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Objective Myoclonus Dystonia Syndrome (MDS) is a childhood onset, alcohol responsive movement disorder caused by mutations in the SGCE gene in a proportion of cases. Single family and case series have suggested co-morbid psychiatric disease but have not compared cases to a control group. Aims To establish a cohort of MDS patients with SGCE mutations and a control group of alcohol-responsive tremor patients, and to systematically assess for psychiatric symptoms using standardised questionnaires. Method We collected 27 patients with SGCE mutations and 45 tremor control cases. The MINI International Neuropsychiatric Interview, PHQ-9, MADRS, YBOCS and AUDIT were used to assess psychiatric disease according to DSM-IV criteria. Results There was a higher rate of psychiatric disease in MDS patients compared to controls (p Conclusion Overall psychiatric disease is elevated amongst the MDS cohort compared to a control group with a chronic, socially stigmatizing disorder. OCD appears to be the greatest contributor to this effect and may reflect a pleiotropic function for the SGCE gene.

L-dopa given to Parkinson9s disease (PD) patients for prolonged periods or at sustained high doses is known to produce disabling choreiform and dystonic dyskinesias. The production of dystonic dyskinesias at small doses in patients with deep brain stimulation surgery (DBS) has been poorly reported. We present a case series of 13 patients who tolerated high doses of l-dopa prior to DBS, who subsequently developed severe disabling dystonic dyskinesias on minimal doses of l-dopa after surgery. Of the 13 patients (7 male, 6 female), mean age was 54 (range 46–63), and mean disease duration was 10 years (range 6–17). 11 patients had presented with tremor as their first motor symptom of PD, and 10 had developed dyskinesias prior to surgery. At time of DBS the mean calculated L-dopa equivalent dose was 1073 mg (range 480–1566.7 mg) of which the mean l-dopa dose was 581 mg (range 300–1350 mg). The mean time from DBS to develop dystonic dyskinesias was 3 years (range 0.3–5 years), at which time the mean l-dopa equivalent dose was 366 mg (range 50–660 mg) and the mean l-dopa dose was 196 mg (range 50–600). Replacing l-dopa with a dopamine agonist either removed or largely relieved this motor complication. This case series highlights an important motor complication in the DBS PD patient and suggests one method to ameliorate it. It also raises important questions about the mechanism for reduction of dyskinesia threshold following DBS.

Subthalamic deep brain stimulation (STN DBS) for Parkinson9s disease typically enables a 50% reduction in dopaminergic medication postoperatively. This reduction in medication is accompanied by a 60% reduction in dyskinesia and a reduction in off periods. However, there remains a subgroup of patients who have disabling dyskinesias despite optimisation of drug and stimulator setting. Amantadine is sometimes used for the medical management of drug-induced dyskinesias in Parkinson9s disease. Its use in dyskinesias after DBS has not been formally assessed. We report a series of 8 cases who had bilateral STN DBS. These patients had similar characteristics to our local database of patients who have had DBS. However, these patients had disabling bradykinesia and/or dyskinesias despite attempts at optimisation of stimulator settings and dopaminergic medication. The addition of amantadine led to clear improvements in dsykinesias and/or mobility, without the need to increase the total dose of dopaminergic medication. Stopping amantadine caused worsening of symptoms. This case series suggests amantadine is an important additional medication in the small group of patients whose disease has not been stabilised after DBS. The outflow of the STN includes a glutamatergic pathway. The glutamate receptor blocking properties of amantadine provide a possible mechanism for the observed benefit. We plan to extend the results of this case series to include objective scoring in subsequent patients.

Background A number of epidemiologic studies show a decreased risk of non-melanoma cancer in Parkinson9s disease (PD). Cigarette smoking is less prevalent in PD and hence the risk of smoking related neoplasia such as lung and colon would be expected to be decreased in PD. A link is shown between decreased physical activity and colorectal cancer. Increased dietary intake of iron increases colorectal cancer risk and iron deposition in the basal ganglia is a feature of PD. Thus common mechanisms may be involved in both disorders. Our study looks at a cohort of surgically treated PD patients to see if there is an altered risk of colorectal cancer among them. Method In our population of patients fitted with a deep brain stimulator between 2002 and 2010, we searched for causes of death confirmed against death certificates and a histological diagnosis of colorectal cancer in the patient records. Results Of 22 patients who had died, 3 had a diagnosis colorectal cancer. 1 more died of a carcinoembryonic antigen positive cancer of unknown origin. Discussion From UK national statistics, colorectal cancer accounts for between 2.7 and 3.2% of all deaths. Although the small number of deaths in our cohort requires careful interpretation of the results, 14% of our cohort having a diagnosis of colorectal cancer suggests that the lifetime risk of colorectal cancer is not reduced in PD patients. This observation merits further investigation in a larger cohort of PD patients.