Gentiana Voinescu M.D.              Univ. of Missouri--Columbia
Prothrombin 20210A gene mutation: a common abnormality causing an unusual abdominal 
  venous thrombosis   
         
 

A mutation in the prothrombin gene (GV A20210) has been associated with higher plasma prothrombin levels and an increased tendency for venous thrombosis. We present a 39-year-old healthy white female who was seen in a local emergency room seven days prior to admission to our hospital, complaining of gradual onset of midepigastric pain, mild nausea and low grade fever. At the 2-day follow up with her primary care physician, an ultrasound of the abdomen was diagnostic for extensive thrombosis of the portal and superior mesenteric vein. She was transferred to our facility after laboratory tests were drawn to assess her for hypercoagulable states. These included: protein C, protein S, anticardiolipin antibodies, activated protein C resistance and lupus anticoagulant.

On admission the patient denied abdominal trauma, previous clotting problems in her or her family, smoking, birth control pills usage, weight loss or previous pancreatic problems. The patient was on no medications. Physical examination revealed moderate epigastric tenderness, no rebound or guarding. The patient was started on intravenous heparin. A work-up for myeloproliferative disorders, tumors, and pancreatitis was negative. Findings included a normal complete blood count, amylase, lipase, chest X-ray, and mammogram. Computerized tomography of the abdomen showed occlusion of the superior mesenteric vein and portal vein. Since the hypercoagulable profile was negative to date, a polymerase chain reaction assay for prothrombin 20210A gene mutation was obtained. This revealed that the patient was heterozygous for the mutation. She began coumadin therapy. The computerized tomography of the abdomen repeated after six weeks of anticoagulation demonstrated interval reconstitution of blood flow through the portal vein and improvement in size of superior mesenteric vein thrombosis.

Keywords: thrombosis, prothrombin 20210A gene mutation, risk factors.