ICD-10 Code B26.1 – Mumps meningitis (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code B26.1 – Mumps meningitis
What it is
B26.1 identifies meningitis caused by mumps virus. Use it when the record documents mumps infection with inflammation of the meninges, the protective tissues around the brain and spinal cord.
Clinical signs
Clinical features vary; refer to documentation. Typical meningitis findings may include headache, fever, neck stiffness, and cerebrospinal fluid evidence of meningeal inflammation in the setting of mumps.
When to use this code
Use B26.1 when the provider documents mumps meningitis, mumps with meningitis, or a confirmed mumps-related central nervous system complication. Code it when the meningitis is specifically attributed to mumps rather than listed as unspecified viral meningitis. If the chart does not clearly link the meningitis to mumps, check documentation.
Do not use for
Do not use this code for uncomplicated mumps, parotitis without meningitis, or meningitis from another cause. If the cause is not stated or the record is ambiguous, check documentation.
Coding tip
Look for explicit provider wording that connects meningitis to mumps before assigning B26.1.