Performance Evaluation of the Roche Cobas 5800 HBV and HCV Tests: Comparison of the 200 and 500 µL Protocols.

Background: Clinical management of patients infected with hepatitis B virus (HBV) or hepatitis C virus (HCV) relies on the viral load (VL). The Cobas 5800 system (Roche Diagnostics) can determine VLs in 200 and 500 µL samples, but the performance of each protocol has not been compared. We evaluated the performance of both protocols for the HBV and HCV tests. Methods: Precision and linearity were verified using commercial panels. Probit analyses were used to determine limits of detection (LoDs). The results obtained with 336 samples were compared using the 200 and 500 µL protocols. Data from 6,737 retrospective HBV and 768 HCV samples were compared to estimate the effects of the different LoDs on the diagnostic results of the protocols. Correlations between protocols were tested with Spearman's rank correlation coefficients (rho). Results: The precision and linearity of both protocols were verified. The LoDs for the 200 and 500 µL protocols were 6.5 and 2.7 IU/mL for HBV and 29.7 and 8.2 IU/mL for HCV, respectively. The agreement between the protocols ranged from 0.8 to 1.0. The results obtained with the HBV and HCV tests showed a strong correlation (rho=0.994). Only 0.4% of HBV and 0.4% of HCV test results were affected by the LoDs of the 200 µL protocol. Conclusions: The Cobas 5800 200 and 500 µL protocols for the HBV DNA and HCV RNA tests demonstrated excellent performance. These findings establish the 200 µL protocol as a new option for low-volume samples, especially for pediatric and difficult-to-bleed patients.

Correction: Deep Learning With Chest Radiographs for Making Prognoses in Patients With COVID-19: Retrospective Cohort Study.

[This corrects the article DOI: 10.2196/42717.].

Erratum: Correction of Affiliations in the Article "Establishment of a Nationwide Korean Imaging Cohort of Coronavirus Disease 2019".

This corrects the article on p. e413 in vol. 35, PMID: 33258333.

Monitoring AKT activity and targeting in live tissue and disease contexts using a real-time Akt-FRET biosensor mouse.

Aberrant AKT activation occurs in a number of cancers, metabolic syndrome, and immune disorders, making it an important target for the treatment of many diseases. To monitor spatial and temporal AKT activity in a live setting, we generated an Akt-FRET biosensor mouse that allows longitudinal assessment of AKT activity using intravital imaging in conjunction with image stabilization and optical window technology. We demonstrate the sensitivity of the Akt-FRET biosensor mouse using various cancer models and verify its suitability to monitor response to drug targeting in spheroid and organotypic models. We also show that the dynamics of AKT activation can be monitored in real time in diverse tissues, including in individual islets of the pancreas, in the brown and white adipose tissue, and in the skeletal muscle. Thus, the Akt-FRET biosensor mouse provides an important tool to study AKT dynamics in live tissue contexts and has broad preclinical applications.

Impact of the COVID-19 Pandemic on the Usage of Blood for Transfusions: A 2-Year Experience from a Tertiary Center in Korea.

The coronavirus disease (COVID-19) outbreak affected the utilization and management of blood products in hospitals. Blood shortages occurred owing to social distancing policies and reduction in blood donors. However, only a few studies examined whether these changes affected blood usage and transfusion patterns. We retrospectively reviewed blood component usage according to hospital departments and phases of surgery in transfused patients admitted between 1 March 2019 and 28 February 2021, in a single center in Anyang, Korea. We also analyzed the length of hospital stay and mortality to determine prognosis. In 2020, 32,050 blood components were transfused to 2877 patients, corresponding to 15.8% and 11.8% less than the rates in 2019, respectively. Postoperative usage of blood products significantly decreased in 2020 (3.87 ± 6.50) compared to 2019 (7.12 ± 21.71) (p = 0.047). The length of hospital stay of the patients who underwent postoperative transfusion in 2019 (n = 197) was 13.97 ± 11.95 days, which was not significantly different from that in 2020 (n = 167), i.e., 16.44 ± 17.90 days (p = 0.118). Further, 9 of 197 postoperative transfusion patients died in 2019, while 8 of 167 patients died in 2020 (p = 0.920). The COVID-19 pandemic resulted in limited blood supply and reduced postoperative transfusions; however, patient prognosis was not affected.

Sesquiterpene Lactones with Anti-Inflammatory Activity from the Halophyte Sonchus brachyotus DC.

