What Is Peritonitis? - Definition, Symptoms & Treatment

Instructor: Virginia Rawls

Virginia has a master' degree in Education and a bachelors in Sports Medicine/athletic Training

Learn the definition of peritonitis, the symptoms of this condition, and treatment options available to patients that have peritonitis.

What Is Peritonitis?

If you pick the word apart, peritonitis literally means 'infection of the peritoneum.' Before we can explore peritonitis, we need to do a quick anatomy review. The peritoneum lines the abdominal cavity and covers the abdominal organs. The picture below shows all of the body cavities, including the abdominal cavity.

body cavities

The peritoneum is a serous membrane that covers both the abdominal cavity and the organs in the abdominal cavity. A serous membrane is a type of tissue that contains a small amount of serum, or fluid, that makes it slippery. There are two types of peritoneum. The parietal peritoneum lines the inside of the abdominal cavity, and the visceral peritoneum covers the organs in the abdominal cavity.

The parietal and visceral peritoneum work together to reduce friction between the abdominal wall and abdominal organs. Because these are both serous membranes, they are slippery tissues that will allow the organs and the abdominal wall to slide past each other without damaging each other when your body moves. The picture below highlights the parietal peritoneum.

parietal peritoneum

Having trouble picturing this? Think about the engine in your car and how you have to make sure that there is oil in it. The oil helps all of the moving parts be able to slide past one another without having any friction. If the oil wasn't there, the engine parts would stick to each other and wouldn't work properly. The parietal and visceral peritoneum work in a similar way. If the parietal and visceral peritoneum didn't exist, the organs in your abdomen and the abdominal wall would stick together and not function properly.

Causes of Peritonitis

So, now we know what the peritoneum is and that peritonitis is an infection of the peritoneum. But how does this happen? Peritonitis can be caused by a few different things. Open abdominal wounds and tears in the peritoneum are mainly what lead to peritonitis. These openings and tears can allow bacteria or fungi inside the body. Ruptures of abdominal organs that are infected can also lead to infection of the peritoneum. When these organs break open, they allow the bacteria inside to implant in the peritoneum. Other causes include stomach ulcers, liver disease, kidney disease, and infection of the pancreas.

Symptoms of Peritonitis

Symptoms of peritonitis will vary depending on how long the infection has been in the body. This is a very serious condition. If left untreated, the infection can get into the blood stream and lead to organ shut down and even death of the patient.

Symptoms of peritonitis include:

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