Markedly severe dystonia in Japanese encephalitis

Encephalitis has been reported to be a rare cause of severe dystonia. We de scribe five patients with markedly severe dystonia from Japanese encephalit is. These patients with markedly severe dystonia were seen during the past 8 years as a subgroup of 50 patients with Japanese encephalitis. The diagno sis of markedly severe dystonia was based on increasingly frequent episodes of generalized dystonia with bulbar, respiratory, or metabolic derangement or leading to exhaustion or pain. The diagnosis of JE was based on clinico radiologic features and a fourfold increase of hemagglutination-inhibiting antibody titers in paired serum. The outcome of thr patients was defined as a good, partial, or poor recovery on the basis of I-year clinical status. All the patients were males, and their ages ranged from 6 to 19 years. Move ment disorders appeared 1 to 3 weeks after the illness as the level of cons ciousness started improving. During the next 1 to 4 weeks, patients began t o experience markedly severe dystonia. It was associated with marked axial dystonia resulting in opisthotonus and retrocollis in five patients, jaw-op ening dystonia in two patients, teeth clenching in one patient, and oculogy ric crisis and neck deviation in another patient. The attacks of markedly s evere dystonia lasted For 2 to 30 minutes and occurred as many as 20 to 30 times daily. Other developments included fixed limb dystonia in one patient , severe spasticity and rigidity in five patients, and focal muscle wasting in one patient. These patients had only a modest improvement after treatme nt. Markedly severe dystonia abated by 2 to 6 months in all the patients wh o were followed up. Cranial magnetic resonance imaging showed bilateral tha lamic involvement in all patients, brainstem involvement in three patients, and basal ganglia involvement in two patients. At the 3-month follow-up, a ll patients had a poor outcome. At 1 year, one patient had a complete recov ery; one had a partial recovery; and two were bedridden. It can be conclude d that markedly severe dystonia is an important and serious sequela of Japa nese encephalitis and may occur as the result of thalamus, midbrain, or bas al ganglia involvement in various combinations.