Peritonitis refers to a acute inflammation of the peritoneum, membrane covering the abdominal cavity. Most often of infectious origin, peritonitis constitutes a medical emergency because it can be life-threatening.

Peritonitis is a acute inflammatory disease in theabdomen. It occurs more exactly at the level of the peritoneum, the membrane which surrounds the viscera of the abdominal cavity.

Depending on the extent and course of the inflammation, peritonitis can be considered:

• localized peritonitis ;
• generalized peritonitis.

This inflammation can also be classified according to its origin. There are two main types:

• primary peritonitis which is due to spontaneous infection with the initial absence of intraabdominal lesions;
• secondary peritonitis, the most common, which is caused by infection due to an intraabdominal lesion and the presence of an intraabdominal infectious focus.

Peritonitis is most often of infectious origin.

When the infection of the peritoneum is spontaneous, the peritonitis is said to be primary and may be due to different pathogenic strains. A distinction is made in particular between pneumococcal peritonitis and tuberculous peritonitis.

Representing 90% of acute inflammation of the peritoneum, secondary peritonitis can be caused by:

• intra-abdominal infection or perforation, such as appendicitis, perforation of a peptic ulcer, sigmoid diverticulitis, or cholecystitis;
• a post-operative event, which can occur in the event of intraoperative contamination or anastomotic disunity;
• a post-traumatic event, which can be a penetrating wound, closed trauma with perforation, digestive ischemia, endoscopic perforation, or perforation by a foreign body.

Peritonitis can be localized or spread throughout the body. This is called sepsis. Generalized peritonitis is a medical emergency because it engages the vital prognosis.

Peritonitis is characterized by the occurrence of intense abdominal pain, localized or generalized, of sudden or progressive onset. This abdominal pain is associated with a contracture of the muscles of the abdominal girdle. Rigid, toned, permanent and painful, this abdominal contracture is often referred to as a “wood belly”.

In addition to pain in the abdomen, peritonitis can present with other symptoms such as:

• vomitings ;
• stopping feces;
• diarrhea;
• infectious signs such as fever;
• great fatigue;
• a deterioration of the general condition.

The diagnosis of peritonitis may require different examinations such as:

• a clinical examination to assess perceived symptoms;
• blood tests to check for the presence of pathogens;
• medical imaging tests, such as an x-ray or ultrasound, to visualize the abdominal cavity.

In case of spontaneous infection, primary peritonitis requires hospitalization to find and treat the pathogen. Before the infectious strain is identified, provisional antibiotic therapy is usually put in place.

Like primary peritonitis, secondary peritonitis requires hospitalization and antibiotic therapy. However, it is also often based on surgical treatment which consists of removing the intraabdominal infectious site. The surgical intervention depends on the origin and the course of the peritonitis. It can for example be:

• an appendectomy, which is a complete removal of the appendix;
• a suture of a peptic ulcer;
• a gastrectomy, which is a partial or total removal of the stomach;
• a colectomy, which is the removal of the colon.

Surgical treatment for secondary peritonitis is usually accompanied by peritoneal toilet, which removes infected peritoneal fluid.