Systemic Immune-Inflammation Index (SII)
Immunity & allergy markersWhat the test generally measures, and what to ask about it.
Longetic keeps every lab and record you’ve had organized and easy to find, so your own Systemic Immune-Inflammation Index (SII) values sit together on one chart and you walk into your next appointment prepared.
What is Systemic Immune-Inflammation Index (SII)?
A calculated index combining platelets, neutrophils, and lymphocytes into a single marker of systemic inflammation.
SII is a calculated value from a routine CBC: it multiplies your platelet count by your neutrophil count and divides by your lymphocyte count - (platelets times neutrophils) divided by lymphocytes. A higher SII can be associated with a stronger systemic inflammatory state and, in research, less favorable outcomes, a lower value can be associated with a calmer immune profile. It is a general signal, not a diagnosis.
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References
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