ICD-10 Code A17.9 – Tuberculosis of nervous system, unspecified (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code A17.9 – Tuberculosis of nervous system, unspecified
What it is
This code identifies tuberculosis affecting the nervous system when the specific site is not documented. Use it for TB involvement of the brain, meninges, spinal cord, or related nervous tissue when the record remains nonspecific.
Clinical signs
Clinical features vary; refer to documentation. Findings may include neurologic symptoms consistent with central nervous system tuberculosis, but the exact presentation depends on the affected site and severity.
When to use this code
Use A17.9 when the clinician documents tuberculosis of the nervous system without naming a more specific neurologic site. It is also appropriate when the chart confirms nervous system TB, but the available note does not distinguish meninges, brain, or spinal involvement. Check documentation if another TB site is specified.
Do not use for
Do not use this code for pulmonary tuberculosis or for extrapulmonary TB with a clearly documented non-neurologic site. If the record identifies a specific nervous system structure, code that more precise diagnosis instead.
Coding tip
Query for the exact neurologic site whenever possible, because unspecified TB codes are less informative and may miss a more specific option.