Bogovič P, et al.
Cerebrospinal fluid findings and their temporal pattern in patients with different clinical presentations of tick-borne encephalitis: a cohort study. Infection. Published online November 27, 2025. doi:10.1007/s15010-025-02700-y
There is still a lack of systematic data on cerebrospinal fluid (CSF) findings across different clinical manifestations of tick-borne encephalitis (TBE) and according to the duration of neurological involvement. A study was conducted in 717 Slovenian patients with TBE to evaluate and compare routine CSF findings among patients with the three clinical forms—meningitis (M), meningoencephalitis (ME), and meningoencephalomyelitis (MEM)—and to gain insights into the temporal dynamics of CSF changes during the first 10 days after the onset of neurological symptoms.
Among the 717 patients with TBE, 32.1% presented with M, 62.6% with ME, and 5.7% with MEM. Patients with M were significantly younger than those with ME or MEM. There were no statistically significant differences in sex distribution among the M, ME, and MEM groups, nor in the proportion of patients with a biphasic disease course.
Among the 15 routinely measured CSF parameters, significant or clinically relevant differences were observed across the three clinical groups. Notable differences were found in CSF leukocyte count, neutrophil proportion, glucose concentration, total protein and albumin levels, concentrations of IgM, IgG, and IgA, as well as albumin and immunoglobulin indices. Overall, CSF abnormalities were most pronounced in the MEM group and least pronounced in patients with M, indicating that the clinical manifestations of TBE are associated with distinct CSF profiles. These alterations appeared early, peaked within the first few days, and then stabilized or improved, although this pattern was less predictable in MEM.