Multicenter Symphony IL-6 Monitoring Sepsis ICU Validation Study

Inclusion Criteria: * Adult patients (≥22 years of age) * Diagnosis of sepsis or septic shock based on: the Third International Consensus Definitions (Sepsis-3 criteria) defined as at least one of the following criteria as determined by a treating physician or study physician investigator. * Sepsis: suspected or documented infection (i.e., use or intent to use antibiotics as an indicator) and organ dysfunction defined by a Sequential Organ Failure Assessment (SOFA) score ≥2 * Septic shock: sepsis requiring vasopressors and serum lactate levels \>2 mmol/L (18 mg/dL) * Admitted or intended to be admitted to the ICU * At least 3 mL plasma drawn and available for collection (or is anticipated to be able to be drawn and available) within 24 hours of (i.e., up to 24 hours after) the earliest diagnosis of sepsis or septic shock. Exclusion Criteria: * Prisoners or imprisonment at time of enrollment * Prior enrollment into this study * Informed consent as approved by IRB is unable to be obtained.