Integrated model for COVID-19 diagnosis based on computed tomography artificial intelligence, and clinical features: a multicenter cohort study.

Background: We developed and validated a machine learning diagnostic model for the novel coronavirus (COVID-19) disease, integrating artificial-intelligence-based computed tomography (CT) imaging and clinical features. Methods: We conducted a retrospective cohort study in 11 Japanese tertiary care facilities that treated COVID-19 patients. Participants were tested using both real-time reverse transcription polymerase chain reaction (RT-PCR) and chest CTs between January 1 and May 30, 2020. We chronologically split the dataset in each hospital into training and test sets, containing patients in a 7:3 ratio. A Light Gradient Boosting Machine model was used for the analysis. Results: A total of 703 patients were included, and two models-the full model and the A-blood model-were developed for their diagnosis. The A-blood model included eight variables (the Ali-M3 confidence, along with seven clinical features of blood counts and biochemistry markers). The areas under the receiver-operator curve of both models [0.91, 95% confidence interval (CI): 0.86 to 0.95 for the full model and 0.90, 95% CI: 0.86 to 0.94 for the A-blood model] were better than that of the Ali-M3 confidence (0.78, 95% CI: 0.71 to 0.83) in the test set. Conclusions: The A-blood model, a COVID-19 diagnostic model developed in this study, combines machine-learning and CT evaluation with blood test data and performs better than the Ali-M3 framework existing for this purpose. This would significantly aid physicians in making a quicker diagnosis of COVID-19.

Efficacy of awake prone positioning for severe illness coronavirus disease 2019 patients: a propensity score‐adjusted cohort study

Aim Awake prone positioning (PP) in patients with coronavirus disease 2019 (COVID‐19) can improve oxygenation. However, evidence showing that it can prevent intubation is lacking. This study investigated the efficacy of awake PP in patients with COVID‐19 who received remdesivir, dexamethasone, and anticoagulant therapy. Methods This was a two‐center cohort study. Patients admitted to the severe COVID‐19 patient unit were included. The primary outcome was the intubation rate and secondary outcome was length of stay in the severe COVID‐19 unit. After propensity score adjustment, we undertook multivariable regression to calculate the estimates of outcomes between patients who received awake PP and those who did not. Results Overall, 108 patients were included (54 [50.0%] patients each who did and did not undergo awake PP), of whom 25 (23.2%) were intubated (with awake PP, 5 [9.3%] vs. without awake PP, 20 [37.0%];P < 0.01). The median length of stay in the severe COVID‐19 unit did not significantly differ (with awake PP, 5 days vs. without awake PP, 5.5 days;P = 0.68). After propensity score adjustment, those who received awake PP had a lower intubation rate than those who did not (odds ratio, 0.22;95% confidence interval, 0.06–0.85;P = 0.03). Length of stay in the severe COVID‐19 patient unit did not differ significantly (adjusted percentage difference, −24.4%;95% confidence interval, −56.3% to 30.8%;P = 0.32). Conclusion Awake PP could be correlated with intubation rate in patients with COVID‐19 who are receiving remdesivir, dexamethasone, and anticoagulant therapy. This study aimed to investigate the efficacy of awake prone positioning (PP) for patients with coronavirus disease 2019 (COVID‐19) using remdesivir, dexamethasone, and anticoagulation therapy. We undertook a two‐center propensity score‐adjusted cohort study in Japan from July 2020 to February 2021. We showed that awake PP could be correlated with intubation rate in patients with acute respiratory failure and COVID‐19.

Intensive care burden of COVID-19 in tertiary care hospitals during the first year of outbreak in Kawasaki City, Japan: A retrospective cohort study.

INTRODUCTION: This study aimed to describe the changes in the intensive care burden of coronavirus disease 2019 (COVID-19) during the first year of outbreak in Japan. METHODS: This retrospective cohort study included COVID-19 patients who received mechanical ventilation (MV) support in two designated hospitals for critical patients in Kawasaki City. We compared the lengths of MV and stay in the intensive care unit (ICU) or high care unit (HCU) according to the three epidemic waves. We calculated in-hospital mortality rates in patients with or without MV. RESULTS: The median age of the sample was 65.0 years, and 22.7% were women. There were 37, 29, and 62 patients in the first (W1), second (W2), and third waves (W3), respectively. Systemic steroids, remdesivir, and prone positioning were more frequent in W2 and W3. The median length of MV decreased from 18.0 days in W1 to 13.0 days in W3 (P = 0.019), and that of ICU/HCU stay decreased from 22.0 days in W1 to 15.5 days in W3 (P = 0.027). The peak daily number of patients receiving MV support was higher at 18 patients in W1, compared to 8 and 15 patients in W2 and W3, respectively. The mortality rate was 23.4%, which did not significantly change (P = 0.467). CONCLUSIONS: The lengths of MV and ICU/HCU stay per patient decreased over time. Despite an increase in the number of COVID-19 patients who received MV in W3, this study may indicate that the intensive care burden during the study period did not substantially increase.

