Pseudo-Orthostatic Tremor in Graves' Disease: A Possible Early Sign of Parkinsonism?

Tremor Other Hyperkinet Mov (N Y). 2024 Jul 24:14:39. doi: 10.5334/tohm.924. eCollection 2024.

Abstract

Background: Pseudo-orthostatic tremor is a hyperkinetic movement disorder usually associated with other neurological comorbidities, mainly Parkinson's disease.

Case report: A 65-year-old male presented with unsteadiness and leg tremor while standing. Electrophysiological evaluation confirmed the presence of pseudo-orthostatic tremor. Blood test showed an undiagnosed Graves' disease. A complete remission of tremor was achieved with methimazole. Dopamine transporter scintigraphy showed a mild reduction of the striatal binding, bilaterally.

Discussion: Graves' disease can be associated with pseudo-orthostatic tremor. Thyroid function should be assessed in patients complaining of unsteadiness. The causative role of hyperthyroidism in determining dopaminergic degeneration and uncovering subclinical parkinsonism warrants further investigations.

Keywords: Abnormal DaT-SPECT; Autoimmune thyroiditis; Parkinsonism; Pseudo-orthostatic; Tremor.

Publication types

  • Case Reports

MeSH terms

  • Aged
  • Antithyroid Agents / therapeutic use
  • Graves Disease* / complications
  • Graves Disease* / diagnosis
  • Graves Disease* / physiopathology
  • Humans
  • Male
  • Methimazole / therapeutic use
  • Parkinsonian Disorders* / complications
  • Parkinsonian Disorders* / diagnosis
  • Parkinsonian Disorders* / diagnostic imaging
  • Parkinsonian Disorders* / physiopathology
  • Tremor* / diagnosis
  • Tremor* / etiology
  • Tremor* / physiopathology

Substances

  • Antithyroid Agents
  • Methimazole

Grants and funding

Italian Ministry of Health “Ricerca Corrente 2022–2024” granted to IRCCS Mondino Foundation.