An Interesting Case of Dengue Encephalitis With Parkinsonism Sequela.

Expanded dengue syndrome has been associated with various neurological manifestations. In this report, we present a rare and interesting case of parkinsonism secondary to dengue encephalitis in a young female. A 25-year-old female was admitted to the ICU with high-grade fever, generalized weakness, and altered sensorium for two days. Meningoencephalitis workup was negative but she tested positive for dengue non-structural 1 (NS1) antigen. MRI brain showed a "double doughnut sign" consistent with viral encephalitis. She was managed with neuroprotective measures, a short course of steroids, and invasive mechanical ventilation via tracheostomy. During the course of her treatment, she developed left upper limb rigidity, involuntary movements, and gait abnormalities with generalized bradykinesia suggestive of dengue-associated parkinsonism. She responded well to trihexyphenidyl and levodopa with significant neurological recovery and was discharged from the hospital in a condition where she could independently walk with significant improvement in dystonia. Central nervous system involvement has been well documented in arboviral illnesses caused by neurotropic viruses. Dengue encephalitis with sequelae like parkinsonism is potentially treatable when identified appropriately and in a timely manner.