Score for acute appendicitis (MANTRELS).

What it is and when to use it

The Alvarado Score is a clinical prediction rule that estimates the likelihood of acute appendicitis in patients with abdominal pain. It totals 10 points from eight variables (the MANTRELS mnemonic): Migration of pain to the right iliac fossa, Anorexia, Nausea or vomiting, Tenderness in the right iliac fossa, Rebound pain, Elevated temperature (≥37.3 °C), Leukocytosis, and left Shift of the white-cell count. Leukocytosis and right iliac fossa tenderness score 2 points each; the remaining items score 1 point. It is used as a screening and risk-stratification tool in the initial assessment of abdominal pain suspicious for appendicitis.

How to interpret it

The score ranges from 0 to 10. As a general guide: 1-4 points indicates low probability of appendicitis (discharge with follow-up may be considered); 5-6 points indicates intermediate or compatible probability, where observation and/or imaging (ultrasound or CT) is usually recommended; and 7-10 points indicates high probability, warranting surgical evaluation or imaging depending on context. The most widely used threshold to reasonably rule out appendicitis is a score ≤4. The exact cut-off and resulting management vary with local protocol, age, and sex.

Limitations and when not to use it

The score was derived and validated predominantly in adults with acute abdominal pain. Its performance is more limited and less consistent in children, the elderly, pregnant women, and women of childbearing age (where gynecological differentials lower specificity). It is not a definitive diagnostic test: a low score does not fully exclude appendicitis, nor does a high score confirm it, and it does not replace clinical judgment or imaging. A frequent misuse is relying on it to proceed directly to surgery without imaging in intermediate cases, or applying it outside the setting of acute abdominal pain.

Frequently asked questions

What Alvarado score indicates appendicitis?

A score of 7-10 indicates high probability of appendicitis and warrants surgical evaluation or imaging; 5-6 is intermediate and usually requires observation or imaging; 1-4 indicates low probability.

What does the MANTRELS mnemonic stand for?

Migration of pain, Anorexia, Nausea/vomiting, Tenderness in the right iliac fossa, Rebound pain, Elevated temperature, Leukocytosis, and Shift to the left. These are the eight variables of the score.

Is the Alvarado score valid for children and pregnant women?

It was validated mainly in adults; its performance is less reliable in children, pregnant women, and women of childbearing age, so it should be complemented with imaging and clinical judgment.