An 11-year-old girl was admitted to our hospital with complaint of disturbance of consciousness and muscle weakness. We diagnosed her as having meningoencephalitis because of the pleocytosis in the cerebrospinal fluid (CSF) and diffuse slow EEG waves. Laboratory tests in admission showed that serum passive hemagglutinin titer to Mycoplasma pneumoniae (M. pneumoniae) was 1: 5, 120, serum antibody titer to galactocerebroside (Gc) was 1: 160, and CSF interleukin-6 (IL-6) level was 20, 500pg/ml, but a specific DNA to M. pneumoniae was not detected in CSF using the polymerase chain reaction. Cranial and whole spine MRI were unremarkable. These results suggest that anti-Gc antibody and IL-6 play some roles in the development of mycoplasmal central nervous system involvement.
