An Unusual Cause of Generalised Chorea: A Case Report

A 17-year-old girl was admitted to a private hospital with history of being bitten by snake. She had signs of neurotoxic envenomation in the form of breathing difficulty, chest pain, drooping of both eyelids, and difficulty in swallowing. Report of coagulation parameters was not available. She was treated with anti-snake venom and ventilataory support. She made uneventful recovery after a week and was extubated. There was no history of hypotension/hypertension before or after intubation. Following extubation she developed difficulty in vision which improved over next 2 days. On 9th day after snake bite she was noted to have abnormal movements of all four limbs and tongue tremors so she was transferred to our hospital for further management. On arrival to our hospital she was found to have generalized chorea and tongue tremors. There was no other neurological deficit. Initial MRI brain revealed diffusion restrction in both parieto-occipital regions involving white matter. MRI of spinal cord was normal. Repeat MRI brain after one week showed T2 and FLAIR hyperintesities in both caudate and lentiform nuclei in addition. Cerebrospinal fluid (CSF) examination was normal. On the basis of MRI she was diagnosed as a case of PRES (posterior reversible encephalopathy syndrome) and treated with tetrabenazine. She gradually improved and was discharged. Only few cases of PRES following snake bite have been reported and no case of only movement disorder as manifestation of PRES has been reported.