Background The association of pulmonary embolism (PE) with deep vein thrombosis (DVT) in patients with coronavirus disease 2019 (COVID-19) remains unclear, and the diagnostic accuracy of D -dimer tests for PE is unknown. Purpose To conduct meta-analysis of the study-level incidence of PE and DVT and to evaluate the diagnostic accuracy of D -dimer tests for PE from multicenter individual patient data. Materials and Methods A systematic literature search identified studies evaluating the incidence of PE or DVT in patients with COVID-19 from January 1, 2020, to June 15, 2020. These outcomes were pooled using a random-effects model and were further evaluated using metaregression analysis. The diagnostic accuracy of D -dimer tests for PE was estimated on the basis of individual patient data using the summary receiver operating characteristic curve. Results Twenty-seven studies with 3342 patients with COVID-19 were included in the analysis. The pooled incidence rates of PE and DVT were 16.5% (95% CI: 11.6, 22.9; I 2 = 0.93) and 14.8% (95% CI: 8.5, 24.5; I 2 = 0.94), respectively. PE was more frequently found in patients who were admitted to the intensive care unit (ICU) (24.7% [95% CI: 18.6, 32.1] vs 10.5% [95% CI: 5.1, 20.2] in those not admitted to the ICU) and in studies with universal screening using CT pulmonary angiography. DVT was present in 42.4% of patients with PE. D -dimer tests had an area under the receiver operating characteristic curve of 0.737 for PE, and D -dimer levels of 500 and 1000 μg/L showed high sensitivity (96% and 91%, respectively) but low specificity (10% and 24%, respectively). Conclusion Pulmonary embolism (PE) and deep vein thrombosis (DVT) occurred in 16.5% and 14.8% of patients with coronavirus disease 2019 (COVID-19), respectively, and more than half of patients with PE lacked DVT. The cutoffs of D -dimer levels used to exclude PE in preexisting guidelines seem applicable to patients with COVID-19. © RSNA, 2020 Supplemental material is available for this article. See also the editorial by Woodard in this issue.

This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Intestinal ischemia in the COVID-19 era To the editor From the end of December, the world is facing the threat of a new zoonosis caused by Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS CoV-2) which gave rise to a pandemic which is currently ongoing. The Bergamo province has been one of the most affected regions worldwide with an increase in the mortality rate in the first trimester of 2020 of + 568% [1] if compared with the first trimester of the previous four years (2015-2019). Papa Giovanni XXIII Hospital was the most affected structure with over 20 0 0 admission for COVID-19 to date [2]. We describe a case of fatal intestinal infarction whit a difficult diagnosis, which was made possible throughout by using innovative technique. A 62-year-old unconscious man was admitted to the Emergency Department of Papa Giovanni XXIII Hospital (Bergamo, Italy) with severe hypotension during the month of April 2020. The recent medical history reported by phone from his wife included three days of abdominal pain and bilious vomiting. The patient's main comorbidities were obesity, arterial hypertension, diabetes mellitus type 2 and hepatic cirrhosis (non-alcoholic steatohepatitis + hepatitis B). Blood tests revealed an increase in the blood

No abstract

Aim Coronavirus disease (COVID‐19) is characterized by pneumonia with secondary damage to multiple organs including the liver. Liver injury (elevated alanine aminotransferase [ALT] and aspartate aminotransferase [AST]) often correlates with disease severity in COVID‐19 patients. The aim of this study is to identify pathological microthrombi in COVID‐19 patient livers by correlating their morphology with liver injury, and examine hyperfibrinogenemia and von Willebrand factor (vWF) as mechanisms of their formation. Methods Forty‐three post‐mortem liver biopsy samples from COVID‐19 patients were obtained from Papa Giovanni XXIII Hospital in Bergamo, Italy. Three morphological features of microthrombosis (sinusoidal erythrocyte aggregation [SEA], platelet microthrombi [PMT], and fibrous thrombi) were evaluated. Results We found liver sinusoidal microthrombosis in 23 COVID‐19 patients (53%) was associated with a higher serum ALT and AST level compared to those without (ALT: 10‐fold, p = 0.04; AST: 11‐fold, p = 0.08). Of 43 livers, PMT and SEA were observed in 14 (33%) and 19 (44%) cases, respectively. Fibrous thrombi were not observed. Platelet microthrombi were associated with increased ALT (p < 0.01), whereas SEA was not (p = 0.73). In COVID‐19 livers, strong vWF staining in liver sinusoidal endothelial cells was associated with significantly increased platelet adhesion (1.7‐fold, p = 0.0016), compared to those with weak sinusoidal vWF (2‐fold, p < 0.0001). Sinusoidal erythrocyte aggregation in 19 (83%) liver samples was mainly seen in zone 2. Livers with SEA had significantly higher fibrinogen (1.6‐fold, p = 0.031) compared to those without SEA in COVID‐19 patients. Conclusions Liver PMT is a pathologically important thrombosis associated with liver injury in COVID‐19, while SEA is a unique morphological feature of COVID‐19 patient livers. Sinusoidal vWF and hyperfibrinogenemia could contribute to PMT and SEA formation.

