Mesenteric ischemia in patients with COVID-19: an updated systematic review of abdominal CT findings in 75 patients.

BACKGROUND: Acute mesenteric ischemia (AMI) is a less common but devastating complication of COVID-19 disease. The aim of this systematic review was to assess the most common CT imaging features of AMI in COVID-19 and also provide an updated review of the literature on symptoms, treatment, histopathological and operative findings, and follow-up of these patients. METHODS: A systematic literature search of four databases: Pubmed, EMBASE, WHO database, and Google Scholar, was performed to identify all the articles which described abdominal CT imaging findings of AMI in COVID-19. RESULTS: A total of 47 studies comprising 75 patients were included in the final review. Small bowel ischemia (46.67%) was the most prevalent abdominal CT finding, followed by ischemic colitis (37.3%). Non-occlusive mesenteric ischemia (NOMI; 67.9%) indicating microvascular involvement was the most common pattern of bowel involvement. Bowel wall thickening/edema (50.9%) was more common than bowel hypoperfusion (20.7%). While ileum and colon both were equally involved bowel segments (32.07% each), SMA (24.9%), SMV (14.3%), and the spleen (12.5%) were the most commonly involved artery, vein, and solid organ, respectively. 50% of the patients receiving conservative/medical management died, highlighting high mortality without surgery. Findings on laparotomy and histopathology corroborated strikingly with CT imaging findings. CONCLUSION: In COVID-19 patients with AMI, small bowel ischemia is the most prevalent imaging diagnosis and NOMI is the most common pattern of bowel involvement. Contrast-enhanced CT is a powerful decision-making tool for prompt diagnosis of AMI in COVID-19, thereby potentially improving time to treat as well as clinical outcomes.

Intestinal ischemic manifestations of SARS-CoV-2: Results from the ABDOCOVID multicentre study.

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 1st and May 30th 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.