[Ultrasonography and the Alvarado score in the diagnosis of acute appendicitis: impact on the negative appendectomy rate].

OBJECTIVES

To establish the negative appendectomy rate (NAR) after patients with acute abdomen were evaluated with the Alvarado score and compare it to the NAR in patients evaluated with abdominal ultrasound.

MATERIAL AND

METHODS

Cross-sectional, retrospective, descriptive study in patients who underwent emergency surgery for suspected acute appendicitis in a tertiary-care hospital over a period of 1 year.

RESULTS

A total of 225 patients were included. The NAR was 7.11% for the series. An Alvarado score of 5 or more had an odds ratio (OR) of 7.46 (P=.0002) for acute appendicitis; sensitivity was 94.2%. Ultrasound findings consistent with acute appendicitis had an OR of 3.58 (P=.0125) for the diagnosis; the NAR was 5%.

CONCLUSION

The high sensitivity of an Alvarado score of 5 or more supports using this tool to evaluate all patients who come to the emergency department with pain in the right iliac fossa. With scores of 7 or more the NAR falls to 3%. Abdominal ultrasound is a rapid, inexpensive diagnostic procedure associated with a low NAR.