Acute abdominal pain in the elderly. STUDY OBJECTIVES: To determine the incidences of both specific diagnosis and surgical diseases in patients more than 65 years old who present to the emergency department with nontraumatic abdominal pain of less than one week's duration, and to determine the ED staff's ability to diagnose and triage elderly patients with acute abdominal pain. DESIGN: A 12-month retrospective review of all elderly patients who presented to the ED with acute, nontraumatic abdominal pain. SETTING: A regional trauma center serving a predominately rural population in the Midwest. The ED has 55,000 patient visits yearly. MEASUREMENTS AND MAIN RESULTS: Of the 127 patients enrolled, 30 (24%) had no specific diagnosis made in the ED. Biliary tract disease (12%) and small bowel obstruction (12%) were the two most common specific diagnoses. Overall, 53 patients (42%) required surgery, usually during the initial hospitalization. In four cases, the postoperative diagnosis differed significantly from the ED diagnosis. Of the 74 patients (58%) who did not undergo surgery, 51 had follow-up information available. In 14 patients, the follow-up diagnosis differed from the original diagnosis, but most of these changes did not appreciably alter the treatment and outcome. CONCLUSIONS: The incidence of surgical disease is high in elderly patients with acute abdominal pain, and ED staff are able to diagnose and triage these patients accurately. 