ICD-10-CM Code For Other Viral Infections Of Central Nervous System Not Elsewhere Classified: Group Overview

The International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) code group A88 includes viral infections of the central nervous system that are not classified elsewhere, such as unspecified or atypical viral encephalitis and meningoencephalitis. These ICD-10-CM diagnosis codes are used to document clinical encounters involving viral central nervous system infections, capturing disease severity, specific neurologic involvement, and complications relevant to this group. Accurate coding within the ICD-10-CM A88 group supports proper claim adjudication, complete clinical documentation, and appropriate reimbursement.

Customize your policy alerts

Sign up for ICD-10-CM Code For Other Viral Infections Of Central Nervous System Not Elsewhere Classified: Group Overview policy alerts

Get alerted when relevant policies change without checking for updates manually.

Monitor payer policy activity

Receive email alerts as soon as relevant payer policies are published or updated.

ICD-10-CM A88: Other Viral Infections Of Central Nervous System, Not Elsewhere Classified Overview

This group represents viral infections that primarily affect the central nervous system but do not fall into other specified viral encephalitis or meningoencephalitis categories. It targets infections of the brain, meninges, and surrounding neural structures caused by atypical or unspecified viral agents. Accurate coding is important to reflect the complexity of care and to support appropriate reimbursement for services related to diagnosis and management of central nervous system infections.

When to Use

Use a code from this group when a patient has clinical evidence of a viral central nervous system infection but the causative virus or specific encephalitis/meningitis category is not identified or does not have a dedicated code. These codes apply when documentation indicates viral involvement of the brain, meninges, or both without more specific classification elsewhere in ICD-10-CM A00–B99 infectious disease chapter codes.

ICD-10-CM Codes

3 rows

ICD-10-CM Code	Description
A88.0	Enteroviral exanthematous fever [Boston exanthem]
A88.1	Epidemic vertigo
A88.8	Other specified viral infections of central nervous system

DRG Codes

11 rows

DRG Code	Description
075	Viral Meningitis with CC/MCC
076	Viral Meningitis without CC/MCC
091	Other Disorders of Nervous System with MCC
092	Other Disorders of Nervous System with CC
093	Other Disorders of Nervous System without CC/MCC
097	Non-Bacterial Infection of Nervous System Except Viral Meningitis with MCC
098	Non-Bacterial Infection of Nervous System Except Viral Meningitis with CC
099	Non-Bacterial Infection of Nervous System Except Viral Meningitis without CC/MCC
974	HIV with Major Related Condition with MCC
975	HIV with Major Related Condition with CC
976	HIV with Major Related Condition without CC/MCC

Typical Clinical Scenarios

An adult presents to the emergency department with acute onset high fever, severe headache, photophobia, neck stiffness, and rapidly progressive confusion after a recent febrile illness; lumbar puncture shows lymphocytic pleocytosis and PCR testing identifies a non–enteroviral, non–arboviral viral pathogen of the central nervous system. Because this is an acute viral encephalitic process not classified elsewhere, a code from this group is assigned. Typical codes: A88.0, A88.8
A pediatric patient with recent varicella infection develops subacute onset of seizures, altered mental status, and focal neurologic deficits over days to weeks; neuroimaging and CSF studies suggest a postinfectious or atypical viral involvement of the CNS not covered by more specific codes. This subacute central nervous system viral complication is coded using an appropriate code from this group. Typical codes: A88.1, A88.8
An immunocompromised adult undergoing routine inpatient evaluation for persistent cognitive decline and intermittent fevers is found to have chronic viral infection of the central nervous system confirmed by CSF virology without identification of a specific, elsewhere-classified virus; the diagnosis is documented as a chronic or indolent viral CNS infection not elsewhere classified. A code from this group is used to capture the chronic viral CNS condition as a comorbidity affecting care. Typical codes: A88.8

Related Codes

A80-ACUTE-POLIOMYELITIS

ICD-10-CM Code For Acute Poliomyelitis: Group Overview

A81-ATYPICAL-VIRUS-INFECTIONS-CENTRAL-NERVOUS-SYSTEM

ICD-10-CM Code For Atypical Virus Infections Of Central Nervous System: Group Overview

