REFERENCE LABORATORY CHANGE
Interleukin 18
Order Code: CIL18
Fee Code AA748 (CPT 83520)
Reference Laboratory: Cincinnati Children’s Hospital #7453047
New Order Code: VIL18
New Reference Lab: Viracor #33611
Requests for Interleukin 18 will be sent to Eurofins Viracor effective August 27, 2026.
Interleukin-18 (IL-18) (also known as Interferon-gamma Inducing Factor) is a pro-inflammatory cytokine and member of the IL-1 superfamily that serves as a potent inducer of IFN-γ production from T cells and NK cells, bridging innate and adaptive immune responses. IL-18 is constitutively expressed as an inactive precursor in nearly all cell types, and its activation and secretion is regulated through inflammasome processing. Free IL-18 (not bound by its endogenous inhibitor, IL-18 binding protein/IL-18BP) represents the biologically active form.
Collection Instructions: Collect specimen in a lavender top (EDTA) tube. Centrifuge within 2 hours of collection, aliquot 1 mL of plasma into a screw capped plastic vial, and freeze.
Reference Range: <245 pg/mL