Systemic inflammation response index (SIRI)
Immune system healthAlso known as: inflammation response index, Entzündungsindex, systemischer Entzündungsindex
SIRI combines neutrophils, monocytes, and lymphocytes to evaluate immune response and inflammation severity.
Reference range
Source: Ahead Health benchmark
Reference ranges may vary between labs and assays. Always interpret results with your healthcare provider.
Why this matters
SIRI captures both acute and chronic inflammatory components, making it sensitive to a broader range of inflammatory conditions than NLR alone. The inclusion of monocytes adds information about tissue macrophage activity and chronic inflammatory states. Elevated SIRI predicts mortality in cancer, sepsis, and heart failure, often outperforming other inflammatory indices. It's particularly useful for detecting smoldering inflammation in metabolic syndrome, atherosclerosis, and autoimmune diseases.
How this connects to other biomarkers
- SIRI (Neutrophils (abs.) × Monocytes (abs.) / Lymphocytes (abs.)) emphasizes the activation of innate immunity (neutrophils, monocytes) versus adaptive immunity (lymphocytes).
- Elevated SIRI is associated with worse outcomes in atherosclerosis, cancer prognosis, and stroke recovery.
- Interpret alongside NLR (Neutrophils/Lymphocytes) and Systemic Immune-Inflammation Index (SII) for a comprehensive systemic-inflammation profile.
How often should I test Systemic inflammation response index (SIRI)?
Most adults benefit from yearly SIRI reassessment as part of a CBC with differential.
At baseline / for screening: Once every 12 months from age 30 as part of a CBC with differential. More frequently if you have a chronic inflammatory condition.
When monitoring an intervention or change: These ratios are tracked alongside the CBC rather than on their own cadence. Retest with your next CBC after a sustained anti-inflammatory lifestyle change (better sleep, weight loss, Mediterranean-style diet). Single values are sensitive to acute illness, recent exercise, and stress, so test under consistent conditions.
Included in
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