SIRS Criteria (IPSCC — Age-Specific Thresholds Apply)major

Temperature AbnormalityCore temperature > 38.5°C (101.3°F) OR < 36°C (96.8°F)Heart Rate Abnormality (Age-Adjusted)Tachycardia: > 2 SD above normal for age (see normal HR by age below). OR Bradycardia: HR < 10th percentile for age in infant < 1 yr without vagal stimulus or medication. Age HR reference: Neonate 100–180; Infant M 100–160; Toddler/preschool 90–140; School 70–120; Adolescent 60–100.Respiratory Rate Abnormality (Age-Adjusted)RR > 2 SD above normal for age OR mechanical ventilation for acute illness (not neurological/anesthesia). Normal RR reference: Neonate 30–50; Infant 25–40; Preschool 20–30; School 18–25; Adolescent 12–20.WBC Count AbnormalityWBC above age-normal range OR < 4,000 cells/mm³ OR > 10% bands (immature neutrophils)

Infection — Required for Sepsis Diagnosis (in Addition to ≥ 2 SIRS Criteria)major

Suspected or Confirmed Infection (Any Source)Clinical suspicion of infection based on history, exam, lab findings. Culture not required — suspected infection is sufficient for sepsis classification.

Organ Dysfunction Criteria (Required for Severe Sepsis)minor

Cardiovascular DysfunctionHypotension (SBP < 5th percentile for age) OR vasopressor need despite 40 mL/kg IV fluid bolusRespiratory DysfunctionPaO₂/FiO₂ < 300, or new O₂ requirement to maintain SpO₂ > 92%, or invasive/non-invasive ventilation requiredRenal DysfunctionSerum creatinine ≥ 2× upper limit of normal for age OR 50% rise in creatinine above baselineHepatic DysfunctionTotal bilirubin ≥ 4 mg/dL (> 68 μmol/L) in infants > 1 month, or ALT/AST > 2× upper limit of normal for ageHematologic DysfunctionPlatelet count < 80,000/μL OR acute decrease of 50% from highest value in previous 3 days (in thrombocytopenia-prone patient); PT/aPTT > upper limit of normal for ageCNS DysfunctionGlasgow Coma Scale (GCS) ≤ 11 (or acute change ≥ 3 in GCS from abnormal baseline)

Septic Shock Criteria (Sepsis + Cardiovascular Dysfunction Refractory to Fluids)major

Refractory Hypotension or Vasopressor RequirementSBP < 5th percentile for age OR vasopressor requirement to maintain BP despite adequate fluid resuscitation (≥ 40 mL/kg isotonic crystalloid)

Pediatric SIRS and Sepsis Criteria (IPSCC 2005)

Pediatric SIRS and Sepsis Criteria (IPSCC 2005)