Portal hypertension is clinically characterized by a portal venous pressure gradient between the inferior vena cava and the portal vein is more than 5 mm. Liver cirrhosis remains the leading cause of portal hypertension in the western world. However, there are conditions where portal hypertension can even occur without liver cirrhosis, referred to as Noncirrhotic portal hypertension (NCPH). The term NCPH has been derived from a variety of histopathological entities such as hepatoportal sclerosis, noncirrhotic portal fibrosis, nodular regenerative hyperplasia, or incomplete septal fibrosis. In the absence of other causes of cirrhosis and portal venous thrombosis, the condition is termed idiopathic noncirrhotic portal hypertension. The histopathological findings of INCPH are not entirely specific to portal hypertension, similar changes can be seen in patients without portal hypertension. Therefore the term Porto-sinusoidal vascular disorder(PSVD) has been recently introduced to define a group of liver vessel disorders affecting the portal venules and sinusoids irrespective of the absence or presence of liver cirrhosis. This disease entity can have a varied clinical presentation and histological findings and has been associated with several immunological and systemic disorders.
Porto-sinusoidal vascular disease - Currently, for clinical practice, the VALDIG group has given a working definition for PSVD.
"Liver biopsy ≥20mm without cirrhosis with either 1 specific sign of portal hypertension OR 1 specific histological finding for PSVD" OR "Liver biopsy ≥20mm without cirrhosis with 1 sign not specific for portal hypertension AND 1 sign not specific for PSVD"