Clinicopathological findings in patients with COVID-19-associated ischaemic enterocolitis.

AIMS: Coronavirus disease 2019 (COVID-19) has been recognised as a predominantly respiratory tract infection, but some patients manifest severe systemic symptoms/coagulation abnormalities. The aim of this study was to evaluate the impact of severe COVID-19 infection on the gastrointestinal tract. METHODS AND RESULTS: We examined clinicopathological findings in 28 resected ischaemic 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 ischaemia with necrosis. In this group, the most characteristic finding was the presence of small vessel fibrin thrombi (24 of 25 cases, 96%), which were numerous in 64% of cases. Patients with COVID-19 were significantly more likely than a control cohort of 35 non-COVID-19-associated acute ischaemic bowels to show isolated small intestine involvement (32% versus 6%, P < 0.001), small vessel fibrin thrombi (100% versus 43%, P < 0.001), submucosal vessels with fibrinous degeneration and perivascular neutrophils (90% versus 54%, P < 0.001), fibrin strands within submucosal vessels (58% versus 20%, P = 0.007), and histological evidence of pneumatosis (74% versus 34%, P = 0.010). Three cases in this cohort had histopathological findings normally seen in the setting of chronic ischaemia, notably prominent fibroblastic proliferation affecting the outer layer of the muscularis propria. CONCLUSIONS: Herein, we describe the histopathological findings in COVID-19-associated ischaemic bowels and postulate a relationship with 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 ischaemic enterocolitis.

Learning During and From a Crisis: The Student-Led Development of a COVID-19 Curriculum.

PROBLEM: The speed and scope of the upheaval that COVID-19 inflicted on medical education made innovation a necessity. While medical students wanted high-quality, consolidated educational resources on COVID-19, the medical school faculty who typically produced such resources were increasingly burdened with clinical, administrative, and personal commitments. However, students eager to contribute to the pandemic response were well suited to create these instructional materials for their peers. APPROACH: In mid-March 2020, a group of students at Harvard Medical School came together to synthesize the key facts and collate the best existing educational materials about the COVID-19 pandemic into a unified learning resource. The materials were faculty reviewed and shared freely online. The curriculum now contains 8 modules that are updated regularly. Throughout this process, the student authors prioritized accessibility, iterative improvement, and effective pedagogy. OUTCOMES: To date, nearly 80,000 users from 132 countries have accessed the curriculum. It has been referenced or incorporated into courses at Harvard Medical School and more than 30 other medical schools across the country. About 40% of all users are from outside the United States, and the materials have been translated into 28 languages. This effort has spurred a number of other educational initiatives led by medical student groups in the United States and abroad. NEXT STEPS: As understanding of the COVID-19 pandemic is constantly changing, the student authors' immediate goal is to keep the curriculum up to date in the months to come. They plan to maintain existing partnerships with medical schools and student groups around the world while pursuing new opportunities to expand the curriculum's reach, provide education, and build community. Students and educators alike should leverage student-driven education efforts to benefit other learners both within and, importantly, beyond their institutions.