A39.81 — Meningococcal encephalitis
A39.81 is a billable, specific ICD-10-CM code for meningococcal encephalitis. It is valid for submission on a claim.
Other codes that can never be billed with A39.81
These codes carry an Excludes1 note pointing at A39.81. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading A39.81 alone.
- G05Encephalitis, myelitis and encephalomyelitis in diseases classified elsewhere
Risk adjustment
A39.81 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
A39.81 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.
- A56612Billing and Coding: CT of the Head
- A56771Billing and Coding: Special Electroencephalography
- A57204Billing and Coding: MRI and CT Scans of the Head and Neck
- A57206Billing and Coding: Lumbar MRI
How A39.81 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 A39.81.
- Encephalitis›meningococcal
- Meningoencephalitis›epidemic
- Meningomyelitis›meningococcal
- Infection, infected, infective›meningococcal›brain
Related codes at this level
Codes that share A39.8. If A39.81 is not quite right, the correct code is usually one of these.
Questions about A39.81
- Is A39.81 a billable ICD-10-CM code?
- Yes. A39.81 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does A39.81 sit in the tabular list?
- Certain infectious and parasitic diseases (A00-B99), in the block Other bacterial diseases (A30-A49).