[[Cerebrospinal fluid analysis]] to exclude infections such as tertiary [[syphilis]] or [[subacute sclerosing panencephalitis]] is recommended. Toxicity from [[bismuth]], [[bromide]]s, and [[lithium]] must be ruled-out. [[Myoclonus]] is usually more prominent early in toxic/metabolic disorders than in [[Creutzfeldt-Jakob disease]], and [[seizure]]s in CJD are usually late
((Johnson RT, Gibbs CJ. Creutzfeldt-Jakob Disease and Related Transmissible Spongiform Encephalopathies. N Engl J Med. 1998; 339:1994– 2004))