Kelly Bertram

Visual hallucinations in the differential diagnosis of parkinsonism

Visual hallucinations (VH) occur commonly in Parkinsons disease (PD) and dementia with Lewy bodies (DLB) but are reported much less frequently in other neurodegenerative causes of parkinsonism, such as progressive supranuclear palsy, multiple system atrophy and corticobasal degeneration syndrome. This clinical sign may be helpful when considering the differential diagnosis of patients with parkinsonism. The observation that VH may be specific to Lewy body pathology probably reflects a greater vulnerability of the visual systems to PD and DLB neurodegeneration compared with other diseases. Topographic differences in pathology are probably the major factor producing VH in Lewy body diseases, rather than neurophysiological changes that are specific to α-synuclein protein accumulation. VH correlate with pathology in the limbic system and more specifically the amygdale that is frequently affected in PD and DLB but relatively preserved in other forms of parkinsonism often misdiagnosed as PD. In this review, the published frequencies of VH in these different conditions are compared to put into context the notion of VH as a clinical clue to underlying Lewy body pathology.

Sex differences in Parkinson's disease.

Sex-related differences in Parkinsons disease (PD) have been recognised, but remain poorly understood. We aimed to further clarify real-life differences in disease experience according to sex, by evaluating quality of life (QoL), demographic and clinical characteristics of PD patients. A cross-sectional survey was conducted on 210 PD patients (129 men, 81 women) attending specialist neurological clinics across three centres. Outcome measures included the motor examination of the Unified Parkinsons Disease Rating Scale (UPDRS-III) and QoL as measured by the 39-item Parkinsons Disease Questionnaire (PDQ-39). A male to female ratio of 1.6:1 was observed. Men reported a greater disease burden than women as noted by higher UPDRS-III scores (27 ± 13 versus 23 ± 13, p=0.032), daily levodopa equivalent doses (898.1 ± 481.3mg versus 750.7 ± 427.2mg, p=0.037) and caregiver reliance (44% versus 29.5%, p=0.039). The UPDRS-III score was significantly associated with sex after controlling for age and disease duration, with men more severely affected (β=-0.165, r(2)=0.101, p=0.028). The PDQ-39 showed men reported lower QoL in activities of daily living (ADL), cognition and communication sub-scales (p<0.05). An association was identified in men between PDQ-39 ADL and cognition sub-scales (r=0.660, p<0.001). Men with an appointed caregiver had a higher PDQ-39 Summary Index (t=3.222, degrees of freedom=122, p=0.002). PD was found to have greater overall impact on the health and well-being of male patients in sub-specialty clinical practice. Our study further supports the need for increased sex-delineated clinical assessment and consideration of potential differences required in the management of PD.

Short and long term outcome of bilateral pallidal stimulation in chorea-acanthocytosis

Background Chorea-acanthocytosis (ChAc) is a neuroacanthocytosis syndrome presenting with severe movement disorders poorly responsive to drug therapy. Case reports suggest that bilateral deep brain stimulation (DBS) of the ventro-postero-lateral internal globus pallidus (GPi) may benefit these patients. To explore this issue, the present multicentre (n=12) retrospective study collected the short and long term outcome of 15 patients who underwent DBS. Methods Data were collected in a standardized way 2-6 months preoperatively, 1-5 months (early) and 6 months or more (late) after surgery at the last follow-up visit (mean follow-up: 29.5 months). Results Motor severity, assessed by the Unified Huntington’s Disease Rating Scale-Motor Score, UHDRS-MS), was significantly reduced at both early and late post-surgery time points (mean improvement 54.3% and 44.1%, respectively). Functional capacity (UHDRS-Functional Capacity Score) was also significantly improved at both post-surgery time points (mean 75.5% and 73.3%, respectively), whereas incapacity (UHDRS-Independence Score) improvement reached significance at early post-surgery only (mean 37.3%). Long term significant improvement of motor symptom severity (≥20 % from baseline) was observed in 61.5 % of the patients. Chorea and dystonia improved, whereas effects on dysarthria and swallowing were variable. Parkinsonism did not improve. Linear regression analysis showed that preoperative motor severity predicted motor improvement at both post-surgery time points. The most serious adverse event was device infection and cerebral abscess, and one patient died suddenly of unclear cause, 4 years after surgery. Conclusion This study shows that bilateral DBS of the GPi effectively reduces the severity of drug-resistant hyperkinetic movement disorders such as present in ChAc.

