Non-specific abdominal pain remains as the most common reason for acute abdomen: 26-year retrospective audit in one emergency unit.

Objective: Distribution of diagnoses causing acute abdominal pain (AAP) may change because of population aging, increased obesity, advanced diagnostic imaging and changes in nutritional habits. Our aim was to evaluate the diagnoses causing AAP during a 26-year period. Materials and methods: This was a retrospective cross-sectional cohort study in one emergency department (ED) covering population about 250,000. All patients admitted to the ED in 1986, 2003 and 2012 were evaluated from hospital electronic database. Demographic data, utilization of diagnostic tests, surgical treatment and discharge diagnosis were analyzed. Statistical data of population aging, obesity and alcohol consumption during 1980-2012 were obtained from national registers. Results: The AAP patients represented 10-20% of our total ED census. The most common causes of AAP were nonspecific abdominal pain (NSAP, 31-37%), acute appendicitis (11-23%), biliary disease (9-11%), bowel obstruction (5-7%), acute pancreatitis (4-8%) and acute diverticulitis (1-7%). The percentage of NSAP remained highest throughout the study period. Decrease in the number of acute appendicitis (from 23 to 11%; p < .0001), increase in acute diverticulitis (from 1 to 5%; p <= .0001) and acute pancreatitis (from 4 to 7%; p = .0273) was observed over time. The utilization of diagnostic imaging increased significantly (CT from 2 to 37% and US from 4 to 38%, p < .0001). Hospital mortality was very low (1-2%). Conclusions: NSAP is still the main differential diagnostic problem in the ED. Except acute appendicitis, distribution of specific diagnoses causing AAP remained rather stable through 26-year audit.