PubMed Health⌕ Search

Biomedical subjects

O Suchowersky

Publications and source records attributed to O Suchowersky.

At least 37 records · Page 2Linked to original sources

COMT inhibitors in Parkinson's disease.

The COMT inhibitors, tolcapone and entacapone, are a new class of Parkinson's medications. By inhibiting the enzyme catechol-o-methyl-transferase (COMT), they prevent peripheral degradation of levodopa, allowing a higher concentration to cross the blood-brain barrier. Pharmacokinetic studies have shown that both tolcapone and entacapone significantly prolong the elimination half life, and increase the area under the curve of levodopa without increasing C max. Clinical studies with COMT inhibitors have shown benefit in both stable and fluctuating PD patients with improvement in motor function with lower levodopa doses. Fluctuating patients also had increased "on" time and reduced "wearing off". Side effects were most commonly related to increased dopaminergic stimulation. Specific side effects included diarrhea and elevated liver enzymes. The recent reports of three cases of fulminant hepatitis with the use of tolcapone has led many countries to remove this compound from their market. Concerns about a possible class effect should impose close monitoring of liver function tests with the use of any of the nitrocatechols.

Antiparkinson Agents↗

Parkinson's disease management: towards a new paradigm.

Over the past decade, management of Parkinson's disease has changed significantly due to the expansion of medical and surgical treatment modalities. Neurologists now have the ability (and the challenge) of choosing from multiple medications to devise an individual management strategy for each patient depending on his/her clinical symptoms and needs. Several different surgical therapies are also available. The topics covered in this supplement have highlighted the new options that are now available, as well as the treatments that have been in clinical usage. This review attempts to synthesize the information that is currently available in an attempt to help clinical neurologists make the appropriate choice for their patients.

Catechol O-Methyltransferase Inhibitors↗

Management of Parkinson's disease a review of current and new therapies.

The management of Parkinson's disease has undergone recent changes with the advent of new therapies, both pharmacotherapy and surgery. Available interventions are discussed. Levodopa remains the mainstay of therapy. New drugs include the dopamine agonists and COMT inhibitors. New dopamine agonists which may have a levodopa "sparing effect;" it has been suggested that some of the drugs should be considered as first line treatments for newly diagnosed Parkinson's disease patients. We review roles of these drugs. The concept of neuroprotection in neurodegenerative disorders such as Parkinson's disease became popular in the mid 1980s and it is hoped that eventually therapy will be directed at slowing progression of the disease. A great deal more work needs to be done before a suitable agent is identified as being neuroprotective. Potential neuroprotective agents are reviewed. Surgical therapies for Parkinson's disease consisting of various forms of lesion surgery as well as stimulation procedures are reviewed. Complications of drug therapy include motor problems such as motor response fluctuations, as well as psychiatric complications including levodopa-induced psychosis. Atypical neuroleptic agents and ECT for psychiatric syndromes associated with Parkinson's disease are discussed. Algorithms for the management of early disease as well as the management of psychosis in Parkinson's disease are included. Treatment options for advanced disease are tabulated.

Antiparkinson Agents↗

Congenital autosomal dominant distal spinal muscular atrophy.

We present a father and son with congenital foot deformity. The father at age 41 years used crutches and the son at 7 years walked unaided. Both had atrophy and weakness of lower leg muscles and mild proximal and hand intrinsic weakness. Knee and ankle myotactic reflexes were absent and sensation was intact. Creatine kinase level was normal, nerve conduction studies wer normal and electromyography showed chronic neurogenic change. In both, nerve biopsies were normal and muscle biopsies showed type 1 predominance. The boy's serum hexosaminidase, spinal MRI and SMN gene were normal. This may be the first well documented example of congenital autosomal dominant distal spinal muscular atrophy affecting legs and arms.

Adult↗

Cognitive manifestations of Huntington disease in relation to genetic structure and clinical onset.

OBJECTIVE: To examine the cognitive manifestations of Huntington disease (HD) with respect to age, clinical onset, progression, and genetic analyses. DESIGN: Case series of people with HD or at risk (AR) for HD. SETTING: Movement disorders and medical genetics clinics. PARTICIPANTS: Volunteer sample of 50 patients with HD and 127 AR adults. MEASURES: Neuropsychological evaluation was conducted with multiple measures of cognitive function (intelligence, memory, attention, executive, spatial, language), strength, manual speed/dexterity, somatosensory function, and mood. Quantitative molecular genetic analysis by means of polymerase chain reaction was conducted on 31 patients with HD and 86 AR subjects. RESULTS: In clinical HD, cognitive impairment correlated with number of years affected but not age at onset. The linear regression had a negative intercept, suggesting impaired cognitive function by the time of onset. In AR gene carriers, lower cognitive performance correlated with more trinucleotide repeats. In clinical HD, trinucleotide repeats interacted with disease chronicity such that more repeats were associated with worse performance over time; the overall effect of this was small compared with the effect of disease chronicity alone. Except for one AR subject, mood state was not associated with cognitive performance in either patients with HD or AR subjects. CONCLUSIONS: Cognitive decline appears to start before clinical onset of HD and is correlated with the number of trinucleotide repeats. Subsequent cognitive decline is primarily a function of number of years affected, although there is evidence that the presence of more trinucleotide repeats is associated with faster deterioration.