There were five sesquiterpene lactones, belonging to the eudesmanolide class, isolated from the halophyte Sonchus brachyotus DC. The structures of the compounds were determined using spectroscopic methods, including 1D and 2D NMR spectra, MS data, and optical rotation values. Compounds 4 and 5 were characterized by the position of p-hydroxyphenylacetyl group in the sugar moiety. In the evaluation of anti-inflammatory effects on LPS-activated RAW264.7 macrophages, compound 1, 5α,6ßH-eudesma-3,11(13)-dien-12,6α-olide, potently suppressed the expression of iNOS and COS-2, as well as the production of TNF-α, IL-6, and IL-10. Treatment of 1 regulates the Nrf2/HO-1 pathway.

Deep Learning With Chest Radiographs for Making Prognoses in Patients With COVID-19: Retrospective Cohort Study.

BACKGROUND: An artificial intelligence (AI) model using chest radiography (CXR) may provide good performance in making prognoses for COVID-19. OBJECTIVE: We aimed to develop and validate a prediction model using CXR based on an AI model and clinical variables to predict clinical outcomes in patients with COVID-19. METHODS: This retrospective longitudinal study included patients hospitalized for COVID-19 at multiple COVID-19 medical centers between February 2020 and October 2020. Patients at Boramae Medical Center were randomly classified into training, validation, and internal testing sets (at a ratio of 8:1:1, respectively). An AI model using initial CXR images as input, a logistic regression model using clinical information, and a combined model using the output of the AI model (as CXR score) and clinical information were developed and trained to predict hospital length of stay (LOS) ≤2 weeks, need for oxygen supplementation, and acute respiratory distress syndrome (ARDS). The models were externally validated in the Korean Imaging Cohort of COVID-19 data set for discrimination and calibration. RESULTS: The AI model using CXR and the logistic regression model using clinical variables were suboptimal to predict hospital LOS ≤2 weeks or the need for oxygen supplementation but performed acceptably in the prediction of ARDS (AI model area under the curve [AUC] 0.782, 95% CI 0.720-0.845; logistic regression model AUC 0.878, 95% CI 0.838-0.919). The combined model performed better in predicting the need for oxygen supplementation (AUC 0.704, 95% CI 0.646-0.762) and ARDS (AUC 0.890, 95% CI 0.853-0.928) compared to the CXR score alone. Both the AI and combined models showed good calibration for predicting ARDS (P=.079 and P=.859). CONCLUSIONS: The combined prediction model, comprising the CXR score and clinical information, was externally validated as having acceptable performance in predicting severe illness and excellent performance in predicting ARDS in patients with COVID-19.

Phragmites australis (Cav.) Trin. ex Steud. Extract Induces Apoptosis-like Programmed Cell Death in Acanthamoeba castellanii Trophozoites.

Acanthamoeba keratitis (AK) is an infectious ocular disease which is difficult to diagnose correctly and cure. Development of an effective and safe therapeutic drug for AK is needed. Our preliminary screening of more than 200 extracts from wild plants collected in Korea suggested the potential amoebicidal activity of Phragmites australis (Cav.) Trin. ex Steud. extract (PAE) against Acanthamoeba species. Here, we aimed to analyze the amoebicidal activity of PAE on Acanthamoeba and its underlying amoebicidal mechanism. PAE induced amoebicidal activity against both A. castellanii and A. polyphaga trophozoites, while it showed low cytotoxicity in human corneal epithelial cells (HCE-2) and human retinal pigment epithelial cells (ARPE-19). Transmission electron microscopy analysis showed subcellular morphological changes, such as increased granules, abnormal mitochondria, and atypical cyst wall formation, in the PAE-treated A. castellanii. Fluorometric apoptosis assay and TUNEL assay revealed apoptosis-like programmed cell death (PCD) in the PAE-treated A. castellanii. The PAE treatment increased reactive oxygen species production and reduced mitochondrial membrane potential in the amoeba. The enhanced expression of autophagy-associated genes was also detected. These results suggested that PAE exerted a promising amoebicidal effect on A. castellanii trophozoites via the PCD pathway. PAE could be a potential candidate for developing a therapeutic drug for AK.

The First Case of Adult Granular Acute Lymphoblastic Leukemia with DNMT3A Mutation and Monosomy 7.

