone performance was lower due to false positive and false negative findings that affected the LUS scoring system, which is congruent with previous works that demonstrated only a fair-to-moderate localization agreement between LUS and CT findings[ 31 , 38 ]. This may explain why CT and LUS severity indices appeared to be correlated but with a considerable dispersion of the values around the hypothetical trendline.…”

Point-of-care lung ultrasound assessment for risk stratification and therapy guiding in COVID-19 patients: a prospective noninterventional study

“…Due to its sensitivity, pulmonary computed tomography (CT) has been postulated as the "gold standard" to detect lung involvement [8,9]. However, lung CT has some limitations,especially when repeated examinations are required: equipment is not always available due to high demand, radiation exposure, the need to move around the patient, or the subsequent need of enhanced environmental cleaning after its use, all of them inconvenient and time-consuming.…”

Clinical Characteristics of the COVID-19 Patients with Pneumonia Detected by Computerized Tomography but Negative for Infiltration by X-ray

“…In the current pandemic situation of COVID-19, the use of effective and efficient diagnostics is of paramount importance in the prevention and control of the disease. The more commonly used diagnostic tools in the detection of COVID-19-associated pneumonic lungs are CXR, lung ultrasound (LUS) and CT scans, with their varying degree of sensitivity and specificity [ 20 ]. In addition, there are obviously pros and cons of these different diagnostic tools in terms of detectability, feasibility, and cost considerations [ 20 , 21 ].…”

“…The more commonly used diagnostic tools in the detection of COVID-19-associated pneumonic lungs are CXR, lung ultrasound (LUS) and CT scans, with their varying degree of sensitivity and specificity [ 20 ]. In addition, there are obviously pros and cons of these different diagnostic tools in terms of detectability, feasibility, and cost considerations [ 20 , 21 ]. For instance, compared with CT scans and CXR, LUS lacks exposure to radiation and, thus, might be particularly useful in critical care settings and for pregnant women, children, and patients in areas with high rates of community transmission of SARS-CoV-2 infection [ 21 ].…”