What is Portal Vein Thrombosis?
Portal Vein Thrombosis is a pathological condition concerning the liver in which the portal vein which carries blood from the intestines to the liver gets blocked or thrombosed as a result of a clot. In many cases of Portal Vein Thrombosis, there are no symptoms but as the condition advances enlargement of the spleen may occur or there may be severe bleeding from the esophagus. People with liver cirrhosis tend to get this condition more than other people and if they do get Portal Vein Thrombosis then the scarring in the liver deteriorates.
The most preferred and best way to diagnose Portal Vein Thrombosis is by doing a Doppler Ultrasound which will clearly show reduced blood flow to the liver from the portal vein. Treatment of Portal Vein Thrombosis is done by treating the underlying cause. Medications may be given to dissolve the clot and restore normal blood flow. In some cases angiography may be done so that blood can go to the liver through an alternate route. Blood thinners may be given to prevent future clots from occuring and causing Portal Vein Thrombosis.
As a result of Portal Vein Thrombosis, the pressure within the portal vein increases resulting in development of a condition called portal hypertension which causes the spleen to get enlarged. Varicose veins may also develop in the esophagus and in the stomach called esophageal varices and gastric varices respectively as a result of this increased pressure in the portal veins. These varices can bleed profusely and there may be significant loss of blood due to these.
Portal Vein Thrombosis can also cause fluid buildup in the abdomen as a result of backflow of blood from the liver due to the clot. This is seen mostly in people who have a prior history of liver damage or have a history of liver cirrhosis. It can also be caused as a result of intravenous fluids given due to severe bleeding as a result of esophageal and gastric varices. The condition of people with liver cirrhosis deteriorates if they develop Portal Vein Thrombosis.
What Causes Portal Vein Thrombosis?
Portal Vein Thrombosis is caused due to slow movement of blood from the portal vein usually due to clot formation. This is seen mostly in people with liver cirrhosis as the liver in these people is damaged to such an extent that the flow of blood from the portal vein to the liver is extremely slow causing Portal Vein Thrombosis.
Thus, any medical condition that tends to cause the blood to move slowly through the portal vein can cause Portal Vein Thrombosis. Depending on the age, the different causes of Portal Vein Thrombosis are:
- Neonates. Infection of the umbilical cord stump
- Children. Appendicitis which spreads to the portal veins
- Adults. Medical conditions like polycythemia, cancer of the liver, pancreas, kidney, or adrenal gland, liver cirrhosis, an injury to the liver and surrounding structures, conditions which may increase incidences of clotting, and pregnancy tend to cause Portal Vein Thrombosis
What are the Symptoms of Portal Vein Thrombosis?
Portal Vein Thrombosis is a relatively asymptomatic medical condition which gradually develops and once it advances to cause related disorders like esophageal or gastric varices which may bleed profusely then the affected individual may experience hemoptysis. Person suffering from portal vein thrombosis may have symptoms of black tarry stools suggestive of blood passing through the digestive tract.
How is Portal Vein Thrombosis Diagnosed?
Portal Vein Thrombosis is suspected in an individual if he or she has an enlarged spleen, has bleeding gastric or esophageal varices, or conditions that are typical of a Portal Vein Thrombosis like umbilical cord infection in neonates or appendicitis in children.
Liver function tests may be done to diagnose Portal Vein Thrombosis but the results are not very much convincing for a definitive diagnosis to be made.
The best and the most preferred study to diagnose Portal Vein Thrombosis is Doppler Ultrasonography. This study clearly shows the reduced blood flow through the portal vein thus confirming the diagnosis of Portal Vein Thrombosis.
How is Portal Vein Thrombosis Treated?
If there is a sudden formation of a clot causing Portal Vein Thrombosis then medication to dissolve the clot is given so that normal blood flow is restored, although the effectiveness of this treatment is not exactly clear. In cases where a clot develops over a period of time then blood thinners like heparin is given to the patient to prevent further clot formation. In cases of Portal Vein Thrombosis in neonates and children, the underlying cause of Portal Vein Thrombosis is treated to restore normal blood flow to the liver.
The complications arising from Portal Vein Thrombosis like gastric and esophageal varices are the most challenging to treat. The bleeding can be stopped utilizing various techniques. The most preferred technique is inserting rubber bands through an endoscope into the esophagus and tying off the varicose veins. Apart from this, antihypertensives can be given to restore normal pressure in the portal veins and thus prevent bleeding from varicose veins. Octreotide is a medication that is at times also given to reduce blood flow to the liver and decrease pressure on the abdomen caused due to Portal Vein Thrombosis.