A86 ICD-10-CM Code: Unspecified viral encephalitis
A clear reference for the official code description, hierarchy, and related coding information from the FY 2027 U.S. release.
Official description
A86Unspecified viral encephalitis
ICD-10-CM diagnosis code · United States clinical modification
Where A86 sits
- 1
Chapter 1
Certain infectious and parasitic diseases (A00-B99)
- 2
Section
Viral and prion infections of the central nervous system (A80-A89)
- 3
Category A86
Unspecified viral encephalitis
- 4
Code A86
Unspecified viral encephalitis
Notes for this code
Inclusion terms
- Viral encephalomyelitis NOS
- Viral meningoencephalitis NOS
Code first
No “code first” instruction is listed for A86.
Use additional code
No “use additional code” instruction is listed for A86.
Excludes1
Conditions that should not be reported together with this code.
No Excludes1 note is listed for A86.
Excludes2
Conditions not included here that may be reported separately when present.
No Excludes2 note is listed for A86.
Source and release
- Data release
- U.S. ICD-10-CM · FY 2027
- Effective date
- Oct 1, 2026
- Publisher
- Vero Scribe Inc.
This reference is generated from Vero’s ICD-10-CM description, hierarchy, and code-note dataset. The visible content and structured data share that source.
Frequently asked questions
What does ICD-10-CM code A86 mean?
A86 is the FY 2027 U.S. ICD-10-CM code for “Unspecified viral encephalitis.”
Is A86 a billable or specific ICD-10-CM code?
Yes. In the FY 2027 reference data used on this page, A86 has no child codes and is presented as a billable/specific code. Always confirm the active code set and payer requirements before use.
Where is A86 located in ICD-10-CM?
A86 is listed in Chapter 1, Certain infectious and parasitic diseases (A00-B99), within Viral and prion infections of the central nervous system (A80-A89) (A80–A89), under category A86, Unspecified viral encephalitis.
What coding notes are listed for A86?
Its listed inclusion terms are Viral encephalomyelitis NOS; Viral meningoencephalitis NOS. No code-first instruction is listed. No Excludes1 note is listed. No Excludes2 note is listed.