CT screening for COVID-19 in asymptomatic patients before hospital admission

Abstract

Introduction In the novel coronavirus disease (COVID-19) pandemic era, it is essential to rule out COVID-19 effectively to prevent transmission in both communities and medical facilities. According to previous reports in high prevalence areas, CT screening may be useful in the diagnosis of COVID-19. However, the value of CT screening in low prevalence areas has scarcely been reported. Methods This report examines the diagnostic efficacy of CT screening before admission to a hospital in Tokyo. We conducted a retrospective analysis at Keio University Hospital from April 6, 2020, through May 29, 2020. We set up an outpatient screening clinic on April 6 for COVID-19, administering both PCR with nasopharyngeal swabs and chest CT for all patients scheduled for surgery under general anesthesia. Results A total of 292 asymptomatic patients were included in this study. There were three PCR-positive patients, and they all had negative CT findings, which revealed that both the sensitivity and positive predictive value of CT (PPV) were 0%. There were nine CT-positive patients; the specificity and the negative predictive value (NPV) were 96.9% and 98.9%, respectively. Conclusion CT screening was not useful in low prevalence areas at this time in Tokyo, even with the inclusion of the most prevalent phase. Given that the utility of CT screening depends on disease prevalence, the criteria for performing CT screening based on the prevalence of COVID-19 should be established.

Preoperative SARS-CoV-2 Infection Screening before Thoracic Surgery during COVID-19 Pandemic: A Multicenter Retrospective Study

“…When used as a screening tool in identifying COVID-19, CT scan demonstrated a sensitivity of 68.4% and specifcity of 88% [30]. According to this study, several reports showed no additional beneft in adding CT scan to other screenings such as anamnestic questionnaire and RT-PCR [5,7,24,31], and a low positive yield in asymptomatic preoperative patients [7,8,32,33]. In particular, the SCOUT multicentric study demonstrated a positive yield of 0.7% (95%CI: 0.2-1.1) for chest CT scan, 1.1% (95%CI: 0.6-1.7) for RT-PCR, and 1.5% (95%CI: 0.8-2) using a combination of chest CT scan and RT-PCR, highlighting the limited value of adding chest CT scan to RT-PCR screening [7].…”

A Pictorial Review of the Role of Imaging in the Detection, Management, Histopathological Correlations, and Complications of COVID-19 Pneumonia

“…However, patients with RT-PCR-confirmed COVID-19 may also have normal CT findings, especially in the first 3 days after the onset of symptoms [ 28 , 104 ]. Chest CT can also reveal lung alterations in asymptomatic or mildly symptomatic patients [ 112 , 113 ], but its use as a screening tool is not validated due to the amount of radiation and the possibility of normal findings [ 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 114 ]. CT is also used during short-term follow-up of COVID-19 for clinical decision making to monitor the course of pneumonia in hospitalized patients, and it can also be used in symptomatic patients for long-term follow-up, as it can reveal late lung alterations [ 29 , 108 , 113 , 114 , 115 , 116 ].…”

Outbreak of Health Care-associated Novel Coronavirus (SARS-coV-2) COVID-19 infections in the Spring of 2020

“…Mental healthcare is also an important issue for COV- A COVID-19 Clinical Trial/Clinical Research Task Force comprising mainly members from the Clinical and Translational Research Center was established to support the safety and rapid implementation of large numbers of observational studies, specific clinical studies and clinical trials related to COVID-19. [2][3][4][5][6][7] A Keio COVID-19 Registry was also established to unify multiple studies to develop a database that could provide large amounts of research data in the future. A large-scale nationwide team was established to study genomic susceptibility of the host genome focusing on the low number of serious and fatal cases among Japanese patients.…”