Introduction: Acute cerebellitis is an uncommon complication following Mycoplasma pneumoniae infection. A benign and self-limited course has been described in the few reports found of this association.
Case reports: We report two patients with an apparently M. pneumoniae-induced acute cerebellitis that resulted in cerebellar atrophy. Patients presented with a cerebellar syndrome including ataxia, hypotonia, dysarthric speech and dysmetria, which were preceded by signs of respiratory infection. Initial brain magnetic resonance imaging (MRI) in case 1 was normal but in case 2 it displayed striking cerebellar swelling, small fourth ventricle and supratentorial ventriculomegaly which was self-limited and did not require neurosurgical intervention. Serological studies confirmed a recent M. pneumoniae infection. Case 1 has followed an unfavourable clinical course, with incomplete resolution of cerebellar dysfunction, while case 2 has remained asymptomatic. Follow-up brain MRI have demonstrated prominent cerebellar atrophy in both patients.
Conclusions: M. pneumoniae infection should be considered in those patients with acute cerebellitis showing an incomplete resolution of cerebellar dysfunction or those who develop early cerebellar atrophy. The presenting MRI findings do not seem to predict final neurological outcome.