Micturitional disturbance in progressive supranuclear palsy

Autonomic dysfunction in progressive supranuclear palsy

BACKGROUND

The degree of involvement of the autonomic nervous system in progressive supranuclear palsy (PSP) has been investigated in several studies, often providing conflicting results. There is a need for a better characterization of autonomic dysfunction in PSP, to enhance our understanding of this highly disabling neurodegenerative disease including patients' needs and possibly be of value for clinicians in the differential diagnosis among Parkinsonian syndromes.

METHODS

We applied a systematic methodology to review existing literature on Pubmed regarding autonomic nervous system involvement in PSP.

RESULTS

PSP reported quite frequently symptoms suggestive of autonomic dysfunction in all domains. Cardiovascular autonomic testing showed in some cases a certain degree of impairment (never severe). There was some evidence suggesting bladder dysfunction particularly in the storage phase. Dysphagia and constipation were the most common gastrointestinal symptoms. Instrumental tests seemed to confirm sudomotor and pupillomotor disturbances.

CONCLUSIONS

PSP patients frequently reported visceral symptoms, however objective testing showed that not always these reflected actual autonomic impairment. Further studies are needed to better delineate autonomic profile and its prognostic role in PSP.

Lower urinary tract dysfunction in Parkinsonian syndromes

PURPOSE OF REVIEW

The aim of this review is to outline the clinical presentation, pathophysiology and evaluation of lower urinary tract (LUT) dysfunction in Parkinson's disease and other parkinsonian syndromes including multiple system atrophy, dementia with Lewy bodies, progressive supranuclear palsy and corticobasal degeneration.

RECENT FINDINGS

LUT dysfunction commonly occurs in neurological disorders, including patients with parkinsonian syndromes. The pattern of LUT dysfunction and its severity are variable, depending upon the site of lesion within the neural pathways. Parkinsonian syndromes are broadly divided into Parkinson's disease (PD) and a typical parkinsonian syndromes such as multiple system atrophy (MSA), dementia with Lewy bodies (DLB), progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD). Different parkinsonian syndromes have distinct clinical features (e.g. dysautonomia, early dementia, supranuclear gaze palsy, higher cortical signs), and the pattern of LUT dysfunction and its severity can differ.

CONCLUSIONS

LUT dysfunction is a common feature in patients with parkinsonian syndromes. Recognising the pattern of LUT dysfunction during the assessment of these patients can help management and possibly facilitate an earlier diagnosis.

Cutaneous sensory and autonomic denervation in progressive supranuclear palsy

AIM

Progressive Supranuclear Palsy (PSP) is a progressive neurodegenerative tauopathy characterised by motor, behavioural and cognitive dysfunction. While in the last decade, sensory and autonomic disturbances as well as peripheral nerve involvement are well-recognised in Parkinson's Disease (PD), little is known in this regard for PSP. Herein, we aim to assess peripheral sensory and autonomic nerve involvement in PSP and to characterise possible differences in morpho-functional pattern compared to PD patients.

METHODS

We studied 27 PSP and 33 PD patients without electrophysiological signs of neuropathy, and 33 healthy controls (HC). In addition to motor impairment, evaluated by means of UPDRS-III and the PSP rating scale, all patients underwent clinical, functional and morphological assessment of sensory-autonomic nerves through dedicated questionnaires, sympathetic skin response, dynamic sweat test and skin biopsies. The analysis of cutaneous sensory and autonomic innervation was performed using indirect immunofluorescence and confocal microscopy.

RESULTS

PSP patients displayed a length-dependent loss of sensory and autonomic nerve fibres associated with functional impairment compared to HC and, overall, a more severe picture than in PD patients. The disease severity correlated with the loss of intraepidermal nerve fibre density in the leg of PSP patients (p < 0.05).

CONCLUSION

We demonstrated a length-dependent small fibre pathology in PSP, more severe compared to PD, and paralleling disease severity. Our findings suggest the morphological and functional study of cutaneous nerves as possible biomarkers to monitor disease progression and response to new treatments.

