82728

Ferritin Assay

CPT code 82728 refers to a diagnostic laboratory test used to quantify the level of ferritin in a patient's serum or plasma. Ferritin is a high-molecular-weight protein, primarily found inside cells, that serves as the major reservoir for iron storage within the body. While the vast majority of ferritin is located intracellularly within the liver, spleen, and bone marrow, a small but proportional amount circulates in the blood, making it an excellent and non-invasive biomarker for total body iron stores. A ferritin test is clinically vital for distinguishing between iron-deficiency anemia and anemia of chronic disease. In cases of iron deficiency, ferritin levels are typically the first to drop, often well before changes in hemoglobin levels or red blood cell morphology occur, making it a highly sensitive indicator of early-stage iron depletion. Conversely, significantly elevated ferritin levels can indicate iron overload conditions such as hereditary hemochromatosis or complications from frequent blood transfusions. However, clinicians must interpret elevated ferritin results with caution because the protein also functions as an acute-phase reactant. This means that ferritin levels can rise significantly during periods of systemic inflammation, acute infection, chronic kidney disease, malignancy, or liver damage, regardless of the patient's actual iron stores. The laboratory assay is typically performed using an automated immunoassay platform employing techniques such as enzyme-linked immunosorbent assay (ELISA) or chemiluminescent immunoassay (CLIA). By measuring the concentration of ferritin, healthcare providers can monitor the efficacy of iron supplementation therapy, evaluate patients presenting with chronic fatigue or unexplained anemia, and screen for various metabolic disorders involving iron homeostasis.

Clinical Indications

  • Diagnosis of iron deficiency anemia
  • Screening for hereditary hemochromatosis or iron overload
  • Monitoring iron stores in patients with chronic kidney disease (CKD)
  • Evaluation of microcytic anemia
  • Assessment of iron status in pregnant women
  • Differential diagnosis of anemia of chronic disease
  • Monitoring response to iron replacement therapy
  • Investigation of unexplained chronic fatigue

Procedure Steps

  1. Perform a standard venipuncture to obtain a peripheral venous blood sample.
  2. Collect the specimen in a serum separator tube (SST) or a heparinized plasma tube.
  3. Allow the blood to clot (if using SST) and centrifuge the specimen to separate the serum or plasma from cellular components.
  4. Ensure the sample is not hemolyzed, as this may interfere with results.
  5. Transfer the serum or plasma specimen to the laboratory analyzer.
  6. Utilize a quantitative immunoassay method, such as ELISA or chemiluminescence, to measure the ferritin concentration.
  7. Standardize the measurements against known control concentrations of ferritin.
  8. Validate the results and report the numerical value, typically in ng/mL or μg/L.

Coding Guidelines

  • CPT 82728 represents a quantitative assay and should be reported for each separate clinical session.
  • Do not bundle 82728 with iron (83540) or TIBC (83550); these are distinct tests and should be coded separately unless a specific panel code applies.
  • Ensure the diagnosis code (ICD-10-CM) accurately reflects the medical necessity for the test to avoid denials under NCD/LCD guidelines.
  • If the assay is performed on a source other than serum or plasma, documentation must support the source; however, 82728 is primarily for blood-based testing.
  • Check for payer-specific rules regarding the frequency of testing for chronic conditions like ESRD.

Associated ICD-10 Codes