Movement disorders of probable infectious origin

Background: Movement disorders (MDs) associated with infections remains an important debilitating disorder in the Asian countries. Objectives: The objective of the following study is to report the clinical and imaging profile of a large cohort of patients with MDs probably associated with infection. Materials and Methods: This was a chart review of 35 patients (F:M-15:20) presenting with MD in the Neurology services of National Institute of Mental Health and Neurosciences, India. The demographic profile, type of infection, time from infection to MD, phenomenology of MD and magnetic resonance imaging (MRI) findings were reviewed. Results: The mean age at presentation was 22.6 13.3 years, (5-60), age of onset of MD was 15.7 15 years, and duration of symptoms was 6.9 8.1 years (42 days to 32 years). The mean latency of onset of MD after the infection was 5.9 4.2 weeks. The phenomenology of MD were: (1) Pure dystonia-28.6%, (2) dystonia with choreoathetosis-22.9%, (3) Parkinsonism-14.6%, (4) pure tremor, hemiballismus, myoclonus and chorea-2.9% each, and (5) mixed MD-22.9%. Most often the MD was generalized (60%), followed by right upper limb (31.4%) and left upper limb (8.6%). A viral encephalitic type of neuroinfection was the most common infection (85.7%), which was associated with MD. Abnormalities of brain MRI, seen in 79.2%, included signal changes in (1) thalamus-52.0%, (2) putamen and subcortical white matter-16% each, (3) pons-12%, (4) striatopallidum, striatum and grey matter-8% each, and (5) caudate, cerebellum, lentiform nucleus, midbrain and subthalamic nucleus-4.0% each. Conclusions: MDs associated with infection were the most often post-encephalitic. Dystonia was the most common MD, and thalamus was the most common anatomical site involved.