The Non-Motor Symptom Profile of Progressive Supranuclear Palsy

OBJECTIVE

Non-motor symptoms (NMSs) significantly contribute to increased morbidity and poor quality of life in patients with parkinsonian disorders. This study aims to explore the profile of NMSs in patients with progressive supranuclear palsy (PSP) using the validated Non-Motor Symptom Scale (NMSS).

METHODS

Seventy-six patients with PSP were evaluated in this study. Motor symptoms and NMSs were evaluated using the PSP Rating Scale (PSPRS), Unified Parkinson's Disease Rating Scale-III, Montreal Cognitive Assessment, Hamilton Depression (HAM-D) and Anxiety Rating Scales, Parkinson's Disease Sleep Scale (PDSS) and NMSS. NMS severity and prevalence were also compared between patients with PSP-Richardson syndrome (PSP-RS) and those with PSP-parkinsonism.

RESULTS

All subjects in this cohort reported at least 2 NMSs. The most prevalent NMSs in patients with PSP were in the domains of sleep/fatigue, mood/cognition, and sexual function. The least prevalent NMSs were in the domains of cardiovascular including falls, and perceptual problems/hallucinations. Significant correlations were observed between the NMSS scores and HAM-D, PDSS, PSPRS scores and PSPRS sub-scores. The severity of NMSs was unrelated to the duration of illness. Patients with PSP-RS reported a higher severity of drooling, altered smell/taste, depression and altered interest in sex and a higher prevalence of sexual dysfunction.

CONCLUSION

NMSs are commonly observed in patients with PSP, and the domains of sleep, mood and sexual function are most commonly affected. These symptoms contribute significantly to disease morbidity, and clinicians should pay adequate attention to identifying and addressing these symptoms.

Neurogenic bladder in progressive supranuclear palsy: A comparison with Parkinson's disease and multiple system atrophy

AIMS

Progressive supranuclear palsy (PSP) can present urinary symptoms, similar to other parkinsonian disorders. We investigated the urodynamic parameters of PSP and compared them with those of idiopathic Parkinson's disease (IPD) and multiple system atrophy (MSA) METHODS: We retrospectively analyzed the urodynamic data in patients diagnosed with parkinsonian disorders (PSP, IPD, and MSA) presenting urinary symptoms. Clinical data, including onset age, duration, and severity, as well as treatment status of parkinsonian disorders and urinary symptoms were collected.

RESULTS

A total of 131 patients (10 with PSP, 79 with IPD, and 42 with MSA) were included. The mean age and disease onset age of PSP patients were similar to those of IPD patients, but older than those of MSA patients. The disease duration until the onset of urinary symptoms in PSP patients was similar to that in MSA patients, but shorter than that in IPD patients. According to the urodynamic study, storage phase dysfunctions in PSP patients were similar to those in IPD or MSA patients. However, according to a pressure-flow study, PSP patients showed higher rates of voiding failure, as well as lower maximum flow rate, higher post-void residual volume, and higher proportions of impaired detrusor contraction than IPD patients, but rather similar to MSA patients.

CONCLUSIONS

Urinary dysfunctions in PSP patients were as extensive as those with MSA, and were more severe than those with IPD, especially in the voiding phase. This may reflect the extensive degenerative process of neural structure in PSP patients.

