Interleukin-6 Test

Inflammatory cytokine biomarker for predicting COVID-19 progression & severity, and also for evaluation of patients with suspected systemic infection, localized infection, and chronic inflammatory disorders.

7,300.00 60 minutes

    Patient preparation

  • No patient preparation needed.

Clinical Information

Interleukin-6 or IL-6 is a member of the cytokine family, with a pivotal role in the activation and regulation of immune response. Cytokines play several important roles, but its significance to the immune system has been given much importance recently: it triggers “inflammatory cascade” wherein a coordinated and sequential immune response is activated.

The Role of IL-6 in COVID-19 Patient Management

Some recent literature discussed the pathogenesis of cytokine release syndrome (CRS) in severe COVID-19 patients. CRS is a systemic inflammatory response that can be caused by infection, some drugs, and other factors, characterized by a sharp increase in pro-inflammatory cytokine level, like IL-6. Interleukin-6 is a key molecule in CRS and is now being tested to monitor its response in COVID patients. It can be used as predictor for a more immediate diagnosis of patients with higher risk of disease deterioration. Given the high levels of cytokines induced by SARS-CoV-2, a timely treatment to reduce lung damage via inflammation is critical to improving recovery rates and reducing mortality.

Other Clinical Applications of IL-6 Test

Evaluation of patients with:

  • Suspected systemic infection
  • Suspected localized infection, specifically prosthetic joint infection
  • Suspected chronic inflammatory disorders, such as rheumatoid arthritis, systemic ankylosing spondylitis, or inflammatory bowel disease

Test Information

Analytical Method
The interleukin-6 (IL-6) cytokine assay employs an in vitro enzyme-linked immunosorbent assay for the quantitative measurement of human IL-6 in serum. This involves a sandwich immunoassay format where captured antibodies are coated in a single spot at the bottom of each well. The assay employs detection antibodies conjugated with chemiluminescent labels.

Elevated concentrations of Interleukin-6: >7 pg/ml may indicate an ongoing inflammatory response, which could be consistent with a systemic infection or chronic inflammatory disease. For COVID-19 diagnosis: serum IL-6 > 32.1 pg/mL is a severity predictor*


    • Interleukin-6 (IL-6) is a non-specific marker associated with inflammatory response and is NOT diagnostic of any specific disease or disease process. Elevated concentrations of IL-6 must be interpreted within the clinical context of the patient.
    • Normal concentrations of IL-6 DO NOT exclude the possibility of an ongoing inflammatory process.
    • Results SHOULD NOT be used as a diagnostic procedure without confirmation from another medically-established diagnostic product or procedure.

Performance Characteristics

  • Sensitivity: The minimum detectable dose of human IL-6 was determined to be at 3 pg/ml.
  • Recovery: 92.63%
  • reproducibility: RSD < 10%
  • Specificity: This assay is specific to IL6 and will NOT detect other major cytokines.

Sample Information and Patient Preparation

  • Specimen Required: 2 mL serum
  • Turn-Around Time: Cut off every Monday 4PM, release by Thursday 12NN
  • Patient Preparation and Collection:
    No patient preparation needed. Collect blood sample into 1 SST tube.
  • Sample Storage:
    Store serum at -20°C until ready for shipping. Serum can be stored at refrigerated temperatures of 2 to 8oC for only 24 hours, after which must be frozen.
    Storage of serum at ambient temperature is NOT acceptable.
  • Test Kit contains:
    1 SST Tube
    1 Plastic transfer pipette
    1 Amber microcentrifuge tube
    1 Sample collection guide