NEUROLOGY AND PRECLINICAL NEUROLOGICAL STUDIES - ORIGINAL ARTICLE A distinct variant of mixed dysarthria reflects parkinsonism and dystonia due to ephedrone abuse Jan Rusz • Marika Megrelishvili • Cecilia Bonnet • Michael Okujava • Hana Broz ˇova ´ • Irine Khatiashvili • Madona Sekhniashvili • Marina Janelidze • Eduardo Tolosa • Evz ˇen Ru ˚z ˇic ˇka Received: 13 December 2013 / Accepted: 9 January 2014 Ó Springer-Verlag Wien 2014 Abstract A distinctive alteration of speech has been reported in patients suffering from ephedrone-induced parkinsonism. However, an objective assessment of dys- arthria has not been performed in ephedrone users. We studied 28 young Caucasian men from Georgia with a previous history of ephedrone abuse and compared them to 25 age-matched healthy controls. Speech examination, brain MRI, and NNIPPS-Parkinson plus scale were per- formed in all patients. The accurate differential diagnosis of dysarthria subtypes was based on the quantitative acoustic analyses of 15 speech dimensions. We revealed a distinct variant of mixed dysarthria with a combination of hyperkinetic and hypokinetic components representing the altered motor programming of dystonia and bradykinesia in ephedrone-induced parkinsonism. According to acoustic analyses, all patients presented at least one affected speech dimension, whereas dysarthria was moderate in 43 % and severe in 36 % of patients. Further findings indicated relationships between motor subscores of dystonia and bradykinesia and speech components of loudness (r = -0.54, p \ 0.01), articulation (r = 0.40, p \ 0.05), and timing (r =-0.53, p \ 0.01). In ephedrone-induced par- kinsonism a prominent mixed hyperkinetic–hypokinetic dysarthria occurs that appears related to marked dystonia and bradykinesia and probably reflects manganese induced toxic and neurodegenerative damage to the globus pallidus internus and substantia nigra. Keywords Speech disorder Á Dystonia Á Manganese Á Methcathinone Á Ephedrone Á Acoustic analysis Introduction Speech disorders that develop due to damage of nervous system, collectively termed dysarthria, can reflect under- lying neuropathology and their recognition may be valu- able to neurological localization and diagnosis (Darley et al. 1969; Duffy 2005). The occurrence of an atypical speech disorder has been noted in drug-addicted persons injecting an illicit psychostimulant known as ephedrone, which produces brain damage due to manganese toxicity Electronic supplementary material The online version of this article (doi:10.1007/s00702-014-1158-6) contains supplementary material, which is available to authorized users. J. Rusz Department of Circuit Theory, Faculty of Electrical Engineering, Czech Technical University in Prague, Prague, Czech Republic J. Rusz Á C. Bonnet Á H. Broz ˇova ´ Á E. Ru ˚z ˇic ˇka (&) Department of Neurology and Centre of Clinical Neuroscience, First Faculty of Medicine, Charles University in Prague, Prague, Czech Republic e-mail: eruzi@lf1.cuni.cz M. Megrelishvili Á M. Okujava Á I. Khatiashvili Institute of Medical Research, Ilia State University, Tbilisi, Georgia M. Megrelishvili Á I. Khatiashvili Á M. Sekhniashvili Á M. Janelidze Department of Neurology, S. Khechinashvili University Hospital, Tbilisi, Georgia M. Okujava Research Institute of Clinical Medicine, Tbilisi, Georgia E. Tolosa Neurology Service, Hospital Clı ´nic de Barcelona. Centro de Investigacio ´n Biome ´dica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Universitat de Barcelona, Barcelona, Spain 123 J Neural Transm DOI 10.1007/s00702-014-1158-6