Is G04.02 a billable ICD-10-CM code?

Yes. G04.02 is a billable, specific ICD-10-CM code and is valid for submission on a claim.

Where does G04.02 sit in the tabular list?

Diseases of the nervous system (G00-G99), in the block Inflammatory diseases of the central nervous system (G00-G09).

G04.02

G04.02 — Postimmunization acute disseminated encephalitis, myelitis and encephalomyelitis

Billable / specific codeICD-10-CM

G04.02 is a billable, specific ICD-10-CM code for postimmunization acute disseminated encephalitis, myelitis and encephalomyelitis. It is valid for submission on a claim.

Use additional code

Add a secondary code to capture the detail described below.

code to identify the vaccine (T50.A-, T50.B-, T50.Z-)

Inclusion terms

Alternative wordings a physician may use in the chart for this same code.

Encephalitis, post immunization
Encephalomyelitis, post immunization

Risk adjustment

G04.02 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

G04.02 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 G04.02 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 G04.02.

Encephalitis›following vaccination or other immunization procedure
Encephalitis›postimmunization
Encephalitis›postvaccinal
Encephalomyelitis›postvaccinal
Leukoencephalopathy›postimmunization and postvaccinal
Meningoencephalomyelitis›postimmunization or postvaccination
Myelitis›postimmunization
Myelitis›postvaccinal
Complication›vaccination›encephalitis or encephalomyelitis
Complication›vaccination›myelitis
Encephalitis›due to›smallpox inoculation
Encephalomyelitis›acute disseminated›postimmunization

Related codes at this level

Codes that share G04.0. If G04.02 is not quite right, the correct code is usually one of these.

Questions about G04.02

Is G04.02 a billable ICD-10-CM code?: Yes. G04.02 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does G04.02 sit in the tabular list?: Diseases of the nervous system (G00-G99), in the block Inflammatory diseases of the central nervous system (G00-G09).