Non motor symptoms in progressive supranuclear palsy: prevalence and severity

NMSs have been extensively studied in PD patients but not in other forms of parkinsonism such as Progressive Supranuclear Palsy (PSP). The primary objective of this study was to analyze the frequency, severity and the type of non-motor symptoms (NMS) in PSP patients using the non-motor symptoms scale (NMSS). The secondary objective was to differentiate NMS between PSP and Parkinson’s disease (PD). We enrolled in this cross-sectional study 50 consecutive PSP and 100 matched Parkinson’s disease (PD) patients, in the proportion PSP/PD = 1/2, matched in age, sex, and disease duration. Motor and Non Motor symptoms (different scales for each disease) were evaluated at baseline using PSP scale, SCOPA Motor, Montreal Cognitive Assessment (MOCA), HADS, Hamilton, and Non Motor Symptom scale (NMSS). Comparative analysis was done using chi-squared test, Mann-Whitney test and Fisher’s exact test. Fifty PSP (56% female) and 100 PD (59% female) patients completed the study protocol and were included for statistical analysis. The NMSS total domains score in the PSP group was 77.58 ± 42.95 (range 14–163) with NMS burden grade: 4, very severe, and the in the PD group was 41.97 ± 35.45 (range: 0–215) with NMS burden grade: 3, severe. The comparative analysis showed that NMS total score (p < 0.0001), Sleep/Fatigue (p = 0.0007), Mood/Apathy (p = 0.0001), Gastrointestinal (p < 0.0001), and Urinary dysfunction (p = 0.0001) domains were significantly more severe in PSP patients than in PD. This observational study reports that NMSs are very frequent in PSP patients hence the higher burden of NMS in PSP specifically related to mood/apathy, attention/memory, gastrointestinal, urinary disturbances compared to PD.

Non-motor symptoms are more frequent and severe in patients with Progressive Supranuclear Palsy (PSP) than in those with Parkinson’s disease (PD). An international team led by Fabrizio Stocchi at the Institute for Research and Medical Care IRCCS in Rome used the Non-motor Symptoms Scale (NMSS) to compare the symptoms experienced by 50 PSP patients and 100 PD patients. They found that patients with PSP suffered worse and more frequent gastrointestinal and urinary disturbances, as well as more severe dysfunctions in attention and memory compared with PD patients. Moreover, the reported lack of motivation and sleep disturbances were more burdensome in PSP patients. These findings will not only contribute to diagnose PSP earlier and more accurately, but also help to increase awareness of the impact of non-motor symptoms on patients’ quality of life.

A guideline for the management of bladder dysfunction in Parkinson's disease and other gait disorders

Parkinson's disease (PD) is a common neurodegenerative disorder, and lower urinary tract (LUT) dysfunction is one of the most common autonomic disorders with an estimated incidence rate of 27-80%. Studies have shown that bladder dysfunction significantly influences quality-of-life (QOL) measures, early institutionalisation, and health economics. We review the pathophysiology of bladder dysfunction in PD, lower urinary tract symptoms (LUTS), objective assessment, and treatment options. In patients with PD, disruption of the dopamine D1-GABAergic direct pathway may lead to LUTS. Overactive bladder (OAB) is the most common LUT symptom in PD patients, and an objective assessment using urodynamics commonly shows detrusor overactivity (DO) in these patients. The post-void residual (PVR) volume is minimal in PD, which differs significantly from multiple system atrophy (MSA) patients who have a more progressive disease that leads to urinary retention. However, subclinical detrusor weakness during voiding may also occur in PD. Regarding bladder management, there are no large, double-blind, prospective studies in this area. It is well recognised that dopaminergic drugs can improve or worsen LUTS in PD patients. Therefore, an add-on therapy with anticholinergics is required. Beta-3 adrenergic agonists are a potential treatment option because there are little to no central cognitive events. Newer interventions, such as deep brain stimulation (DBS), are expected to improve bladder dysfunction in PD. Botulinum toxin injections can be used to treat intractable urinary incontinence in PD. Transurethral resection of the prostate gland (TURP) for comorbid BPH in PD is now recognised to be not contraindicated if MSA is excluded. Collaboration of urologists with neurologists is highly recommended to maximise a patients' bladder-associated QOL. Neurourol. Urodynam. 35:551-563, 2016. © 2015 Wiley Periodicals, Inc.

