2026 ICD-10-CM Diagnosis Code G36.1Acute and subacute hemorrhagic leukoencephalitis [Hurst]

ICD-10-CM Codes›G00–G99›G35-G37›G36

ICD-10-CM G36.1
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

G36.1 is a billable ICD-10-CM diagnosis code for acute and subacute hemorrhagic leukoencephalitis [Hurst]. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026). Coders also document this condition as acute disseminated encephalomyelitis. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other nervous system disorders (neither hereditary nor degenerative).

Code Identity

ICD-10-CM Code
G36.1
Billable Status
Yes — Valid for Submission
Code Describes
Acute and subacute hemorrhagic leukoencephalitis [Hurst]
Short Description
Acute and subacute hemorrhagic leukoencephalitis [Hurst]
Same as the full description in the CMS dataset.
Parent Code
G36
Other acute disseminated demyelination

Code Classification

ChapterG00–G99Diseases of the nervous system
SectionG35-G37Demyelinating diseases of the central nervous system
CategoryG36Other acute disseminated demyelination
This CodeG36.1Acute and subacute hemorrhagic leukoencephalitis [Hurst]

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acute disseminated encephalomyelitis
  • Acute encephalitis
  • Acute hemorrhagic leukoencephalitis
  • Demyelination of spinal cord

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.

    • Hurst's disease
    • Leukoencephalitis
      • acute (subacute) hemorrhagic

Clinical ClassificationClinical

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

CCSR NVS020
Other nervous system disorders (neither hereditary nor degenerative)
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Acute Hemorrhagic Leukoencephalitis

    a degenerative brain disorder presenting with acute neurological manifestations. it usually associated with an acute infection or vaccination. it is characterized by brain hemorrhage, vascular necrosis and demyelination. signs and symptoms include fever, headache, vomiting, convulsions and loss of consciousness.

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Convert G36.1 to ICD-9-CMHistory

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

ICD-9-CM
341.8 Cns demyelination NEC
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 G36.1Overview

Is G36.1 (Other acute disseminated demyelination) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report acute and subacute hemorrhagic leukoencephalitis [Hurst] on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What is the ICD-9 equivalent of G36.1?

Under the General Equivalence Mappings, acute and subacute hemorrhagic leukoencephalitis [Hurst] converts to ICD-9-CM 341.8 (cns demyelination NEC). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.