Granular acute lymphoblastic leukemia (ALL) is defined by the presence of intracytoplasmic granules in lymphoblastic blasts, mimicking acute myeloblastic leukemia. The disease is extremely rare in adults, and hence, the characteristics thereof are poorly understood. We report a case of a 70-year-old man diagnosed with granular ALL. Bone marrow examination showed blasts with azurophilic granules in the cytoplasm, but immunophenotyping showed B-ALL with aberrant expression of myeloid antigens CD13 and CD33. Karyotyping revealed monosomy 7, and targeted NGS showed DNMT3A mutation, which suggested poor prognosis. Despite conventional chemotherapy treatment, the patient did not achieve complete remission. He declined further chemotherapy treatment and was maintained on only supportive care. This is the first report of adult granular ALL with DNMT3A mutation and monosomy 7.

CT findings of COVID-19-associated pulmonary aspergillosis: a systematic review and individual patient data analysis.

PURPOSE: Common CT abnormalities of pulmonary aspergillosis represent a cavity with air-meniscus sign, nodule, mass, and consolidation having an angio-invasive pattern. This study aims to conduct a systematic review and an individual patient-level image analysis of CT findings of COVID-19-associated pulmonary aspergillosis (CAPA). METHODS: A systematic literature search was conducted to identify studies reporting CT findings of CAPA as of January 7, 2021. We summarized study-level clinical and CT findings of CAPA and collected individual patient CT images by inviting corresponding authors. The CT findings were categorized into four groups: group 1, typical appearance of COVID-19; group 2, indeterminate appearance of COVID-19; group 3, atypical for COVID-19 without cavities; and group 4, atypical for COVID-19 with cavities. In group 2, cases had only minor discrepant findings including solid nodules, isolated airspace consolidation with negligible ground-glass opacities, centrilobular micronodules, bronchial abnormalities, and cavities. RESULTS: The literature search identified 89 patients from 25 studies, and we collected CT images from 35 CAPA patients (mean age 62.4 ± 14.6 years; 21 men): group 1, thirteen patients (37.1%); group 2, eight patients (22.9%); group 3, six patients (17.1%); and group 4, eight patients (22.9%). Eight of the 14 patients (57.1%) with an atypical appearance had bronchial abnormalities, whereas only one (7.1%) had an angio-invasive fungal pattern. In the study-level analysis, cavities were reported in 12 of 54 patients (22.2%). CONCLUSION: CAPA can frequently manifest as COVID-19 pneumonia without common CT abnormalities of pulmonary aspergillosis. If abnormalities exist on CT images, CAPA may frequently accompany bronchial abnormalities.

Epidemiologic Trends of Thalassemia, 2006-2018: A Nationwide Population-Based Study.

Thalassemia is the most common form of hereditary anemia. Here, we aimed to investigate the 13-year trend of the epidemiologic profiles and risk of comorbidities in thalassemia using a nationwide population-based registry in Korea. Diagnosis of thalassemia, the comorbidities and transfusion events in patients with thalassemia were identified in the Korean National Health Insurance database, which includes the entire population. The prevalence of thalassemia increased from 0.74/100,000 in 2006 to 2.76/100,000 in 2018. Notably, the incidence rate has nearly doubled in the last 2 years from 0.22/100,000 in 2016 to 0.41/100,000 in 2018. The annual transfusion rate gradually decreased from 34.7% in 2006 to 20.6% in 2018. Transfusion events in patients with thalassemia were significantly associated with the risk of comorbidities (diabetes: odds ratio [OR] = 3.68, 95% confidence interval [CI] = 2.59-5.22; hypertension: OR = 3.06, 95% CI = 2.35-4.00; dyslipidemia: OR = 1.72, 95% CI = 1.22-2.43; atrial fibrillation: OR = 3.52, 95% CI = 1.69-7.32; myocardial infarction: OR = 3.02, 95% CI = 1.09-8.38; stroke: OR = 3.32, 95% CI = 2.05-5.36; congestive heart failure: OR = 2.83, 95% CI = 1.62-4.97; end-stage renal disease: OR = 3.25, 95% CI = 1.96-5.37). Early detection of comorbidities and timely intervention are required for the management of thalassemia.

Deep Learning-Based Automatic CT Quantification of Coronavirus Disease 2019 Pneumonia: An International Collaborative Study.

