Cerebellar presentation of multiple system atrophy

Early diagnosis of multiple-system atrophy (MSA) is important in patients presenting with late-onset cerebellar ataxia because it has a less favourable prognosis than other degenerative ataxic disorders. We report cerebellar presentation of MSA in a series of 16 patients, 3 of whom later developed parkinsonism. Two-thirds of them had early evidence of impaired postural reflexes with a history of recurrent falls. Some of these had a narrow-based, unsteady gait, unlike the more classic broad-based gait ataxia of cerebellar disease. On review of the patients' histories, genitourinary dysfunction (particularly impotence) was present at the onset of, or preceding, cerebellar ataxia in 60% of patients, but this had often been attributed to age, or to urological or gynaecological causes. External striated anal or urethral sphincter electromyography (EMG) demonstrated features of chronic denervation and reinnervation in 14 (93%) of 15 patients, consistent with degeneration in Onuf's nucleus as occurs in MSA. Autonomic function tests were abnormal in 9 (64%) of 14 patients. Our data suggest that close enquiry into genitourinary function and analysis of the gait disorder can be useful pointers to a diagnosis of MSA in patients with an unexplained adult-onset progressive cerebellar syndrome, and that sphincter EMG is the most useful investigation in this context.

Associative learning in patients with cerebellar ataxia

It has been claimed that patients with cerebellar pathology are impaired at associative learning. Patients with cerebellar ataxia (n = 7) were taught a visual-motor associative task. The task was chosen so as to allow comparisons with data currently being collected on the effects of cerebellar lesions on associative learning in monkeys. As a group the patients were as impaired at learning the task as a group of 8 patients with Huntington's disease. When each patient was individually matched with a control of the same age and IQ, some patients with cerebellar ataxia were found to be clearly impaired, but 2 were not. Of the 4 patients who were most clearly impaired, 2 had brainstem pathology and 2 did not. The relevance of these findings is discussed in relation to views concerning the functions of the cerebellum.

Clinical drug monitoring by microdialysis: application to levodopa therapy in Parkinson's disease

1. We describe the first application of microdialysis to monitor the pharmacokinetics of a drug in the blood of man. 2. The aims of the study were to ascertain patient acceptability and tolerability of a new microdialysis probe and to assess its accuracy in determining the pharmacokinetics of levodopa and its principal plasma metabolite 3-O-methyldopa (3-OMD). 3. Eight patients with parkinsonism on chronic levodopa therapy were investigated. 4. After an overnight fast, a flexible microdialysis probe, perfused with isotonic saline, was inserted into a forearm vein and a blood sampling cannula was inserted in a forearm vein of the other arm. After ingestion of a levodopa preparation (Madopar Dispersible), dialysate was collected over 5 or 10 min periods and blood samples were taken every 15 or 30 min for 2-6 h. 5. Dialysate drug profiles were similar to those of plasma, and levodopa and 3-OMD concentrations exhibited significant (P < 0.001) correlation with those observed in the corresponding plasma samples. 6. The mean (+/- s.d.) blood dialysate concentrations for levodopa and 3-OMD were 36.1 +/- 9.2% and 43.4 +/- 8.4% respectively of the plasma content. 7. The tolerability of the probe was excellent, and all eight patients found it preferable to conventional blood sampling. 8. Microdialysis of blood is less invasive than frequent intermittent direct blood sampling, and can readily be used to continuously monitor levodopa pharmacokinetics. In a clinical setting, a combination of drug monitoring by this technique together with clinical evaluation of motor function can be used to optimize levodopa treatment in patients with Parkinson's disease.

Consensus guidelines for the clinical and pathologic diagnosis of dementia with Lewy bodies (DLB): report of the consortium on DLB international workshop

