Case Report: Dystonic Storm Following Japanese Encephalitis Virus Infection

Dystonic storm (also called status dystonicus) is a neurological emergency characterized by sustained/intermittent involuntary generalized muscle contractions resulting in repetitive painful twisting movements and abnormal postures. It is commonly documented in patients with diagnosed primary dystonic syndromes or secondary dystonic states (i.e., patients with inborn errors of metabolism, dystonic cerebral palsy, Wilson's disease, pantothenate kinase-associated neurodegeneration, and exposure to drugs, among others). However, viral-induced dystonic storm cases have rarely been reported. We describe the case of an 11-year-old girl from rural West Bengal (India) with a dystonic storm after Japanese encephalitis. Generalized dystonic spasms lasted for about 10-20 minutes and occurred 20-30 times/day. They were associated with extreme pain, fever, exhaustion, sweating, tachycardia, tachypnea, pupillary dilatation, arterial hypertension, and mutism and were precipitated by a full bladder and relieved somewhat during sleep. When dystonic spasms abated, she had high-grade generalized rigidity of all four limbs and fixed cervical and truncal dystonia. She was put on invasive ventilation and deep intravenous sedation with continuous midazolam infusion and other supportive measures and had a good clinical recovery. During the 12 months of follow-up, she did not have any other episode of a dystonic storm. However, axial rigidity and intermittent appendicular (upper limb) dystonic posturing were observed. The authors also have briefly discussed the differential diagnoses and treatment plans for such a neurological emergency.