The First Case of Bacillus Calmette-Guérin-Induced Autoimmune Encephalitis

Area of Science:

• Neuroimmunology
• Oncology
• Urology

Background:

• Intravesical bacillus Calmette-Guerin (BCG) is a standard treatment for non-muscle invasive bladder cancer.
• Systemic complications from BCG therapy are rare but can be severe.

Purpose of the Study:

• To report the first case of BCG-induced autoimmune encephalitis following intravesical therapy.
• To highlight a rare but serious neurological complication of BCG treatment.

Main Methods:

• A 69-year-old male patient presented with fever, headache, and impaired consciousness three days after intravesical BCG therapy.
• Initial diagnosis of viral encephalitis was treated with acyclovir without improvement.
• Autoimmune encephalitis was suspected, leading to steroid therapy and plasmapheresis.

Main Results:

• Steroid therapy resulted in marked clinical improvement.
• Plasmapheresis, in addition to steroids, led to further recovery.
• The patient remained stable and relapse-free at the time of reporting.

Conclusions:

• This is the first reported case of autoimmune encephalitis triggered by intravesical BCG therapy.
• BCG therapy can induce rare neurological complications such as autoimmune encephalitis.
• Prompt diagnosis and management with immunosuppressants and plasmapheresis are crucial for favorable outcomes.