SIRS Criteria — Free Online Calculator
SIRS Criteria
Note: SIRS + suspected infection = Sepsis (by the 1992 ACCP/SCCM definition). The Sepsis-3 definition (2016) uses SOFA criteria instead.
SIRS Score
0
SIRS criteria NOT met
About This Calculator
The Systemic Inflammatory Response Syndrome (SIRS) criteria identify patients with a systemic inflammatory response. Meeting ≥ 2 criteria defines SIRS. While SIRS is non-specific and can result from infection, trauma, burns, or pancreatitis, SIRS with a suspected source of infection was historically used to define sepsis (prior to Sepsis-3). The SIRS criteria remain widely used for early identification of critically ill patients.
Formula
Interpretation
| Score | Interpretation |
|---|---|
| 0 – 1 | SIRS criteria not met |
| 2 | SIRS positive |
| 3 | SIRS positive |
| 4 | SIRS positive (all criteria met) |
References
Frequently Asked Questions
Is SIRS still used to define sepsis?
No. Since the Sepsis-3 definition in 2016, sepsis is defined by SOFA score ≥ 2 with suspected infection, not by SIRS criteria. However, SIRS criteria are still widely used for early identification of systemic inflammation and in some clinical protocols.
Can SIRS be positive without infection?
Yes. SIRS is a non-specific inflammatory response. It can be triggered by trauma, surgery, burns, pancreatitis, autoimmune disorders, and many other non-infectious conditions.
What is the sensitivity of SIRS for detecting sepsis?
SIRS criteria are highly sensitive (~90%) but have poor specificity for infection. Many non-infected ICU patients meet SIRS criteria. Conversely, some septic patients (up to 12%) may not meet SIRS criteria, which was one reason for the Sepsis-3 revision.
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⚠ Medical Disclaimer
This tool is for educational and informational purposes only. It is not intended to replace professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare professional for clinical decisions.