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Post-encephalitic tremor and delayed-onset parkinsonism
C Colosimo1, M C Gori, M Inghilleri
1Dipartimento di Scienze Neurologiche, Università La Sapienza, vl. dell'Università 30, I-00185 Rome, Italy.
Abstract:
Movement disorders of various types may occur in relation to viral infections of the central nervous system. They manifest themselves as obvious signs at clinical onset or during the acute phase of an encephalitis (myoclonus, tremor, or parkinsonism), or appear as later sequelae decades after the illness. We describe here a man who developed an unusual movement disorder after a probable viral encephalitis in his childhood. This consisted of a tremor (3-4Hz frequency and 100-150ms duration) of the neck, left shoulder and arm, which persisted unchanged during the ensuing years. The patient regarded this abnormal movement as annoying, but otherwise it did not impair his lifestyle. He subsequently developed the clinical picture of parkinsonism many decades after the onset of tremor, and we speculate that both tremor and parkinsonism can be considered sequelae of encephalitis, but each with a different time-course. The left-sided jerky tremor was an immediate sequela in the childhood; whereas, the rigid-akinetic parkinsonian picture represented a later sequela of the infection in old age. The injured site responsible for both the segmental tremor and the parkinsonism presumably involved the brainstem.
Insights
Viral encephalitis can cause delayed movement disorders. This case highlights a patient with childhood tremor and later-onset parkinsonism, both potentially resulting from a single childhood viral infection affecting the brainstem.
Area of Science:
- Neurology
- Infectious Diseases
- Movement Disorders
Background:
- Viral infections of the central nervous system can lead to diverse movement disorders.
- These disorders may manifest acutely during encephalitis or as long-term sequelae.
Purpose of the Study:
- To describe an unusual case of movement disorder following probable viral encephalitis.
- To explore the distinct temporal patterns of tremor and parkinsonism as sequelae of encephalitis.
Main Methods:
- Case report detailing a patient's neurological history.
- Clinical observation of tremor and parkinsonism.
- Speculation on the neuroanatomical basis of the sequelae.
Main Results:
- A patient developed a persistent left-sided tremor in childhood after probable viral encephalitis.
- Decades later, the same patient developed parkinsonism.
- Both conditions are hypothesized to be sequelae of the initial encephalitis, originating from brainstem involvement.
Conclusions:
- Viral encephalitis can result in both immediate and significantly delayed movement disorders.
- Tremor and parkinsonism may represent distinct temporal sequelae of the same central nervous system viral insult.
- The brainstem is a likely site of injury responsible for these diverse neurological manifestations.
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