Keywords
abdominal pain - COVID-19 - hypercoagulability - anticoagulation - thrombosis
Introduction
COVID-19 coagulopathy is a hypercoagulable state which predisposes to venous, arterial and small vessel thrombosis.[1] We describe a patient with COVID-19 who developed an acute superior mesenteric vein (SMV) thrombosis with acute intestinal obstruction despite adequate anticoagulation.
Case Description
A 30-year-old man presented to our institution on June 2020 with central abdominal pain and bilious vomiting for 2 days. He was previously diagnosed with COVID-19 and SMV thrombosis on May 2020 at another public hospital. CT of the abdomen and pelvis (CTAP) showed SMV thrombosis ([Fig. 1A]), with bilateral basal pneumonia. Nasopharyngeal swab sent for severe acute respiratory syndrome coronavirus 2 polymerase chain reaction was positive. Prothrombin time (PT) and activated partial thromboplastin time (aPTT) were normal, but lupus anticoagulant was positive with a mildly raised fibrinogen of 4.65 g/L and markedly raised D-dimer of >20.0 μg/mL, consistent with COVID-19 coagulopathy. Twice-daily enoxaparin at 1 mg/kg was initiated and planned for 3 months. He was discharged well after a 17-day hospitalization. On review by our team, he claimed compliance to his anticoagulation. An urgent CTAP ([Fig. 1B]) showed small intestine obstruction. An exploratory laparotomy with resection of the affected small bowel loop was performed, with histology revealing ulceration, transmural congestion, haemorrhage ([Fig. 2A]) and organizing thrombosis in mesenteric veins ([Fig. 2B]). Anti-cardiolipin IgG and IgM as well as anti-B2 glycoprotein, paroxysmal nocturnal haemoglobinuria (PNH) and molecular testing for myeloproliferative neoplasms (MPN) were all negative. Anticoagulation was resumed and the patient was discharged well.
Fig. 1 (A) Superior mesenteric vein (SMV) thrombosis (filling defect seen highlighted by white arrow). (B) Dilated bowel loops extending from the duodenum to the jejunum. Interval improvement in the extent of previously noted SMV thrombosis, with interval reduction in calibre of the SMV and increased opacification. Filling defect seen in the SMV (highlighted by white arrow).
Fig. 2 (A) Histology of small bowel showing ulceration (black arrows), transmural congestion and haemorrhage (haematoxylin and eosin [H&E] ×20). (B) Histology showing an organizing thrombus in a mesenteric vein (left vessel, black arrow) (H&E ×40). A small mesenteric artery is seen on the right.
Conclusion
This is a rare presentation of COVID-19-associated SMV thrombosis resulting in ischaemic bowel, with a lupus anticoagulant being frequently detected in COVID-19 patients as well.[2] Clinicians encountering splanchnic vein thrombosis should be aware that this is an unusual site of thrombosis.[3] In patients without obvious causes like liver cirrhosis, pancreatitis, advanced malignancy, abdominal infection and post–abdominal surgery, the exclusion of MPN, PNH, antiphospholipid syndrome and COVID-19 should be strongly considered. Given the increased incidence of COVID-19-associated thromboembolic events[4] and the associated morbidity and mortality,[5] thromboprophylaxis should be strongly considered in hospitalized COVID-19 patients.
