Ascites (commonly known as watery belly) is an accumulation of fluid in the peritoneal cavity, that is, the space between the peritoneum (abdominal wall) and the abdominal organs. 
The peritoneum produces a fluid that acts as a lubricant and allows the abdominal organs to slide one over the other.

Sometimes fluid accumulates between the inner and outer layers of the peritoneum and this phenomenon is called ascites.

The ascites caused by cancer is called malignant ascites and concerns about 10% of people with ascites.

Malignant ascites appears more often in people with breast cancer , colon cancer , gastrointestinal tract ( stomach and intestines), pancreas , ovary and uterus .


Classification of ascites

1. Biliary ascites is a fluid accumulation with bile pigments and liquid bile; 
2. Chylous ascites is caused by a deposit of lymphatic and whitish fluid, caused by traumatic, inflammatory or neoplastic lesions of the large lymphatic vessels; 
3. Hemorrhagic ascites occurs if there is blood inside the peritoneal cavity.

The ascitic fluid can be:
1. Transudate, if derived from the increase of pressure in the portal vein due to  cirrhosis ; in this case there is little protein in the liquid. 
2. Exudate, if derived from inflammatory phenomena that alter the permeability of the cell membrane that causes a part of the liquid contained in the blood. 
In exudate the amount of proteins, such as albumin, is similar to that of blood; the difference is less than 1 mg / dl.


Causes of ascites

Malignant ascites represent about 15% of cases.

Among the most frequent causes are:

  • Hepatical cirrhosis,
  • Malignant tumors of the gastrointestinal tract ( stomach , colon , pancreas , primary hepatocellular carcinoma , and metastatic liver cancer ),
  • Ovarian cancer : Meigs syndrome is a rare complication of ovarian cancer and produces ascites disproportionate to tumor size and pleural effusion , usually unilateral,
  • Hodgkin’s lymphoma and non-Hodgkin’s lymphoma,
  • Metastatic carcinoma within the abdominal cavity (peritoneal carcinomatosis),
  • Heart failure ,
  • Nephrotic syndrome (rare),
  • Tuberculosis ,
  • Pancreatitis ,
  • Other rare causes, including hypothyroidism ,
  • Iatrogenic hyperstimulation as a result of in vitro fertilization procedures.


Ascites symptoms

There is a distinction between patients who develop ascites due to  cirrhosis and diseases of the liver and those who develop it by inflammation of the peritoneumcaused by cancer. 

Liver disease can be relatively painless, while cancer patients can experience a lot of pain. 
The other symptoms are similar 
There is a swollen belly due to fluid buildup. This can make it difficult to work the diaphragm (smooth muscle that separates the chest from the abdomen) that assists breathing, causing shortness of breath .
While a tight, fluid-filled abdomen is easy to recognize, at first the amount of ascitic fluid may be small and difficult to detect. 
When the amount of fluid increases, the patient feels a feeling of fullness or weight in the abdomen.


Cirrhosis of the liver

Ascites is the most frequent sign in patients with cirrhosis, and when it does occur, life expectancy is generally reduced. 
In about 75% of patients with ascites, the cause is cirrhosis and about 50% of patients with cirrhosis develop ascites over a 10-year period of controls. 
The retention of liquids (mostly ascites, but also peripheral edema and pleural effusion) is the most common complication of liver disease in the terminal stage. 
The quality of life of patients with ascites and cirrhosis is considerably aggravated and associated with an unfavorable prognosis; the 1-year survival rate is 85% and the 5-year survival rate is 56%.
Attention: the patient with a very long history of stable cirrhosis who later develops ascites should make controls for possible hepatocellular carcinoma.


Complications and consequences of ascites

  • In cirrhosis of the liver, not only does fluid accumulate in the abdominal cavity, but swelling in the legs , easy bruising , breast enlargement and confusion due to encephalopathy (brain disease) can occur .
  • If ascites is caused by heart failure , shortness of breath  and swelling in the legs ( edema ) may occur . 
    Shortness of breath tends to worsen with activity and in lying position (orthopnea). 
    Patients with ascites due to heart failure tend to wake up in the middle of the night with paroxysmal nocturnal dyspnea .
  • Cancer patients complain of pain , weight loss and fatigue  along with abdominal distension.
  • Those who suffer from spontaneous bacterial peritonitis ( peritoneal infection ) develop fever and abdominal pain.