Influence of Single Nucleotide Polymorphisms in COMT, MAO-A and BDNF Genes on Dyskinesias and Levodopa Use in Parkinson’s Disease

Background: Clinical heterogeneity in the development of levodopa-induced dyskinesias (LID) suggests endogenous factors play a significant role in determining their overall prevalence. Objective: We hypothesised that single nucleotide polymorphisms (SNPs) in specific genes may result in a clinical phenotype conducive to an increased risk of LID. Methods: We examined the influence of SNPs in the catechol-O-methyltransferase (COMT), monoamine oxidase A (MAO-A) and brain-derived neurotrophic factor (BDNF) genes on LID in a cohort of 285 pathologically confirmed Parkinsons disease patients, using data from their complete disease course. Results: Dyskinetic patients demonstrated younger age at disease onset (60.3 vs. 66.4 years, p < 0.0001), a longer disease duration (17.0 vs. 12.0 years, p < 0.0001) and a higher maximum daily levodopa equivalent dose (LED; 926.7 vs. 617.1 mg/day, p < 0.0001) than patients without dyskinesias. No individual SNP was found to influence prevalence or time to onset of dyskinesias, including after adjustment for known risk factors. We observed that patients carrying alleles conferring both high COMT activity and increased MAO-A mRNA expression received significantly higher maximum and mean daily LEDs than those with low enzyme activity/mRNA expression (max LED: 835 ± 445 vs. 508 ± 316 mg; p = 0.0056, mean LED: 601 ± 335 vs. 398 ± 260 mg; p = 0.025). Conclusions: Individual SNPs in BDNF, COMT and MAO-A genes did not influence prevalence or time to onset of dyskinesias in this cohort. The possibility that combined COMT and MAO-A genotype is a significant factor in determining an individuals lifetime levodopa exposure warrants further investigation.

Serotonergic Markers in Parkinson's Disease and Levodopa-Induced dyskinesias

Preclinical animal models implicate serotonin neurons in the pathophysiology of levodopa (l‐dopa)–induced dyskinesias in Parkinsons disease (PD), but effective treatment remains elusive. We examined the relationship between serotonin and l‐dopa–induced dyskinesias in a pathologically confirmed cohort of PD patients. We obtained brain tissue from 44 PD cases and 17 age‐matched controls and assessed monoamine levels and the serotonin and dopamine transporters in the striatum, and the extent of dopaminergic and serotonergic cell preservation in the substantia nigra (SN) and the dorsal raphe nuclei (DRN), respectively. As expected, PD patients demonstrated a severe loss of all dopaminergic markers, including dopamine (P < 0.0001) and the dopamine transporter (P < 0.0001) in the striatum, and dopaminergic neurons (P < 0.001) in the SN, compared with controls. Marked serotonin loss was observed in the caudate (but not putamen) in PD patients compared with controls (P < 0.001), but no difference was found in the levels of the serotonin transporter in the striatum or density of serotonergic neurons in the DRN between these groups, suggesting a functional but not structural change in the serotonergic system in PD. No difference was seen in levels of serotonergic and dopaminergic markers in the striatum between PD patients with and without dyskinesias, or between cases separated according to the clinical severity of their dyskinesias. The absence of a correlation between striatal serotonin markers and the incidence and severity of l‐dopa–induced dyskinesias suggests that an intact and functioning serotonergic system is not a risk factor for developing dyskinesias in PD.

Safety and efficacy of botulinum toxin in primary orthostatic tremor.

Primary orthostatic tremor (POT) is a rapid 13-18 Hertz tremor that produces a subjective feeling of unsteadiness when standing, and is absent when seated or supine. It predominantly affects the legs during isometric contraction though a similar tremor can be seen in the arms and jaw. When present in the jaw this rapid tremor has been successfully treated with botulinum toxin. We sought to test whether symptoms of POT improved following injection of abobotulinumtoxinA to muscles in the legs. This randomised, double blind, placebo controlled cross-over design study enrolled eight patients with electrophysiologically confirmed POT. Each patient received injections of either 200 mU abobotulinumtoxinA or 0.9% saline in the tibialis anterior bilaterally, with cross-over after 20 weeks. Electrophysiological and clinical assessments were performed before and 6 weeks after each injection. Seven patients completed the study. No significant differences were seen in the primary outcome measures of time from standing to unsteadiness or symptom diary scores. Electrophysiological characteristics of POT remained remarkably constant throughout the study in all patients with variability of less than 1 Hertz in the frequency recorded. Falls were common, with one patient experiencing a fall with upper limb fracture whilst on the placebo. The frequency of falls correlated with both the severity of the self-rated symptoms and a shorter time to feeling unsteady with eyes closed. In conclusion, treatment with 200 mU of abobotulinumtoxinA in the tibialis anterior does not alter subjective experience of unsteadiness in POT. Postural instability and falls are common.