Vascular incontinence: incontinence in the elderly due to ischemic white matter changes

This review article introduces the new concept of vascular incontinence, a disorder of bladder control resulting from cerebral white matter disease (WMD). The concept is based on the original observation in 1999 of a correlation between the severity of leukoareosis or WMD, urinary symptoms, gait disorder and cognitive impairment. Over the last 20 years, the realization that WMD is not a benign incidental finding in the elderly has become generally accepted and several studies have pointed to an association between geriatric syndromes and this type of pathology. The main brunt of WMD is in the frontal regions, a region recognized to be crucial for bladder control. Other disorders should be excluded, both neurological and urological, such as normal-pressure hydrocephalus, progressive supranuclear palsy, etc., and prostatic hyperplasia, physical stress incontinence, nocturnal polyuria, etc. Treatment involves management of small vessel disease risk factors and anticholinergic drugs that do not easily penetrate the blood brain barrier to improve bladder control.

Progressive supranuclear palsy presenting with urinary retention and sleep apnea

We report a case of a 62-year-old Japanese-Australian woman with progressive supranuclear palsy (PSP) who presented with prominent urinary retention, neurogenic changes in sphincter electromyography, and obstructive sleep apnea syndrome. Urodynamic study revealed a combination of detrusor overactivity during filling and underactivity during voiding. All these non-motor symptoms in PSP mimicked those of multiple system atrophy.

Anal sphincter EMG in the diagnosis of parkinsonian syndromes

BACKGROUND

The role of electromyography (EMG) recorded from the external anal sphincter (EAS) in the diagnosis of atypical parkinsonian syndromes is a matter for continuous debate. Most studies addressing this issue are retrospective.

METHODS

In this study, we prospectively investigated six patients with Parkinson's Disease (IPD), 14 patients with multiple system atrophy (MSA) and eight with progressive supranuclear palsy (PSP) using EMG of the EAS, motor-evoked potential (MEP) to the EAS and EMG of m. gastrocnemius and nerve conduction velocity measured at the sural nerve. Patients were followed up for 2 years to secure correct diagnosis.

RESULTS

The mean duration of motor unit potentials (MUPs) recorded from the EAS was significantly longer in patients with MSA and PSP compared with MUPs recorded from patients with PD (P < 0.005 for both). There were no signs of diffuse loss of motor neurons or peripheral neuropathy. MEP revealed signs of supranuclear affection in patients with MSA, whereas in patients with PSP the mechanism is a focal loss of motor neurons in Onuf's nucleus.

CONCLUSION

Abnormal EMG of the EAS is strongly suggestive of atypical parkinsonism and the pathophysiology may be different in patients with MSA and PSP.

Bladder dysfunction in Parkinsonism: Mechanisms, prevalence, symptoms, and management

The advent of functional imaging methods has increased our understanding of the neural control of the bladder. This review examines current concepts of the role of brain function in urinary control with particular emphasis on the putative role of dopamine receptors. Dopaminergic mechanisms play a profound role in normal bladder control and the dysfunction of these may result in symptoms of overactive bladder in Parkinsonism. The importance of this nonmotor disorder has been overlooked. We address the problem of bladder dysfunction as it presents to patients and their neurologist. The prevalence of bladder symptoms in Parkinson's disease is high; the most common complaint is nocturia followed by frequency and urgency. In multiple-system atrophy, the combination of urge and urge incontinence and poor emptying may result in a complex combination of complaints. The management of bladder dysfunction in Parkinsonism addresses treatment of overactive detrusor as well as incontinence.

Neurological diseases that cause detrusor hyperactivity with impaired contractile function

AIMS

Detrusor hyperactivity with impaired contractile function (DHIC) was originally described in elderly women. It has not previously been well known whether neurological diseases cause DHIC. We investigated which neurological diseases commonly cause DHIC in our laboratory.

MATERIALS AND METHODS

We searched for DHIC in our laboratory's computerized database of 1,514 case records, which included a lower urinary tract (LUT) symptom questionnaire and urodynamic study results. DHIC was defined as the presence of both (1) detrusor overactivity during the storage phase, and (2) underactive detrusor contraction during the evacuation phase.