Diagnosis of ascites

For the diagnosis of ascites, the doctor can examine the abdominal area and ask questions about possible recent symptoms. 
The following tests may help diagnose ascites:

  • Blood tests , useful values ​​are: AST, ALT (liver transaminases), a  complete blood count  for blood, urea, and creatinine to assess renal function, blood glucose, and electrolytes ( potassium , chlorine and sodium);
  • The ultrasound  which measures the abdominal fluid, see a possible clot in the portal vein and also serves to diagnose the Budd-Chiari syndrome;
  • Paracentesis (removal and analysis of fluid from the abdomen with a syringe) can be performed after the fluid is discovered to know the cause (eg, infection, cancer, or other disease). The most important values ​​of ascitic fluid are proteins (to exclude cirrhosis) and white blood cell counts to see if the patient is infected.


Treatments for ascites

Following the patient 
Treatment of ascites depends on the cause. In most patients, cirrhosis that causes portal hypertension is the leading cause. 
If portal hypertension is the cause of ascites, it is usually treated with diuretic medications (eg, Lasix) and avoiding eating salt, which is also effective. 

In contrast, ascites caused by peritoneal inflammation or cancer do not respond to diuretics and the non-salt diet. 
It is possible to try the treatment without hospitalization. However, hospitalization may be necessary in three situations: 

1. For research on the cause of liver disease; 
2. To teach the patient to prepare a diet low in sodium;
3. To closely monitor the concentration of creatinine, urea nitrogen, and electrolytes in the blood and urine.

In the hospital it is important to measure body weight, fluid intake and fluid output. Restriction of fluids is only necessary if the blood sodium concentration falls below 120 mmol / l. 
It is important to determine sodium balance, which can be approximated by controlling intake (diet, medication containing sodium and intravenous solutions) and elimination through urine. 
A negative sodium balance is a signal that predicts a weight loss. 

A reasonable goal for a patient without peripheral edema is a negative sodium balance with a weight loss of 0.5 kg per day.


Medications for ascites

Most patients with cirrhotic ascites respond to diuretics and sodium dietary restriction. 
The combination of spironolactone and furosemide is the most effective for rapidly decreasing ascites. 
The starting dose is 100 mg of spironolactone and 40 mg of furosemide in the morning. 
If there is no decrease in body weight or an increase in urinary sodium excretion after two or three days, it is advisable to increase doses of the medicines. 
Drug doses may be increased to 400 mg spironolactone and 160 mg furosemide per day. 

Only 10% of patients do not respond to this therapy (diuretics plus sodium dietary restriction).
Patients who respond to this treatment for ascites do not need anything else as long as it continues to be effective.

ascites Treatment options for drug-resistant ascites include:

  • Paracentesis and Therapy Paracentesis
    of up to 1 liter of fluid can alleviate respiratory distress caused by fluid pressure in the abdomen. 
    Removal of larger volumes and total paracentesis (the largest reported volume is 22.5 l) are discussed. 
    Some authors argue that the injection of 10 g of intravenous albumin for each liter of ascitic fluid removed serves to avoid a reduction in plasma volume, some abnormalities of electrolytes and creatinine.
  • TIPS (transjugular portosystemic intrahepatic shunt) is a medical procedure that creates an artificial canal to connect the portal vein to the hepatic vein.
  • Liver transplant


Prognosis of the patient with ascites or watery belly

Patients with cirrhosis who develop ascites have a 5-year survival rate of 50%; for patients with refractory ascites, the 1-year survival rate is less than 50%. 

For most patients with cirrhosis, therapeutic paracentesis and diet change without a liver transplant may improve quality of life but do not significantly improve long-term survival. 

Malignant ascites indicate the spread of the disease and poor prognosis.

Read too