Role of theJAK2 mutation in the diagnosis of chronic myeloproliferative disorders in splanchnic vein thrombosis

High prevalence of the JAK2 V617F mutation in patients with extrahepatic portal vein thrombosis

“…[1][2][3][4] Recently the acquired JAK2 V617F mutation has been recognized as closely related with CMD, providing a robust diagnostic tool. 5 We read with interest the article by Primignani et al, 6 who found the JAK2 mutation in 40% of 20 HVT patients and 36% of 73 PVT patients.…”

Prodromal myeloproliferative neoplasms: The 2008 WHO classification

“…One may speculate that in a significant number of these patients characteristic complications have already occurred during the prodromal stages, preceding the readily recognizable overt polycythemic manifestations. In this context, the question arises how many of the JAK2V617F-positive patients with splanchnic vein thrombosis, Budd Chiari syndrome or cerebral thrombosis may actually present early stage or smouldering PV according to their BM morphology, especially when associated with Epo levels below the normal range [34][35][36][37][38][39]41]. Moreover, it was found that increase in JAK2V617F allele burden during follow-up indicates overt PV transformation in cases which initially mimicked ET and presented without significant erythrocytosis [75,76].…”

“…These complications were especially observed, when following the diagnostic criteria of the Polycythemia vera Study Group (PVSG) [5,7,21]. In this context, a number of recent reports have described patients without clinical presentation of overt MPN but a positive JAK2V617F mutation status associated with cerebral or splanchnic vein thrombosis including Budd Chiari syndrome [34][35][36][37][38][39][40][41]. Unfortunately, detailed descriptions of BM findings are mostly lacking in these cases, and therefore, it can only be speculated that a considerable number of these occult MPN represent prodromal stages of the major MPN categories (PV, ET, initial-early stage PMF).…”

Mesenteric Venous Thrombosis

“…Testing for JAK2 mutation has replaced bone marrow biopsy as the initial screening method for diagnosis of myeloproliferative neoplasms. 25 Hyperhomocysteinemia, Protein C or S deficiency, prothrombin gene mutation, and antithrombin III deficiency are other disorders to consider.…”