ICD-10-CM code · FY2027

E21.1 Secondary hyperparathyroidism, not elsewhere classified

BillableValid for claims as a specific diagnosis code

About E21.1

Code
E21.1
Billable
Yes
Short description
Secondary hyperparathyroidism, not elsewhere classified
Category
E21 Hyperparathyroidism and other disorders of parathyroid gland
Block
E20-E35 Disorders of other endocrine glands
Chapter
4 Endocrine, nutritional and metabolic diseases
Code set
FY2027, October 1, 2026 to September 30, 2027
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Coding notes for E21.1

Excludes1 Not coded here: never report these together with this code (use the code given instead).

  • secondary hyperparathyroidism of renal origin (N25.81)

Also applies, from E21 Hyperparathyroidism and other disorders of parathyroid gland

Excludes1 Not coded here: never report these together with this code (use the code given instead).

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

Excludes2 Not part of this condition, but a patient can have both: report both codes when both apply.

  • familial hypocalciuric hypercalcemia (E83.52)
Block E20-E35 notes (apply to every code in it)

Excludes1 Not coded here: never report these together with this code (use the code given instead).

Chapter 4 notes (apply to every code in it)

Note

  • All neoplasms, whether functionally active or not, are classified in Chapter 2. Appropriate codes in this chapter (i.e. E05.8, E07.0, E16-E31, E34.-) may be used as additional codes to indicate either functional activity by neoplasms and ectopic endocrine tissue or hyperfunction and hypofunction of endocrine glands associated with neoplasms and other conditions classified elsewhere.

Excludes1 Not coded here: never report these together with this code (use the code given instead).

  • transitory endocrine and metabolic disorders specific to newborn (P70-P74)

Related codes in E21

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ICD-10-CM FY2027 code set, as published by the CDC National Center for Health Statistics (NCHS) and CMS, effective October 1, 2026 to September 30, 2027. Codes, titles and notes are shown as published. Check payer rules and the official guidelines before billing. This page is not medical advice.