ICD-10 Code B57.42 – Meningoencephalitis in Chagas’ Disease (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code B57.42 – Meningoencephalitis in Chagas’ disease
What it is
B57.42 identifies meningoencephalitis caused by Chagas disease, a parasitic infection due to Trypanosoma cruzi. Use it when documentation links central nervous system inflammation to Chagas infection.
Clinical signs
Clinical features vary; refer to documentation. Typical findings may include meningeal irritation, altered mental status, headache, fever, or focal neurologic deficits when the infection involves the brain and meninges.
When to use this code
Use this code when the provider documents meningoencephalitis due to Chagas disease, including confirmed acute or reactivated infection with CNS involvement. It is appropriate when the record clearly attributes neurologic inflammation to T. cruzi. If the note only says Chagas disease without CNS involvement, choose a different code.
Do not use for
Do not use B57.42 for uncomplicated Chagas disease, isolated encephalitis not linked to Chagas, or meningitis from another cause. Check documentation if the organism or site of infection is unclear.
Coding tip
Code the Chagas-related CNS diagnosis only when the provider explicitly documents the relationship between the infection and meningoencephalitis.