2025 ICD-10-CM code A89
Unspecified viral infection of the central nervous system.
Medical necessity for the workup and treatment of a suspected viral CNS infection is established by the presenting signs, symptoms, and clinical findings indicating a potential infection impacting the central nervous system.
Clinicians should document the signs, symptoms, and diagnostic findings pointing to a CNS infection. If the specific virus is identified, the appropriate code should be used instead of A89.
- Certain infectious and parasitic diseases (A00-B99)
- Viral and prion infections of the central nervous system (A80-A89)
In simple words: This code is used when a person has a viral infection of the brain or spinal cord, but the doctor doesn't know exactly which virus is causing it.
This code indicates a viral infection affecting the central nervous system (brain and spinal cord) where the specific virus is not documented.
Example 1: A patient presents with headache, fever, stiff neck, and altered mental status. Initial workup suggests viral meningitis, but further tests are pending to identify the specific virus., A patient with a history of HIV presents with neurological symptoms. Imaging and CSF analysis suggest viral encephalitis, but no specific virus has yet been isolated. , A child exhibits seizures, fever, and lethargy.A viral infection of the CNS is suspected, but the specific viral etiology is unknown at the time of admission.
Documentation should include clinical findings (e.g., fever, headache, neurological deficits), laboratory results (e.g., CSF analysis, blood tests), and imaging findings (e.g., MRI) supporting the diagnosis of a viral CNS infection.If a specific virus is identified later, the coding should be updated accordingly.
- Specialties:Infectious Disease, Neurology, Internal Medicine, Pediatrics, Family Medicine
- Place of Service:Inpatient Hospital, Emergency Room - Hospital, Office, Outpatient Hospital