OBJECTIVE: We aimed to develop and validate the automatic quantification of coronavirus disease 2019 (COVID-19) pneumonia on computed tomography (CT) images. METHODS: This retrospective study included 176 chest CT scans of 131 COVID-19 patients from 14 Korean and Chinese institutions from January 23 to March 15, 2020. Two experienced radiologists semiautomatically drew pneumonia masks on CT images to develop the 2D U-Net for segmenting pneumonia. External validation was performed using Japanese (n = 101), Italian (n = 99), Radiopaedia (n = 9), and Chinese data sets (n = 10). The primary measures for the system's performance were correlation coefficients for extent (%) and weight (g) of pneumonia in comparison with visual CT scores or human-derived segmentation. Multivariable logistic regression analyses were performed to evaluate the association of the extent and weight with symptoms in the Japanese data set and composite outcome (respiratory failure and death) in the Spanish data set (n = 115). RESULTS: In the internal test data set, the intraclass correlation coefficients between U-Net outputs and references for the extent and weight were 0.990 and 0.993. In the Japanese data set, the Pearson correlation coefficients between U-Net outputs and visual CT scores were 0.908 and 0.899. In the other external data sets, intraclass correlation coefficients were between 0.949-0.965 (extent) and between 0.978-0.993 (weight). Extent and weight in the top quartile were independently associated with symptoms (odds ratio, 5.523 and 10.561; P = 0.041 and 0.016) and the composite outcome (odds ratio, 9.365 and 7.085; P = 0.021 and P = 0.035). CONCLUSIONS: Automatically quantified CT extent and weight of COVID-19 pneumonia were well correlated with human-derived references and independently associated with symptoms and prognosis in multinational external data sets.

Acute Promyelocytic Leukemia with a BCR-ABL1 Rearrangement in a Minor Clone.

Acute promyelocytic leukemia (APL) is a type of acute myeloid leukemia characterized by predominating abnormal promyelocytes with a PML-RARA rearrangement or a variant thereof. BCR-ABL1 rearrangement is an oncogenic event that is usually associated with chronic myeloid leukemia but also occurs in both acute lymphoblastic and acute myeloid leukemias and in healthy individuals. However, APL with concurrent PML-RARA and BCR-ABL1 rearrangements has rarely been reported. Herein, we describe a patient with APL exhibiting a BCR-ABL1 rearrangement in a minor clone and discuss the importance of evaluating this genetic alteration in terms of pathogenesis and treatment.

Clinical insights into hematologic malignancies and comparative analysis of molecular signatures of acute myeloid leukemia in different ethnicities using an artificial intelligence offering.

ABSTRACT: Next generation sequencing generates copious amounts of genomics data, causing manual interpretation to be laborious and non-scalable while remaining subjective (even for highly trained specialists). We evaluated the performance of the artificial intelligence-based offering Watson for Genomics (WfG), a variant interpretation platform, in hematologic malignancies for the first time.Next generation sequencing was performed for patients treated for various hematological malignancies at Hallym University Sacred Heart Hospital, South Korea, between December 2017 and August 2020 using a 54-gene panel. Both WfG and expert manual curation were used to evaluate the performance of WfG. Acute myeloid leukemia (AML) molecular profiles were compared between Koreans and other ethnic groups using a publicly available dataset.Seventy-seven patients were analyzed (AML: 45, myeloproliferative neoplasms: 12, multiple myeloma: 7, myelodysplastic syndromes: 6, and others: 7). The concordance between the manual and WfG interpretations of 35 variants in 11 random patients was 94%. Among all patients, WfG identified 39 (51%) with at least 1 clinically actionable therapeutic alteration (i.e., a variant targeted by a United States Food and Drug Administration [US FDA]-approved drug, off-label drug, or clinical trial). Moreover, 46% of these patients (18/39) had genes that were targeted by a US FDA-approved therapy. WfG identified diagnostic or prognostic insights in 65% of the patients with no targetable alterations. In those with AML, FLT3-internal tandem duplications or tyrosine kinase domain mutations were less frequent among Koreans than among Caucasians (6.7% vs 30.2%, P < .001) or Hispanics (6.7% vs 28.3%, P = .005), suggesting ethnic differences.Variant interpretation using WfG correlated well with manually curated expert opinions. WfG provided therapeutic insights (including variant-specific drugs and clinical trials that cannot easily be provided by expert manual curation), as well as diagnostic and/or prognostic information.

Optimizing metastatic-cascade-dependent Rac1 targeting in breast cancer: Guidance using optical window intravital FRET imaging.

