Skip to content
Dx

ICD-10-CM 2027

ICD-10 code for acute necrotizing hemorrhagic encephalopathy

G04.30

Acute necrotizing hemorrhagic encephalopathy, unspecified

From the official ICD-10-CM alphabetic index entry “Encephalopathy (acute) › acute necrotizing hemorrhagic”. Page updated September 29, 2026.

About coding acute necrotizing hemorrhagic encephalopathy

The ICD-10-CM code for acute necrotizing hemorrhagic encephalopathy is G04.30 (Acute necrotizing hemorrhagic encephalopathy, unspecified). The official index lists 3 more specific codes, so check the documentation for details such as type, cause, site or severity before settling on G04.30.

Within G04.3, choose G04.30 (unspecified) only when documentation doesn't support a more specific option: postinfectious acute necrotizing hemorrhagic encephalopathy (G04.31), Postimmunization acute necrotizing hemorrhagic encephalopathy (G04.32) and other acute necrotizing hemorrhagic encephalopathy (G04.39).

As a secondary diagnosis it is an MCC (major complication or comorbidity), which can move an inpatient stay into the highest-paying "with MCC" MS-DRG of its family, unless the principal diagnosis excludes it.

In MS-DRG v44.0, it is part of the grouping logic for DRG 023 (Craniotomy with Major Device Implant or Acute Complex CNS Principal Diagnosis with MCC or Antineoplastic Implant or Epilepsy with Neurostimulator, relative weight 5.7444), DRG 024 (Craniotomy with Major Device Implant or Acute Complex CNS Principal Diagnosis without MCC, relative weight 3.9708), DRG 097 (Non-Bacterial Infection of Nervous System Except Viral Meningitis with MCC, relative weight 3.8226), DRG 098 (Non-Bacterial Infection of Nervous System Except Viral Meningitis with CC, relative weight 2.2706) and DRG 099 (Non-Bacterial Infection of Nervous System Except Viral Meningitis without CC/MCC, relative weight 1.5256), in MDC 01 (Diseases and Disorders of the Nervous System), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.

More specific acute necrotizing hemorrhagic encephalopathy codes (official index)

  • postimmunization G04.32 — Postimmunization acute necrotizing hemorrhagic encephalopathy
  • postinfectious G04.31 — Postinfectious acute necrotizing hemorrhagic encephalopathy
  • specified NEC G04.39 — Other acute necrotizing hemorrhagic encephalopathy

Common questions about acute necrotizing hemorrhagic encephalopathy ICD-10 codes

What is the ICD-10 code for acute necrotizing hemorrhagic encephalopathy?

G04.30 — Acute necrotizing hemorrhagic encephalopathy, unspecified. More specific codes apply when the documentation supports them: G04.32, G04.31, G04.39.

What is the ICD-10 code for postimmunization acute necrotizing hemorrhagic encephalopathy?

G04.32 — Postimmunization acute necrotizing hemorrhagic encephalopathy.

What is the ICD-10 code for postinfectious acute necrotizing hemorrhagic encephalopathy?

G04.31 — Postinfectious acute necrotizing hemorrhagic encephalopathy.

Is G04.30 billable?

Yes. G04.30 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).

Can G04.30 be used as a principal diagnosis?

Yes. The Medicare Code Editor doesn't restrict G04.30 as a principal diagnosis.

Is G04.30 a CC or MCC?

G04.30 is an MCC (major complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.