Histopathology . Clinicopathologic Findings in COVID-19-Associated Ischemic Enterocolitis

[tetano]

Histopathology


. 2021 Jul 22.
doi: 10.1111/his.14457. Online ahead of print.
Clinicopathologic Findings in COVID-19-Associated Ischemic Enterocolitis


M Lisa Zhang ^{1 2} , Frank Jacobsen ³ , Brian J Pepe-Mooney ^{2 4 5} , Mari Mino-Kenudson ^{1 2} , Vikram Deshpande ^{1 2} , Angela R Shih ^{1 2} , Anthony R Mattia ^{1 2 6} , Wolfram Goessling ^{2 4 5 7} , John O Hwabejire ^{2 8} , George C Velmahos ^{2 8} , Joseph Misdraji ^{1 2}



Affiliations

• PMID: 34292620
• DOI: 10.1111/his.14457

Abstract

Aims: Coronavirus disease 2019 (COVID-19) has been recognized as a predominantly respiratory tract infection, but some patients manifest severe systemic symptoms/coagulation abnormalities. We evaluated the impact of severe COVID-19 infection on the gastrointestinal tract.
Methods and results: We examined clinicopathologic findings in 28 resected ischemic bowels from 22 patients with severe COVID-19. Most patients required intubation preoperatively and presented with acute decompensation shortly before surgery. D-dimer levels were markedly elevated in all measured cases (mean: 5394 ng/mL). Histologically, 25 cases (19 patients) showed evidence of acute ischemia with necrosis. In this group, the most characteristic finding was the presence of small vessel fibrin thrombi (24/25 cases, 96%), which were numerous in 64% of cases. Compared to a control cohort of 35 non-COVID-19-related acute ischemic bowels, patients with COVID-19 were significantly more likely to show isolated small intestine involvement (32% vs. 6%, p<0.001), small vessel fibrin thrombi (100% vs. 43%, p<0.001), submucosal vessels with fibrinous degeneration and perivascular neutrophils (90% vs. 54%, p<0.001), fibrin strands within submucosal vessels (58% vs. 20%, p=0.007), and histologic evidence of pneumatosis (74% vs. 34%, p=0.010). Three cases in this cohort had histopathologic findings normally seen in the setting of chronic ischemia, notably prominent fibroblastic proliferation affecting the outer layer of the muscularis propria.
Conclusions: Herein, we describe the histopathologic findings in COVID-19-associated ischemic bowel and postulate a relationship to the hypercoagulable state seen in patients with severe COVID-19 infection. Additional experience with these cases may further elucidate specific features or mechanisms of COVID-19-associated ischemic enterocolitis.

Keywords: COVID-19; fibrin thrombi; gastrointestinal; ischemic enterocolitis; microthrombi.