Assessing drug response within live native tissue provides increased fidelity with regards to optimizing efficacy while minimizing off-target effects. Here, using longitudinal intravital imaging of a Rac1-Förster resonance energy transfer (FRET) biosensor mouse coupled with in vivo photoswitching to track intratumoral movement, we help guide treatment scheduling in a live breast cancer setting to impair metastatic progression. We uncover altered Rac1 activity at the center versus invasive border of tumors and demonstrate enhanced Rac1 activity of cells in close proximity to live tumor vasculature using optical window imaging. We further reveal that Rac1 inhibition can enhance tumor cell vulnerability to fluid-flow-induced shear stress and therefore improves overall anti-metastatic response to therapy during transit to secondary sites such as the lung. Collectively, this study demonstrates the utility of single-cell intravital imaging in vivo to demonstrate that Rac1 inhibition can reduce tumor progression and metastases in an autochthonous setting to improve overall survival.

Antibiofilm Activity of Phorbaketals from the Marine Sponge Phorbas sp. against Staphylococcus aureus.

Biofilm formation by Staphylococcus aureus plays a critical role in the persistence of chronic infections due to its tolerance against antimicrobial agents. Here, we investigated the antibiofilm efficacy of six phorbaketals: phorbaketal A (1), phorbaketal A acetate (2), phorbaketal B (3), phorbaketal B acetate (4), phorbaketal C (5), and phorbaketal C acetate (6), isolated from the Korean marine sponge Phorbas sp. Of these six compounds, 3 and 5 were found to be effective inhibitors of biofilm formation by two S. aureus strains, which included a methicillin-resistant S. aureus. In addition, 3 also inhibited the production of staphyloxanthin, which protects microbes from reactive oxygen species generated by neutrophils and macrophages. Transcriptional analyses showed that 3 and 5 inhibited the expression of the biofilm-related hemolysin gene hla and the nuclease gene nuc1.

Immunoglobulin gene rearrangement in Koreans with multiple myeloma: Clonality assessment and repertoire analysis using next-generation sequencing.

INTRODUCTION: We assessed the applicability of next-generation sequencing (NGS)-based IGH/IGK clonality testing and analyzed the repertoire of immunoglobulin heavy chain (IGH) or immunoglobulin kappa light chain (IGK) gene usage in Korean patients with multiple myeloma (MM) for the first time. METHODS: Fifty-nine bone marrow samples from 57 Korean patients with MM were analyzed, and NGS-based clonality testing that targeted the IGH and IGK genes was performed using IGH FR1 and IGK primer sets. RESULTS: Clonal IGH and IGK rearrangements were observed in 74.2% and 67.7% of samples from Korean patients with kappa-restricted MM, respectively (90.3% had one or both), and in 60.7% and 95.5% of samples from those with lambda-restricted MM, respectively (85.7% had one or both). In total, 88.1% of samples from Koreans with MM had clonal IGH and/or IGK rearrangement. Clonal rearrangement was not significantly associated with the bone marrow plasma cells as a proportion of all BM lymphoid cells. IGHV3-9 (11.63%) and IGHV4-31 (9.30%) were the most frequently reported IGHV genes and were more common in Koreans with MM than in Western counterparts. IGHD3-10 and IGHD3-3 (13.95% each) were the most frequent IGHD genes; IGHD3-3 was more common in Koreans with MM. No IGK rearrangement was particularly prevalent, but single IGKV-J rearrangements were less common in Koreans with kappa-restricted MM than in Western counterparts. IGKV4-1 was less frequent in Koreans regardless of light chain type. Otherwise, the usages of the IGH V, D, and J genes and of the IGK gene were like those observed in previous Western studies. CONCLUSION: NGS-based IGH/IGK clonality testing ought to be applicable to most Koreans with MM. The overrepresentation of IGHV3-9, IGHV4-31, and IGHD3-3 along with the underrepresentation of IGKV4-1 and the differences in IGK gene rearrangement types suggest the existence of ethnicity-specific variations in this disease.

A comparison of the analysis of 3 types of body fluids using the XN-350 hematology analyzer versus light microscopy assessment.

