Billable / Specific Code
ICD-10-CM E21.1 is the diagnosis code for Secondary hyperparathyroidism, not elsewhere classified. 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.
The following conditions should never be coded at the same time as E21.1. They are mutually exclusive:
Understanding where E21.1 sits in the ICD-10-CM classification helps ensure proper coding:
Yes, E21.1 is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes.
E21.1 is the ICD-10-CM diagnosis code for "Secondary hyperparathyroidism, not elsewhere classified". It is used by healthcare providers to classify and document this condition in medical records and insurance claims.
The parent code of E21.1 is E21 ("Hyperparathyroidism and other disorders of parathyroid gland"). E21.1 provides a more specific classification within this category.
E21.1 is located in Section E20-E35 — "Disorders of other endocrine glands" within Chapter 4 of the ICD-10-CM Tabular List.
Use E21.1 when the patients documented diagnosis matches "Secondary hyperparathyroidism, not elsewhere classified" 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 Secondary hyperparathyroidism, not elsewhere classified is E21.1.
Yes, E21.1 can be used as a primary diagnosis code since it is billable and specific.
E21.1 is in Chapter 4 of the ICD-10-CM Tabular List.
Type 1 Excludes for E21.1 include: secondary hyperparathyroidism of renal origin (N25.81).
Yes, E21.1 is a valid ICD-10-CM code for the 2026 fiscal year, subject to official CMS updates.