Published online Sep 26, 2020. doi: 10.12998/wjcc.v8.i18.4193
Peer-review started: May 4, 2020
First decision: May 21, 2020
Revised: May 26, 2020
Accepted: August 25, 2020
Article in press: August 25, 2020
Published online: September 26, 2020
Among the various types and causes of mesenteric ischemia, superior mesenteric vein (SMV) thrombosis is a rare and ambiguous disease. If a patient presents with SMV thrombosis, past medical history should be reviewed, and the patient should be screened for underlying disease. SMV thrombosis may also occur due to systemic infection. In this report, we describe a case of SMV thrombosis complicated by influenza B infection.
A 64-year-old male visited the hospital with general weakness, muscle aches, fever, and abdominal pain. The patient underwent computed tomography (CT) and was diagnosed with SMV thrombosis. Since the patient’s muscle pain and fever could not be explained by the SMV thrombosis, the clinician performed a test for influenza, which produced a positive result for influenza B. The patient had a thrombus in the SMV only, with no invasion of the portal or splenic veins, and was clinically stable. Anticoagulation treatment was prescribed without surgery or other procedures. The follow-up CT scan showed improvement, and the patient was subsequently discharged with continued oral anticoagulant treatment.
This case provides evidence that influenza may be a possible risk factor for SMV thrombosis. If unexplained abdominal pain is accompanied by an influenza infection, examination of an abdominal CT scan may be necessary to screen for possible SMV thrombosis.
Core Tip: Superior mesenteric vein (SMV) thrombosis, a potentially fatal type of mesenteric ischemia, usually occurs in individuals with predisposed factors that should be investigated upon diagnosis. Identification of a predisposed factor is crucial in SMV thrombosis because recurrence may be prevented by treatment of the underlying condition. Rarely, an influenza infection can complicate SMV thrombosis, and this report presents the third known case of this occurrence. The evidence presented in this report indicates that SMV thrombosis possibly induced by an influenza virus should be considered when an influenza patient presents with unexplained abdominal pain, or conversely, when an SMV thrombosis patient presents with a high fever of unknown cause. Moreover, the potential treatments for SMV thrombosis including medical interventions, transvenous catheter-based interventions, or surgery may differ according to the degree of vascular involvement and symptoms. These differences are highlighted in this report when the current case is compared to the two previously reported cases.