2026 ICD-10-CM Diagnosis Code E80.21Acute intermittent (hepatic) porphyria

ICD-10-CM Codes›E00–E89›E70-E88›E80

ICD-10-CM E80.21
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

E80.21 is a billable ICD-10-CM diagnosis code for acute intermittent (hepatic) porphyria. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026). Coders also document this condition as acute intermittent porphyria. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified and unspecified nutritional and metabolic disorders.

Code Identity

ICD-10-CM Code
E80.21
Billable Status
Yes — Valid for Submission
Code Describes
Acute intermittent (hepatic) porphyria
Short Description
Acute intermittent (hepatic) porphyria
Same as the full description in the CMS dataset.
Parent Code
E80.2
Other and unspecified porphyria

Code Classification

ChapterE00–E89Endocrine, nutritional and metabolic diseases
SectionE70-E88Metabolic disorders
CategoryE80Disorders of porphyrin and bilirubin metabolism
This CodeE80.21Acute intermittent (hepatic) porphyria

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acute intermittent porphyria
  • Homozygous acute intermittent porphyria
  • Porphobilinogen deaminase deficiency

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Porphyria(South African)
      • acute intermittent (hepatic) (Swedish)

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR END016
Other specified and unspecified nutritional and metabolic disorders
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Porphyria

Porphyrias are a group of genetic disorders caused by problems with how your body makes a substance called heme. Heme is found throughout the body, especially in your blood and bone marrow, where it carries oxygen.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert E80.21 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
277.1 Dis porphyrin metabolism
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About E80.21Overview

Is E80.21 (Other and unspecified porphyria) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report acute intermittent (hepatic) porphyria on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What is the ICD-9 equivalent of E80.21?

Under the General Equivalence Mappings, acute intermittent (hepatic) porphyria converts to ICD-9-CM 277.1 (dis porphyrin metabolism). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.