E21.0

Primary hyperparathyroidism

Billable FY2026 2025-10-01 → 2026-09-30

Exclusions 8 never code together

E21code

Excludes1

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

Excludes2

familial hypocalciuric hypercalcemia (E83.52)E83.52

E20-E35block

Excludes1

galactorrhea (N64.3)N64.3
gynecomastia (N62)N62

E00-E89chapter

Excludes1

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

Excludes1 — never code together. The excluded condition and this one are mutually exclusive.

Excludes2 — not included here, but the patient may have both. Code both when documented.

Instructional notes 3

E21.0code

Inclusion terms

Hyperplasia of parathyroid
Osteitis fibrosa cystica generalisata [von Recklinghausen's disease of bone]

E00-E89chapter

Notes

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.E05.8 E07.0 E16-E31 E34.-

Index entries leading here 9

Recklinghausen disease Q85.01
- bones E21.0
Von Recklinghausen
- disease (neurofibromatosis) Q85.01
  - bones E21.0
Curvature
- spine (acquired) (angular) (idiopathic) (incorrect) (postural) — see Dorsopathy, deforming
  - due to or associated with
    - osteitis
      - fibrosa cystica E21.0
Osteitis — see also Osteomyelitis
- fibrosa NEC — see Cyst, bone, by site
  - cystica (generalisata) E21.0
  - osteoplastica E21.0
- parathyroid E21.0
Disease, diseased — see also Syndrome
- osteofibrocystic E21.0
Enlargement, enlarged — see also Hypertrophy
- parathyroid (gland) E21.0
Hyperparathyroidism E21.3
- primary E21.0
Hyperplasia, hyperplastic
- parathyroid (gland) E21.0
Hypertrophy, hypertrophic
- parathyroid (gland) E21.0

Alongside this code 5 same parent — E21

E21.1 Secondary hyperparathyroidism, not elsewhere classified E21.2 Other hyperparathyroidism E21.3 Hyperparathyroidism, unspecified E21.4 Other specified disorders of parathyroid gland E21.5 Disorder of parathyroid gland, unspecified

Medications 1

2 Hyperparathyroidism, Primary drugs

MED-RT files conditions by MeSH, which carves the world differently from ICD-10. These are name matches on this code's description, offered as candidates — not as an assertion that they are this code.

Additional references

AHA Coding Clinic® Licence required

Official coding advice for this code. Published by the American Hospital Association. Not included in this installation.

Risk adjustment

CMS22HCC23 ESRD21HCC23 ESRD24HCC23 RX08HCC43

Presence is a property of the code. Untick a model to hide it everywhere.

This code

Billable: yes
Code set: FY2026
Parent: E21
Block: E20-E35
Siblings: 5

Present FY2024–FY2027.