A89
Billable codeUnspecified viral infection of central nervous system
The ICD-10 code for unspecified viral infection of central nervous system is A89.
Documentation support
General coding-documentation guidance — not a substitute for payer-specific requirements or professional coding judgment.
- •This code describes an unspecified presentation. If the medical record documents a more specific detail (e.g. laterality, type, or affected site), a more specific sibling code should be used instead — see Related codes below.
- •As a general rule, code to the highest level of specificity supported by the documentation in the medical record.
Related codes in this category
- A80Acute poliomyelitisnon-billable header
- A81Atypical virus infections of central nervous systemnon-billable header
- A82Rabiesnon-billable header
- A83Mosquito-borne viral encephalitisnon-billable header
- A84Tick-borne viral encephalitisnon-billable header
- A85Other viral encephalitis, not elsewhere classifiednon-billable header
- A86Unspecified viral encephalitis
- A87Viral meningitisnon-billable header
- A88Other viral infections of central nervous system, not elsewhere classifiednon-billable header
- A89Unspecified viral infection of central nervous system
ICD-9-CM equivalent
Informational only — GEM mappings are approximate, not guaranteed one-to-one equivalents. Verify before use in billing.
- 0499Approximate match
Associated MS-DRGs
A89 can serve as the principal diagnosis for these Medicare Severity Diagnosis-Related Groups.
Informational only — actual DRG assignment also depends on procedures, complications/comorbidities (CC/MCC), discharge status, and payer-specific rules not reflected here.