Influence of ultrasonography on clinical decision making in suspected acute appendicitis in adults

Indices of diagnostic abdominal ultrasonography in acute appendicitis: influence of gender and physical constitution, time evolution of the disease and experience of radiologist

OBJECTIVE

To assess the value of abdominal ultrasonography in the diagnosis of acute appendicitis and the influence of gender, physical constitution, experience of the radiologist and the time evolution of the disease on the results of diagnostic indices.

METHODS

We prospectively evaluated 156 patients with clinical diagnosis of acute appendicitis who underwent laparoscopic appendectomy and abdominal ultrasonography, together with pathology of the excised appendices. Patients were allocated in relation to BMI in both groups (below or above 25 kg/m²) and radiologists, in three groups according to their professional experience (less than five years, between five and 10 years and more than 10 years). The survey also assessed the influence of gender and time of disease progression using the median of 36 hours.

RESULTS

The sensitivity and specificity of abdominal ultrasonography for diagnosing appendicitis were 64.9 and 72% respectively. Gender, body mass index, length of experience of the radiologists in the three groups and time of onset of symptoms showed no significant differences in the establishment of sonographic diagnosis of acute appendicitis.

CONCLUSION

The abdominal ultrasonography showed low sensitivity and specificity and little contribution to the diagnosis of acute appendicitis. Gender, physical constitution, the experience of the radiologist and time of onset of symptoms did not affect the outcome of the sonography.

Prospective validation of two systems of classification for the diagnosis of acute appendicitis

OBJECTIVES

The objectives of this study were (1) to validate the Alvarado score and pediatric appendicitis score (PAS) in a prospectively identified pediatric cohort and (2) to assess abdominal ultrasonography (AUS) as a tool to increase the diagnostic reliability of both scores.

PATIENTS AND METHODS

Prospective study conducted from January 10, 2008, to January 1, 2009. All patients attended at the emergency department with suspected acute appendicitis (AA) who had a blood sample collected were included. Items from both scores were recorded. The performance of an AUS, the decision to admit the patient, and the therapeutics were decided by the physician, disregarding the scores values. Nonadmitted patients were contacted by telephone.

RESULTS

Ninety-nine patients were included. Mean age was 11 years, and 62.6% were males. Appendectomy was performed in 44.4% patients. The area under the receiver operating characteristic curve for the Alvarado score was 0.96 and that for PAS was 0.97. Not a single patient with an Alvarado score less than 5 or PAS less than 4 had AA. All patients with an Alvarado score greater than 8 or PAS greater than 7 had AA. For both scores, the optimum cutoff point was 6 (sensibility of 90.4% and specificity of 91.2% for the Alvarado score and sensibility of 88.1% and specificity of 98.2% for PAS). Abdominal ultrasonography was performed on 31 patients (sensibility of 84.6% and specificity of 94.4%). We studied the value of scores and AUS together. Assuming an Alvarado score from 1 to 4 and PAS from 1 to 3 as no AA, an Alvarado score from 9 to 10 and PAS from 8 to 9 as AA, and proceeding according to the AUS for intermediate values, a sensibility of 93.3% and 97.2% and a specificity of 100% and 97.6%, respectively, were obtained.

CONCLUSIONS

Both scores are a useful tool in the evaluation of children with possible AA. For extreme values of scores, the results really ensure their use in the emergency department. The AUS can help on decision making for intermediate values.