eMedicine Specialties > Neurology > Movement and Neurodegenerative Diseases

Essential Tremor: Differential Diagnoses & Workup

Author: Deborah A Burke, MD, Consulting Staff, Sub-investigator, Clinician, Movement Disorder/Parkinson's Disease Center, University of South Florida; Investigator, Physician, Roskamp Institute Memory Clinic
Coauthor(s): Robert A Hauser, MD, MBA, Professor of Neurology, Molecular Pharmacology and Physiology, Director, Parkinson's Disease and Movement Disorders Center, University of South Florida; Clinical Chair, Signature Interdisciplinary Program in Neuroscience; Theresa McClain, MSN, ARNP, Parkinson's Disease and Movement Disorders Center, University of South Florida
Contributor Information and Disclosures

Updated: Oct 26, 2009

Differential Diagnoses

Arsenic
Parkinson-Plus Syndromes
Multiple System Atrophy
Thyroid Disease
Neurologic Effects of Caffeine
Torticollis
Parkinson Disease
Wilson Disease

Other Problems to Be Considered

Cerebellar tremor
Dystonia and dystonic tremors
Enhanced physiologic tremor
Isolated chin tremor
Isolated voice tremor
Movement disorders
Orthostatic tremor
Palatal tremor
Rubral tremor
Writer's tremor and other task-specific tremors
Psychogenic tremor

Drug-induced tremors
Antidepressants, especially tricyclics
Beta-agonists
Depakote
Dopamine
Lithium
Metoclopramide
Neuroleptics
Theophylline
Thyroid hormones
Withdrawal of drugs

Metabolism-related tremors
B-12 deficiency
Hyperthyroidism
Hyperparathyroidism
Hypocalcemia
Hyponatremia
Kidney disease
Liver disease

Toxin-related tremors
Alcohol
Arsenic
Caffeine
DDT
Lead
Nicotine
Toluene
Withdrawal of alcohol, cocaine

Workup

Laboratory Studies

  • No biological markers exist for essential tremor.
  • If the family history and examination findings are indicative of essential tremor, no laboratory or imaging studies are required.
  • If the family history and examination findings are not indicative of essential tremor, laboratory and imaging studies should be considered.
  • Laboratory investigations include standard electrolyte panel, thyroid function tests, BUN, creatinine, liver function tests, and serum ceruloplasmin (for Wilson disease).

Imaging Studies

  • Findings on CT scanning and MRI of the head are normal in essential tremor. MRI helps exclude structural and inflammatory lesions (including multiple sclerosis) and Wilson disease. MRI should be performed if the tremor has acute onset or stepwise progression.
  • Midbrain sonography has been suggested as a tool to differentiate essential tremor from Parkinson disease in a study finding that high substantia nigra hyperechogenicity has a high positive predictive value for Parkinson disease. However, another study found a significant increase in substantia nigra hyperechogenicity in patients with essential tremor compared with controls.29,30

Procedures

Electromyography or accelerometry can be used to assess tremor frequency, rhythmicity, and amplitude but are not part of the routine evaluation.

More on Essential Tremor

Overview: Essential Tremor
Differential Diagnoses & Workup: Essential Tremor
Treatment & Medication: Essential Tremor
Follow-up: Essential Tremor
References
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References

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Further Reading

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Keywords

essential tremor, essential tremor treatment, movement disorder, benign essential tremor, familial tremor, senile tremor

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Contributor Information and Disclosures

Author

Deborah A Burke, MD, Consulting Staff, Sub-investigator, Clinician, Movement Disorder/Parkinson's Disease Center, University of South Florida; Investigator, Physician, Roskamp Institute Memory Clinic
Deborah A Burke, MD is a member of the following medical societies: American Academy of Neurology and Movement Disorders Society
Disclosure: Nothing to disclose.

Coauthor(s)

Robert A Hauser, MD, MBA, Professor of Neurology, Molecular Pharmacology and Physiology, Director, Parkinson's Disease and Movement Disorders Center, University of South Florida; Clinical Chair, Signature Interdisciplinary Program in Neuroscience
Robert A Hauser, MD, MBA is a member of the following medical societies: American Academy of Neurology, American Medical Association, American Society of Neuroimaging, and Movement Disorders Society
Disclosure: Allergan Sales, LLC Honoraria Speaking and teaching; Boehringer Ingelheim  Honoraria Consulting; Genzyme Corporation Honoraria Consulting; GlaxoSmithKline Honoraria Consulting; IMPAX Laboratories, Inc. Honoraria Consulting; Novartis Pharmaceuticals Corp. Honoraria Consulting; Schering Plough  Consulting; Solvay Pharmeceuticals Honoraria Consulting; Teva Neuroscience Honoraria Speaking and teaching

Theresa McClain, MSN, ARNP, Parkinson's Disease and Movement Disorders Center, University of South Florida
Theresa McClain, MSN, ARNP is a member of the following medical societies: Sigma Theta Tau International
Disclosure: Teva Consulting fee Consulting; GSK Consulting fee Consulting; Valeant Pharm Consulting fee Consulting; Solvay Consulting fee Consulting; Shering Plough Consulting fee Consulting

Medical Editor

Daniel H Jacobs, MD, Associate Professor of Neurology, University of Central Florida College of Medicine
Daniel H Jacobs, MD is a member of the following medical societies: American Academy of Neurology, American Society of Neurorehabilitation, and Society for Neuroscience
Disclosure: Teva Pharmaceutical Grant/research funds Consulting; Biogen Idex Grant/research funds Independent contractor; Serono EMD Royalty Speaking and teaching; Pfizer Royalty Speaking and teaching; Berlex Royalty Speaking and teaching

Pharmacy Editor

Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine
Disclosure: eMedicine Salary Employment

Managing Editor

Nestor Galvez-Jimenez, MD, MSc, MHA, Chairman, Department of Neurology, Program Director, Movement Disorders, Department of Neurology, Division of Medicine, Cleveland Clinic Florida
Nestor Galvez-Jimenez, MD, MSc, MHA is a member of the following medical societies: American Academy of Neurology, American College of Physicians, and Movement Disorders Society
Disclosure: Nothing to disclose.

CME Editor

Selim R Benbadis, MD, Professor, Director of Comprehensive Epilepsy Program, Departments of Neurology and Neurosurgery, University of South Florida School of Medicine, Tampa General Hospital
Selim R Benbadis, MD is a member of the following medical societies: American Academy of Neurology, American Academy of Sleep Medicine, American Clinical Neurophysiology Society, American Epilepsy Society, and American Medical Association
Disclosure: Nothing to disclose.

Chief Editor

Selim R Benbadis, MD, Professor, Director of Comprehensive Epilepsy Program, Departments of Neurology and Neurosurgery, University of South Florida School of Medicine, Tampa General Hospital
Selim R Benbadis, MD is a member of the following medical societies: American Academy of Neurology, American Academy of Sleep Medicine, American Clinical Neurophysiology Society, American Epilepsy Society, and American Medical Association
Disclosure: Nothing to disclose.

 
 
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