ICD-10 Code B27.02 – Gammaherpesviral mononucleosis with meningitis (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code B27.02 – Gammaherpesviral mononucleosis with meningitis
What it is
B27.02 identifies infectious mononucleosis caused by a gammaherpesvirus, with meningitis as the documented complication. Use it when the record clearly links the mononucleosis to meningeal involvement.
Clinical signs
Clinical features vary; refer to documentation. Typical meningitis findings may include headache, neck stiffness, fever, and photophobia, alongside mononucleosis features such as fatigue, sore throat, or lymphadenopathy.
When to use this code
Use B27.02 when the provider documents gammaherpesviral mononucleosis and specifies meningitis. It also fits cases where the meningitis is described as a complication of the viral illness. If the organism or complication is not stated clearly, check documentation.
Do not use for
Do not use this code for mononucleosis without meningitis, or for meningitis from another cause. If the chart only says “viral meningitis” or “infectious mononucleosis,” code the documented condition instead.
Coding tip
Confirm both the gammaherpesviral etiology and the meningitis complication in the provider’s note before assigning B27.02.