Cat Scratch Disease-associated Encephalitis Followed by Parkinsonism

Area of Science:

• Infectious Diseases
• Neurology
• Zoonotic Infections

Background:

• Cat scratch disease (CSD), caused by Bartonella henselae, is a common zoonotic infection.
• CSD typically presents as self-limited lymphadenopathy, with encephalitis being a rare complication.
• Neurological sequelae following CSD-associated encephalitis are generally considered to have a benign prognosis.

Observation:

• A 19-year-old woman presented with status epilepticus.
• Diagnosis of CSD-associated encephalitis was confirmed by kitten contact history and high serum IgG titers to Bartonella henselae.
• Initial multimodal treatment improved encephalitis symptoms, but neurological deficits, including spastic paraparesis, remained.

Findings:

• The patient developed parkinsonism months after the acute encephalitis episode.
• The parkinsonism was disproportionate to her age and not characteristic of typical neurodegenerative diseases.
• This case demonstrates an unusual and severe neurological outcome following CSD-associated encephalitis.

Implications:

• CSD-associated encephalitis can lead to severe and persistent neurological sequelae.
• Post-encephalitic parkinsonism is a potential long-term complication of Bartonella henselae encephalitis.
• This highlights the importance of considering CSD in the differential diagnosis of encephalitis presenting with atypical neurological outcomes.