Clinical picture of tick-borne encephalitis among patients hospitalized in 1994 in the Department of Infectious Diseases Medical School Białystok.

In 1994 20 patients of the Department of Infectious Diseases, Medical School Białystok were diagnosed to have tick-borne encephalitis. The etiologic agent was identified by serologic studies of the serum and cerebrospinal fluid (FSME IgM ELISA Immuno Austria). 12 patients (60%) reported a tick bite preceding the disease. Following clinical manifestations were found in the analyzed groups of patients: fever > 37.5 degrees C-20 patients (100%), headache--20 patients(100%), nuchal rigidity-14 patients (70%), abdominal pain -3 patients (15%), arthralgia and myalgia-3 patients (15%), drowsiness and mental confusion -3 patients(15%). Total cell count in CSF ranged from 18 to 348 cells (mean-175). Lymphocytes predominated in 13 cases (68%). The FSME-IgM antibodies were present in serum of 19 patients (95%) and in CSF of only 4 patients (20%). The hospitalization lasted 12-58 days (mean 24 days). In one case the disease was complicated by acute psychosis requiring psychiatric treatment. Severe neurologic complications have been not observed. The prognosis in all cases was good. Our study confirms that tick-borne encephalitis is a current problem in north-eastern Poland. Noteworthy is the fact that only a part of patients give the history of tick bite.