RESULTS

Two hundred and seventeen patients met the criteria for DHIC: 122 men and 95 women; mean age, 63 years. The neurological diseases that caused DHIC included Parkinsonian syndrome (18%), multiple system atrophy (18%), progressive supranuclear palsy/corticobasal degeneration (14%), multiple cerebral infarction (MCI) (12%), multiple sclerosis/acute disseminated encephalomyelitis (18%), spinal cord lesions (15%), and cervical spondylotic myelopathy (CS) (10%).

CONCLUSIONS

The present study revealed that a wide spectrum of neurological disorders could cause DHIC.

How to diagnose MSA early: the role of sphincter EMG

Multiple system atrophy (MSA) is a degenerative disease manifesting a combination of parkinsonism, cerebellar, pyramidal, and autonomic (including urinary, sexual and anorectal) dysfunction. It is pathomorphologically defined, but lacks a definitive clinical diagnostic test. In patients with probable MSA, abnormal sphincter EMG, as compared to control subjects, has been found in the majority of patients in all the different forms of the disease in most studies, including patients who, as yet, have no urological or anorectal problems. Patients with Parkinson's disease (PD) as a rule do not show marked sphincter EMG abnormalities in the first five years of the disease. Thus, abnormal spontaneous activity or marked motor unit potential changes in sphincter muscles are helpful in distinguishing MSA from PD in the first five years after the onset of symptoms and signs, and from pure autonomic failure, as well as from cerebellar ataxias, if other causes for sphincter denervation have been ruled out. EMG does not distinguish MSA from progressive supranuclear palsy. How early in the course of MSA these abnormalities become significant enough to support diagnosis remains to be established by prospective studies.

Reference values of motor unit potentials (MUPs) of the external anal sphincter muscle

OBJECTIVE

To provide reference values for the isolated motor unit potentials (MUPs) in the external anal sphincter (EAS) muscle, as mean duration, mean amplitude, mean area, number of turns and number of phases, related to the age of the patient. These data are not available in worldwide literature in spite of the fact that the EAS muscle is being increasingly mentioned in relation to differential diagnosis.

METHODS

Study of 235 subjects aged 0-80 years using an automated analysis program.

RESULTS

The study performed shows a clear gradual progression of the mean duration with patient age. The variability of all other parameters tested is also analyzed.

CONCLUSIONS

Our study shows that the classical values of MUPs isolated in the EAS muscle are directly related to age, and that this method is fully reliable to study its pathological conditions.

Progressive supranuclear palsy: neuronal and glial cytoskeletal pathology in the higher order processing autonomic nuclei of the lower brainstem

The medial and lateral parabrachial nuclei (MPB, LPB), the gigantocellular reticular nucleus (GI), the raphes magnus (RMG) and raphes obscurus nuclei (ROB), as well as the intermediate reticular zone (IRZ) represent pivotal subordinate brainstem centres, all of which control autonomic functions. In this study, we investigated the occurrence and severity of the neuronal and glial cytoskeletal pathology in these six brainstem nuclei from 17 individuals with clinically diagnosed and neuropathologically confirmed progressive supranuclear palsy (PSP). The association between the severity of the pathology and the duration of the disease was investigated by means of correlation analysis. The brainstem nuclei in all of the PSP cases were affected by the neuronal cytoskeletal pathology, with the IRZ and GI regularly showing severe involvement, the MPB, RMG, and ROB marked involvement, and the LPB mild involvement. In the six nuclear greys studied, glial cells undergo alterations of their cytoskeleton on an irregular basis, whereby diseased oligodendrocytes predominantly presented as coiled bodies and affected astrocytes as thorn-shaped astrocytes. In all six nuclei, the severity of the neuronal or glial cytoskeletal pathology showed no correlation with the duration of PSP. In view of their functional role, the neuronal pathology in the nuclei studied offers a possible explanation for the autonomic dysfunctions that eventually develop in the course of PSP.

