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v1.0.0
ICD-10 Guide
ICD-10 CodesA87.8

A87.8

Other viral encephalitis, not elsewhere classified

BILLABLE STATUSYes
IMPLEMENTATION DATEOctober 1, 2015
LAST UPDATED09/05/2025

Code Description

ICD-10 A87.8 is a billable code used to indicate a diagnosis of other viral encephalitis, not elsewhere classified.

Key Diagnostic Point:

A87.8 refers to viral encephalitis caused by various viral agents that do not fall under more specific classifications. This condition is characterized by inflammation of the brain, which can lead to neurological complications such as seizures, altered mental status, and motor deficits. Common viral etiologies include arboviruses, enteroviruses, and herpesviruses, among others. Patients may present with symptoms such as fever, headache, confusion, and neurological deficits. Diagnosis typically involves clinical evaluation, lumbar puncture for cerebrospinal fluid analysis, and imaging studies. Vaccination status is crucial, as certain viral encephalitides can be prevented through vaccination (e.g., Japanese encephalitis). The management of viral encephalitis often requires supportive care, and in some cases, antiviral therapy may be indicated. The prognosis varies depending on the causative virus and the timeliness of treatment.

Code Complexity Analysis

Complexity Rating: Medium

Medium Complexity

Complexity Factors

  • Variety of potential viral etiologies
  • Overlap with other neurological conditions
  • Need for detailed clinical documentation
  • Potential for misclassification with other encephalitis codes

Audit Risk Factors

  • Inadequate documentation of viral etiology
  • Failure to specify vaccination status
  • Misdiagnosis or overlap with other encephalitis codes
  • Lack of supporting clinical evidence for the diagnosis

Specialty Focus

Medical Specialties

Neurology

Documentation Requirements

Detailed neurological examination findings, imaging results, and laboratory tests.

Common Clinical Scenarios

Patients presenting with acute neurological symptoms, fever, and altered mental status.

Billing Considerations

Ensure clear documentation of the viral etiology and any relevant vaccination history.

Infectious Disease

Documentation Requirements

History of exposure, vaccination status, and laboratory confirmation of viral infection.

Common Clinical Scenarios

Patients with suspected viral infections presenting with neurological symptoms.

Billing Considerations

Document any travel history or exposure to endemic areas for specific viruses.

Coding Guidelines

Inclusion Criteria

Use A87.8 When
  • According to ICD
  • 10 guidelines, A87
  • 8 should be used when the specific viral cause of encephalitis is not documented
  • Coders should ensure that the clinical documentation supports the diagnosis and that other more specific codes are not applicable

Exclusion Criteria

Do NOT use A87.8 When
No specific exclusions found.

Related CPT Codes

87491CPT Code

Viral panel testing

Clinical Scenario

Used to identify the specific viral agent in cases of suspected viral encephalitis.

Documentation Requirements

Document the clinical rationale for testing and any relevant history.

Specialty Considerations

Neurology and Infectious Disease specialists should ensure comprehensive documentation of symptoms and history.

ICD-10 Impact

Diagnostic & Documentation Impact

Enhanced Specificity

ICD-10 Improvements

The transition to ICD-10 has allowed for more specific coding of viral encephalitis, improving the accuracy of data collection and reimbursement processes. A87.8 serves as a catch-all for cases that do not fit into more specific categories, highlighting the need for thorough documentation.

ICD-9 vs ICD-10

The transition to ICD-10 has allowed for more specific coding of viral encephalitis, improving the accuracy of data collection and reimbursement processes. A87.8 serves as a catch-all for cases that do not fit into more specific categories, highlighting the need for thorough documentation.

Reimbursement & Billing Impact

reimbursement processes. A87.8 serves as a catch-all for cases that do not fit into more specific categories, highlighting the need for thorough documentation.

Resources

Clinical References

  • •
    CDC Viral Encephalitis Information

Coding & Billing References

  • •
    CDC Viral Encephalitis Information

Frequently Asked Questions

What should I document to support the use of A87.8?

Document the clinical symptoms, laboratory findings, and any relevant history, including vaccination status and travel history, to support the diagnosis of other viral encephalitis.