CPT® Code 82340

The CPT® Code 82340 refers to a laboratory test that quantifies the levels of calcium in a timed urine specimen. Calcium is a vital mineral that plays several critical roles in the body, including maintaining bone health, facilitating heart function, enabling muscle contraction, supporting nerve signaling, and aiding in blood clotting. While the majority of calcium is stored in the bones, a small fraction circulates in the bloodstream, with only about half of that being metabolically active. The remainder is either bound to proteins such as albumin or complexed with phosphate. Under normal circumstances, the body excretes small amounts of calcium through urine. The measurement of urine calcium levels is particularly important when a patient exhibits abnormal serum calcium levels, as elevated urine calcium can assist in the differential diagnosis of conditions such as parathyroid disorders and familial hypocalciuric hypercalcemia (FHH). Additionally, intermittent monitoring of urine calcium levels can be beneficial in guiding the treatment of these disorders. To perform this test, a random, timed, or 24-hour urine sample is collected, which can be obtained through either a voided specimen or catheterization. The analysis of the urine sample is conducted using quantitative spectrophotometry, a method that allows for precise measurement of calcium concentration in the urine.