Magnetic resonance imaging and clinical findings in adults with tick-borne encephalitis.
BACKGROUND
Magnetic resonance imaging (MRI) in tick-borne encephalitis (TBE) is often performed for differential diagnosis, but only a few reports on the morphologic changes in TBE patients and their relation to the disease severity exist.


METHODS
We retrospectively searched for all TBE patients who were admitted to the Departments of Neurology of the Medical University of Graz (Austria) and the Paracelsus Medical University of Salzburg (Austria) between 2003 and 2014. We recorded the clinical and demographic variables and rated overall disease severity as mild, moderate, severe or leading to death due to TBE. MRI scans were screened for morphologic abnormalities.


RESULTS
Of an initial cohort of 88 patients with TBE, 45 patients with an available MRI of the brain were included in this study (median age 58.0years, range: 18-80; men n=28). Their median time spent in the hospital was 18days (range: 4-174days). 16 patients had a mild, 18 a moderate and 10 a severe disease course. One patient died due to TBE. TBE related brain abnormalities could be identified in 4 cases. They consisted of diffuse areas of T2-signal hyperintensity, which were located in the crura cerebri in three patients and in the right centrum semiovale in one patient. No contrast enhancement was observed in any of the lesions and their presence was not related to specific clinical findings or the severity of TBE.


CONCLUSIONS
MRI brain lesions in TBE are rare and do not correlate with the course of the disease. Diffuse areas of signal hyperintensity in the crura cerebri appear suggestive of TBE.
Department of Neurology, Medical University of Graz, Auenbruggerplatz 22, 8036 Graz, Austria. Electronic address: alexander.pichler@medunigraz.at.
Alexander
A
Pichler
Department of Neurology, Paracelsus Medical University of Salzburg, Ignaz-Harrer-Straße 79, 5020 Salzburg, Austria.
Johann
J
Sellner
Department of Neurology, Paracelsus Medical University of Salzburg, Ignaz-Harrer-Straße 79, 5020 Salzburg, Austria.
Gayane
G
Harutyunyan
Department of Pediatrics and Adolescent Medicine, Medical University Graz, Auenbruggerplatz 34/2, 8036 Graz, Austria.
Astrid
A
Sonnleitner
Department of Pediatrics and Adolescent Medicine, Medical University Graz, Auenbruggerplatz 34/2, 8036 Graz, Austria.
Daniela Sabine
DS
Klobassa
Department of Neurology, Medical University of Graz, Auenbruggerplatz 22, 8036 Graz, Austria.
Juan-Jose
JJ
Archelos-Garcia
Department of Neurology, Medical University of Graz, Auenbruggerplatz 22, 8036 Graz, Austria.
Hannah
H
Rock
Department of Neurology, Medical University of Graz, Auenbruggerplatz 22, 8036 Graz, Austria.
Thomas
T
Gattringer
Department of Neurology, Medical University of Graz, Auenbruggerplatz 22, 8036 Graz, Austria.
Franz
F
Fazekas
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D001921:Brain / Q000000981:diagnostic imaging*; D004185:Disability Evaluation; D004675:Encephalitis, Tick-Borne / Q000000981:diagnostic imaging* / Q000473:pathology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012720:Severity of Illness Index; D055815:Young Adult
Brain lesions; Disease severity; Magnetic resonance imaging (MRI); Tick-borne encephalitis (TBE)