Splenic vein thrombosis (SVT) is thrombotic occlusion of the splenic vein. This is usually secondary to pancreatitis, which induces endothelial damage in the splenic vein, eventually leading to thrombosis. Although pancreatitis precedes most cases of SVT, other gastrointestinal pathologies are contributory.
Splenic vein thrombosis (SVT) is a condition that is largely precipitated by both the acute and chronic forms of pancreatitis  . Pancreatitis is responsible for about 60% of cases of SVT, although the latter does not usually transpire during an acute attack, but rather after repeated insult. Patients with a history of pancreatitis have up to a 20% risk of developing SVT . There are other conditions that contribute to the development of SVT to a lesser extent, and these include pancreatic pseudocysts, malignancies, peptic ulcer disease, liver cirrhosis, Mallory-Weiss tears and pancreatic surgery  . Pancreatitis can precipitate SVT because of the close association of the tail of the pancreas with the splenic vein. Any inflammation that occurs in the pancreas inflicts damage on the splenic vein wall, leaving it susceptible to thrombus formation . The splenic wall may also be compressed and thus partially occluded by adjacent enlarged lymph nodes.
SVT leads to sinistral portal hypertension, which in turn leads to gastric and esophageal varices. Many individuals with SVT present with gastrointestinal bleeding from varices, which can be life threatening. Nevertheless, most patients with SVT are asymptomatic. SVT should be considered in patients who present with splenomegaly, but no signs of hepatic, hematologic or portal pathology.
The pathophysiology of SVT, sometimes referred to as pancreatitis-induced SVT when it is secondary to pancreatitis, as well as subsequent GI bleeding, is not understood clearly.
There are several diagnostic modalities for splenic vein thrombosis available to clinicians. These include:
Non-invasive techniques: These are increasingly instrumental in the diagnosis of SVT and pancreatitis, as their efficacy has improved.
A dated diagnostic technique was post mortem analysis.
Patients should be evaluated for GI bleeding, specifically esophageal and gastric varices. The isolated presence of gastric varices, in the absence of esophageal counterparts, is highly suggestive of SVT. About half of individuals with splenic vein thrombosis present with splenomegaly. This is helpful in diagnosis, but its absence does not rule out the possibility of SVT . Given the ambivalence of signs and symptoms in SVT, its diagnosis relies heavily on medical imaging.