A81
Non-billableAtypical virus infections of central nervous system
A81 is the ICD-10-CM code for Atypical virus infections of central nervous system. It is a non-billable category code — use a more specific child code such as A81.0 for billing.
- Status
- Header (non-billable)
- Chapter
- A00-B99
- Subcodes
- 5
- Edition
- FY2026
A00-B99 Certain infectious and parasitic diseases
What this means — in plain language
MedlinePlus · NIHThe brain, spinal cord, and nerves make up the nervous system. Together they control all the workings of the body. When something goes wrong with a part of your nervous system, you can have trouble moving, speaking, swallowing, breathing, or learning. You can also have problems with your memory, senses, or mood. There are more than 600 neurologic diseases. Major types include: Diseases caused by faulty genes, such…
Read more about Neurologic Diseases at MedlinePlus ↗Source: U.S. National Library of Medicine (MedlinePlus). Informational only — not medical advice.
Includes
- •diseases of the central nervous system caused by prions
Use additional code
- •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-)
Conditions mapped to this code
MedlinePlus · NIHPlain-language health-topic references grounded in MedlinePlus (NIH/NLM).
Frequently asked questions
Source: CMS ICD-10-CM FY2026. For informational purposes only — not medical advice. See our medical disclaimer.
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