A82-RABIES

ICD-10-CM Code For Rabies: Group Overview

A83-MOSQUITO-BORNE-VIRAL-ENCEPHALITIS

ICD-10-CM Code For Mosquito-Borne Viral Encephalitis: Group Overview

A84-TICK-BORNE-VIRAL-ENCEPHALITIS

ICD-10-CM Code For Tick-Borne Viral Encephalitis: Group Overview

A85-OTHER-VIRAL-ENCEPHALITIS

ICD-10-CM Code For Other Viral Encephalitis Not Elsewhere Classified: Group Overview

A86-UNSPECIFIED-VIRAL-ENCEPHALITIS

ICD-10-CM Code For Unspecified Viral Encephalitis: Group Overview

A87-VIRAL-MENINGITIS

ICD-10-CM Code For Viral Meningitis: Group Overview

A89-UNSPECIFIED-VIRAL-INFECTION-CENTRAL-NERVOUS-SYSTEM

ICD-10-CM Code For Unspecified Viral Infection Of Central Nervous System: Group Overview

Frequently Asked Questions

References

1.CPT® Codes and Descriptions. AAPC. Retrieved Aug 11, 2026.Maintains the CPT code set's official descriptions and guidelines, licensed from the American Medical Association, used as the definitional source for CPT codes on this page.
2.HCPCS Quarterly Update. Centers for Medicare & Medicaid Services (CMS). Retrieved Aug 11, 2026.CMS's quarterly release of HCPCS Level II codes and short/long descriptors, the source for HCPCS code definitions and update history.
3.ICD-10-CM Full Code List. Centers for Medicare & Medicaid Services (CMS). Retrieved Aug 11, 2026.CMS's complete ICD-10-CM diagnosis code list, used to cross-reference diagnosis codes associated with this procedure or service.

Published by

Trek Health powers OpenPayer with a leading commercial payer intelligence platform, seamlessly converting fragmented payer data into actionable insights for provider organizations.

Trek Health ingests and normalizes Transparency in Coverage data and payer policy updates to give provider organizations a clear view of how commercial reimbursement behaves across markets, payers, and services. Our platform transforms raw payer disclosures into structured intelligence that supports contract evaluation, payer negotiations, and service line strategy. By combining market benchmarks with ongoing policy visibility, Trek helps teams identify variability, risk, and opportunity in commercial reimbursement. The result is faster insight, stronger negotiating positions, and more informed financial decisions.

Explore openpayer tools

View all tools

When to Use

ICD-10-CM Codes

3 rows

ICD-10-CM Code	Description
A88.0	Enteroviral exanthematous fever [Boston exanthem]
A88.1	Epidemic vertigo
A88.8	Other specified viral infections of central nervous system

DRG Codes

11 rows

DRG Code	Description
075	Viral Meningitis with CC/MCC
076	Viral Meningitis without CC/MCC
091	Other Disorders of Nervous System with MCC
092	Other Disorders of Nervous System with CC
093	Other Disorders of Nervous System without CC/MCC
097	Non-Bacterial Infection of Nervous System Except Viral Meningitis with MCC
098	Non-Bacterial Infection of Nervous System Except Viral Meningitis with CC
099	Non-Bacterial Infection of Nervous System Except Viral Meningitis without CC/MCC
974	HIV with Major Related Condition with MCC
975	HIV with Major Related Condition with CC
976	HIV with Major Related Condition without CC/MCC

Typical Clinical Scenarios

An adult presents to the emergency department with acute onset high fever, severe headache, photophobia, neck stiffness, and rapidly progressive confusion after a recent febrile illness; lumbar puncture shows lymphocytic pleocytosis and PCR testing identifies a non–enteroviral, non–arboviral viral pathogen of the central nervous system. Because this is an acute viral encephalitic process not classified elsewhere, a code from this group is assigned. Typical codes: A88.0, A88.8
A pediatric patient with recent varicella infection develops subacute onset of seizures, altered mental status, and focal neurologic deficits over days to weeks; neuroimaging and CSF studies suggest a postinfectious or atypical viral involvement of the CNS not covered by more specific codes. This subacute central nervous system viral complication is coded using an appropriate code from this group. Typical codes: A88.1, A88.8
An immunocompromised adult undergoing routine inpatient evaluation for persistent cognitive decline and intermittent fevers is found to have chronic viral infection of the central nervous system confirmed by CSF virology without identification of a specific, elsewhere-classified virus; the diagnosis is documented as a chronic or indolent viral CNS infection not elsewhere classified. A code from this group is used to capture the chronic viral CNS condition as a comorbidity affecting care. Typical codes: A88.8

