Alvarado scoring system in prediction of acute appendicitis.

OBJECTIVE To evaluate the diagnostic accuracy of Alvarado score for the prediction of acute appendicitis. STUDY DESIGN Analytical study. PLACE AND DURATION OF STUDY This study was carried out in the Department of Surgery, Pakistan Institute of Medical Sciences (PIMS), Islamabad, during the period from January 15, 2009 to July 15, 2010. METHODOLOGY The study included all adult patients of either gender who presented with clinical findings suggestive of acute appendicitis, who were assigned Alvarado score of < 4 pre-operatively and subsequently underwent emergency appendicectomy with histological examination of the resected specimens. Based on the Alvarado score, the patients were stratified into two groups. i.e. Group I (with a score of > 7) and Group II (with a score of 5-7). Alvarado score was compared with the histopathology. The data was subjected to statistical analysis to measure the objective. RESULTS The overall sensitivity, specificity, positive predictive value and negative predictive value of Alvarado score for acute appendicitis were 66%, 81%, 96%, 29% respectively. The sensitivity was higher though not significant, for males with a score over 7 than females with similar scores (97% vs. 92%). However, for scores less than 7, sensitivity among males was significantly higher than females with similar scores (79% vs. 61%; p < 0.05). CONCLUSION The presence of a high Alvarado score in adult males is highly predictive of acute appendicitis, however, in women of child bearing age other causes of similar clinical presentation lead to a low diagnostic accuracy of the score.