Evaluation of abdominal computed tomography findings in patients with COVID-19: a multicenter study

Abstract

Purpose: To evaluate the frequency of abdominal computed tomography (CT) findings in patients with coronavirus disease-2019 (COVID-19) and interrogate the relationship between abdominal CT findings and patient demographic features, clinical findings, and laboratory test results as well as the CT atherosclerosis score in the abdominal aorta.

Methods: This study was designed as a multicenter retrospective study. The abdominal CT findings of 1.181 patients with positive abdominal symptoms from 26 tertiary medical centers with a positive polymerase chain-reaction test for severe acute respiratory syndrome coronavirus 2 were reviewed. The frequency of ischemic and non-ischemic CT findings as well as the association between CT findings, clinical features, and abdominal aortic calcific atherosclerosis score (AA-CAS) were recorded.

Results: Ischemic and non-ischemic abdominal CT findings were detected in 240 (20.3%) and 328 (27.7%) patients, respectively. In 147 patients (12.4%), intra-abdominal malignancy was present. The most frequent ischemic abdominal CT findings were bowel wall thickening (n = 120; 10.2%) and perivascular infiltration (n = 40; 3.4%). As for non-ischemic findings, colitis (n = 91; 7.7%) and small bowel inflammation (n = 73; 6.2%) constituted the most frequent disease processes. The duration of hospital stay was found to be higher in patients with abdominal CT findings than in patients without any positive findings (13.8 ± 13 vs. 10.4 ± 12.8 days, P < 0.001). The frequency of abdominal CT findings was significantly higher in patients who did not survive the infection than in patients who were discharged after recovery (41.7% vs. 27.4%, P < 0.001). Increased AA-CAS was found to be associated with a higher risk of ischemic conditions in abdominal CT examinations.

Conclusion: Abdominal symptoms in patients with COVID-19 are usually associated with positive CT findings. The presence of ischemic findings on CT correlates with poor COVID-19 outcomes. A high AA-CAS is associated with abdominal ischemic findings in patients with COVID-19.

Keywords: COVID-19; abdomen; abdominal aorta; arteriosclerosis; computed tomography.

Figure 1

Flowchart of patient selection for the study cohorts. CT, computed tomography; COVID-19, coronavirus disease-2019; PCR, polymerase chain-reaction.

Figure 2

Abdominal aorta calcification score measurement method in the abdominal aorta.

Figure 3

Axial unenhanced computed tomography image demonstrating a diffusely swollen pancreas and peripancreatic fat inflammation (arrows) consistent with edematous pancreatitis in a 65-year-old male patient with coronavirus disease-2019 who presented with abdominal pain.

Figure 4

A 39-year-old woman with coronavirus disease-2019 presented with abdominal pain. Axial (a) and coronal (b) computed tomography images demonstrating the thickening of the ascending colon wall (arrows).

Figure 5

Axial (a) and coronal (b) contrast-enhanced computed tomography images of a 70-year-old female patient with coronavirus disease-2019 revealing perivascular infiltration, mesenteric stranding (arrows), and bowel dilatation, which indicates bowel ischemia. The patient underwent segmental bowel resection surgery because of the progressive deterioration in her clinical status.

Figure 6

Acute superior mesenteric vein thrombosis. A 74-year-old woman with acute myeloid leukemia who presented with shortness of breath, abdominal pain, and diarrhea was diagnosed with coronavirus disease-2019. Axial contrast-enhanced abdominal computed tomography (CT) images (a, b) obtained 1 month before hospital admission reveal patent abdominal aorta and right portal vein. Axial arterial phase contrast-enhanced CT image obtained on hospital admission (c) demonstrating an acute thrombus in the abdominal aorta (arrow). Axial portal venous phase contrast-enhanced CT image (d) reveals an acute thrombus in the right portal vein (arrow). Axial chest CT image (e) demonstrating bilateral ground-glass opacities in both lungs. Coronal-reformatted abdominal CT image (f) showing an acute thrombus in the superior mesenteric vein (arrow). Note the bowel wall thickening of the ascending colon (arrowhead) and ascites.

Figure 7

Renal infarct. (a) Axial chest computed tomography (CT) image showing bilateral ground-glass density and consolidations (arrows) in the peripheral portions of the lungs. Axial (b) and coronal (c) CT images reveal focal unenhanced areas (arrowheads) in the renal parenchyma, representing renal infarcts.

Figure 8

Acute superior mesenteric artery embolism. Sagittal (a), oblique reformatted (b), and axial (c) computed tomography (CT) images of a 61-year-old woman with sudden onset abdominal pain 6 days after the diagnosis of coronavirus disease-2019, revealing a hypodense filling defect (arrows) in the superior mesenteric artery lumen. Axial CT image (d) of the same patient at the pelvic level revealing hypo-enhancing segments of the ileum wall (arrows) and free intra-abdominal gas (arrowheads) behind the uterus (u), suggesting bowel wall ischemia and resultant perforation.