About the Alvarado Score Calculator
The Alvarado score, also known by the mnemonic MANTRELS, is a 10-point clinical score for suspected acute appendicitis. It combines three symptoms (Migration of pain to the right lower quadrant, Anorexia, Nausea or vomiting), three signs (Tenderness in the right lower quadrant, Rebound pain, Elevated temperature) and two laboratory findings (Leukocytosis and a Shift to the left in the neutrophil count).
Alfredo Alvarado published the score in 1986 after a retrospective study of 305 patients hospitalised with abdominal pain suggestive of appendicitis. Right lower quadrant tenderness and leukocytosis carried the most diagnostic weight and score two points each; every other item scores one. In his scheme, 5–6 points is compatible with appendicitis, 7–8 makes it probable and 9–10 very probable.
The score performs best at ruling appendicitis out when it is low, and it was derived in adults; it is less accurate in children, pregnant women and older adults. Imaging (ultrasound or CT) and surgical review remain central to the decision. This calculator supports clinical assessment and does not replace it.
With the default inputs, the alvarado score is 7 / 10. Change any value above to recalculate instantly.
How to use the alvarado score calculator
- 1Take a history for pain migration, appetite and nausea or vomiting.
- 2Examine for right lower quadrant tenderness and rebound, and record the temperature.
- 3Enter the white cell count and neutrophil percentage results.
- 4Read the total score and likelihood band, and combine it with imaging and surgical review.
Formula and method
Each MANTRELS item scores one point except right lower quadrant tenderness and leukocytosis, which score two because they had the highest diagnostic weight in the original study. Migration of pain, anorexia, nausea/vomiting, rebound pain, temperature of 37.3 °C or more and a left shift (neutrophils above 75%) each add one point.
Alvarado’s original interpretation: a total of 5 or 6 is compatible with appendicitis, 7 or 8 indicates probable appendicitis, and 9 or 10 very probable appendicitis. Scores of 4 or less make appendicitis unlikely. Later meta-analyses found the score is well calibrated in men, tends to over-predict in women and is less reliable in children.
- M, A, N
- Migration of pain, Anorexia, Nausea/vomiting
- T, R, E
- RLQ Tenderness (2), Rebound pain, Elevated temperature
- L, S
- Leukocytosis > 10,000/µL (2), Shift to the left
Worked examples
Typical presentation without fever
Migration (1) + anorexia (1) + nausea (1) + RLQ tenderness (2) + leukocytosis (2) = 7 points, which Alvarado classed as probable appendicitis.
All eight features present
Every item is positive, giving the maximum 10 points — very probable appendicitis.
Vague pain with normal bloods
Only nausea (1) and RLQ tenderness (2) are present, for 3 points — appendicitis is unlikely, though review is advised if symptoms change.
Equivocal case
Migration (1) + anorexia (1) + RLQ tenderness (2) + temperature ≥ 37.3 °C (1) = 5, an equivocal score compatible with appendicitis.
Frequently asked questions
What does MANTRELS stand for?+
Migration of pain, Anorexia, Nausea/vomiting, Tenderness in the right lower quadrant, Rebound pain, Elevated temperature, Leukocytosis and Shift of white cells to the left — the eight components of the Alvarado score.
What Alvarado score means appendicitis?+
In Alvarado’s original paper, 5–6 points was compatible with appendicitis, 7–8 probable and 9–10 very probable. No score confirms the diagnosis on its own; imaging or surgery provides confirmation.
How accurate is the Alvarado score?+
It is most useful for ruling appendicitis out: a score below 5 has high sensitivity in adults. Specificity at higher scores is moderate, and the score over-predicts appendicitis in women and performs less well in children.
Is there a version for children?+
Yes. The Pediatric Appendicitis Score (PAS) by Samuel uses similar items, adds cough, percussion or hopping tenderness, and uses a temperature cut-off of 38 °C. The AIR score is another validated alternative.
What temperature counts as elevated in the Alvarado score?+
An oral temperature of 37.3 °C (99.1 °F) or higher scores one point. The paediatric score uses a higher threshold of 38 °C.
For healthcare professionals and education only. This calculator implements a published formula or score but is not a diagnosis and does not replace clinical judgment. Verify inputs and results against the original source before using them in patient care.