Diagnostic score in acute appendicitis. Validation of a diagnostic score (Lintula score) for adults with suspected appendicitis

We have previously constructed and validated a diagnostic score to reduce the negative appendicectomy rate in children with suspected appendicitis. The purpose of this prospective study was to validate the diagnostic score (Lintula score) in adults with suspected appendicitis.

A total of 177 patients with suspected appendicitis were randomly assigned to either the appendicitis-score-group (n = 96) or the no-score-group (n = 81). The management decision was based on the use of the diagnostic scoring system in the appendicitis-score-group and on a sole clinical assessment in the no-score-group. The main diagnostic performance parameters were the diagnostic accuracy, specificity and sensitivity, the positive and negative predictive values, and the rate of negative appendicectomies.

There was no difference between the appendicitis-score-group and the no-score-group in the diagnostic accuracy (92% vs. 91%; P = NS) and the negative appendicectomy rate (13% vs. 16%). Following repeated clinical examination, the diagnostic accuracy improved in both groups, 74% vs. 92% in the appendicitis-score-group (P = 0.01), and 84% vs. 91% in the no-score-group (P = 0.01). The application of the Lintula score yielded a higher positive predictive value (98% vs. 84%; P = 0.02) and specificity (98% vs. 84%; P = 0.028), but a lower negative predictive value (86% vs. 100%; P = 0.016) and sensitivity (87% vs. 100%; P = 0.022) than unaided clinical examination in the no-score-group. There were no differences in terms of the length of hospital stay, rate of complications and appendiceal histology between the two groups.

The use of the acute appendicitis score developed for paediatric patients seems to provide some benefits compared to an unaided clinical diagnosis and may, thus, be a useful diagnostic tool for general surgeons.