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ICD-10-CM 2027 diagnosis code

E20.812Autoimmune hypoparathyroidism

✓ Billable / specific

E20.812 is a valid, billable ICD-10-CM code for autoimmune hypoparathyroidism. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.

Code last changed in FY2024 (effective October 1, 2023). Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data

About E20.812

E20.812 is the ICD-10-CM diagnosis code for autoimmune hypoparathyroidism. It belongs to category E20 (hypoparathyroidism), block E20-E35 (disorders of other endocrine glands) and chapter 4 (endocrine, nutritional and metabolic diseases). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

Within E20.81 (hypoparathyroidism due to impaired parathyroid hormone secretion), E20.812 is specifically for autoimmune hypoparathyroidism. Related codes cover autosomal dominant hypocalcemia (E20.810), secondary hypoparathyroidism in diseases classified elsewhere (E20.811), other specified hypoparathyroidism due to impaired parathyroid hormone secretion (E20.818) and unspecified (E20.819).

Code first , if applicable, underlying condition such as: autoimmune polyglandular failure (E31.0) and Schmidt's syndrome (E31.0).

It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.

In MS-DRG v44.0, it is part of the grouping logic for DRG 643 (Endocrine Disorders with MCC, relative weight 1.6139), DRG 644 (Endocrine Disorders with CC, relative weight 1.0044), DRG 645 (Endocrine Disorders without CC/MCC, relative weight 0.7459), DRG 791 (Prematurity with Major Problems, relative weight 4.1075) and DRG 793 (Full Term Neonate with Major Problems, relative weight 4.2195), in MDC 10 (Endocrine, Nutritional and Metabolic Diseases and Disorders) and MDC 15 (Newborns and Other Neonates with Conditions Originating in the Perinatal Period), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.

It was added in FY2024, effective October 1, 2023.

Coding notes

Code firstSequence the underlying condition first
  • , if applicable, underlying condition such as:
  • autoimmune polyglandular failure (E31.0)
  • Schmidt's syndrome (E31.0)

Notes that apply from higher levels

Instructions written at a parent level also apply to E20.812.

› From E20 Hypoparathyroidism
Excludes1
  • Di George's syndrome (D82.1)
  • postprocedural hypoparathyroidism (E89.2)
  • tetany NOS (R29.0)
  • transitory neonatal hypoparathyroidism (P71.4)

Broader instructions also apply from E20-E35 Disorders of other endocrine glands and Chapter 4: Endocrine, nutritional and metabolic diseases.

Alphabetic index entries

1 entries

Terms in the official ICD-10-CM index that lead to E20.812.

Codes whose notes reference E20.812

MS-DRG v44.0 grouping

All DRGs →

Inpatient MS-DRGs this diagnosis can group to, as the principal or a secondary diagnosis, depending on the rest of the claim.

MDC 15 · Newborns and Other Neonates with Conditions Originating in the Perinatal Period

MDC 15 · Newborns and Other Neonates with Conditions Originating in the Perinatal Period

Code history

  1. 2016
  2. 2017
  3. 2018
  4. 2019
  5. 2020
  6. 2021
  7. 2022
  8. 2023
  9. 2024
  10. 2025
  11. 2026
  12. 2027
  • FY2024 (effective 10/1/2023): Added
  • No changes since FY2024.

Common questions about E20.812

Is E20.812 billable?

Yes. E20.812 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).

Can E20.812 be used as a principal diagnosis?

Yes. The Medicare Code Editor doesn't restrict E20.812 as a principal diagnosis.

Is E20.812 a CC or MCC?

No. E20.812 is neither a CC nor an MCC under MS-DRG v44.0.

What DRG does E20.812 group to?

E20.812 is used in the MS-DRG v44.0 logic for MS-DRG 643 (Endocrine Disorders with MCC), MS-DRG 644 (Endocrine Disorders with CC), MS-DRG 645 (Endocrine Disorders without CC/MCC), MS-DRG 791 (Prematurity with Major Problems) and MS-DRG 793 (Full Term Neonate with Major Problems). Which one applies depends on whether it is the principal diagnosis and on the rest of the claim.