Computerised tomography (CT) findings and COVID-19 Infection (multiple reviews)
What is this? Many research articles have been published about diagnostic features for COVID-19 infection, such as those found with computerised tomography (CT) imaging of the chest. Several rapid reviews are summarised here. More details on each review, including citations and links to the full text, are available further down this web page.
What was found: At the time of these reviews, the included studies showed that chest CT imaging has high sensitivity but low specificity for diagnosing COVID-19 infection and the reviews mostly recommended that chest CT not be used as a first-line tool for this diagnosis. However, the Shao review (search done on 7 June 2020) concluded that CT is capable of detecting COVID-19 infection earlier in the infectious course than RT-PCR laboratory tests and concluded that, among surgical patients, chest CT be considered as an additional diagnostic measure before surgery for detecting COVID-19 infection in patients who are symptomatic but have tested negative with RT-PCR.
In general, these reviews found that Ground-Glass Opacities (GGO) and consolidation was often reported by CT and pathological signs of COVID-19 were often found in multiple lung lobes and bilaterally. The Xu (search done on 31 March 2020) and Lv reviews (search done on 31 March 2020) reported that lower lobes were frequently affected, and the Wan review (search done on 15 March 2020) reported that most patients in the studies in their review had CT abnormalities noted in the right lower lobe.
Most reviews reported that normal chest CT findings were rarely reported but the Sun review (search done on 31 March 2020) found that normal CT imaging was reported, particular among asymptomatic patients and those in the early stages of infection.
Several reviews reported that chest CT is good at detecting COVID-19 imaging abnormalities when symptomatic infection is present (sensitivity), particularly in severe epidemic areas. But the Lv review (search done on 31 March 2020) noted that sensitivity was reduced in children. The Xu review (search done on 31 March 2020) noted that chest CT has high sensitivity for patients with an initial false-negative COVID-19 result.
The reviews found that chest CT has poor specificity for COVID-19 infection. For example, the Sun review (search done on 31 March 2020) reported that the CT findings typically observed with COVID-19 are also observed in other viral pneumonias and the Salameh review (search done on 5 May 2020) reported that using CT findings to diagnose COVID-19 may result in similar proportions of “positive” results in patients with and without COVID-19.
The Park review (search done on 17 March 2020) concluded that there was insufficient evidence to support using CT for COVID-19 screening and the Adams review (search done on 12 April 2020) concluded that their findings did not support using CT imaging for screening people with no symptoms of COVID-19.
What are the reviews:
Citation: Adams HJ, Kwee TC, Yakar D, et al. Systematic Review and Meta-Analysis on the Value of Chest CT in the Diagnosis of Coronavirus Disease (COVID-19): Sol Scientiae, Illustra Nos. American Journal of Roentgenology. 2020 Dec:215(6):1342-50.
In this rapid review, the authors searched for studies on the diagnostic performance of chest CT in detecting COVID-19. They did not restrict their searches by date, type or language of publication and did the search on 12 April 2020. They included 6 studies (total: 1431 participants), from China (4 studies), Italy (1) and Japan (1).
Citation: Kim H, Hong H, Yoon SH. Diagnostic performance of CT and reverse transcriptase-polymerase chain reaction for coronavirus disease 2019: a meta-analysis. Radiology. 2020:296(3):E145-55.
In this rapid review, the authors searched for studies of chest CT scans or reverse transcriptase-polymerase chain reaction (RT-PCR) assays as diagnostic tests for COVID-19 infection. They restricted their searches to articles published between 1 December 2019 and 16 March 2020 and did the search on 3 April 2020. They included 68 articles.
Citation: Lv M, Wang M, Yang N, et al. Chest computed tomography for the diagnosis of patients with coronavirus disease 2019 (COVID-19): a rapid review and meta-analysis. Annals of Translational Medicine 2020;8(10):622
In this rapid review, the authors searched for observational studies of the sensitivity of chest CT for diagnosing COVID-19 infection. They restricted their searches to publications in English and Chinese up to 31 March 2020. They included 103 studies (total: 5673 patients), with most studies from China (95) and one study from each of Germany, Korea, Italy and the cruise ship “Diamond Princess”. They assessed all included studies as low-quality evidence.
