Internal Medicine

0521779407-14 CUNY1086/Karliner 0 521 77940 7 June 4, 2007 21:17

1040 Myoclonus Narcolepsy

tests

■Diagnosis made clinically

■Blood & urine: normal in essential myoclonus

■Brain & spinal cord imaging: normal in essential myoclonus

■EEG: may show abnormalities in myoclonic epilepsies

differential diagnosis

■Epilepsy: excluded by history & EEG

■Degenerative disorders: Alzheimer’s disease, Huntington’s disease,

Wilson’s disease, Lafora body disease excluded clinically

■Infectious disorders: AIDS dementia, prion disorders; viral ence-

phalitis, subacute sclerosing panencephalitis excluded by history &

serologic studies

■Metabolic: drug intoxications or withdrawal; hypo- or hyper-

glycemia; uremia, hepatic encephalopathy excluded by history,

blood & urine studies

■CNS injury: head injury, stroke or tumor excluded by neuroimaging

management

■Depends on cause

specific therapy

■Epileptic myoclonus may respond to valproic acid or benzodi-

azepines

■Postanoxic myoclonus may respond to 5-hydroxytryptophan or lev-

etiracetam

follow-up

■Depends on cause & severity

complications and prognosis

■Depend on cause

NARCOLEPSY

CHAD CHRISTINE, MD

history & physical

■Excessive daytime sleepiness requiring daytime naps in setting of

adequate sleep

■Onset in 2–4th decade

■Cataplexy may also occur & is often triggered by emotional events.

■Sleep paralysis & hypnagogic hallucinations may occur.