Functional decline in hospitalized older patients with coronavirus disease 2019: a retrospective cohort study.

BACKGROUND: This study aimed to determine the frequency of functional decline and to identify the factors related to a greater risk of functional decline among hospitalized older patients with coronavirus disease 2019 (COVID-19). METHODS: We reviewed the medical records of patients aged over 65 years who were admitted to a tertiary care hospital for COVID-19 over 1 year from February 2020. We evaluated the proportion of functional decline, which was defined as a decrease in the Barthel Index score from before the onset of COVID-19 to discharge. Multivariable logistic regression analyses were performed to evaluate the associations between the demographic and clinical characteristics of patients at admission and a greater risk of functional decline. Two sensitivity analyses with different inclusion criteria were performed: one in patients without very severe functional decline before the onset of COVID-19 (i.e., limited to those with Barthel Index score ≥ 25), and the other with a composite outcome of functional decline and death at discharge. RESULTS: The study included 132 patients with COVID-19; of these, 72 (54.5%) developed functional decline. The severity of COVID-19 did not differ between patients with functional decline and those without (P = 0.698). Factors associated with a greater risk of functional decline included female sex (adjusted odds ratio [aOR], 3.14; 95% confidence interval [CI], 1.25 to 7.94), Barthel Index score < 100 before the onset of COVID-19 (aOR, 13.73; 95% CI, 3.29 to 57.25), and elevation of plasma D-dimer level on admission (aOR, 3.19; 95% CI, 1.12 to 9.07). The sensitivity analyses yielded similar results to those of the main analysis. CONCLUSIONS: Over half of the older patients who recovered from COVID-19 developed functional decline at discharge from a tertiary care hospital in Japan. Baseline activities of daily living impairment, female sex, and elevated plasma D-dimer levels at admission were associated with a greater risk of functional decline.

Accuracy of deep learning-based computed tomography diagnostic system for COVID-19: A consecutive sampling external validation cohort study.

Ali-M3, an artificial intelligence program, analyzes chest computed tomography (CT) and detects the likelihood of coronavirus disease (COVID-19) based on scores ranging from 0 to 1. However, Ali-M3 has not been externally validated. Our aim was to evaluate the accuracy of Ali-M3 for detecting COVID-19 and discuss its clinical value. We evaluated the external validity of Ali-M3 using sequential Japanese sampling data. In this retrospective cohort study, COVID-19 infection probabilities for 617 symptomatic patients were determined using Ali-M3. In 11 Japanese tertiary care facilities, these patients underwent reverse transcription-polymerase chain reaction (RT-PCR) testing. They also underwent chest CT to confirm a diagnosis of COVID-19. Of the 617 patients, 289 (46.8%) were RT-PCR-positive. The area under the curve (AUC) of Ali-M3 for predicting a COVID-19 diagnosis was 0.797 (95% confidence interval: 0.762‒0.833) and the goodness-of-fit was P = 0.156. With a cut-off probability of a diagnosis of COVID-19 by Ali-M3 set at 0.5, the sensitivity and specificity were 80.6% and 68.3%, respectively. A cut-off of 0.2 yielded a sensitivity and specificity of 89.2% and 43.2%, respectively. Among the 223 patients who required oxygen, the AUC was 0.825. Sensitivity at a cut-off of 0.5% and 0.2% was 88.7% and 97.9%, respectively. Although the sensitivity was lower when the days from symptom onset were fewer, the sensitivity increased for both cut-off values after 5 days. We evaluated Ali-M3 using external validation with symptomatic patient data from Japanese tertiary care facilities. As Ali-M3 showed sufficient sensitivity performance, despite a lower specificity performance, Ali-M3 could be useful in excluding a diagnosis of COVID-19.

