E21.1
Billable codeSecondary hyperparathyroidism, not elsewhere classified
The ICD-10 code for secondary hyperparathyroidism, not elsewhere classified is E21.1.
Clinical notes
Excludes1 (not coded here)
An Excludes1 note is a pure exclusion: the excluded condition and this code should never be reported together, because the two conditions cannot occur at the same time (e.g. a congenital form vs. an acquired form of the same disease).
- secondary hyperparathyroidism of renal origin (N25.81)
Documentation support
General coding-documentation guidance — not a substitute for payer-specific requirements or professional coding judgment.
- •Confirm the excluded condition(s) listed above are not also present — Excludes1 conditions cannot be coded together with this one.
- •As a general rule, code to the highest level of specificity supported by the documentation in the medical record.
Related codes in this category
- E21.0Primary hyperparathyroidism
- E21.2Other hyperparathyroidism
- E21.3Hyperparathyroidism, unspecified
- E21.4Other specified disorders of parathyroid gland
- E21.5Disorder of parathyroid gland, unspecified
- E21.1Secondary hyperparathyroidism, not elsewhere classified
ICD-9-CM equivalent
Informational only — GEM mappings are approximate, not guaranteed one-to-one equivalents. Verify before use in billing.
- 25202
Associated MS-DRGs
E21.1 can serve as the principal diagnosis for these Medicare Severity Diagnosis-Related Groups.
Informational only — actual DRG assignment also depends on procedures, complications/comorbidities (CC/MCC), discharge status, and payer-specific rules not reflected here.