Thrombotic Features as the Primary Cause of SARS-CoV-2 Related Acute Abdomen in Children

Objectives: We performed a retrospective case control study to evaluate the histological characteristics of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) positive pediatric patients undergoing laparoscopic exploration for acute abdomen symptoms. To our knowledge this is the first study that analyzes histopathological characteristics of abdominal tissues in SARS-CoV-2 children. Study design: We enrolled 8 multisystem inflammatory syndrome in children (MIS-C) patients and 4 SARS-CoV-2 positive patients who underwent intestinal resection versus 36 control appendectomies from 2 pediatric tertiary referral centers between March 2020 and July 2021. Surgical resection samples were evaluated on several histological sections focusing on general inflammatory pattern and degree of inflammation. Peculiar histological features (endotheliitis and vascular thrombosis) were semi-quantitatively scored respectively in capillary, veins, and arteries. Results: All SARS-CoV-2 related surgical samples showed thrombotic patterns. Those patterns were significantly less frequent in SARS-CoV-2 negative appendectomies (P = 0.004). The semi-quantitative score of thrombosis was significantly higher (P = 0.002) in patients with SARS-CoV-2 related procedures. Conclusions: Our results showed that SARS-CoV-2 can cause thrombotic damage in abdominal tissues both in the acute phase of the infection (SARS-CoV-2 related appendectomies) and secondary to cytokine storm (MIS-C).