ICD-10-CM Tabular Index · Chapter 1 · FY 2026 A86

Unspecified viral encephalitis (A86) ICD-10-CM

The A86 code range covers unspecified viral encephalitis with 1 ICD-10-CM diagnosis codes. 1 of them are billable and valid for claim submission in fiscal year 2026, and the category headers group them but cannot themselves be billed.

✓ Built from the official CMS FY 2026 datasetEffective Oct 1, 2025 – Sep 30, 2026
1
Diagnosis Codes
1
Billable Codes
A86
Code Range
A80–A89
Parent Section

Inclusion Terms

These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.

ICD-10-CM

Codes in the A86 Range 1 codes · 1 billable

1 of 1 shown
  • A86 Unspecified viral encephalitis

About the A86 Code Range

The ICD-10 code A86 is used to classify cases of unspecified viral encephalitis, a brain inflammation caused by viral infections when the exact virus type is not identified.

This code covers various conditions such as acute necrotizing encephalitis, lymphocytic choriomeningitis virus encephalitis, and echovirus encephalitis. These synonyms highlight different viral causes and clinical presentations included under this classification. Healthcare providers and coders use ICD-10 code A86 when documenting central nervous system infections like viral ventriculitis, meningoencephalitis caused by viruses, or chronic viral encephalitis without specification of the exact viral agent. Recognizing these terms helps ensure accurate coding of viral brain infections that lack precise identification, supporting effective medical records and appropriate clinical management.

Questions About This Page

How many billable codes are in the A86 range?

Of the 1 codes in this range, 1 are billable and valid for claim submission from October 1, 2025 through September 30, 2026. Category header codes group them but cannot be reported on claims.

What does the A86 range classify?

The range classifies unspecified viral encephalitis. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.

Related References

Source: CMS FY 2026 ICD-10-CM Tabular List and order file, effective October 1, 2025 through September 30, 2026.