Acute Abdomen

The term acute abdomen refers to the signs and symptoms of abdominal pain and tenderness. This situation often represents an underlying surgical problem that requires prompt diagnosis and surgical treatment. While the ready availability of diagnostic studies such as computed tomography (CT) scans or magnetic resonance imaging (MRI) has added greatly to our ability to accurately diagnose most of the conditions responsible for the acute abdomen, the mainstay for diagnosis remains a good history and physical exam complemented by laboratory and radiologic studies as appropriate. In addition, many conditions that are not surgical or even centered in the abdomen can also cause this presentation. A prompt and accurate diagnosis is necessary in order to select the appropriate therapy, which may be a laparoscopy or laparotomy.

Age, gender, and a history of prior abdominal surgical procedures are associated with different problems causing the acute abdomen. Certain diseases like appendicitis and mesenteric adenitis are more common in the young while biliary tract disease, diverticulitis, and intestinal ischemia are more common in older populations. Chapter 67 deals with abdominal pain in children.

Numerous problems that are not surgical may also present as an acute abdomen. These include endocrine and metabolic issues, hematologic problems, and disorders caused by toxins or drugs ( Box 46.1 ). ^, Endocrine and metabolic diagnoses include uremia, diabetic or Addisonian crisis, acute intermittent porphyria, hyperlipoproteinemia, and hereditary Mediterranean fever. Hematologic disorders include sickle cell crisis and acute leukemia. Toxins and drugs that can cause acute abdominal pain are lead and other heavy metal intoxications, narcotic withdrawal, and black widow spider bites. All of these need to be considered when evaluating a patient with sudden onset abdominal pain.

The need for prompt surgical treatment of those causes of the acute abdomen that require operation mandates an expeditious evaluation so that the proper therapy can be carried out ( Box 46.2 ). A focused history and physical examination and indicated laboratory and imaging studies will then allow for the correct diagnosis and guide appropriate therapy. While imaging studies have added greatly to the accuracy of the diagnosis of causes of the acute abdomen, a thorough history and careful physical examination remain the mainstays of evaluation.