ICD-10-CM 2026 · Effective October 1, 2025

ICD-10 E21

Non-Billable Header

Hyperparathyroidism and other disorders of parathyroid gland

E21
Block
0
Synonyms
0
LCDs
3
Payer Policies
0
Linked CPTs

About ICD-10-CM E21

ICD-10-CM code E21 represents Hyperparathyroidism and other disorders of parathyroid gland. This is a non-billable header code in the Endocrine, Nutritional, and Metabolic chapter (block E21). The 2026 edition of ICD-10-CM E21 became effective on October 1, 2025. Non-billable codes cannot be used as a primary or secondary diagnosis on a claim, use a more specific child code instead.

Type 1 Excludes

Pure excludes, these codes can never be coded together with E21. The conditions are mutually exclusive (e.g., congenital vs acquired forms).

  • adult osteomalacia (M83.-)
  • ectopic hyperparathyroidism (E34.2)
  • hungry bone syndrome (E83.81)
  • infantile and juvenile osteomalacia (E55.0)

Type 2 Excludes

Not included here, the excluded code is not part of E21, but a patient may have both conditions at the same time. Both codes may be coded together when applicable.

  • familial hypocalciuric hypercalcemia (E83.52)

Medicare LCD Coverage for E21

Local Coverage Determinations (LCDs) from CMS MACs that list E21 as a covered diagnosis.

No Medicare LCDs reference E21 as covered

This doesn't mean the code isn't covered, it means no MAC has issued a Local Coverage Determination naming this specific code. Coverage may still apply under National Coverage Determinations or general medical-necessity rules.

Commercial Payer Coverage

Coverage policies from major commercial payers referencing E21.

3 policies

3 Cigna

Duplex Scan of Extracranial Arteries - (0542)
Policy ID: MM_0542
Occupational Therapy - (CPG155)
Policy ID: CPG155_OCCUPATIONAL_THERAPY
Physical Therapy - (CPG135)
Policy ID: CPG135_PHYSICAL_THERAPY

CPT Codes Commonly Billed with E21

Procedures frequently paired with this diagnosis based on PayerReady's Dx↔Px linkage data.

No procedure linkages on file for E21

We don't have CPT pairings indexed for this specific code yet. Use the CPT search above to find common procedures, or check your payer's published medical policy for code-specific guidance.

ICD-10 E21, Billing FAQ

Is ICD-10 code E21 billable? +

No, E21 is a non-billable header code. Use a more specific child code from block E21 when submitting claims.

What codes are Type 1 Excludes for E21? +

Type 1 Excludes (never code together with E21): adult osteomalacia (M83.-); ectopic hyperparathyroidism (E34.2); hungry bone syndrome (E83.81)

What codes are Type 2 Excludes for E21? +

Type 2 Excludes (may be coded together when both conditions exist): familial hypocalciuric hypercalcemia (E83.52)

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Reviewed by the PayerReady Medical Coding Team

Verified against the CMS 2026 code set on May 31, 2026.

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