Infections of the cerebellum.

Although the cerebellum can be affected by any infection that also involves other parts of the brain parenchyma, cerebrospinal fluid, or nerve roots, a limited range of infections targets cerebellar structures preferentially. Thus, a primarily cerebellar syndrome narrows infectious differential diagnostic considerations. The differential diagnosis of rapidly evolving cerebellar signs suggesting infection includes prescription or illicit drug intoxications or adverse reactions, inflammatory pseudotumor, paraneoplastic processes, and acute postinfectious cerebellitis. This article discusses the diagnosis and differential diagnosis of viral, bacterial, fungal, and prion pathogens affecting the cerebellum in patterns predictable by pace of illness and by involved neuroanatomic structures.