Pulmonary & infection

SIRS criteria

Count the four original adult systemic inflammatory response criteria.

Intended population: Adults; can reflect infectious or noninfectious inflammation.

SIRS is nonspecific and does not diagnose sepsis. Sepsis can be present with fewer than two criteria.
Evaluate suspected infection, organ dysfunction, and clinical instability independently. This is not the pediatric SIRS definition.

Adult patient; criteria reviewed using observed values

Temperature >38°C or <36°C

Heart rate >90/min

Respiratory rate >20/min OR arterial PaCO₂ <32 mmHg

WBC >12,000/µL OR <4,000/µL OR immature neutrophils >10%

Sources and scoring references

ACCP/SCCM consensus: original adult SIRS criteria (1992) ↗2026 Surviving Sepsis Campaign adult guideline ↗

Implementation references reviewed October 28, 2026. Verify applicability and unusual or treatment-changing results against the linked references and local guidance.