However, the most important diagnostic measure in patients with severe abdominal pain often is expeditious exploratory laparotomy. Some relatively common diseases must be considered in the differential diagnosis of acute abdominal pain. Gastroenteritis is likely if family members or associates have had recent similar complaints. Symptoms include colicky pain, nausea, vomiting, and diarrhea, which may be accompanied by mild abdominal tenderness that never becomes localized. Gastroenteritis is self-limited.
Herpes zoster can cause severe pain that precedes the typical rash.
The pain can be confusing, particularly if the nerves in the right lower quadrant are involved in a patient whose appendix has not been removed. Pneumonia can lead to diffuse abdominal pain without localized abdominal tenderness. Acute MI may be accompanied by poorly localized abdominal pain. Drug addiction or withdrawal may produce severe colicky pains that suggest intestinal obstruction. Anticoagulant use or severe coughing can lead to a hematoma of the abdominal wall or rupture of the deep epigastric artery or vein, events that produce local pain and tenderness.