title: Splanchnic venous thrombosis driven by a constitutively activated JAK2 V617F philadelphia-negative myeloproliferative neoplasm: a case report.
abstract: BACKGROUND
  Splanchnic venous thrombosis (SVT) has varied etiology with Philadelphia-negative myeloproliferative neoplasms (MPNs) being the most frequent underlying prothrombotic factor. Hematological indices often remain within normal range because of portal hypertension and its sequelae, causing diagnostic challenges. The high frequency of JAK2 mutation among patients with SVT reinforces the diagnostic utility of JAK2V617F testing.
  
  
  METHODS
  We report a case of a 62-year-old black man with progressive abdominal swelling and features of decompensated chronic liver disease found to have SVT-portal vein thrombosis and how JAK2 V617F was useful in unmasking an underlying myeloproliferative neoplasm.
  
  
  CONCLUSIONS
  A high index of suspicion for an underlying prothrombotic factor is critical for patients presenting with thrombosis in unusual sites. This is useful in prognostic stratification and patient outcomes. JAK2 mutation screening is now part of the standard diagnostic workup in SVT.
authors.affiliation: Department of Medicine, Makerere University College of Health Sciences, Mulago Hospital, Kampala, Uganda.
authors.forename: Musa
authors.initials: M
authors.lastname: Waiswa
authors.affiliation: Department of Medicine, Makerere University College of Health Sciences, Mulago Hospital, Kampala, Uganda.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Seremba
authors.affiliation: Department of Medicine, Makerere University College of Health Sciences, Mulago Hospital, Kampala, Uganda.
authors.forename: Ponsiana
authors.initials: P
authors.lastname: Ocama
authors.affiliation: Department of Medicine, Makerere University College of Health Sciences, Mulago Hospital, Kampala, Uganda.
authors.forename: Henry
authors.initials: H
authors.lastname: Ddungu
authors.affiliation: Department of Medicine, Makerere University College of Health Sciences, Mulago Hospital, Kampala, Uganda.
authors.forename: Keneth
authors.initials: K
authors.lastname: Opio
authors.affiliation: Department of Medicine, Makerere University College of Health Sciences, Mulago Hospital, Kampala, Uganda.
authors.forename: Clement
authors.initials: C
authors.lastname: Okello
authors.affiliation: Department of Medicine, McMaster University, Hamilton Ontario, Canada.
authors.forename: Timothy
authors.initials: T
authors.lastname: O'shea
authors.affiliation: Department of Medicine, McMaster University, Hamilton Ontario, Canada.
authors.forename: Madeleine
authors.initials: M
authors.lastname: Verhovsek
authors.affiliation: Brigham and Women's Hospital Boston.
authors.forename: Richard
authors.initials: R
authors.lastname: Mutyabule
mesh_terms: D017809:Fatal Outcome; D019337:Hematologic Neoplasms / Q000097:blood / Q000235:genetics*; D006801:Humans; D053614:Janus Kinase 2 / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D009154:Mutation / Q000235:genetics*; D009196:Myeloproliferative Disorders / Q000150:complications / Q000235:genetics; D010677:Philadelphia Chromosome; D011169:Portal Vein / Q000000981:diagnostic imaging; D013152:Splanchnic Circulation; D018608:Ultrasonography, Doppler; D020246:Venous Thrombosis / Q000097:blood / Q000209:etiology / Q000235:genetics*
chemical_list: C507924:JAK2 protein, human; D053614:Janus Kinase 2
keywords: myeloproliferative neoplasm; venous thrombosis
references.citation: Trop Gastroenterol. 2011 Oct-Dec;32(4):279-84
references.pmid: 22696908
references.citation: J Clin Oncol. 2011 Feb 20;29(6):761-70
references.pmid: 21205761
references.citation: Mediterr J Hematol Infect Dis. 2011;3(1):e2011063
references.pmid: 22220260
references.citation: Semin Thromb Hemost. 1997;23(5):411-8
references.pmid: 9387199
references.citation: J Thromb Haemost. 2011 Nov;9(11):2208-14
references.pmid: 22040061
references.citation: Radiology. 2000 Jul;216(1):86-92
references.pmid: 10887231
references.citation: J Hepatol. 2010 Oct;53(4):762-8
references.pmid: 20638742
references.citation: Thromb Res. 2012 Oct;130 Suppl 1:S1-3
references.pmid: 23026649
references.citation: Arch Surg. 1993 Mar;128(3):341-5
references.pmid: 8442693
references.citation: Gastroenterology. 2001 Feb;120(2):490-7
references.pmid: 11159889
references.citation: Lancet. 2005 Mar 19-25;365(9464):1054-61
references.pmid: 15781101
references.citation: Blood. 2012 Dec 13;120(25):4921-8
references.pmid: 23043069
references.citation: Am J Gastroenterol. 2007 Nov;102(11):2464-70
references.pmid: 17958760
references.citation: Blood. 2013 Sep 26;122(13):2176-84
references.pmid: 23823316
references.citation: AJR Am J Roentgenol. 1985 Apr;144(4):749-52
references.pmid: 3883708
references.citation: Ann Intern Med. 1985 Sep;103(3):329-34
references.pmid: 4026081
references.citation: N Engl J Med. 2006 Dec 7;355(23):2452-66
references.pmid: 17151367