Sphincter EMG and differential diagnosis of multiple system atrophy

Multiple system atrophy (MSA) is a degenerative disease manifesting a combination of parkinsonism, cerebellar, pyramidal, and autonomic (including urinary, sexual, and anorectal) dysfunction. It is pathomorphologically defined, but lacks a definitive clinical diagnostic test. Sphincter electromyography (EMG), reflecting Onuf's nucleus degeneration, has been proposed as a helpful test; its value has been reevaluated by a critical review of the literature. In patients with probable MSA, abnormal sphincter EMG, as compared to control subjects, has been found in the majority of patients in all the different forms of the disease in most studies, including patients who, as yet, have no urological or anorectal problems. The prevalence of abnormalities in the early stages of MSA is as yet unclear. Patients with Parkinson's disease (PD) as a rule do not show severe sphincter EMG abnormalities in the early stage of the disease. Anal sphincter EMG abnormalities (abnormal spontaneous activity or motor unit potential changes three standard deviations above valid control data) distinguish MSA from PD in the first 5 years after the onset of symptoms and signs, and from pure autonomic failure, as well as from cerebellar ataxias, if other causes for sphincter denervation have been ruled out. With such criteria, the sensitivity of the method is, however, low. EMG does not distinguish MSA from progressive supranuclear palsy. Future studies should use standardized anal sphincter EMG to better compare results from different centers and precisely define the sensitivity and specificity of the method.

Standardization of anal sphincter electromyography: normative data

OBJECTIVES

Electromyography (EMG) of the external anal sphincter (EAS) is important in the evaluation of conus/cauda lesions, the differential diagnosis of parkinsonism and anal incontinence. The aim of our study was to establish normative data in a sufficiently large group of healthy subjects, using a rigorously standardized examination technique.

METHODS

Sixty-four subjects (aged 19-83 years) without pelvic or neurological disorders were included. Motor unit potentials (MUPs)/interference pattern (IP) samples were obtained from the EAS using multi-MUP and turn/amplitude analyses, respectively. The effect of age, gender, parity, and constipation on MUP/IP parameters was studied. For MUP parameters the lower/upper limits for mean values, and 'outlier' limits, and for IP parameters normal 'clouds' were calculated.

RESULTS

From 112 muscles 15-30 MUPs were sampled. As no effect of evaluated factors on mean values could be demonstrated, common reference values were calculated. Lower/higher limits for mean values were: amplitude 148/661 microV, duration 3.2/7.8 ms, area 87/625 microVms, and number of phases 2. 3/3.7. 'Outlier' limits for individual MUPs were: amplitude 84/1315 microV, duration 1.6/13.8 ms, area 46/1222 microVms, number of phases 2/6. From 95 muscles 2706 IP samples were obtained.

CONCLUSIONS

The presented normative data should allow valid quantitative EMG of the EAS muscle in patients.

Time course of symptomatic orthostatic hypotension and urinary incontinence in patients with postmortem confirmed parkinsonian syndromes: a clinicopathological study

OBJECTIVE

Although both orthostatic hypotension and urinary incontinence have been reported in a number of parkinsonian syndromes, such as Parkinson's disease (PD), multiple system atrophy (MSA), dementia with Lewy bodies (DLB), corticobasal degeneration (CBD), and progressive supranuclear palsy (PSP), differences in the evolution of these features have not been studied systematically in pathologically confirmed cases.

METHODS

77 cases with pathologically confirmed parkinsonian syndromes (PD, n=11; MSA, n=15; DLB, n=14; CBD, n=13; PSP, n=24), collected up to 1994, formed the basis for a multicentre clinicopathological study organised by the NINDS to improve the differential diagnosis of parkinsonian disorders. The present study determined the time course-that is, latency to onset and duration from onset to death, of symptomatic orthostatic hypotension, and urinary incontinence in the NINDS series. Furthermore, the diagnostic validity of a predefined latency to onset within 1 year of disease onset of symptomatic orthostatic hypotension or urinary incontinence was analysed.

