Portal Hypertension

There is no specific symptom associated with portal hypertension. The chances of developing this disease increase with diseases of the liver such as cirrhosis. The complications or symptoms associated with portal hypertension are:

• Gastrointestinal bleeding: If the stool has blood or appears tarry, it is a symptom of gastrointestinal bleeding. Sometimes blood in the vomit is caused due to spontaneous rupture of the varices and hence must not be neglected. 
• Ascites: In this condition, there is an accumulation of the fluid in abdomen. 
• Encephalopathy: Poor liver function can also cause confusion and forgetfulness.
• Altered blood counts: Decline in the number of platelets and white blood cells (WBCs) are common in patients with portal hypertension [6].

• Complete blood count: Though this is not a specific test to ascertain diagnosis of the disease, it is still advised. In patients with portal hypertension, levels of platelets and WBCs fall.
• Liver function tests: Determining the levels of aspartate aminotransferase [AST], alanine aminotransferase [ALT], and bilirubin determines the functioning of the liver. 
• Coagulation studies: Tests related to coagulation of blood can also prove beneficial in diagnosing the portal hypertension. Some of such tests are: prothrombin time [PT], international normalized ratio [INR] and partial thromboplastin time [PTT]. 
• Some of the other important tests are: Blood urea nitrogen level, levels of creatinine and electrolytes, pH, arterial blood gas, iron indices, hepatic and hepatitis serologies, albumin and antinuclear antibody levels.
• Imagining studies: Such studies include Duplex Doppler ultrasonography, magnetic resonance imaging, bleeding scan and CT scan. 

Treatment of portal hypertension is focused on the prevention and management of the complications associated with the disease, especially bleeding. The severity of the disease is dependent on the extent of liver function. Modification in diet, medications, surgery and endoscopic procedure can help combat the complications of portal hypertension.

1. Endoscopic therapy: This procedure is the first line of treatment for variceal bleeding. Gastroenterologist can also use rubber bands to stop the bleeding by a procedure called banding. In cases where banding cannot be done, sclerotherapy is the option. In this procedure, a blood-clotting solution is injected to stop bleeding.
2. Medications: Beta-blockers such as nadolol and propranolol may be prescribed which reduce the pressure in the varices, reducing the risk of bleeding. Mental changes that accompany encephalopathy can be managed with lactulose.
3. Transjugular intrahepatic portosystemic shunt (TIPS): In this method, a stent is placed in the middle of the liver rerouting the blood flow to the liver.
4. Devascularization: This is a surgical procedure to remove the bleeding varices.
5. Liver transplant: In case of end stage liver disease, transplantation of the liver is the only option [10].

Higher mortality and morbidity rates are reported in patients with severe and persistent gastrointestinal hemorrhage. 90% of complicated cases (due to cirrhosis) of portal hypertension cause variceal hemorrhage.

The mortality rate of the patients who show the first episode of variceal hemorrhage is around 50%, while that with known diagnosis of esophageal varices is 30%.

Patients who report at least one episode of bleeding from the esophageal varices have 80% chances of re-bleeding within 1 year. In patients with esophageal varices, complications arising from immune, cardiovascular, pulmonary, cardiovascular systems contribute to around 20-65% of the deaths [5].

Complications

Common complications associated with portal hypertension are hepatic encephalopathy, aspiration pneumonia, sepsis, renal failure, cardiomyopathy, arrhythmias and hypotension.

Cirrhosis of the liver is the most important cause of portal hypertension. Cirrhosis is the aftermath (healing) of the liver injury which is caused by hepatitis, or excessive alcohol consumption. The scar in the liver, which is caused due to cirrhosis, blocks the flow of blood through this organ affecting its function.

There are some other causes of portal hypertension namely:

1. Blood clots in the portal vein 
2. Blockage of the veins 
3. Schistosomiasis: Parasitic infection
4. Focal nodular hyperplasia [2]

Portal hypertension is the most common manifestation of the liver. In the United States, the deaths associated with the liver cirrhosis (of which portal hypertension is a manifestation) is around 30,000. The international data for portal hypertension is not known, though 30% and 70% of patients with compensated and decompensated cirrhosis respectively suffer from portal hypertension at the time of diagnosis.

In Sub-Saharan Africa, Sudan and Egypt, the most common cause of portal hypertension is Schistosomiasis, while in South America, the Far-East and Southeast Asia, hepatitis B contribute to this condition.

More than 60% of the patients with cirrhosis (which eventually causes portal hypertension) are men; hence gender plays a significant important role in the etiology of the disease. Among children, portal vein thrombosis and secondary biliary cirrhosis contribute to esophageal varices [3] [4].

Portal vein carries the blood from the large and small intestine, stomach and spleen to the liver. Any obstruction of this vein can cause complications leading to portal hypertension.

This change causes an increase in the venous pressure, leading to development of collateral circulation which diverts the blood to the systemic veins. High portal pressure is responsible for the development of the portosystemic collaterals, including esophageal varices [7] [8] [9].

In patients with increased risk of portal hypertension, beta-blockers must be used to prevent the first variceal hemorrhage. To prevent the variceal re-bleeding, the combination of non-selective beta-blockers and a nitrate has been shown to be effective [11].

When there is an increase in blood pressure in the system of veins referred to as a portal system, it is called portal hypertension.

Normal portal pressure ranges between 5 mmHg and 10 mmHg. Generally a portal blood pressure of greater than 12 mmHg causes complications such as ascites and varices. Two factors that contribute to the development of portal hypertension are vascular resistance and blood flow [1].

Definition

Portal hypertension is the elevation of the blood pressure in the portal vein. The portal vein is vital for the normal functioning of the body.

Causes

Obstruction in the portal vein (the blood vessel that carries blood from the intestines, stomach and spleen to the liver) leads to the development of collateral circulation, causing portal hypertension.

Symptoms

Though there are no specific symptoms of the disease, blood in the stool or in vomit can be considered as reason enough to visit the doctor. Some of the other symptoms of portal hypertension are

Diagnosis

Diagnosis of the disease can be done by blood-tests, X-rays and endoscopic examination for the presence of ascites and/or varices.

Treatment

Though the treatment of the disease remains a challenge, management strategy of disease is focused on the prevention of the complications. Beta-blockers and lactulose are some medications which are prescribed to patients with portal hypertension. Treatment with endoscopic therapy has been proved to be most effective. 

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