A case of Mycobacterium bovis Bacillus Calmette-Guérin (BCG) strain meningitis and ventriculitis following BCG vaccination.

The Bacillus Calmette-Guérin (BCG) vaccine is widely used worldwide. Intracranial manifestation as an adverse event of BCG is extremely rare. A previously healthy 16-month-old boy was referred to our hospital for eye contact difficulties and progressive gait disturbance lasting two months. He was inoculated with BCG at seven months of age. Brain magnetic resonance imaging (MRI) revealed hydrocephalus with widespread and disseminated enhancement lesions with thickening of the third ventricle floor, and brain tissue pathologically showed non-caseous granulomatous inflammation. Immunosuppressive therapies were initiated because of a provisional diagnosis of neurosarcoidosis. Three months later, a positive polymerase chain reaction (PCR) result for the Mycobacterium tuberculosis complex was obtained. Eventually, M. bovis (BCG Tokyo 172 strain) was identified in the cerebrospinal fluid (CSF) and shunt tube culture. The prolonged use of antituberculosis drugs and multiple shunt replacement surgeries were needed for recovery. There was no evidence of immunodeficiency. Unfortunately, he had severe neurological sequelae of bilateral blindness and neurodevelopmental delay. Our purpose in this report was to highlight the potential for intracranial manifestations of adverse reactions related to BCG vaccination. We propose that the CSF PCR assay of Mycobacterium tuberculosis (MTB) complex should be applied repeatedly in children suspected of intractable neurosarcoidosis, with a history of BCG vaccination.