Emergency surgery
Alvarado Score for Acute Appendicitis
The Alvarado Score combines eight clinical and laboratory criteria to triage suspected appendicitis. Select the findings present to calculate the total score and suggested management pathway.
Total Alvarado score
0
Range 0–10
Scores below 5 make appendicitis less likely, but clinical judgement and serial exams remain essential.
Clinical context matters. Pregnancy, older adults, or atypical presentations may require imaging despite low scores.
How to Use This Calculator
Gather history, exam, and labs
Confirm symptoms, vital signs, and laboratory values. Each should reflect the current patient state.
Toggle present findings
Select every criterion observed. The calculator adds the corresponding points automatically.
Interpret the score in context
Use the suggested risk band as part of your overall decision making, not a standalone diagnosis.
Formula
Total Alvarado score = Σ(points for each positive criterion).
- MANTRELS mnemonic: Migration (1), Anorexia (1), Nausea/vomiting (1), Tenderness RLQ (2), Rebound pain (1), Elevated temperature (1), Leukocytosis (2), Shift to left (1).
- Maximum possible score is 10.
- Risk bands: 0–4 low, 5–6 equivocal, 7–8 probable, 9–10 very probable appendicitis.
Full Description
Developed in 1986, the Alvarado Score remains a quick bedside tool for stratifying appendicitis risk. It combines history, physical examination, and laboratory findings to help decide on observation versus imaging or surgical consultation. The score is especially helpful where CT or ultrasound access is limited, though imaging is often still recommended for intermediate scores.
Limitations include reduced accuracy in pregnant patients, older adults, and children under five. High scores do not confirm appendicitis; other right lower quadrant pathologies can mimic the presentation. Use serial examinations and imaging to avoid negative appendectomies or missed diagnoses.
Frequently Asked Questions
Is imaging required for high scores?
Many clinicians still perform imaging, but surgical evaluation may proceed directly when the score is ≥7 and clinical suspicion is high.
Can children use the same cutoffs?
Yes, though sensitivity is lower in young children. Consider adjunct tools (e.g., Pediatric Appendicitis Score) and pediatric-specific evidence.
What if some lab results are pending?
Use available data to calculate a partial score, then update once labs return. Document uncertainty when criteria cannot be verified.
Does a low score rule out appendicitis?
No. Clinical judgement prevails. Reassess if symptoms evolve, especially in high-risk populations or atypical presentations.