["Ephedron" encephalopathy].

The results of clinical, neuropsychological and MRI study of 21 patients with "ephedron" encephalopathy caused by intake of methcatinon ("ephedron"), a surrogate drug obtained from phenylpropanolamine-containing compounds by adding potassium permanganate, are presented. Signs of brain lesions emerged 3-14 (mean 6.8 +/- 4.9) months after the beginning of the regular drug intake. Neurological disturbances were measured using the Scale of clinical assessment of ephedron encephalopathy. In the acute stage of the disease, most patients had the combination of extrapyramidal disorders (parkinsonism, muscular dystonia, tremor, myoclonia) with pronounced postural instability, pseudobulbar syndrome, autonomic, cognitive and affective personality abnormalities of subcortical and frontal types. In 18 (86%) patients, MRI revealed a bilateral symmetric elevation of the signal from the basal ganglia on T1-weighted images, mostly from the medial segment of globus pallidus and the reticular part of substantia nigra that reflected magnesium accumulation. The spread of hyperintensive MRI changes negatively correlated with the disease duration (r = -0.6; p < 0.01), but did not depend on the drug abuse duration or its approximate total dosage, and also did not correspond to the disease severity. In follow-up, a tendency to spontaneous regress of symptoms was observed in 29% of the cases, and in 33% patients symptoms have been regressing even 4 years after stopping of methcatinon intake. The main mechanisms of "ephedron" encephalopathy development are probably related to the manganese accumulation in the brain that might trigger secondary pathogenetic mechanisms, such as mitochondrial dysfunction, oxidative stress, etc. The induction courses of calcium and sodium EDTA that accelerates manganese excretion decrease a probability of the further disease progress, though do not contribute significantly to symptoms regress. The data on possibilities of symptomatic therapy of movement and affective disturbances is presented.