Recent neuropathologic autopsy studies found that 15 to 25% of elderly demented patients have Lewy bodies (LB) in their brainstem and cortex, and in hospital series this may constitute the most common pathologic subgroup after pure Alzheimer's disease (AD). The Consortium on Dementia with Lewy bodies met to establish consensus guidelines for the clinical diagnosis of dementia with Lewy bodies (DLB) and to establish a common framework for the assessment and characterization of pathologic lesions at autopsy. The importance of accurate antemortem diagnosis of DLB includes a characteristic and often rapidly progressive clinical syndrome, a need for particular caution with neuroleptic medication, and the possibility that DLB patients may be particularly responsive to cholinesterase inhibitors. We identified progressive disabling mental impairment progressing to dementia as the central feature of DLB. Attentional impairments and disproportionate problem solving and visuospatial difficulties are often early and prominent. Fluctuation in cognitive function, persistent well-formed visual hallucinations, and spontaneous motor features of parkinsonism are core features with diagnostic significance in discriminating DLB from AD and other dementias. Appropriate clinical methods for eliciting these key symptoms are described. Brainstem or cortical LB are the only features considered essential for a pathologic diagnosis of DLB, although Lewy-related neurites, Alzheimer pathology, and spongiform change may also be seen. We identified optimal staining methods for each of these and devised a protocol for the evaluation of cortical LB frequency based on a brain sampling procedure consistent with CERAD. This allows cases to be classified into brainstem predominant, limbic (transitional), and neocortical subtypes, using a simple scoring system based on the relative distribution of semiquantitative LB counts. Alzheimer pathology is also frequently present in DLB, usually as diffuse or neuritic plaques, neocortical neurofibrillary tangles being much less common. The precise nosological relationship between DLB and AD remains uncertain, as does that between DLB and patients with Parkinson's disease who subsequently develop neuropsychiatric features. Finally, we recommend procedures for the selective sampling and storage of frozen tissue for a variety of neurochemical assays, which together with developments in molecular genetics, should assist future refinements of diagnosis and classification.

Reversal of behavioural abnormalities by fetal allografts in a novel rat model of striatonigral degeneration

We have developed a rodent model of striatonigral degeneration, one of the core pathologies underlying the disease multiple system atrophy (MSA). 6-Hydroxydopamine (6-OHDA) was administered into the left medial forebrain bundle of male Wistar rats, followed 3-4 weeks later by intrastriatal injection of quinolinic acid into the ipsilateral striatum. The 6-OHDA lesion resulted in ipsilateral rotation to (+)-amphetamine and contralateral rotation to apomorphine. Following the subsequent striatal lesion, amphetamine-induced ipsilateral rotation persisted, but apomorphine-induced contralateral rotation was reduced or abolished. Subsequently, the lesioned striatum was implanted with fetal CNS allografts consisting of cell suspensions derived from striatal primordium alone or combined with cografts of ventral mesencephalon. Cografted rats showed a reduction or reversal of amphetamine-induced rotation. This was not observed in animals receiving striatal grafts alone. Apomorphine-induced contralateral rotation was restored after striatal grafts alone, but only partially in animals receiving sham or cografts. Tyrosine hydroxylase (TH) and dopamine- and cyclic adenosine 3':5'-monophosphate-regulated phosphoprotein (DARPP 32) immunocytochemistry showed mesencephalic and striatal graft survival in most animals. However, dopaminergic outgrowth was restricted to the graft deposit. The latter was surrounded by a markedly gliotic glial fibrillary acidic protein-positive capsule continuous with corpus callosum. Dopaminergic reinnervation of denervated and lesioned adult striatum itself was absent, suggesting that rotational recovery was due to diffuse dopamine release. The study shows that combined unilateral lesioning of rodent medial forebrain bundle and striatum results in a characteristic drug-induced rotational response that can be partly restored by mesencephalic/striatal cografts.

Clinical research criteria for the diagnosis of progressive supranuclear palsy (Steele-Richardson-Olszewski syndrome): report of the NINDS-SPSP international workshop

To improve the specificity and sensitivity of the clinical diagnosis of progressive supranuclear palsy (PSP, Steele-Richardson-Olszewski syndrome), the National Institute of Neurological Disorders and Stroke (NINDS) and the Society for PSP, Inc. (SPSP) sponsored an international workshop to develop an accurate and universally accepted set of criteria for this disorder. The NINDS-SPSP criteria, which were formulated from an extensive review of the literature, comparison with other previously published sets of criteria, and the consensus of experts, were validated on a clinical data set from autopsy-confirmed cases of PSP. The criteria specify three degrees of diagnostic certainty: possible PSP, probable PSP, and definite PSP. Possible PSP requires the presence of a gradually progressive disorder with onset at age 40 or later, either vertical supranuclear gaze palsy or both slowing of vertical saccades and prominent postural instability with falls in the first year of onset, as well as no evidence of other diseases that could explain these features. Probable PSP requires vertical supranuclear gaze palsy, prominent postural instability, and falls in the first year of onset, as well as the other features of possible PSP. Definite PSP requires a history of probable or possible PSP and histopathologic evidence of typical PSP. Criteria that support the diagnosis of PSP, and that exclude diseases often confused with PSP, are presented. The criteria for probable PSP are highly specific, making them suitable for therapeutic, analytic epidemiologic, and biologic studies, but not very sensitive. The criteria for possible PSP are substantially sensitive, making them suitable for descriptive epidemiologic studies, but less specific. An appendix provides guidelines for diagnosing and monitoring clinical disability in PSP.

