Description

An 82-year-old man was referred to our department for re-evaluation of parkinsonism. The patient had a 2-year history of parkinsonism followed by dementia and was treated with 300 mg of levodopa/decarboxylase inhibitor. The patient previously had a significant response of motor symptoms including rest and re-emergent tremor to levodopa therapy. The medical history included chronic subdural haematoma. Neurological examination showed bradykinesia and rigidity involving the neck and upper and lower extremities. Resting tremor at the jaw, tongue and right foot was observed. Re-emergent tongue tremor was observed (see online supplementary video). The patient was in Hoehn and Yahr stage 5 in an ‘on’ state. He had dementia with visual hallucinations. Brain MRI showed diffuse cortical atrophy with preserved midbrain tegmentum and pons. A diagnosis of Parkinson’s disease (PD) with dementia was made. Reduced uptake of the early and delayed heart-to-mediastinum ratios of cardiac 123I-metaiodobenzylguanidine scintigraphy and anosmia supported the diagnosis.

Resting tremor is the characteristic motor sign in PD, predominantly affecting the unilateral upper extremity, but it can be seen in the other body regions including the lips, jaw and tongue with a uniform frequency of 4 to 6 Hz.1 PD-related postural tremor, ‘re-emergent tremor’, is different from essential tremor in the delayed appearance and a similar frequency to rest tremor. Re-emergent tremor is usually observed in the hand of the patient, but can affect the other body parts.2 The re-emergent tongue tremor as the first manifestation of PD has been rarely described.3 We here report resting and re-emergent nature of the tongue tremor in PD.