A81

Non-billable

Atypical 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.

Status

Non-billable / Header

Block

A80-A89

Child Codes

5

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 syndrome (G14)
  • sequelae of poliomyelitis (B91)
  • sequelae of viral encephalitis (B94.1)

Excludes 2

Conditions not included here, but the patient may have both

  • carrier or suspected carrier of infectious disease (Z22.-)
  • infectious and parasitic diseases complicating pregnancy, childbirth and the puerperium (O98.-)
  • infectious and parasitic diseases specific to the perinatal period (P35-P39)
  • influenza and other acute respiratory infections (J00-J22)

Use Additional Code

Additional codes that should follow this code

Child Codes (5)

Also Known As / Clinical Terms

Frequently Asked Questions

What is ICD-10 code A81?

ICD-10-CM code A81 represents "Atypical virus infections of central nervous system". It 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 you should also code: code to identify 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.

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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.