Ataxia without telangiectasia masquerading as benign hereditary chorea

We report a nonconsanguineous family in whom two (of three) sons developed isolated chorea in early childhood, suggesting a diagnosis of benign hereditary chorea (BHC). However, cerebellar ataxia and oculomotor apraxia, without telangiectasia, subsequently developed. Chromosome analysis showed increased radiosensitivity in both brothers and translocations in the younger one. We conclude that ataxia with chromosomal instability may masquerade as BHC in some patients.

Olivopontocerebellar pathology in multiple system atrophy

Olivopontocerebellar atrophy (OPCA) is widely accepted as part of the neuropathological spectrum of multiple system atrophy (MSA). The distribution of affected sites in the olivopontocerebellar (OPC) system and their interrelationship remain poorly understood due to lack of quantitative studies. To further investigate the OPC pathology in MSA, we performed a morphometric analysis of 20 MSA cases and eight healthy controls. In the MSA cases, mean neuronal cell densities were significantly reduced in (medial and dorsal) accessory and principal inferior olives, pontine nuclei, cerebellar vermis (except nodulus), and hemispheres. Inferior olives and pontine nuclei were more severely affected than cerebellar Purkinje cells in most cases. Cerebellar Purkinje cells were more severely depleted in vermis rather than in hemisphere. There was a poor topographic correlation between neuronal cell loss in inferior olives and cerebellar cortex. These results suggest a primary degeneration of olivopontine nuclei and cerebellar Purkinje cells in OPCA. Inferior olives, pontine nuclei and cerebellar cortex were all significantly more severely affected in cases with a pure or predominating cerebellar syndrome (OPCA type, n = 4) compared to those with pure or predominating parkinsonism (SND type, n = 14). However, although cerebellar signs had been noted in life in only six cases, morphometry revealed OPCA in 17 of the 20 MSA brains.

Essential myoclonus and myoclonic dystonia

This review explores the history and use of the terms essential myoclonus and myoclonic dystonia. In addition, the review proposes that hereditary essential myoclonus and dominantly inherited myoclonic dystonia, with lightning jerks and dramatic response to alcohol, are the same disease, although proof of this hypothesis must come from ongoing genetic studies.

Pain in multiple system atrophy

Pain is a recognized feature of idiopathic Parkinson's disease (IPD) but has never been studied in multiple system atrophy (MSA), the commonest cause of atypical parkinsonism. We retrospectively analysed histories of pain in 100 consecutive cases of clinically probable MSA. Details were obtained from the medical records of 100 patients with MSA, comprising 82 with the striatonigral degeneration (SND) type and 18 with the olivopontocerebellar atrophy (OPCA) type of MSA. Pain was reported in 47% of the MSA patients. It was classified as rheumatic in 64% of MSA patients reporting pain, sensory in 28%, dystonic in 21%, and levodopa-related in 16%, mostly related to off-period or diphasic dystonias. There was a mixed pain syndrome in 19% of these patients. Pain was significantly more commonly reported by females (P = 0.02), and by patients with levodopa-induced dyskinesias (P = 0.02). No other clinical feature differentiated MSA patients who reported pain from those who did not. The mean delay between disease onset and onset of pain was 2.9 years, but pain was reported at the time of, or before, disease onset in about 30% of patients. The overall prevalence of pain in MSA was similar to that reported in IPD, but the distribution of pain categories was different.

Strength in Parkinson's disease: relationship to rate of force generation and clinical status

Maximum elbow flexor and extensor muscle strength was measured in 9 patients with Parkinson's disease on and off antiparkinsonian medication. In addition, the rate of force generation, the rate of actively returning force to resting levels, and passive release of force "relaxation" were measured in submaximal contractions. The measures of strength and contraction time were correlated with changes in clinical status as measured by the Unified Parkinson's Disease Rating Scale. When patients were off medication, their reduction in strength was significantly greater in extension than flexion. The reduction in flexion strength did not reach statistical significance. The extensor weakness was primarily due to decreased tonic activation of the extensor muscles and not to muscle coactivation. Muscle relaxation time was much more prolonged than was force generation time or active force return time. The increase in relaxation time and the decrease in extensor strength both correlated with changes in clinical status. Finally, changes in extensor torque correlated with the time to actively return force, suggesting that reduced strength is related to a reduced ability to generate rapid contractions in some patients with Parkinson's disease. These results suggest that there is an asymmetric distribution of muscle weakness in Parkinson's disease and that selected measures of muscle strength and muscle relaxation correlate with changes in clinical status.

