Acute Necrotizing Encephalopathy as a Complication of Chikungunya Infection.

Background Acute necrotizing encephalopathy (ANE) is a rapidly progressive encephalopathy seen commonly in children triggered by various prodromal viral infections, most common being influenza virus and Human herpes virus-6. Objective We report two rare cases of ANE preceded by Chikungunya infection. Cases A 13-year old girl presented with a three-day history of headache, fever, seizures, and altered sensorium. Another 42-year old man presented with two days history of fever and altered sensorium. Both were suspected to have viral encephalitis. Evaluation revealed serum positivity for Chikungunya virus. In both cases, diagnosis was clinched by characteristic bilateral symmetrical thalamic lesions with central necrosis and hemorrhage along with lesions in cerebral white matter, brainstem, and cerebellum. Conclusions ANE is reported to have high morbidity and mortality. To the best of our knowledge, this is the first report of ANE post-Chikungunya infection. Apart from being rare etiologically, the patients had excellent response to steroids.