What is the Alvarado score and is it useful in diagnosis?
Developed more than 20 years ago, the Alvarado score has found more widespread usage in the past decade.
It is a 10-point risk stratification system with points based on findings such as anorexia and right lower quadrant pain, as well as laboratory studies like leukocytosis and left shift of white blood cells (WBCs) (see online calculator at http://www.mdcalc.com/alvarado-score-for-acute-appendicitis).
The Alvarado Score is the most well known and most performed in validated studies, as it is simple, effective and easy to use.
It provides an accurate and consistent tool for ruling out appendicitis and identifying patients at higher risk. The score arose from a retrospective review of patients operated on due to suspicion of AA: Alvarado identified three symptoms (migration of pain in right iliac fossa, anorexia and nausea/vomiting), three physical signs (tenderness, rebound pain and elevation of temperature) and two laboratory findings (leukocytosis and shift of the formula to the left) to be useful in AA diagnosis, and assigned them a number according to their diagnostic weight. Counting the numbers of each indicator present for the patient we obtain a score: Alvarado found that:
Although scores of 7 to 10 predict a 93% appendicitis rate, it tends to over-predict the rates of appendicitis in women and has shown some inconsistencies in children. Its best use may be in ruling out appendicitis in those with low scores (less than 4).