Idiopathic portal hypertension (IPH) is a disorder generally classified as a noncirrhotic portal hypertension of unknown etiology, and is clinically characterized by portal hypertension, splenomegaly, and pancytopenia. The principal pathologic changes of IPH are devastation of the intrahepatic terminal portal radicles with considerable portal fibrosis and secondary atrophy of the liver parenchyma that follows portal thrombosis. The incidence varies considerably with the country. In contrast to its high prevalence in India, IPH is comparatively a rare disorder in Western countries. Middle-aged women are more prone to IPH in Japan. IPH usually suggests a benign prognosis, but sometimes is complicated with severe hemorrhage due to ruptured esophageal varices, or massive splenomegaly. It is mainly managed by supportive treatment such as endoscopic, radiological and/or surgical management for esophageal varices and/or splenomegaly. The definite etiology of IPH is still uncertain, but there are several theories on the potential pathogenesis of IPH. These theories include immunological disorders, infections, and genetic variants.
Japanese study groups usually use the term of "IPH", whereas Indian researchers prefer to use the term non-cirrhotic portal fibrosis for the name of this disorder. Groups in Western countries have proposed terms such as nodular regenerative hyperplasia (NRH), hepatoportal sclerosis, or Idiopathic noncirrhotic portal hypertension.