ABSTRACT: We evaluated the capacity of the XN-350 instrument to analyze 3 different types of body fluid samples under "body fluid mode."The performance of XN-350 was evaluated in terms of precision, carryover, limit of blank, limit of detection, limit of quantification, and linearity. Cell enumeration and differential data produced by the XN-350 were compared to manual chamber counting results in 63 cerebrospinal fluid (CSF), 51 ascitic fluid, and 51 pleural fluid (PF) samples. Comparisons between XN-350 versus Cytospin data were also performed in PF samples.The precision, carry-over, limit of blank, and linearity of the XN-350 were acceptable. The limits of detection for white blood cells (WBCs) and red blood cells were 1.0/µL, and 1,000.0/µL, respectively; the corresponding limits of quantitation (LOQs) were 5.0/µL and 2,000.0/µL, respectively. The XN-350's cell enumeration and differential counting correlated well with those of manual chamber counting for all 3 sample types (except for differential counting in CSF samples), particularly parameters involving monocytes (r = 0.33) and mononuclear cells (MO- body fluid [BF]; r = 0.26), as well as total cell (TC-BF) enumeration (r = 0.50) and WBC-BF (r = 0.50) in PF samples. The MO-BF in CSF samples differed significantly from manual chamber counting results, but neither TC-BF nor WBC-BF in PF samples did. The XN-350 also showed good correlations with Cytospin analyses for differential counting of neutrophils, lymphocytes, and monocytes in PF samples. The differential counting of eosinophils via the XN-350 and Cytospin were not significantly correlated, but the difference between them was not significant.The XN-350 is an acceptable alternative to manual fluid analysis. Samples with low cellularity around the LOQ should be checked manually. Moreover, manual differential counting should be performed on CSF samples, particularity those with low cell numbers.

Factors Associated with Worsening Oxygenation in Patients with Non-severe COVID-19 Pneumonia.

BACKGROUND: This study aimed to determine the parameters for worsening oxygenation in non-severe coronavirus disease 2019 (COVID-19) pneumonia. METHODS: This retrospective cohort study included cases of confirmed COVID-19 pneumonia in a public hospital in South Korea. The worsening oxygenation group was defined as that with SpO2 ≤94% or received oxygen or mechanical ventilation (MV) throughout the clinical course versus the non-worsening oxygenation group that did not experience any respiratory event. Parameters were compared, and the extent of viral pneumonia from an initial chest computed tomography (CT) was calculated using artificial intelligence (AI) and measured visually by a radiologist. RESULTS: We included 136 patients, with 32 (23.5%) patients in the worsening oxygenation group; of whom, two needed MV and one died. Initial vital signs and duration of symptoms showed no difference between the two groups; however, univariate logistic regression analysis revealed that a variety of parameters on admission were associated with an increased risk of a desaturation event. A subset of patients was studied to eliminate potential bias, that ferritin ≥280 µg/L (p=0.029), lactate dehydrogenase ≥240 U/L (p=0.029), pneumonia volume (p=0.021), and extent (p=0.030) by AI, and visual severity scores (p=0.042) were the predictive parameters for worsening oxygenation in a sex-, age-, and comorbid illness-matched case-control study using propensity score (n=52). CONCLUSION: Our study suggests that initial CT evaluated by AI or visual severity scoring as well as serum markers of inflammation on admission are significantly associated with worsening oxygenation in this COVID-19 pneumonia cohort.

Chest CT Findings of COVID-19 Patients with Mild Clinical Symptoms at a Single Hospital in Korea.

Purpose: To retrospectively evaluate the chest computed tomography (CT) findings of coronavirus disease 2019 (COVID-19) in patients with mild clinical symptoms at a single hospital in South Korea. Materials and Methods: CT scans of 87 COVID-19 patients [43 men and 44 women; median age: 41 years (interquartile range: 26.1-51.0 years)] with mild clinical symptoms (fever < 38℃ and no dyspnea) were evaluated. Results: CT findings were normal in 39 (44.8%) and abnormal in 48 (55.2%) patients. Among the 48 patients with lung opacities, 17 (35.4%) had unilateral disease and 31 (64.6%) had bilateral disease. One (2.1%) patient showed subpleural distribution, 9 (18.8%) showed peribronchovascular distribution, and 38 (79.2%) showed subpleural and peribronchovascular distributions. Twenty-two (45.8%) patients had pure ground-glass opacities (GGOs) with no consolidation, 17 (35.4%) had mixed opacities dominated by GGOs, and 9 (18.8%) had mixed opacities dominated by consolidation. No patients demonstrated consolidation without GGOs. Conclusion: The most common CT finding of COVID-19 in patients with mild clinical symptoms was bilateral multiple GGO-dominant lesions with subpleural and peribronchovascular distribution and lower lung predilection. The initial chest CT of almost half of COVID-19 patients with mild clinical symptoms showed no lung parenchymal lesions. Compared to relatively severe cases, mild cases were more likely to manifest as unilateral disease with pure GGOs or GGO-dominant mixed opacities and less likely to show air bronchogram.