Portal vein thrombosis is a rare disorder in which a clot forms blocking the main portal vein going into the liver. This can occur due to previous umbilical (belly button) catheter in the newborn period, a clotting disorder, infection or injury. In many cases, the cause of the thrombosis is never determined.
What Are the Symptoms of Portal Vein Thrombosis?
A clot or blockage in the portal vein eventually causes portal hypertension. The body grows new blood vessels (called varices) in an attempt to get around the blockage. These blood vessels connect blood flow from the intestine directly to the general circulation, bypassing the liver. Portal hypertension causes an enlarged spleen, low platelet counts and/or gastrointestinal bleeding. Some children may have elevated ammonia levels in their blood leading to encephalopathy which can cause a variety of symptoms such as sleeplessness, difficulty concentrating or memory issues. Occasionally the family will have been previously informed that their child needs a liver transplant, or a splenectomy (surgical removal of the spleen).
How Is Portal Vein Thrombosis Treated?
Patients with portal vein thrombosis generally will not require a transplant particularly if the liver is otherwise normal. Dr. Riccardo Superina is the leading expert on portal vein thrombosis, and he perfected the meso-rex bypass shunt to correct the condition. He has performed the shunt on more than 200 patients over the past 20 years. The advantage of the Rex shunt over standard therapies, such as repeated banding, splenectomy or other shunts is the meso-rex bypass shunt (“Rex”) shunt restores the normal blood flow to the liver and is essentially curative. Patients with portal vein thrombosis who are referred for possible Rex shunt will undergo a series of pre-op testing to prepare for the surgery. These generally include an abdominal (belly) CT scan and ultrasound, an ultrasound of the neck veins, an echocardiogram (ECHO) to look at the heart, and a venogram and liver biopsy.
The jugular vein in the neck is used to create a bypass shunt around the clotted area of the portal vein. This re-establishes the normal blood flow to the liver. The operation usually lasts about five to six hours, but can sometimes take longer.
On rare occasions, a Rex shunt is not possible. In these instances, an alternative shunt called a distal splenorenal shunt is performed.
The usual hospital stay is about a week which includes a few days in the PICU (Pediatric Intensive Care Unit). After surgery patients are started on Plavix (generic name: clopidogrel), an oral medication that helps prevent clots in the shunt. There are follow up visits every three months for the first year. The visits usually include an ultrasound and lab tests.