Z79.621 — Long term (current) use of calcineurin inhibitor
ICD-10-CM
Prior Authorization
No Prior Auth Required
Code is covered without prior authorization (high confidence)
Documentation Required
- The medical record must clearly document the necessity for the vitamin D test(s), including the clinical indication, and must document any repeat testing and the frequency of repeat testing.
- Medical records relating to the test must be made available to Medicare upon request.
- Providers must follow Correct Coding Initiative (CCI) guidance for correct HCPCS/CPT coding and appropriate code combinations prior to billing Medicare; documentation must support the CPT/HCPCS codes billed.
- Medical record documentation must justify the specific vitamin D assay chosen for the patient's disease entity.
Key Coverage Criteria
- Vitamin D assay testing is covered when the medical record documents medical necessity for the test, including the clinical reason for testing and any planned repeat testing and frequency.
- Measurement of 25‑OH Vitamin D is indicated for patients with chronic kidney disease stage III or greater.
- Measurement of 25‑OH Vitamin D is indicated for patients with cirrhosis.
- Measurement of 25‑OH Vitamin D is indicated for patients with hypocalcemia.
- Measurement of 25‑OH Vitamin D is indicated for patients with hypercalcemia.
- Measurement of 25‑OH Vitamin D is indicated for patients with hypercalciuria.
2 Active Policies
A57718 — Billing and Coding: Vitamin D Assay Testing
L36692 — Vitamin D Assay Testing
Related Codes
Have a follow-up question?
Ask Verity about documentation requirements, denial risks, or coverage in your state.