Psychotic and depressive symptoms in Parkinson's disease. A study of the growth hormone response to apomorphine

BACKGROUND

The growth hormone (GH) response to apomorphine, thought to reflect central dopaminergic receptor sensitivity, has been reported as enhanced in acute schizophrenia. We investigated this response in relation to the psychotic episodes associated with Parkinson's disease (PD).

METHOD

The GH response to apomorphine was measured in three groups of patients with Parkinson's disease: those currently psychotic (n = 9), those with a past history of psychosis (n = 7) and those who had never been psychotic (n = 8).

RESULTS

Apomorphine-induced GH response was not related to psychosis but was unexpectedly associated with measures of depression.

CONCLUSIONS

Visual hallucinations were a prominent feature in the psychotic patients and the atypical nature of these psychoses might explain why we found no evidence of dopaminergic sensitivity. Serotonergic dysfunction would be in keeping with this. Dopaminergic mechanisms may contribute to the minor depressive symptomatology seen in PD.

A clinical and pharmacokinetic case study of an interaction of levodopa and antituberculous therapy in Parkinson's disease

We studied the relationship between levodopa response and antituberculous treatment in a patient with idiopathic Parkinson's disease whose parkinsonism deteriorated when treatment with rifampicin and isoniazid (Rifinah) for pulmonary tuberculosis was started. A levodopa challenge test with regular recording of motor function was performed during, and again after stopping, antituberculous treatment. Plasma levodopa and levodopa metabolite pharmacokinetic profiles were determined using standard techniques. "On" period duration was 75% longer after antituberculous treatment had been stopped. These clinical findings correlated with a 37% increase in area under the concentration versus time curve (AUC), a 103% increase in apparent elimination half-life (t1/2), a 41% increase in time to maximum concentration (Tmax), and a 33% decrease in maximum concentration (Cmax) of levodopa. A concurrent increase in plasma 3-O-methyldopa (3-OMD) and a decrease in plasma 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), the three major metabolites of levodopa, suggests an inhibition of the enzyme dopa decarboxylase, probably by isoniazid.

Striatal opioid receptor binding in Parkinson's disease, striatonigral degeneration and Steele-Richardson-Olszewski syndrome, A [11C]diprenorphine PET study

The clinical differentiation of Parkinson's disease from the striatonigral degeneration (SND) type of multiple system atrophy (MSA) and Steele-Richardson-Olszewski syndrome (SRO) may be difficult. This is reflected by a 20-25% misdiagnosis rate in clinicopathological series of cases labelled as 'Parkinson's disease' in life. The caudate and putamen contain a high density of opioidergic neurons and receptors which have a close anatomical and physiological relationship with the dopaminergic system. We used [11C]diprenorphine with PET to investigate striatal opioid receptor binding in groups of patients with clinically defined Parkinson's disease (n = 8), SND (n = 7) and SRO (n = 6), compared with normal controls (n = 8). There was no significant difference between mean ligand binding in the putamen and caudate of Parkinson's disease cases when compared with normals. Mean putamen, but not caudate, opioid receptor binding was significantly reduced in the SND group, when compared with normals. By contrast, in the SRO group, both mean caudate and putamen opioid receptor binding was significantly reduced when compared with both normal and Parkinson's disease groups. When considering the individual patients, none of the eight Parkinson's disease cases (0%), none of the seven SND cases (0%), but four of the six SRO cases (67%) had caudate opioid receptor binding that was > 2.5 SDs below the normal mean. Corresponding figures for putamen opioid receptor binding were: none of the Parkinson's disease cases (0%); three of the SND cases (43%); and all of the SRO cases (100%). We conclude that there are differences in the pattern of opioid receptor binding in the striatum of Parkinson's disease, SND and SRO patients, as determined by [11C]diprenorphine PET. The different binding patterns may help to differentiate these akinetic-rigid syndromes in life.

[Multiple system atrophy with Lewy bodies]

The term multiple system atrophy has been used to define a unique sporadic neurodegenerative disease, usually occurring in midlife, pathologically characterized by degeneration of the nigro-striato-pallidal and olivo-ponto-cerebellar systems and autonomic neurons of the spinal cord, and by the presence of characteristic oligodendroglial inclusions. In many cases, this disease can be readily distinguished, both clinically and pathologically, from idiopathic Parkinson's disease. However, often clinical differentiation is difficult, and in a few autopsied cases the presence of Lewy bodies, the characteristic inclusion of idiopathic Parkinson's disease, can lead to diagnostic confusion. Such a pathological association, named the "transitional variant" by some authors, is of unknown clinical and pathological significance. We here report three new cases of such an association from the United Kingdom Parkinson's Disease Society Brain Bank. Clinical and pathological data derived from these new observations, as well as from literature cases, tend to suggest that this pathological association is of no particular clinical significance. The comparison of the prevalence of Lewy bodies in normal elderly individuals and in multiple system atrophy suggests a chance association of the two pathologies. However, the small number of cases so far studied as well as the heterogeneity of series analyzed does not exclude the presence of common susceptibility factors for both diseases.

