RESUMO
Tick-borne encephalitis is a neuroinfection widely distributed in the Euro-Asia region. Primarily, the virus is transmitted by the bite of infected ticks. From 2000-2019, the total number of confirmed cases in Europe reported to the European Centre for Disease Prevention and Control was 51,519. The number of cases decreased in 2014 and 2015; however, since 2015, a growing number of cases have been observed, with the involvement of countries in which TBE has not been previously reported. The determinant factors for the spread of TBE are host population size, weather conditions, movement of hosts, and local regulations on the socioeconomic dynamics of the local and travelling people around the foci areas. The mean incidence rate of tick-borne encephalitis from 2000-2019 in Europe was 3.27, while the age-adjusted mean incidence rate was 2.19 per 100,000 population size. This review used several articles and data sources from the European Centre for Diseases Prevention and Control.
RESUMO
Tick-borne encephalitis (TBE) is a viral infection of the central nervous system (CNS) caused by tick-borne encephalitis virus (TBEV). It might take several clinical courses such as: meningitis, meningoencephalitis or meningoencephalomyelitis. The aim this study was to compare the YKL-40 concentration in cerebrospinal fluid (CSF) of patients with different clinical presentations of TBE and patients with excluded meningitis (control group). The concentration of YKL-40 in CSF was determined using Fujirebio tests (Ghent, Belgium) in 32 patients with TBE: Group I-patients with meningoencephalitis (n = 16); Group II-patients with meningitis (n = 16). The control group (CG) consisted of 17 patients in whom any inflammatory process in central nervous system was excluded. The concentration of YKL-40 was significantly higher in encephalitis group than in the CG after 7 days from the last dose of treatment. The concentration in patients with neuroinflammation had a significantly different concentration of YKL-40 compared to patients from the neuroinflammation control group. The ROC curve analysis indicates that CSF YKL-40 concentration at cut-off 783.87 differentiated TBE patients from CG with 100% specificity and 70% sensitivity and CSF YKL-40 concentration at cut-off 980.11 differentiated meningitis from meningoencephalitis with 87.5% specificity and 62.5% sensitivity. YKL-40 takes part in TBE pathogenesis, its concentration is the highest at the early stage of CNS involvement and decreases in the convalescent period. As YKL-40 was significantly higher in the meningitis than in the meningoencephalitis group, it might be used as biomarker in differentiation of these clinical forms of TBE.