What is the difference between ascites and peritonitis?

Peritonitis is an infection of the peritoneum, the sack which surrounds the peritoneal cavity. It may be caused by a appendicitis, when the infected appendix ruptures allowing spread of infection.

Ascites is an excessive accumulation of peritoneal fluid in the peritineum. It can be caused by cirrhosis which leads to portal hypertension. Ascites is therefore a symptom of liver failure. It notabley occurs in cases of Kwashiorkor.