ICD-10-CM Codes
G00-G99 Diseases of the nervous system
G30-G32 Other degenerative diseases of the nervous system
Other degenerative diseases of nervous system, not elsewhere classified G31

Other degenerative diseases of nervous system, not elsewhere classified G31-

Use Additional

Use Additional Help

Certain conditions have both an underlying etiology and multiple body system manifestations due to the underlying etiology. For such conditions the ICD-10-CM has a coding convention that requires the underlying condition be sequenced first followed by the manifestation. Wherever such a combination exists there is a "use additional code" note at the etiology code, and a "code first" note at the manifestation code. These instructional notes indicate the proper sequencing order of the codes, etiology followed by manifestation. In most cases the manifestation codes will have in the code title, "in diseases classified elsewhere." Codes with this title are a component of the etiology/manifestation convention. The code title indicates that it is a manifestation code. "In diseases classified elsewhere" codes are never permitted to be used as first listed or principle diagnosis codes. They must be used in conjunction with an underlying condition code and they must be listed following the underlying condition.

For codes
ICD-10-CM Diagnosis Code G31.0
Frontotemporal dementia
G31.0-
ICD-10-CM Diagnosis Code G31.83
Dementia with Lewy bodies
Applicable To
- Dementia with Parkinsonism
- Lewy body dementia
- Lewy body disease
G31.83
,
ICD-10-CM Diagnosis Code G31.85
Corticobasal degeneration
G31.85-
ICD-10-CM Diagnosis Code G31.9
Degenerative disease of nervous system, unspecified
G31.9
, use additional code to identify:
dementia with behavioral disturbance (
ICD-10-CM Diagnosis Code F02.81
Dementia in other diseases classified elsewhere with behavioral disturbance
Applicable To
- Dementia in other diseases classified elsewhere with aggressive behavior
- Dementia in other diseases classified elsewhere with combative behavior
- Dementia in other diseases classified elsewhere with violent behavior
- Major neurocognitive disorder in other diseases classified elsewhere with aggressive behavior
- Major neurocognitive disorder in other diseases classified elsewhere with combative behavior
- Major neurocognitive disorder in other diseases classified elsewhere with violent behavior
Use Additional
- code, if applicable, to identify wandering in dementia in conditions classified elsewhere (Z91.83)
F02.81
)
dementia without behavioral disturbance (
ICD-10-CM Diagnosis Code F02.80
Dementia in other diseases classified elsewhere without behavioral disturbance
Applicable To
- Dementia in other diseases classified elsewhere NOS
- Major neurocognitive disorder in other diseases classified elsewhere
F02.80
)

Type 2 Excludes

Type 2 Excludes Help

A type 2 excludes note represents "not included here". A type 2 excludes note indicates that the condition excluded is not part of the condition it is excluded from but a patient may have both conditions at the same time. When a type 2 excludes note appears under a code it is acceptable to use both the code (G31) and the excluded code together.

Reye's syndrome (
ICD-10-CM Diagnosis Code G93.7
Reye's syndrome
Code First
- poisoning due to salicylates, if applicable (T39.0-, with sixth character 1-4)
Use Additional
- code for adverse effect due to salicylates, if applicable (T39.0-, with sixth character 5)
G93.7
)

Codes

G31 Other degenerative diseases of nervous system, not elsewhere classified
- G31.0 Frontotemporal dementia
  - G31.01 Pick's disease
  - G31.09 Other frontotemporal dementia
- G31.1 Senile degeneration of brain, not elsewhere classified
- G31.2 Degeneration of nervous system due to alcohol
- G31.8 Other specified degenerative diseases of nervous system
  - G31.81 Alpers disease
  - G31.82 Leigh's disease
  - G31.83 Dementia with Lewy bodies
  - G31.84 Mild cognitive impairment, so stated
  - G31.85 Corticobasal degeneration
  - G31.89 Other specified degenerative diseases of nervous system
- G31.9 Degenerative disease of nervous system, unspecified

Other degenerative diseases of nervous system, not elsewhere classified G31-

Frontotemporal dementia

Dementia with Lewy bodies

Corticobasal degeneration

Degenerative disease of nervous system, unspecified

Dementia in other diseases classified elsewhere with behavioral disturbance

Dementia in other diseases classified elsewhere without behavioral disturbance

Reye's syndrome