Citation: Park JH, Jang W, Kim SW, et al. The clinical manifestations and chest computed tomography findings of coronavirus disease 2019 (COVID-19) patients in China: a proportion meta-analysis. Clinical and Experimental Otorhinolaryngology. 2020 May;13(2):95-105.
In this rapid review, the authors searched for observational studies of CT findings in COVID-19 patients. They restricted their searches to articles published in English that included ≥4 patients and did the search on 17 March 2020. They included 4 studies from Wuhan, China and 5 studies from elsewhere in China (total: 627 participants). They assessed all included studies as low-quality evidence and noted marked variation between studies.
Citation: Salameh J-P, Leeflang MMG, Hooft L, et al. Thoracic imaging tests for the diagnosis of COVID‐19. Cochrane Database of Systematic Reviews. 2020;(9):CD013639.
In this Cochrane living review, the authors searched for studies comparing the diagnostic accuracy of chest imaging versus laboratory-based PCR tests in people with confirmed or suspected COVID-19. They did not restrict their searches by language of publication and did the search for this version of the review on 5 May 2020. They included studies assessing CT scans, chest X-rays and chest ultrasound investigations. They included 84 studies, of which most (78) assessed CT scans.
Citation: Shao JM, Ayuso SA, Deerenberg EB, et al. A systematic review of CT chest in COVID‐19 diagnosis and its potential application in a surgical setting. Colorectal disease. 2020 Sep;22(9):993-1001.
In this rapid review, the authors searched for studies assessing the sensitivity and utility of chest CT imaging in diagnosing COVID-19 infection, compared with RT-PCR testing, with a particular emphasis on surgical settings. They did not restrict their searches by language of publication and searched up to 7 June 2020. They included 20 studies.
Citation: Sun Z, Zhang N, Li Y, et al. A systematic review of chest imaging findings in COVID-19. Quantitative Imaging in Medicine and Surgery. 2020 May;10(5):1058-79.
In this rapid review, the authors searched for research on the clinical characteristics and chest imaging features of patients with COVID-19. They restricted their searches to articles published in English and searched up to 31 March 2020. They identified 55 studies from China (and included 25 of these in a meta-analysis). 52 included studies assessed the role of CT imaging in COVID-19 diagnosis.
Citation: Wan S, Li M, Ye Z, et al. CT manifestations and clinical characteristics of 1115 patients with coronavirus disease 2019 (COVID-19): A systematic review and meta-analysis. Academic Radiology. 2020 Jul 1;27(7):910-21.
In this systematic review, the authors searched for observational studies assessing CT features, clinical features and laboratory results of patients with confirmed COVID-19 infection. They restricted their searches to articles published between 1 January 2019 and 15 March 2020. They included 14 observational studies (total: 1115 participants), which were all from China and assessed these as ‘fair’ quality.
Citation: Xu B, Xing Y, Peng J, et al. Chest CT for detecting COVID-19: a systematic review and meta-analysis of diagnostic accuracy. European Radiology. 2020 Oct:30(10):5720-7.
In this rapid review, the authors searched for studies of the diagnostic test accuracy of chest CT for detecting COVID-19 infection. They did not restrict their searches by language of publication and included studies with ≥30 patients, published up to 31 March 2020. They included 16 studies (total: 3186 patients), which were all from China and noted marked variation between studies.
Citation: Zhu J, Zhong Z, Li H, et al. CT imaging features of 4121 patients with COVID-19: a meta-analysis. Journal of Medical Virology 2020 Jul;92(7):891-902.
In this rapid review, the authors searched for observational studies examining CT imaging features of COVID-19 patients. They did not restrict their searches by language of publication and included studies with ≥30 patients published between 1 January 2020 and 16 March 2020. They included 34 observational studies (total: 4121 participants), which were conducted in China, and assessed these as high-quality observational studies.
Other reviews of this topic
Citation: Altmayer S, Zanon M, Pacini GS, et al. Comparison of the Computed Tomography Findings in COVID-19 and Other Viral Pneumonia in Immunocompetent Adults: A Systematic Review and Meta-Analysis. European Radiology 2020 Dec; 30(12): 6485-96.