2024 ICD-10-CM Diagnosis Code E21.2

Other hyperparathyroidism

ICD-10-CM Code:
ICD-10 Code for:
Other hyperparathyroidism
Is Billable?
Yes - Valid for Submission
Chronic Condition Indicator: [1]
Code Navigator:

Code Classification

  • Endocrine, nutritional and metabolic diseases
    • Disorders of other endocrine glands
      • Hyperparathyroidism and other disorders of parathyroid gland

E21.2 is a billable diagnosis code used to specify a medical diagnosis of other hyperparathyroidism. The code is valid during the current fiscal year for the submission of HIPAA-covered transactions from October 01, 2023 through September 30, 2024.

Approximate Synonyms

The following clinical terms are approximate synonyms or lay terms that might be used to identify the correct diagnosis code:

  • Aberrant parathyroid gland
  • Congenital anomaly of parathyroid glands
  • Ectopic hyperparathyroidism
  • Ectopic parathyroid hormone-related protein secretion
  • Tertiary hyperparathyroidism

Clinical Classification

Clinical Information

  • Hyperparathyroidism

    a condition of abnormally elevated output of parathyroid hormone (or pth) triggering responses that increase blood calcium. it is characterized by hypercalcemia and bone resorption, eventually leading to bone diseases. primary hyperparathyroidism is caused by parathyroid hyperplasia or parathyroid neoplasms. secondary hyperparathyroidism is increased pth secretion in response to hypocalcemia, usually caused by chronic kidney diseases.
  • Hyperparathyroidism, Primary

    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.
  • Hyperparathyroidism, Secondary

    abnormally elevated parathyroid hormone secretion as a response to hypocalcemia. it is caused by chronic kidney failure or other abnormalities in the controls of bone and mineral metabolism, leading to various bone diseases, such as renal osteodystrophy.
  • Tertiary Hyperparathyroidism

    an overproduction of parathyroid hormone that is autonomous and often associated with chronic secondary hyperparathyroidism.

Index to Diseases and Injuries References

The following annotation back-references for this diagnosis code are found in the injuries and diseases index. The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10-CM code(s).

Convert E21.2 to ICD-9-CM

  • ICD-9-CM Code: 252.08 - Hyperparathyroidism NEC

Patient Education

Parathyroid Disorders

Most people have four pea-sized glands, called parathyroid glands, on the thyroid gland in the neck. Though their names are similar, the thyroid and parathyroid glands are completely different. The parathyroid glands make parathyroid hormone (PTH), which helps your body keep the right balance of calcium and phosphorous.

If your parathyroid glands make too much or too little hormone, it disrupts this balance. If they secrete extra PTH, you have hyperparathyroidism, and your blood calcium rises. In many cases, a benign tumor on a parathyroid gland makes it overactive. Or, the extra hormones can come from enlarged parathyroid glands. Very rarely, the cause is cancer.

If you do not have enough PTH, you have hypoparathyroidism. Your blood will have too little calcium and too much phosphorous. Causes include injury to the glands, endocrine disorders, or genetic conditions. Treatment is aimed at restoring the balance of calcium and phosphorous.

NIH: National Institute of Diabetes and Digestive and Kidney Diseases

[Learn More in MedlinePlus]

Code History

  • FY 2024 - No Change, effective from 10/1/2023 through 9/30/2024
  • FY 2023 - No Change, effective from 10/1/2022 through 9/30/2023
  • FY 2022 - No Change, effective from 10/1/2021 through 9/30/2022
  • FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016. This was the first year ICD-10-CM was implemented into the HIPAA code set.


[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.