A81
Non-billableAtypical virus infections of central nervous system
Atypical virus infections of central nervous system
This is a header/category code. For billing purposes, use a more specific child code from the list below.
Coding Notes
Includes
Conditions included under this code
- diseases generally recognized as communicable or transmissible
- diseases of the central nervous system caused by prions
Excludes 1
Codes that cannot be used together with this code (mutual exclusion)
- certain localized infections - see body system-related chapters
- •postpolio syndromeG14
- •sequelae of poliomyelitisB91
- •sequelae of viral encephalitisB94.1
Excludes 2
Conditions not included here, but the patient may have both
Use Additional Code
Additional codes that should follow this code
- •code to identify resistance to antimicrobial drugsZ16
- code, if applicable, to identify:
- •dementia with anxiety, A4, B4, C4)F02.84, F02, F02, F02
- •dementia with behavioral disturbance, A1-, B1-, C1-)F02.81, F02, F02, F02
- •dementia with mood disturbance, A3, B3, C3)F02.83, F02, F02, F02
- •dementia with psychotic disturbance, A2, B2, C2)F02.82, F02, F02, F02
- •dementia without behavioral disturbance, A0, B0, C0)F02.80, F02, F02, F02
- •mild neurocognitive disorder due to known physiological conditionF06.7
Child Codes (5)
ICD-11 Equivalents(1)
ICD-11 Equivalents
View full mappingCorresponding ICD-11 codes from the WHO crosswalk mapping
Also Known As / Clinical Terms(4)
Frequently Asked Questions
What is the ICD-10 code for atypical virus infections of central nervous system?
The ICD-10-CM code for atypical virus infections of central nervous system is A81. The full clinical description is "Atypical virus infections of central nervous system". A81 is a non-billable header code. Use a more specific child code for billing purposes.
What does ICD-10 code A81 mean?
ICD-10-CM code A81 represents “Atypical virus infections of central nervous system”. It is classified under Chapter 1: Certain Infectious and Parasitic Diseases and is a non-billable header code. Use a more specific child code for billing purposes.
Is A81 a billable code?
No, A81 is a non-billable header code. You need to use one of its more specific child codes for billing. There are 5 child codes under A81.
What chapter is A81 in?
A81 is in Chapter 1: Certain Infectious and Parasitic Diseases (codes A00-B99).
What codes cannot be used with A81?
A81 has Excludes1 notes indicating codes that cannot be used together with it, including: certain localized infections - see body system-related chapters; postpolio syndrome (G14); sequelae of poliomyelitis (B91); and 1 more.
What are the subcategories under A81?
A81 has 5 child codes, including: A81.0 (Creutzfeldt-Jakob disease), A81.1 (Subacute sclerosing panencephalitis), A81.2 (Progressive multifocal leukoencephalopathy), A81.8 (Other atypical virus infections of central nervous system), and 1 more.
Are additional codes required with A81?
Yes, when using A81, also report: resistance to antimicrobial drugs (Z16.-); 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-).
What are the UMLS CUIs for A81?
A81 is linked to 2 UMLS Concept Unique Identifiers: C0851226, C4290047. The UMLS (Unified Medical Language System) integrates multiple biomedical vocabularies maintained by the U.S. National Library of Medicine.
How does A81 relate to ICF functioning codes?
ICF (International Classification of Functioning, Disability and Health) codes describe how conditions like atypical virus infections of central nervous system affect a person's functioning — body functions, activities, participation, and environmental factors. AutoICD provides ICF Core Sets for 12+ conditions and can map clinical text to ICF categories automatically. Browse the ICF directory to explore functioning codes.
What is the ICD-11 equivalent of A81?
A81 maps to the ICD-11 code: 1C8Z (Viral infections of the central nervous system, unspecified).
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Includes SNOMED Clinical Terms® (SNOMED CT®) used by permission of SNOMED International. Includes content from the UMLS Metathesaurus, courtesy of the U.S. National Library of Medicine.