ICD-10 G04.81
Billable / Specific MCCOther encephalitis and encephalomyelitis
About ICD-10-CM G04.81
ICD-10-CM code G04.81 represents Other encephalitis and encephalomyelitis. This is a billable/specific code in the Nervous System chapter (block G04). The 2026 edition of ICD-10-CM G04.81 became effective on October 1, 2025.
Coding Tips for G04.81
Specialist guidance from the PayerReady Medical Coding Team. Specificity warnings, HCC capture rules, sequencing notes.
G04.81 is designated MCC for MS-DRG grouping. On inpatient claims, this code can shift the DRG to the with-MCC variant when documented as a present-on-admission secondary diagnosis. Hospital CDI programs flag MCC opportunities during chart review. Failure to capture this code may leave 30 to 80 percent of the inpatient stay revenue unrealized.
Inclusion Terms / Approximate Synonyms
Clinical terms and conditions classified under G04.81. Per CMS ICD-10-CM Tabular 2026.
- Noninfectious acute disseminated encephalomyelitis (noninfectious ADEM)
Inpatient DRG Impact, MCC
codes Other encephalitis and encephalomyelitis. As a Major Complication/Comorbidity (MCC), this can shift the DRG assignment to a higher-weighted category, substantial reimbursement impact.
Medicare LCD Coverage for G04.81
Local Coverage Determinations (LCDs) from CMS MACs that list G04.81 as a covered diagnosis.
Showing top 10 of 669 total . Click a CPT for full coverage scope.
Commercial Payer Coverage
Coverage policies from major commercial payers referencing G04.81.
5 Medicare
3 Aetna
CPT Codes Commonly Billed with G04.81
Procedures frequently paired with this diagnosis based on PayerReady's Dx↔Px linkage data.
- J1551 CMS LCD: Billing and Coding: Immune Globulin CMS LCD
- J1559 CMS LCD: Billing and Coding: Immune Globulin CMS LCD
- J1576 CMS LCD: Billing and Coding: Immune Globulin CMS LCD
- J1558 CMS LCD: Billing and Coding: Immune Globulin CMS LCD
- J1555 CMS LCD: Billing and Coding: Immune Globulin CMS LCD
- 95708 CMS LCD: Billing and Coding: Special Electroencephalography CMS LCD
- 95721 CMS LCD: Billing and Coding: Special Electroencephalography CMS LCD
- 95719 CMS LCD: Billing and Coding: Special Electroencephalography CMS LCD
- 95813 CMS LCD: Billing and Coding: Special Electroencephalography CMS LCD
- 95822 CMS LCD: Billing and Coding: Special Electroencephalography CMS LCD
Convert G04.81 to ICD-9-CM
Per CMS General Equivalence Mappings (GEMs), useful for legacy data review and historical claim analysis.
| ICD-10 | ICD-9 | Mapping Flags |
|---|---|---|
| G04.81 | 32381 | 10000 |
Flags format (5 digits): Approximate · No Map · Combination · Scenario · Choice List. Source: CMS 2017 GEMs (final version).
Codes Adjacent To G04.81
Other codes in section G00-G09 (Inflammatory diseases of the central nervous system).
ICD-10 G04.81, Billing FAQ
Is ICD-10 code G04.81 billable? +
Yes, G04.81 is a billable ICD-10-CM code that can appear as a primary or secondary diagnosis on claims.
What other names or terms map to G04.81? +
ICD-10 G04.81 includes: Noninfectious acute disseminated encephalomyelitis (noninfectious ADEM).
Is G04.81 a CC or MCC for inpatient DRG? +
Yes, this code is designated as MCC. Documenting as a secondary diagnosis on inpatient claims can shift the DRG to a higher-weighted category.
What CPT codes are commonly billed with G04.81? +
Procedures frequently paired with G04.81 include: J1551, J1559, J1576, J1558, J1555.
What ICD-9 codes does G04.81 map to? +
Per CMS GEMs, G04.81 maps to ICD-9 codes: 32381. Useful for legacy data review and historical claim analysis.
Get the full PayerReady toolkit
Free access to CPT/ICD-10 lookup, denial appeals, fee comparator, and claim auditing with credentialing enrollment.
Start free →Run this code through our claim audit tool
Check NCCI bundling, MUE limits, and modifier logic before submission.
Try the auditor →Did this page help?
Quick signal so we know what to improve.
If you want a code reference page that doesn't exist yet, email coding@payerready.com.
Tell us what's missing or wrong: coding@payerready.com. We respond within 5 business days.
Reviewed by the PayerReady Medical Coding Team
Verified against the CMS 2026 code set on July 16, 2026.
Powered by 11K CPT · 98K ICD-10 · 860K MPFS rates · 4.5M NCCI edits · 9.5M NPIs. Our data methodology · About our coding team