Post-infectious leukoencephalopathy as a complication of Mycoplasma pneumoniae infection.

We report a 9-year-old girl with leukoencephalopathy who demonstrated serologic evidence of a Mycoplasma pneumoniae infection. She had a mild upper respiratory tract illness 10 days prior to admission and developed walking difficulty and somnolence. The neurologic symptoms progressed to semicoma and spastic paraplegia over a few days but began to improve on the fourth day. Cranial computed tomography on the eleventh day revealed an area of diffuse low density in the white matter. Cerebrospinal fluid examination was normal. The patient recovered with minimal motor deficits. Cranial computed tomography was normal. She was diagnosed as having leukoencephalopathy complicated by a Mycoplasma pneumoniae infection. The pathogenesis of this infection is believed to be an allergic reaction to Mycoplasma pneumonia of the central nervous system as well as an acute disseminated encephalomyelitis.