2020 ICD-10-CM Diagnosis Code E21.0

Primary hyperparathyroidism

    2016 2017 2018 2019 2020 Billable/Specific Code
  • E21.0 is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes.
  • The 2020 edition of ICD-10-CM E21.0 became effective on October 1, 2019.
  • This is the American ICD-10-CM version of E21.0 - other international versions of ICD-10 E21.0 may differ.
Applicable To
  • Hyperplasia of parathyroid
  • Osteitis fibrosa cystica generalisata [von Recklinghausen's disease of bone]
The following code(s) above E21.0 contain annotation back-references
Annotation Back-References
In this context, annotation back-references refer to codes that contain:
  • Applicable To annotations, or
  • Code Also annotations, or
  • Code First annotations, or
  • Excludes1 annotations, or
  • Excludes2 annotations, or
  • Includes annotations, or
  • Note annotations, or
  • Use Additional annotations
that may be applicable to E21.0:
  • E00-E89
    2020 ICD-10-CM Range E00-E89

    Endocrine, nutritional and metabolic diseases

    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.
    Type 1 Excludes
    • transitory endocrine and metabolic disorders specific to newborn (P70-P74)
    Endocrine, nutritional and metabolic diseases
  • E20-E35
    2020 ICD-10-CM Range E20-E35

    Disorders of other endocrine glands

    Type 1 Excludes
    Disorders of other endocrine glands
  • E21
    ICD-10-CM Diagnosis Code E21

    Hyperparathyroidism and other disorders of parathyroid gland

      2016 2017 2018 2019 2020 Non-Billable/Non-Specific Code
    Type 1 Excludes
    • adult osteomalacia (M83.-)
    • ectopic hyperparathyroidism (E34.2)
    • familial hypocalciuric hypercalcemia (E83.52)
    • hungry bone syndrome (E83.81)
    • infantile and juvenile osteomalacia (E55.0)
    Hyperparathyroidism and other disorders of parathyroid gland
Approximate Synonyms
  • Hyperparathyroidism, primary
  • Parathyroid hyperplasia
Clinical Information
  • A condition of abnormally elevated output of parathyroid hormone due to parathyroid hyperplasia or parathyroid neoplasms. It is characterized by the combination of hypercalcemia, phosphaturia, elevated renal 1,25-dihydroxyvitamin d3 synthesis, and increased bone resorption.
  • Abnormal increase in the number of otherwise normal cells in the parathyroid gland without tumor formation that leading to enlargement of the gland; it differs from hypertrophy, which is an increase in bulk without an increase in the number of cells.
  • Hyperfunction of the parathyroid glands resulting in the overproduction of parathyroid hormone. It is caused by parathyroid adenoma, parathyroid hyperplasia, parathyroid carcinoma, and multiple endocrine neoplasia. It is associated with hypercalcemia and hypophosphatemia. Signs and symptoms include weakness, fatigue, nausea, vomiting, constipation, depression, bone pain, osteoporosis, cystic bone lesions, and kidney stones.
ICD-10-CM E21.0 is grouped within Diagnostic Related Group(s) (MS-DRG v37.0):
  • 643 Endocrine disorders with mcc
  • 644 Endocrine disorders with cc
  • 645 Endocrine disorders without cc/mcc

Convert E21.0 to ICD-9-CM

Code History
  • 2016 (effective 10/1/2015): New code (first year of non-draft ICD-10-CM)
  • 2017 (effective 10/1/2016): No change
  • 2018 (effective 10/1/2017): No change
  • 2019 (effective 10/1/2018): No change
  • 2020 (effective 10/1/2019): No change
Code annotations containing back-references to E21.0:
  • Code First: G73.7
    , M49
    ICD-10-CM Diagnosis Code G73.7

    Myopathy in diseases classified elsewhere

      2016 2017 2018 2019 2020 Billable/Specific Code Manifestation Code
    Code First
    • underlying disease, such as:
    • hyperparathyroidism (E21.0, E21.3)
    • hypoparathyroidism (E20.-)
    • glycogen storage disease (E74.0)
    • lipid storage disorders (E75.-)
    Type 1 Excludes
    • myopathy in:
    • rheumatoid arthritis (M05.32)
    • sarcoidosis (D86.87)
    • scleroderma (M34.82)
    • sicca syndrome [Sjögren] (M35.03)
    • systemic lupus erythematosus (M32.19)
    ICD-10-CM Diagnosis Code M49

    Spondylopathies in diseases classified elsewhere

      2016 2017 2018 2019 2020 Non-Billable/Non-Specific Code
    Code First
    • underlying disease, such as:
    • brucellosis (A23.-)
    • Charcot-Marie-Tooth disease (G60.0)
    • enterobacterial infections (A01-A04)
    • osteitis fibrosa cystica (E21.0)
    Includes
    • curvature of spine in diseases classified elsewhere
    • deformity of spine in diseases classified elsewhere
    • kyphosis in diseases classified elsewhere
    • scoliosis in diseases classified elsewhere
    • spondylopathy in diseases classified elsewhere
    Type 1 Excludes
    • curvature of spine in tuberculosis [Pott's] (A18.01)
    • enteropathic arthropathies (M07.-)
    • gonococcal spondylitis (A54.41)
    • neuropathic [tabes dorsalis] spondylitis (A52.11)
    • neuropathic spondylopathy in syringomyelia (G95.0)
    • neuropathic spondylopathy in tabes dorsalis (A52.11)
    • nonsyphilitic neuropathic spondylopathy NEC (G98.0)
    • spondylitis in syphilis (acquired) (A52.77)
    • tuberculous spondylitis (A18.01)
    • typhoid fever spondylitis (A01.05)
  • Type 1 Excludes: M85.6
    , E83.5
    ICD-10-CM Diagnosis Code M85.6

    Other cyst of bone

      2016 2017 2018 2019 2020 Non-Billable/Non-Specific Code
    Type 1 Excludes
    • cyst of jaw NEC (M27.4)
    • osteitis fibrosa cystica generalisata [von Recklinghausen's disease of bone] (E21.0)
    ICD-10-CM Diagnosis Code E83.5

    Disorders of calcium metabolism

      2016 2017 2018 2019 2020 Non-Billable/Non-Specific Code
    Type 1 Excludes

Diagnosis Index entries containing back-references to E21.0:

ICD-10-CM Codes Adjacent To E21.0
E16.3 Increased secretion of glucagon
E16.4 Increased secretion of gastrin
E16.8 Other specified disorders of pancreatic internal secretion
E16.9 Disorder of pancreatic internal secretion, unspecified
E20 Hypoparathyroidism
E20.0 Idiopathic hypoparathyroidism
E20.1 Pseudohypoparathyroidism
E20.8 Other hypoparathyroidism
E20.9 Hypoparathyroidism, unspecified
E21 Hyperparathyroidism and other disorders of parathyroid gland
E21.0 Primary hyperparathyroidism
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
E22 Hyperfunction of pituitary gland
E22.0 Acromegaly and pituitary gigantism
E22.1 Hyperprolactinemia
E22.2 Syndrome of inappropriate secretion of antidiuretic hormone
E22.8 Other hyperfunction of pituitary gland

Reimbursement claims with a date of service on or after October 1, 2015 require the use of ICD-10-CM codes.