ICD-10-CM E21.0 is the diagnosis code for Primary hyperparathyroidism. This code falls under the section "Disorders of other endocrine glands" within Chapter 4 — Endocrine, nutritional and metabolic diseases (E00-E89). It is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes. Medical coders and healthcare providers use this code to document and classify diagnoses in electronic health records, insurance claims, and clinical databases.
Understanding where E21.0 sits in the ICD-10-CM classification helps ensure proper coding:
Yes, E21.0 is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes.
E21.0 is the ICD-10-CM diagnosis code for "Primary hyperparathyroidism". It is used by healthcare providers to classify and document this condition in medical records and insurance claims.
The parent code of E21.0 is E21 ("Hyperparathyroidism and other disorders of parathyroid gland"). E21.0 provides a more specific classification within this category.
E21.0 is located in Section E20-E35 — "Disorders of other endocrine glands" within Chapter 4 of the ICD-10-CM Tabular List.
Use E21.0 when the patients documented diagnosis matches "Primary hyperparathyroidism" and the clinical documentation supports this level of specificity. Always verify with the latest ICD-10-CM guidelines and payer requirements.
The ICD-10-CM code for Primary hyperparathyroidism is E21.0.
Yes, E21.0 can be used as a primary diagnosis code since it is billable and specific.
E21.0 is in Chapter 4 of the ICD-10-CM Tabular List.
Yes, E21.0 is a valid ICD-10-CM code for the 2026 fiscal year, subject to official CMS updates.