BACKGROUND Intestinal ischemia has been described in case reports of patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) disease (coronavirus disease 19, COVID-19). AIM To define the clinical and histological, characteristics, as well as the outcome of ischemic gastrointestinal manifestations of SARS-CoV-2 infection. METHODS A structured retrospective collection was promoted among three tertiary referral centres during the first wave of the pandemic in northern Italy. Clinical, radiological, endoscopic and histological data of patients hospitalized for COVID-19 between March 1 st and May 30 th were reviewed. The diagnosis was established by consecutive analysis of all abdominal computed tomography (CT) scans performed. RESULTS Among 2929 patients, 21 (0.7%) showed gastrointestinal ischemic manifestations either as presenting symptom or during hospitalization. Abdominal CT showed bowel distention in 6 patients while signs of colitis/enteritis in 12. Three patients presented thrombosis of main abdominal veins. Endoscopy, when feasible, confirmed the diagnosis (6 patients). Surgical resection was necessary in 4/21 patients. Histological tissue examination showed distinctive features of endothelial inflammation in the small bowel and colon. Median hospital stay was 9 d with a mortality rate of 39%. CONCLUSION Gastrointestinal ischemia represents a rare manifestation of COVID-19. A high index of suspicion should lead to investigate this complication by CT scan, in the attempt to reduce its high mortality rate. Histology shows atypical feature of ischemia with important endotheliitis, probably linked to thrombotic microangiopathies.

Purpose Pulmonary embolism (PE) in COVID-19 patients can play a key role in precipitating clinical conditions. We aimed to evaluate PE distribution on CTA and to investigate any possible association with D-dimer (DD), pulmonary stage of disease and prognosis. Method COVID-19 patients of two affiliated Hospitals, undergone a CTA examination for PE suspicion, were retrospectively enrolled. Comorbidities, laboratory tests and clinical outcomes (hospitalization, discharge, death) were assessed. A parenchymal stage (early, progressive, peak, absorption) for lung involvement was assigned. Results A cohort of 114 patients (mean age 61 years; 26.3% females) with severe COVID-19 pneumonia were evaluated. At last follow-up 25 (21.9%) were hospitalized, 72 (63.2%) discharged, 17 (14.9%) dead. Eighty-eight patients (77.2%) had at least one comorbidity, being cardiovascular ones the most frequent (44.7%). CTA revealed PE in 65 patients (57%), with concomitant pulmonary trunk and/or main arteries involvement in 16.9%. PE defects were ubiquitous in 18.5% of cases. The predominant parenchymal stages were the progressive (24.6%) and peak (67.7%). DD levels showed a significant correlation with PE occurrence and extent in pulmonary branches, despite anticoagulant therapies; trend of correlation with pulmonary stages was also noted. Conclusions PE is a frequent complication in severe COVID-19 patients, particularly during central parenchymal stages and despite ongoing anticoagulant therapy. CTA and DD levels play a crucial role in the assessment of suspected PE, despite anticoagulant therapies, along with proper information about lung involvement extent.

Purpose To report ischemic and haemorrhagic abdominal complications in a series of COVID-19 patients. To correlate these complications with lung involvement, laboratory tests, comorbidities, and anticoagulant treatment. Methods We retrospectively included 30 COVID-19 patients who undergone abdomen CECT for abdominal pain, between March 16 and May 19, 2020. Ischemic and haemorrhagic complications were compared with lung involvement (early, progressive, peak or absorption stage), blood coagulation values, anticoagulant therapy, comorbidities, and presence of pulmonary embolism (PE). Results Ischemic complications were documented in 10 patients (7 receiving anticoagulant therapy, 70%): 6/10 small bowel ischemia (1 concomitant obstruction, 1 perforation) and 4/10 ischemic colitis. Main mesenteric vessels were patent except for 1 superior mesenteric vein thrombosis. Two ischemia cases also presented splenic infarctions. Bleeding complications were found in 20 patients (all receiving anticoagulant treatments), half with active bleeding: hematomas in soft tissues (15) and retroperitoneum (2) and gastro-intestinal bleeding (3). Platelet and lymphocyte were within the normal range. d-Dimer was significantly higher in ischemic cases (p < 0.001). Most of the patients had severe lung disease (45% peak, 29% absorption), two patients PE. Conclusions Ischemic and haemorrhagic abdominal complications may occur in COVID-19 patients, particularly associated to extended lung disease. CT plays a key role in the diagnosis of these potentially life- threatening conditions.