The basic pathology is some kind of obstructive pathology in the
portal,
hepatic or
splenic vein that causes obstruction of
venous blood flow from the spleen towards the heart. The cause of such obstruction may be abnormalities present at birth (congenital) of certain veins, blood clots, or various underlying disorders causing
inflammation and obstruction of veins (vascular obstruction) of the liver. ==Diagnosis==