RESULTS

Significant group differences for latency, but not duration, of symptomatic orthostatic hypotension and urinary incontinence were found. Latencies to onset of either feature were short in patients with MSA, intermediate in patients with DLB, CBD, and PSP, and long in those with PD. Symptomatic orthostatic hypotension occurring within the first year after disease onset predicted MSA in 75% of cases; early urinary incontinence was less predictive for MSA (56%).

CONCLUSION

Latency to onset, but not duration, of symptomatic orthostatic hypotension or urinary incontinence differentiates PD from other parkinsonian syndromes, particularly MSA.

Neurological disorders of micturition and their treatment

An overview of the current concepts of the neurological control of the bladder is given, based on laboratory experiments and PET scanning studies in human subjects. This is followed by a description of the various causes of the neurogenic bladder, discussed in a hierarchical order starting with cortical lesions and descending through the basal ganglia and brainstem, spinal cord, conus and cauda equina to disorders of peripheral innervation. Then follows a description of the condition of isolated urinary retention in young women. The article concludes with a review of the methods available for treating neurogenic bladder disorders. These are largely medical but brief mention of appropriate surgical procedures is made.

Clinical and genetic aspects of progressive supranuclear palsy

Progressive supranuclear palsy (PSP) is, after Parkinson's disease, the most common form of degenerative parkinsonism. Several clinical features are used in the recognition of this disorder as well as in the differentiation from related disorders. Clinical criteria that could increase diagnostic accuracy in research studies are also emphasized. Due to a better understanding of the genetic aspects of PSP, recent studies have suggested that it is a recessive disorder in linkage disequilibrium with the tau (tau) gene, rather than a sporadic disorder. In addition, the recent identification of mutations in the tau gene associated with a similar neurodegenerative condition (frontotemporal dementia and parkinsonism linked to chromosome 17) has further strengthened the argument that tau dysfunction is somehow involved in the pathogenesis of PSP. Nongenetic factors that could trigger or perpetuate the cascade of events leading to neuronal degeneration in PSP are also reviewed.

Value of sphincter electromyography in the diagnosis of multiple system atrophy

It is clinically important, to distinguish between idiopathic Parkinson's disease (IPD) and multiple system atrophy (MSA) not only because of the implications for prognosis but also because urinary incontinence is often an early troublesome feature of MSA and by making the correct neurological diagnosis inappropriate urological surgery may be avoided. Onuf's nucleus in the sacral cord is the location of the anterior horn cells innervating the sphincters, and it is among central nervous system sites affected by neuronal cell loss in MSA but not in IPD. A systematic analysis of motor units recorded from the sphincter looking for changes of chronic reinnervation has therefore been used to distinguish between these conditions. Sphincter electromyography (EMG) was carried out in 126 patients with suspected MSA with review of their case notes up to 2 years later. Of those in whom a diagnosis of MSA was made, 82% had had an abnormal sphincter EMG.

Micturitional disturbance in myotonic dystrophy

Micturitional disturbance has attracted little attention in myotonic dystrophy, but detailed micturitional histories revealed that two out of six patients (33%) had micturitional symptoms. One had difficulty urinating and the other had urinary frequency, urgency and stress incontinence. Urodynamic studies were performed in all patients and the results were as follows: Two had low maximum urethral closure pressure, two had large and three had small bladder capacities, one had detrusor hyperreflexia and one had atonic cystometrogram. Urethral sphincter electromyography revealed a decreased bulbocavernosus reflex in one, and an absent anal reflex in two. Motor unit analysis of external sphincter was performed with one patient and showed polyphasic potentials. Dystrophic changes of the lower urinary tract muscles, as well as supranuclear type of pelvic nerve dysfunction, could cause micturitional disturbance in patients with myotonic dystrophy.