|Other names||Surgical abdomen, acute abdomen|
|Peritonitis from tuberculosis|
|Specialty||Emergency medicine, general surgery|
|Symptoms||Severe pain, swelling of the abdomen, fever|
|Complications||Shock, acute respiratory distress syndrome|
|Causes||Perforation of the intestinal tract, pancreatitis, pelvic inflammatory disease, cirrhosis, ruptured appendix|
|Risk factors||Ascites, peritoneal dialysis|
|Diagnostic method||Examination, blood tests, medical imaging|
|Treatment||Antibiotics, intravenous fluids, pain medication, surgery|
Peritonitis is inflammation of the peritoneum, the lining of the inner wall of the abdomen and cover of the abdominal organs. Symptoms may include severe pain, swelling of the abdomen, fever, or weight loss. One part or the entire abdomen may be tender. Complications may include shock and acute respiratory distress syndrome.
Causes include perforation of the intestinal tract, pancreatitis, pelvic inflammatory disease, stomach ulcer, cirrhosis, or a ruptured appendix. Risk factors include ascites and peritoneal dialysis. Diagnosis is generally based on examination, blood tests, and medical imaging.
Treatment often includes antibiotics, intravenous fluids, pain medication, and surgery. Other measures may include a nasogastric tube or blood transfusion. Without treatment death may occur within a few days. Approximately 7.5% of people have appendicitis at some point in time. About 20% of people with cirrhosis who are hospitalized have peritonitis.
Signs and symptoms
The main manifestations of peritonitis are acute abdominal pain, abdominal tenderness, abdominal guarding, rigidity, which are exacerbated by moving the peritoneum, e.g., coughing (forced cough may be used as a test), flexing one's hips, or eliciting the Blumberg sign (a.k.a. rebound tenderness, meaning that pressing a hand on the abdomen elicits less pain than releasing the hand abruptly, which will aggravate the pain, as the peritoneum snaps back into place). Rigidity is highly specific for diagnosing peritonitis (specificity: 76–100%, positive likelihood ratio: 3.6). The presence of these signs in a patient is sometimes referred to as peritonism. The localization of these manifestations depends on whether peritonitis is localized (e.g., appendicitis or diverticulitis before perforation), or generalized to the whole abdomen. In either case, pain typically starts as a generalized abdominal pain (with involvement of poorly localizing visceral innervation of the visceral peritoneal layer), and may become localized later (with involvement of the somatic innervation of the parietal peritoneal layer). Peritonitis is an example of an acute abdomen.