Causes of Ascites in Children

Children's physical health is an issue that the family is most concerned about. If there is a problem with the child's body, parents will definitely be very worried and don't know how to deal with it. Therefore, we recommend that parents and friends must pay attention to taking good care of children's bodies in daily life to help children prevent disease invasion. Below we will introduce to you the causes of ascites in children.

1) Increased portal vein pressure: Under normal circumstances, the hepatic sinusoidal pressure is very low (0-2 mmHg). When portal hypertension occurs, the hepatic sinusoidal hydrostatic pressure increases (portal vein pressure of 10 mmHg is the basic condition for the formation of ascites), and a large amount of fluid flows into the Disse space, causing excessive production of hepatic lymph fluid. The volume of lymph in patients with cirrhosis is often 20 times that of normal people. When the thoracic duct cannot drain the excessive lymph fluid, it leaks directly from the liver capsule into the abdominal cavity to form ascites. Increased sinusoidal pressure can also cause activation of intrahepatic pressure receptors, which, through the hepatorenal reflex, reduces renal sodium excretion and aggravates water and sodium retention.

2) Visceral artery dilation: In the early stages of cirrhosis, visceral blood vessels dilate, maintaining effective blood volume within a normal range by increasing cardiac output and heart rate. In the advanced stage of cirrhosis, visceral artery dilation becomes more obvious, resulting in a significant decrease in effective arterial circulating blood volume and a drop in arterial pressure, which in turn activates the sympathetic nervous system, the renin-angiotensin-aldosterone system, and increases the release of antidiuretic hormone (ADH) to maintain arterial pressure, causing renal vasoconstriction and sodium and water retention. Portal hypertension interacts with visceral vasodilation to alter intestinal capillary pressure and permeability, favoring fluid accumulation in the peritoneal cavity.

3) Decreased plasma colloid osmotic pressure: Patients with cirrhosis have reduced intake, decreased liver reserve function, and decreased ability to synthesize albumin, which leads to decreased plasma albumin and, in turn, decreased plasma colloid osmotic pressure. A large amount of fluid enters the tissue space, forming peritoneal effusion.

4) Other factors: Relative deficiency of plasma central natriuretic peptide and decreased sensitivity of the body to it, reduced inactivation of estrogen, increased secretion of antidiuretic hormone leading to drainage dysfunction and decreased secretion of prostaglandins, resulting in renal vasoconstriction, decreased renal perfusion, and redistribution of renal blood flow, all of which are related to the formation and persistence of ascites.

In the above article, we introduced one of the things that family members are most concerned about, that is, the physical health of children. Children are prone to various diseases, so parents must protect their children's bodies. The above article introduces in detail the causes of ascites in children.