Direct invasion of the central nervous system by Mycoplasma pneumoniae: a report of two cases.

We studied two patients with involvement of the central nervous system (CNS) associated with Mycoplasma pneumoniae. One patient had encephalitis and acute cerebellar ataxia, whereas the second had a mixed picture of encephalitic reaction superimposed on a disseminated malignancy of unknown origin. Specific IgM antibodies to M. pneumoniae were detected in the patients' sera but not in their cerebrospinal fluid. M. pneumoniae was repeatedly isolated by cultures from throat swabs and cerebrospinal fluid samples from both patients. Our patients add to previous reports suggesting that CNS involvement may result from direct invasion of the CNS by the pathogen.