An 18‐year‐old girl presented with headache, fever, altered sensorium, and abnormal involuntary twisting movements of limbs for 1 month. On examination, she had generalized dystonia and parkinsonism (reduced facial expression and blink rate; see Video 1). Her cerebrospinal fluid (CSF) analysis showed lymphocytic pleocytosis with elevated protein (296 mg/dL) and normal sugar (70 mg/dL). She was diagnosed as a case of dengue encephalitis based on positive immunoglobulin G antibodies in CSF. Her nonstructural 1 antigen by enzyme‐linked immunosorbent assay for dengue virus was also positive. CSF and serological investigations were negative for Japanese encephalitis (JE) and herpes simplex encephalitis. Her MRI of the brain showed the characteristic double‐doughnut sign observed in dengue encephalitis (Fig. 1A–H).1 She was treated with tablets of levodopa + carbidopa (100 + 25 mg four times daily) and trihexyphenidyl (2 mg three times daily) for 15 days and showed mild improvement.
Figure 1.
MRI of the brain showed bilateral T2 (A) and FLAIR (B) hyperintensities in bilateral thalami regions also showing areas of diffusion restriction on diffusion‐weighted images (DWIs) (C) and apparent diffusion coefficient (ADC) images (D) and foci of blooming within on susceptibility‐weighted images (E) characteristic of the double‐doughnut sign observed in dengue encephalitis.1 The corresponding areas show hypointensity surrounded by hyperintensity on T1 (F) sequences. There were additional lesions in the pons and right cerebellum showing diffusion restriction on DWI (G) and ADC (H) sequences.
In our patient, generalized dystonia/parkinsonism may be attributed to the bilateral thalamic involvement suggested by the double‐doughnut sign on the MRI brain, which is characteristically observed in dengue encephalitis.1 However, there are reports of the double‐doughnut sign on the MRI brain in JE, as well as in other neurotropic infections.2 These lesions are hyperintense on T2 and fluid‐attenuated inversion recovery (FLAIR) images with patchy diffusion restriction.1 Dengue fever can have various neurological manifestations like encephalitis, encephalopathy, neuromuscular involvement, acute disseminated encephalomyelitis, transverse myelitis, and cerebellar syndromes.3, 4 Initially, dengue was considered a non‐neurotropic virus; however, recent studies suggest neurotropism and neuroinvasion targeting monocytes, macrophages, and dendritic cells.4 Movement disorders are observed in 11% of dengue encephalitis patients and include parkinsonism and dystonia.5
Dystonia is most commonly seen in which encephalitis?
A. Herpes simplex encephalitis
B. Japanese encephalitis
C. West Nile virus encephalitis
D. HIV encephalitis
B. Japanese encephalitis
Author Roles
(1) Research Project: A. Conception, B. Organization, C. Execution; (2) Statistical Analysis: A. Design, B. Execution, C. Review and Critique; (3) Manuscript Preparation: A. Writing of the First Draft, B. Review and Critique.
A.M.: 1A, 1B, 1C, 2A, 3A, 3B
S.P.: 1A, 1B, 2A, 2C, 3A, 3B
Disclosures
Ethical Compliance Statement: The authors confirm that the approval of an institutional review board was not required for this work. We have taken the consent of the patient for the publication of the video. We confirm that we have read the Journal's position on issues involved in ethical publication and affirm that this work is consistent with those guidelines.
Funding Sources and Conflicts of Interest: The authors report no sources of funding and no conflicts of interest.
Financial Disclosures for previous 12 months: The authors declare that there are no disclosures to report.
Supporting information
Video 1. An 18‐year‐old girl diagnosed with dengue encephalitis has generalized dystonia, which is more prominent on walking. She also has lingual dystonia, slow eye movement, and parkinsonism (reduced facial expression and blink rate).
Relevant disclosures and conflicts of interest are listed at the end of this article.
References
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Associated Data
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Supplementary Materials
Video 1. An 18‐year‐old girl diagnosed with dengue encephalitis has generalized dystonia, which is more prominent on walking. She also has lingual dystonia, slow eye movement, and parkinsonism (reduced facial expression and blink rate).