Related Experiment Video
Updated: Jan 4, 2026
Functional Neuroimaging Using Ultrasonic Blood-brain Barrier Disruption and Manganese-enhanced MRI
Published on: July 12, 2012
Cognitive profile of patients with manganese-methcathinone encephalopathy
Margus Ennok1, Katrin Sikk2, Sulev Haldre1
1Department of Neurology and Neurosurgery, Institute of Clinical Medicine, University of Tartu, L. Puusepa 8, 50406 Tartu, Estonia; Neurology Clinic, Tartu University Hospital, L. Puusepa 8, 50406 Tartu, Estonia.
Abstract:
Manganese-methcathinone encephalopathy (MME) is a rare parkinsonian syndrome described in drug addicts who have self-injected a home-made mixture containing methcathinone and manganese. We assessed 14 patients with MME and compared their results with 14 matched control subjects. The patients had a parkinsonian syndrome with symmetrical bradykinesia, dystonias, and postural, gait and speech impairment, with moderate restrictions in activities of daily living. Their cognitive status was assessed with the Russian version of the Wechsler Adult Intelligence Scale (WAIS) and with tests of attention (Trail Making Test, Bourdon-Wiersma Dot Cancellation Test), memory (Auditory Verbal Learning Test, Rey-Osterrieth Complex Figure), motor skills (Grooved Pegboard), visuospatial skills (Money Road Map Test, Benton Judgment of Line Orientation), and executive abilities (Verbal Fluency, 5-Point Test, Wisconsin Card Sorting Test). Only a few significant differences emerged. After controlling for multiple comparisons, the results in the WAIS Object Assembly subtest, the Grooved Pegboard test (dominant and nondominant hand) and the Verbal Fluency test remained significant.
Insights
Manganese-methcathinone encephalopathy (MME) is a rare parkinsonian syndrome. Cognitive and motor assessments revealed significant deficits in object assembly, manual dexterity, and verbal fluency in MME patients.
Area of Science:
- Neuroscience
- Toxicology
- Neurology
Background:
- Manganese-methcathinone encephalopathy (MME) is a rare parkinsonian syndrome.
- It is associated with the self-injection of illicit drugs containing methcathinone and manganese.
- MME presents with parkinsonian symptoms and potential cognitive impairments.
Purpose of the Study:
- To assess the cognitive and motor deficits in patients with MME.
- To compare the performance of MME patients with matched control subjects.
- To identify specific areas of impairment in MME.
Main Methods:
- 14 patients with MME and 14 matched controls were assessed.
- Cognitive function was evaluated using the Russian Wechsler Adult Intelligence Scale (WAIS).
- Specific tests were used for attention, memory, motor skills, visuospatial abilities, and executive functions.
Main Results:
- MME patients exhibited parkinsonian features including bradykinesia, dystonia, and impaired gait and speech.
- Significant differences between MME patients and controls were found in WAIS Object Assembly, Grooved Pegboard (both hands), and Verbal Fluency tests after controlling for multiple comparisons.
- Overall, moderate restrictions in daily living activities were observed.
Conclusions:
- Manganese-methcathinone encephalopathy leads to a distinct parkinsonian syndrome with specific cognitive and motor deficits.
- Impairments in executive functions (Verbal Fluency) and fine motor skills (Grooved Pegboard) are characteristic of MME.
- Further research is needed to understand the long-term neurological consequences of MME.
