CPT® Code 82331

A laboratory test identified by CPT® Code 82331 is conducted to measure calcium blood levels following a calcium infusion test. Calcium is a vital mineral that plays a crucial role in various physiological functions, including maintaining bone health, facilitating heart function, enabling muscle contraction, supporting nerve signaling, and aiding in blood clotting. While the majority of the body's calcium is stored in the bones, only a small fraction, approximately 1%, is present in the bloodstream. Of this circulating calcium, about half is metabolically active, while the remainder is either bound to albumin or complexed with phosphate. The calcium infusion test is particularly significant in the diagnostic evaluation of conditions such as gastrinoma or insulinoma, where gastrin and insulin levels are monitored before, during, and after the infusion of calcium. Following the infusion, a post-infusion calcium level is measured to assess the patient for potential hypo- or hypercalcemia, which are conditions characterized by low or high calcium levels, respectively. The blood sample required for this test is obtained through a venipuncture, which is a separately reportable procedure. The analysis of the serum and/or plasma is performed using quantitative spectrophotometry, a method that allows for precise measurement of calcium concentrations in the blood.