What bodily change is primarily caused by portal hypertension due to liver cirrhosis?

Fluid accumulation in the abdomen, known as ascites, is primarily caused by portal hypertension due to liver cirrhosis. This condition occurs when the liver becomes scarred and hardened, leading to increased resistance to blood flow through the portal vein. The elevated pressure in the portal vein results in fluid leaking from the blood vessels into the abdominal cavity. This accumulation can contribute to significant abdominal swelling and discomfort for the patient.

Ascites is a common complication of cirrhosis and reflects the body's inability to manage fluid balance effectively due to liver dysfunction. The liver plays a crucial role in producing proteins such as albumin, which help maintain oncotic pressure and keep fluid within the vascular system. When the liver's function is compromised, as in cirrhosis, there is reduced albumin production, leading to fluid shifting into the abdominal cavity, which is a hallmark of portal hypertension.