Diagnosis of dystonic syndromes—a new eight-question approach

Dystonia is a syndrome of abnormal involuntary movements that are repetitive, twisting or patterned, and can result in abnormal postures. Dystonia may be generalized or focal, and can occur as a primary syndrome or secondary to another disease—over 50 clinical conditions are reported to cause dystonia. Classification of dystonia is based on genetic background, anatomical distribution, age at onset, and neurodegenerative processes. In many cases, manifestations of dystonia are identical regardless of the aetiology, which makes accurate diagnosis challenging, if not impossible, without additional investigations. Exhaustive lists of the causes of dystonia are not practical to aid clinicians when attempting to determine if a hyperkinetic movement can be diagnosed as dystonic. The existing diagnostic algorithms for dystonic syndromes rely on the clinicians experience, without a streamlined diagnostic pathway. Non-specialist clinicians and neurologists may, therefore, find diagnosis of dystonic syndromes difficult. In this Review, an eight-question approach is proposed, with a summary of the evidence for investigations that enable successful diagnosis of dystonic syndromes. The aim of this approach is to inform both specialists and general neurologists on the appropriate diagnostic test for each patient who presents with a possible dystonic syndrome.

Treatment of camptocormia with botulinum toxin

Camptocormia is defined as an involuntary axial postural distortion of >45° flexion which occurs in the upright position, increases whilst walking and resolves when supine (Ashour and Jankovic, 2006). Unlike orthopaedic or age related kyphosis it is not a fixed structural deformity and produces kyphosis at predominantly lumbar and thoracic rather than cervical regions. Camptocormia has been reported due to a wide range of neurologic, psychiatric, muscular and orthopaedic conditions as well as rare reports of its emergence following the initiation of a number of medications (Finsterer and Strobl, 2010). Parkinsons disease (PD) includes prominent motor features of bradykinesia, rigidity and reduced postural balance responses in all those affected with this disease, but can also cause a range of other motor and non-motor features. Camptocormia is reported in a minority of patients with PD, and it is usually associated with longer disease duration and greater disease burden (Tiple et al., 2009). The aetiology of camptocormia in PD is debated, and responses to treatment have been generally poor and variable between studies. Recent studies have suggested the use of botulinum toxin may improve posture in some affected individuals.

A cross-sectional study of clinical management, and provision of health services and their utilisation, by patients with Parkinson's disease in urban and regional Victoria.

Our objective was to evaluate and compare clinical management, utilisation of health services and quality of life (QoL) in patients with Parkinsons disease (PD) attending clinics in urban and regional Victoria. A cross-sectional survey was conducted on 210 patients with PD attending specialist neurological clinics in a regional area (Ballarat) (n=97), and an urban area (Melbourne) (n=113), Victoria. Demographic characteristics of patients with PD, QoL, patterns of disease and management and utilisation of medical and allied health services were analysed. Compared to patients with PD from urban clinics, patients in the regional clinic were significantly older and were diagnosed at a later age with a shorter duration of treatment (all p<0.05). Despite no significant difference in disease severity (measured by Unified Parkinsons Disease Rating Scale scores) between the groups, patients in the urban clinic reported a lower QoL (p=0.003). Patients in the regional clinic were more satisfied with their treatment, despite seeing their medical specialist less frequently (p<0.001) and having a higher rate of early misdiagnosis (p=0.015). Patients from regional clinics reported a poorer understanding of their illness than patients in the urban clinic (p=0.049). Half of all respondents were interested in using telemedicine services. Two-thirds (71%) of all patients used allied health services, with patients in the urban clinic utilising more and desiring greater access to these services (p<0.05). In conclusion, we found significant differences in the presentation, management and use of health services between patients accessing regional and urban PD clinics in Victoria. Telemedicine may be an effective, and even desirable, method for facilitating improved diagnosis and referral for appropriate therapies.

Delays to the diagnosis of cervical dystonia.

The diagnosis of cervical dystonia (CD) is based on physical examination and is therefore reliant on clinician experience. Due to variability of presenting symptoms it may be misdiagnosed, thus delaying the provision of effective treatment. We sought to determine the average time taken to make a diagnosis of CD in our clinical cohort and explore contributing factors to diagnostic delay. Forty-nine patients with a diagnosis of CD attending a movement disorder specialist for treatment completed a questionnaire regarding symptoms and clinical interactions at onset and diagnosis. The mean time from symptom onset to diagnosis was 6.8 years (range 0-53 years). More than 50% of patients sought physical therapies initially, prior to consulting their general practitioner. Only 40% of patients sought medical advice within the first 6 months of symptom onset and only 10% were given an initial diagnosis of CD. The first referral from the general practitioner was to a specialist other than a neurologist in 31% of patients. Patients were seen by a mean of three doctors (range one to nine) before being given the correct diagnosis of CD. Delay to diagnosis of CD may in part be due to lack of awareness of the condition amongst health care professionals. Improved diagnostic skill appears likely to have had a substantial impact on the delivery of appropriate treatment in this population.