E21 ICD-10-CM Code: Hyperparathyroidism and other disorders of parathyroid gland
A clear reference for the official code description, hierarchy, and related coding information from the FY 2027 U.S. release.
Official description
E21Hyperparathyroidism and other disorders of parathyroid gland
ICD-10-CM diagnosis code · United States clinical modification
Where E21 sits
- 1
Chapter 4
Endocrine, nutritional and metabolic diseases (E00-E89)
- 2
Section
Disorders of other endocrine glands (E20-E35)
- 3
Category E21
Hyperparathyroidism and other disorders of parathyroid gland
- 4
Code E21
Hyperparathyroidism and other disorders of parathyroid gland
Codes under E21
E21 is a non-billable category. Choose the child code that best matches the documented diagnosis.
Notes for this code
Inclusion terms
No inclusion terms are listed for E21.
Code first
No “code first” instruction is listed for E21.
Use additional code
No “use additional code” instruction is listed for E21.
Excludes1
Conditions that should not be reported together with this code.
- adult osteomalacia (M83.-)
- ectopic hyperparathyroidism (E34.2)
- hungry bone syndrome (E83.81)
- infantile and juvenile osteomalacia (E55.0)
Excludes2
Conditions not included here that may be reported separately when present.
- familial hypocalciuric hypercalcemia (E83.52)
Source and release
- Data release
- U.S. ICD-10-CM · FY 2027
- Effective date
- Oct 1, 2026
- Publisher
- Vero Scribe Inc.
This reference is generated from Vero’s ICD-10-CM description, hierarchy, and code-note dataset. The visible content and structured data share that source.
Frequently asked questions
What does ICD-10-CM code E21 mean?
E21 is the FY 2027 U.S. ICD-10-CM code for “Hyperparathyroidism and other disorders of parathyroid gland.”
Is E21 a billable or specific ICD-10-CM code?
No. E21 has more specific child codes in the FY 2027 reference data. Select the code that matches the documentation and confirm the active code set and payer requirements.
Where is E21 located in ICD-10-CM?
E21 is listed in Chapter 4, Endocrine, nutritional and metabolic diseases (E00-E89), within Disorders of other endocrine glands (E20-E35) (E20–E35), under category E21, Hyperparathyroidism and other disorders of parathyroid gland.
What coding notes are listed for E21?
No inclusion terms are listed for E21 in this reference record. No code-first instruction is listed. Excludes1 notes: adult osteomalacia (M83.-); ectopic hyperparathyroidism (E34.2); hungry bone syndrome (E83.81); infantile and juvenile osteomalacia (E55.0). Excludes2 notes: familial hypocalciuric hypercalcemia (E83.52).