MPL and JAK2 exon 12 mutations in patients with the Budd-Chiari syndrome or extrahepatic portal vein obstruction.

To the editor: The Budd-Chiari syndrome (BCS) and extrahepatic portal vein obstruction (EHPVO) are splanchnic vein thromboses (SVT) that may occur as presenting complications of undiagnosed chronic myeloproliferative disorders (CMPD). Diagnosis of the underlying CMPD may be difficult because