A fatal case of extensive gastrointestinal necrosis due to portal and mesenteric vein thrombosis in the post-acute phase of COVID-19.

Portal vein thrombosis (PVT) is considered a relatively rare thrombotic complication in coronavirus disease 2019 (COVID-19). Most reported cases of PVT develop within 2 weeks from COVID-19 onset. We report a fatal case of extensive gastrointestinal necrosis due to portal and mesenteric vein thrombosis approximately 6 weeks after the onset of critical COVID-19. Excessive elevation of his plasma D-dimer level had continued for weeks during the hospitalization contrary with improvement of respiratory failure. Thrombotic complication should be cautiously paid attention even in the post-acute phase of COVID-19, especially in patients with persistent elevation of plasma D-dimer level.

COVID-19 and Fatal Sepsis Caused by Hypervirulent Klebsiella pneumoniae, Japan, 2020.

A patient in Japan with coronavirus disease and hypervirulent Klebsiella pneumoniae K2 sequence type 86 infection died of respiratory failure. Bacterial and fungal co-infections caused by region-endemic pathogens, including hypervirulent K. pneumoniae in eastern Asia, should be included in the differential diagnosis of coronavirus disease patients with acutely deteriorating condition.

Clinical course of 2019 novel coronavirus disease (COVID-19) in individuals present during the outbreak on the Diamond Princess cruise ship.

We investigated the clinical course of individuals with 2019 novel coronavirus disease (COVID-19) who were transferred from the Diamond Princess cruise ship to 12 local hospitals. The conditions and clinical courses of patients with pneumonia were compared with those of patients without pneumonia. Among 70 patients (median age: 67 years) analyzed, the major symptoms were fever (64.3%), cough (54.3%), and general fatigue (24.3%). Forty-three patients (61.4%) had pneumonia. Higher body temperature, heart rate, and respiratory rate as well as higher of lactate dehydrogenase (LDH), aspartate aminotransferase (AST), and C-reactive protein (CRP) levels and lower serum albumin level and lymphocyte count were associated with the presence of pneumonia. Ground-glass opacity was found in 97.7% of the patients with pneumonia. Patients were administered neuraminidase inhibitors (20%), lopinavir/ritonavir (32.9%), and ciclesonide inhalation (11.4%). Mechanical ventilation and veno-venous extracorporeal membrane oxygenation was performed on 14 (20%) and 2 (2.9%) patients, respectively; two patients died. The median duration of intubation was 12 days. The patients with COVID-19 transferred to local hospitals during the outbreak had severe conditions and needed close monitoring. The severity of COVID-19 depends on the presence of pneumonia. High serum LDH, AST and CRP levels and low serum albumin level and lymphocyte count were found to be predictors of pneumonia. It was challenging for local hospitals to admit and treat these patients during the outbreak of COVID-19. Assessment of severity was crucial to manage a large number of patients.

[Clinical Course of 11 Cases of SARS-CoV-2 Infection Occurred in A Large Cruise Ship�E�Factors Associated with Severity and Prolonged Hospitalization]

The number of the patients with coronavirus disease 2019 (COVID-19) is increasing, and shortage of hospital beds for these patients is a cause for serious concern. Here, we report the clinical course of 11 patients who were admitted to our hospital with COVID-19 that developed during their quarantine period in a large cruise ship, and discuss the factors associated with the disease severity and length of hospitalization. The median age of the 11 patients was 62 years, and 36% were men. The disease severity was mild in 7 patients, moderate in 4 patients, and severe in none of the patients. The median time from symptom onset to disease remission was 13 days for patients with moderately severe disease, and 7 days for patients with mild disease. The median interval from symptom onset to confirmation of the first negative result of PCR was 16 days for patients with moderately severe disease, and 14 days for patients with mild disease. The median time from symptom onset to discharge was 22.5 days for patients with moderately severe disease cases, and 16 days for patients with mild disease. Some patients needed prolonged hospitalization because of persistently positive results of PCR even after remission of symptoms. Comparison between the patient groups with moderately severe disease and mild disease showed that the patients with moderately severe disease were older and had higher serum ferritin and serum amyloid protein (SAA) levels than the patients with mild disease. Even in patients with mild to moderate COVID-19, two to three weeks were required from symptom onset to confirmation of the first negative result of PCR, and this was one of the major factors for prolonged hospitalization. The serum ferritin levels and SAA levels might be predictors of the disease severity.