E21 vs E34.2
E21 (Hyperparathyroidism and other disorders of parathyroid gland) compared with E34.2 (Ectopic hormone secretion, not elsewhere classified), from the official CMS tabular data. Do not report these codes together: the official tabular list marks them Excludes1.
Can these codes be reported together?
No — do not report together. E21 carries an Excludes1 note covering E34.2: “ectopic hyperparathyroidism (E34.2)”
Sole exception: when the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).
Side by side
| E21Hyperparathyroidism and other disorders of parathyroid gland | E34.2Ectopic hormone secretion, not elsewhere classified | |
|---|---|---|
| Billing status | Non-billable header | Billable |
| Classification | E00-E89 — Endocrine, Nutritional and Metabolic Diseases (E00-E89) | E00-E89 — Endocrine, Nutritional and Metabolic Diseases (E00-E89) |
| Definition | Hyperparathyroidism and other disorders of parathyroid gland is a non-billable ICD-10-CM category code (E21). | Ectopic hormone secretion, not elsewhere classified is a billable ICD-10-CM diagnosis code (E34.2). |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources