G04.31 — Postinfectious acute necrotizing hemorrhagic encephalopathy
G04.31 is a billable, specific ICD-10-CM code for postinfectious acute necrotizing hemorrhagic encephalopathy. It is valid for submission on a claim.
Risk adjustment
G04.31 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.
Medicare coverage
G04.31 is named in 8 Medicare coverage policies — 8 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.
- A56551Billing and Coding: Visual Fields Testing
- A56771Billing and Coding: Special Electroencephalography
- A56799Billing and Coding: Visual Fields Testing
- A57204Billing and Coding: MRI and CT Scans of the Head and Neck
How G04.31 is indexed
Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to G04.31.
- Encephalomyelitis›acute necrotizing hemorrhagic›postinfectious
- Encephalopathy›acute necrotizing hemorrhagic›postinfectious
- Encephalitis›acute›necrotizing hemorrhagic›postinfectious
Related codes at this level
Codes that share G04.3. If G04.31 is not quite right, the correct code is usually one of these.
Questions about G04.31
- Is G04.31 a billable ICD-10-CM code?
- Yes. G04.31 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does G04.31 sit in the tabular list?
- Diseases of the nervous system (G00-G99), in the block Inflammatory diseases of the central nervous system (G00-G09).