Related Codes

A80-ACUTE-POLIOMYELITIS

ICD-10-CM Code For Acute Poliomyelitis: Group Overview

A81-ATYPICAL-VIRUS-INFECTIONS-CENTRAL-NERVOUS-SYSTEM

ICD-10-CM Code For Atypical Virus Infections Of Central Nervous System: Group Overview

A82-RABIES

ICD-10-CM Code For Rabies: Group Overview

A83-MOSQUITO-BORNE-VIRAL-ENCEPHALITIS

ICD-10-CM Code For Mosquito-Borne Viral Encephalitis: Group Overview

A84-TICK-BORNE-VIRAL-ENCEPHALITIS

ICD-10-CM Code For Tick-Borne Viral Encephalitis: Group Overview

A85-OTHER-VIRAL-ENCEPHALITIS

ICD-10-CM Code For Other Viral Encephalitis Not Elsewhere Classified: Group Overview

A86-UNSPECIFIED-VIRAL-ENCEPHALITIS

ICD-10-CM Code For Unspecified Viral Encephalitis: Group Overview

A87-VIRAL-MENINGITIS

ICD-10-CM Code For Viral Meningitis: Group Overview

A89-UNSPECIFIED-VIRAL-INFECTION-CENTRAL-NERVOUS-SYSTEM

ICD-10-CM Code For Unspecified Viral Infection Of Central Nervous System: Group Overview

Frequently Asked Questions

References

1.CPT® Codes and Descriptions. AAPC. Retrieved Aug 11, 2026.Maintains the CPT code set's official descriptions and guidelines, licensed from the American Medical Association, used as the definitional source for CPT codes on this page.
2.HCPCS Quarterly Update. Centers for Medicare & Medicaid Services (CMS). Retrieved Aug 11, 2026.CMS's quarterly release of HCPCS Level II codes and short/long descriptors, the source for HCPCS code definitions and update history.
3.ICD-10-CM Full Code List. Centers for Medicare & Medicaid Services (CMS). Retrieved Aug 11, 2026.CMS's complete ICD-10-CM diagnosis code list, used to cross-reference diagnosis codes associated with this procedure or service.

Published by

Trek Health powers OpenPayer with a leading commercial payer intelligence platform, seamlessly converting fragmented payer data into actionable insights for provider organizations.

ICD-10-CM Code For Other Viral Infections Of Central Nervous System Not Elsewhere Classified: Group Overview

Sign up for ICD-10-CM Code For Other Viral Infections Of Central Nervous System Not Elsewhere Classified: Group Overview policy alerts

ICD-10-CM A88: Other Viral Infections Of Central Nervous System, Not Elsewhere Classified Overview

ICD-10-CM Code For Other Viral Infections Of Central Nervous System Not Elsewhere Classified: Group Overview

Sign up for ICD-10-CM Code For Other Viral Infections Of Central Nervous System Not Elsewhere Classified: Group Overview policy alerts

ICD-10-CM A88: Other Viral Infections Of Central Nervous System, Not Elsewhere Classified Overview

When to Use

ICD-10-CM Codes

DRG Codes

Typical Clinical Scenarios

Related Codes

Which diagnoses are included in the ICD-10-CM A88 group?

How does coding within `A88` support reimbursement?

What clinical encounters should use `A88` codes?

Which specific codes comprise the A88 code group?

What DRGs are related to A88-coded diagnoses?

References

When to Use

ICD-10-CM Codes

DRG Codes

Typical Clinical Scenarios

Related Codes

Which diagnoses are included in the ICD-10-CM A88 group?

How does coding within `A88` support reimbursement?

What clinical encounters should use `A88` codes?

Which specific codes comprise the A88 code group?

What DRGs are related to A88-coded diagnoses?

References