CYP2D6-debrisoquine hydroxylase gene polymorphism in multiple system atrophy

Molecular genetic studies of the cytochrome P450 system enzyme CYP2D6, which hydroxylates debrisoquine, have indicated an excess of mutant alleles in large series of patients with Parkinson's disease (PD) when compared with controls. We have investigated CYP2D6 polymorphism in 91 patients with multiple system atrophy (MSA) in order to determine if this finding is specific to PD or if there is similar evidence of genetic susceptibility to neurotoxicity in MSA. The distribution of CYP2D6 alleles was not significantly different between MSA patients and controls, and there were fewer poor metabolisers in the MSA group than in the control group.

Positron emission tomography studies on the dopaminergic system and striatal opioid binding in the olivopontocerebellar atrophy variant of multiple system atrophy

Ten patients with sporadic olivopontocerebellar atrophy and autonomic failure were studied with positron emission tomography. Subjects underwent both an [11C]diprenorphine and an [18F]fluorodopa scan. The mean caudate-occipital uptake ratio for [11C]diprenorphine was significantly reduced to 88% and the putamen-occipital uptake ratio to 85% of the control values. Individually, 4 of the 10 patients had significantly reduced opioid binding in the putamen. Mean putamen [18F]fluorodopa uptake was significantly diminished (to 71% of the control mean); individually 7 patients had significantly reduced uptake. There was a significant positive correlation between putamen-occipital uptake ratios for [11C]diprenorphine and putamen uptake of [18F]fluorodopa. Our results suggest that subclinical nigrostriatal dysfunction is present in the majority of patients with sporadic olivopontocerebellar atrophy, in accordance with it being part of the spectrum of multiple system atrophy.

Nerve conduction studies, skeletal muscle EMG, and sphincter EMG in multiple system atrophy

Although autonomic failure, parkinsonism, and cerebellar and pyramidal signs are well documented in multiple system atrophy, much less is known about the frequency and severity of involvement of the peripheral nervous system. The frequency and nature of peripheral nerve involvement has therefore been determined in 74 patients with multiple system atrophy using nerve conduction studies and skeletal muscle EMG. These findings were compared with those on sphincter EMG. Ninety per cent of the patients had an abnormal sphincter EMG, indicating denervation and reinnervation consistent with anterior horn cell loss in Onuf's nucleus, but only 40% had either abnormal nerve conduction studies (mixed sensorimotor axonal neuropathy in 17.5%) or abnormal skeletal muscle EMG (suggesting partial denervation in 22.5%). These data indicate a remarkable selective vulnerability of the anterior horn cells of Onuf's nucleus innervating external sphincter muscles relative to those supplying skeletal muscle in patients with multiple system atrophy. If this selective pattern of involvement can be explained it may be a clue to pathogenetic mechanisms in multiple system atrophy.

Comparison of executive and visuospatial memory function in Huntington's disease and dementia of Alzheimer type matched for degree of dementia

Groups of patients with Hungington's disease and probable dementia of Alzheimer type (DAT) matched for level of dementia on the basis of mini mental state examination scores were compared in several tests of visual memory and tests sensitive to frontal lobe dysfunction. Whereas recall of patients with DAT tended to be worse on the Kendrick object learning test, the two groups were equivalent on tests of sensorimotor ability and delayed matching to sample performance. By contrast, the patients with Huntington's disease were significantly worse on tests of pattern and spatial recognition, simultaneous matching to sample, visuospatial paired associates, and on three tests sensitive to frontal lobe dysfunction--namely, the Tower of London test of planning, spatial working memory, and a visual discrimination learning and reversal paradigm. The impairments in these tests, however, did not always qualitatively resemble those seen in patients with frontal lobe damage and may be more characteristic of primary neostriatal deficit. In the visual discrimination paradigm the patients with Hungtington's disease were significantly worse than the patients with DAT at the simple reversal stage, where they displayed significant preservation to the previously rewarded alternative. The results are consistent with the hypothesis that patients with Huntington's disease exhibit deficits in tests sensitive to frontostriatal dysfunction and that this form of intellectual deterioration is qualitatively distinct from that seen in Alzheimer's disease.