Cerebellar Ataxia and Overactive Bladder after Encephalitis Affecting the Cerebellum

The cerebellum is one of the regions that contribute to urinary dysfunction in humans. A 43-year-old woman at age 35 had an acute onset of encephalitis that led to fever, generalized convulsion and coma. Six months after the disease onset, she regained consciousness and developed generalized myoclonus, cerebellar ataxia and overactive bladder, e.g., urinary urgency, daytime urinary frequency, and urinary incontinence. Eight years after the disease onset, she was revealed to have cerebellar atrophy on MRI, cerebellar hypoperfusion on SPECT, and detrusor overactivity on urodynamic study. Selective inflammation in the cerebellum seemed to produce cerebellar ataxia and overactive bladder in our case.