Non-cirrhotic portal hypertension – Concept, diagnosis and clinical management

Summary

Non-cirrhotic portal hypertension (NCPH) is mainly related to vascular disorders in the portal system, granuloma formation with periportal fibrosis or genetic alterations affecting the hepatobiliary system. For the diagnosis of the so-called idiopathic NCPH, it is essential to rule out chronic liver diseases associated with progression to cirrhosis as viral hepatitis B and C, alcoholic and non-alcoholic fatty liver, autoimmune disease, hereditary hemochromatosis, Wilson's disease as well as primary biliary cirrhosis and primary sclerosing cholagitis. This mini review will focus on the most common types of NCPH, excluding the idiopathic NCPH. Primary Budd-Chiari syndrome, characterized by obstruction of hepatic venous outflow, must be distinguished from sinusoidal obstruction syndrome, a cause of portal hypertension associated with exposure to toxic plants or therapeutic agents. Noninvasive imaging methods usually help the diagnosis of both Budd-Chiari syndrome and portal thrombosis, the later a relatively frequent cause NCPH. Clinical presentation and management of these vascular disorders are evaluated. Schistosomiasis, a worldwide spread endemic parasitic disease, may evolve to severe forms of the disease with huge spleen and gastroesophageal varices due to presinusoidal portal hypertension. Although management of acute upper gastrointestinal bleeding is similar to that of cirrhosis, prevention of rebleeding differs. Instead of portosystemic shunt procedures, the esophagogastric devascularization with splenectomy is the accepted surgical alternative. Its association with endoscopic therapy is suggested to be the best option for PH due to schistosomiasis. In conclusion, the prompt diagnosis of the disorder leading to non-cirrhotic portal hypertension is essential for its correct management.

Introduction

Portal hypertension (PH) is a complex syndrome, consequence of hemodynamic abnormalities of the portal vein system, linked to increased hepatic resistance and altered portal blood inflow. The hemodynamic changes occurring in both the splanchnic and systemic circulation give rise to the main complications of chronic liver disease. Upper gastrointestinal bleeding (UGIB), ascites, portosystemic encephalopathy, hepatorenal syndrome, and hepatopulmonary syndrome are the main clinical presentations of PH. All of them are essentially related to the formation of collaterals and hyperdynamic circulation at the splanchnic and systemic levels. Some of these clinical complications are most common and evident in cirrhotic portal hypertension, but all may occur in any non-cirrhotic clinical condition that presents with hypertension of the portal vein system, either in the presinusoidal, sinusoidal or post-sinusoidal area [1].

Non-cirrhotic portal hypertension (NCPH) may be due to vascular disorders, such as thrombosis, membrane formation, or fistulas. Early recognition of these conditions is essential to enable implementation of therapeutic measures, in an attempt to reverse the natural course of the disease or prophylactic strategies to prevent disease progression. The two most common types of vascular disorders leading to PH, portal vein thrombosis and primary Budd-Chiari syndrome, deserve special attention. It is also important to evaluate the diagnosis and adequate management of other types of NCPH related to schistosomiasis, sarcoidosis or congenital hepatic fibrosis. The idiopathic NCPH, which was first described in India [2], is characterized by the increase of venous pressure gradient in the absence of known cause of liver disease or vein thrombosis and is rare in Western patients. For its diagnosis it is essential to rule out chronic liver diseases associated with progression to cirrhosis as viral hepatitis B and C, alcoholic and non-alcoholic fatty liver, autoimmune disease, hereditary hemochromatosis, Wilson's disease as well as primary biliary cirrhosis and primary sclerosing cholangitis. This mini review will focus on the most common types of NCPH, excluding the idiopathic NCPH that has been extensively evaluated recently [3], [4].