Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0032463 (polycythemia vera)
 3,374 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The pathogenesis of portal hypertension arising in patients with myeloproliferative disorders has been difficult to understand because liver biopsy findings often show minimal changes. It has been suggested that increased splenic blood flow, hepatic infiltration with hematopoietic cells or sinusoidal fibrosis may be important. We have reviewed the autopsy findings and clinical histories of 97 patients with polycythemia vera and 48 patients with agnogenic myeloid metaplasia collected from three institutions and from the Polycythemia Vera Study Group. Cirrhosis was present in seven patients, one of whom had bleeding varices. Esophageal varices were present clinically in 10 patients without cirrhosis (seven polycythemia and three agnogenic myeloid metaplasia). All of these patients had lesions in small or medium-sized portal veins and four had stenosis of the extrahepatic portal vein with histology compatible with organized thrombi. Nodular regenerative hyperplasia occurred in 14.6% and correlated closely with the presence of portal vein lesions. Thirty patients had greater than 500 ml of ascites, seven of these patients also had varices and six of them had hepatic vein thrombosis. Ascites also correlated with hepatic vein disease confined to small intrahepatic branches. No correlation was seen between hepatic hematopoietic infiltration and signs of portal hypertension. We conclude that esophageal varices are common and are almost always associated with portal vein lesions visible by light microscopy. These portal vein lesions, and the secondary effects of nodular regenerative hyperplasia and portal hypertension, are most likely a result of portal vein thrombosis in patients with myeloproliferative disorders.
 ...
PMID:Hepatic vascular disease and portal hypertension in polycythemia vera and agnogenic myeloid metaplasia: a clinicopathological study of 145 patients examined at autopsy. 222 15

Portal hypertension is a clinical syndrome defined as a portal venous pressure that exceeds 10mmHg. Cirrhosis is the most common cause of portal hypertension and thrombosis of the splenoportal axis not associated with liver cirrhosis is the second cause of portal hypertension in the Western world. The primary myeloproliferative disorders are the main cause of portal venous thrombosis and somatic mutation of Janus Kinase 2 gene (JAK2 V617F) can be found in approximately 90% of polycythemia vera, 50% of essential thrombocyrosis and 50% primary myelofibrosis. A a 55-year-old man with JAK2 mutation-associated splenoportal axis hypertension and bleeding complications due to oesophageal varices is reported. A massive upper bleeding episode made an emergent surgery to be done immediatelly at seventh day. The patient was discharged home at fifteenth day after surgery.
 ...
PMID:Massive upper gastrointestinal bleeding due to splenoportal axis thrombosis in a patient with a tested JAK2 mutation: A case report and review literature. 2769 37