CPT® Code 86357

The CPT® Code 86357 refers to the measurement of total natural killer (NK) cell count through a blood test. Natural killer cells are a type of large granular lymphocyte that plays a crucial role in the immune system, particularly in the body's defense against tumors and virally infected cells. This test is essential for assessing the overall function of the immune system, as NK cells are integral to the body's ability to respond to infections and malignancies. The test is often performed alongside other immunological assessments, including tests for B-cells, T-cells, and specific subsets of T-cells, to provide a comprehensive evaluation of immune status. The procedure involves obtaining a blood sample through venipuncture, which is a standard method for collecting blood for laboratory analysis. The analysis of the blood sample is conducted using quantitative flow cytometry, a sophisticated technique that allows for the precise counting and characterization of different cell types within the blood. This detailed assessment is vital for diagnosing and monitoring various health conditions related to immune function.