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E21.2

E21.2Other hyperparathyroidism

Billable / specific codeICD-10-CM

E21.2 is a billable, specific ICD-10-CM code for other hyperparathyroidism. It is valid for submission on a claim.

Excludes2 — not included here, but may coexist

The excluded condition is not part of this code, but a patient can have both. You may code both.

  • familial hypocalciuric hypercalcemia (E83.52)

Inclusion terms

Alternative wordings a physician may use in the chart for this same code.

  • Tertiary hyperparathyroidism

Risk adjustment

E21.2 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

Medicare coverage

E21.2 is named in 13 Medicare coverage policies 13 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.

  • A56416Billing and Coding: Assays for Vitamins and Metabolic Function
  • A56798Billing and Coding: Vitamin D Assay Testing
  • A56841Billing and Coding: Vitamin D; 25 hydroxy, includes fraction(s), if performed
  • A57122Billing and Coding: Parathormone (Parathyroid Hormone)

How E21.2 is indexed

Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to E21.2.

  • Hyperparathyroidismspecified NEC
  • Hyperparathyroidismtertiary

Related codes at this level

Codes that share E21. If E21.2 is not quite right, the correct code is usually one of these.

Questions about E21.2

Is E21.2 a billable ICD-10-CM code?
Yes. E21.2 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does E21.2 sit in the tabular list?
Endocrine, nutritional and metabolic diseases (E00-E89), in the block Disorders of other endocrine glands (E20-E35).
ICD-10-CMFY2026-Apr· effective April 1, 2026

Loaded directly from the CMS/NCHS ICD-10-CM public-domain release — see data sources and our editorial policy. If this page disagrees with the CMS tabular list, this page is wrong. Reference information for professional coders; not medical or billing advice.