A81 is a non-billable/non-specific diagnosis code from the 2025 ICD-10-CM used to classify the following condition: Atypical virus infections of central nervous system.
Includes
Diseases of the central nervous system caused by prions
Use additional code
Code, if applicable, to identify:
Dementia with behavioral disturbance (F02.81-, F02.A1-, F02.B1-, F02.C1-)
Dementia with mood disturbance (F02.83, F02.A3, F02.B3, F02.C3)
Dementia with psychotic disturbance (F02.82, F02.A2, F02.B2, F02.C2)
Dementia without behavioral disturbance (F02.80, F02.A0, F02.B0, F02.C0)
Mild neurocognitive disorder due to known physiological condition (F06.7-)
Codes
Versions
2025
No changes
2024
No changes
2023
Code changed
Use additional code
code to identify:dementia with behavioral disturbance (F02.81)dementia without behavioral disturbance (F02.80)
- code, if applicable, to identify:
- dementia with anxiety (F02.84, F02.A4, F02.B4, F02.C4)
- dementia with behavioral disturbance (F02.81-, F02.A1-, F02.B1-, F02.C1-)
- dementia with mood disturbance (F02.83, F02.A3, F02.B3, F02.C3)
- dementia with psychotic disturbance (F02.82, F02.A2, F02.B2, F02.C2)
- dementia without behavioral disturbance (F02.80, F02.A0, F02.B0, F02.C0)
- mild neurocognitive disorder due to known physiological condition (F06.7-)
2022
No changes
2021
No changes
2020
No changes
2019
No changes
2018
No changes
2017
No changes
2016
New code