Adolescent↗

Adult-onset subacute sclerosing panencephalitis: case reports and review of the literature.

Subacute sclerosing panencephalitis (SSPE) is mainly thought of as a disorder of childhood and adolescence and may not be readily recognized when presenting later in life. Prior reports have suggested that adult-onset SSPE may have atypical features. We have added two cases to the existing literature on adult-onset SSPE, compared them with a more classic juvenile presentation, and extensively reviewed those reports that were published after the etiological link with the measles virus had been established. Adult-onset SSPE patients present at a mean age of 25.4 years (range 20-35 years). They have a higher proportion of either negative history of measles exposure or undocumented history by the reporting authors. Those with available history of measles exposure tend to have it either earlier (younger than 3 years old) or later (after 9 years) than the usual childhood measles infection. Where the primary infection is known, unusually long measles-to-SSPE intervals have been documented, ranging from 14 to 22 years. None of the cases followed measles vaccination. Visual symptomatology was very frequent, with 8 of the 13 cases reviewed having a purely ophthalmological presentation; only 2 patients presented with behavioral changes. Although the course of the disease was progressive and fatal in the majority, there appeared to be a higher rate of spontaneous remission as compared with childhood-onset SSPE. Myoclonus, spastic hemiparesis, bradykinesia, and rigidity were the predominant motor manifestations. Neuropathology revealed cortical and subcortical gray matter involvement preferentially of the occipital lobes, thalamus, and putamen. The importance of recognizing the spectrum of potential presentations of SSPE and providing an early diagnosis will increase as more effective treatments become available.

Adolescent↗

Serotonin syndrome and the combined use of deprenyl and an antidepressant in Parkinson's disease. Parkinson Study Group.

The manufacturer of deprenyl (selegeline; Eldepryl) (Somerset Pharmaceuticals, Tampa, FL) recently advised physicians to avoid prescribing the drug in combination with an antidepressant because of potentially serious CNS toxicity that may represent the serotonin syndrome. Manifestations of the serotonin syndrome vary but may include changes in mental status and motor and autonomic function. To better estimate the frequency of the serotonin syndrome in patients with Parkinson's disease (PD) treated with deprenyl and an antidepressant, we surveyed all investigators in the Parkinson Study Group. Based on estimates provided by the 47 investigators (75%) who responded, 4,568 patients were treated with the combination of deprenyl and an antidepressant medication. Eleven patients (0.24%) were reported to have experienced symptoms possibly consistent with the serotonin syndrome. Only two patients (0.04%) experienced symptoms considered to be serious. No deaths were reported. We also reviewed all published case reports and adverse experiences reported to the U.S. Food and Drug Administration and the manufacturer of Eldepryl. Available information indicates that serious adverse experiences resulting from the combined use of deprenyl and an antidepressant medication in patients with PD are quite rare and that the frequency of the true "serotonin syndrome" is even rarer.

Aged↗

Multidisciplinary approach to management of a hereditary neurodegenerative disorder: Huntington disease.

Huntington Disease is a well known autosomal dominant inherited disease resulting in emotional problems, abnormalities of movement, and eventually dementia. It stands out as one of the most devastating illnesses, not only for its neurodegenerative progression but also for its impact on families. Care often becomes fragmented due to the person's response to symptoms and/or family breakdown. The successful interaction of health care disciplines working with Huntington Disease in our centers, namely, the family physicians, nursing, Genetics, Neurology, Psychiatry, Social Work, and Long Term Care has resulted in a comprehensive program of care for our patients and their families. This article will describe the history, structure and interaction of the multidisciplinary group. It will describe the difficulties we have overcome and offer suggestions for the implementation of similar programs for the care of people with other disorders.

Humans↗

SOD1 mutation is associated with accumulation of neurofilaments in amyotrophic lateral sclerosis.

Mutations in the Cu/Zn superoxide dismutase (SOD1) gene are found in 15 to 20% of patients with familial amyotrophic lateral sclerosis (FALS). Increased levels of neurofilament subunits in transgenic mouse models of ALS also suggests a key role for these proteins in the pathogenesis of the disease. We report the coexistence of an Ile113-->Thr substitution in exon 4 of the SOD1 gene and marked neurofilamentous pathology in the same FALS patient. These observations suggest that two mechanisms, SOD1-induced toxicity and neurofilament disruption, are acting together.

Aged↗

Relationship between trinucleotide repeats and neuropathological changes in Huntington's disease.

The discovery of the Huntington's disease (HD) gene has provided the impetus to determine the association between the triplet repeat sequences and clinical manifestations of the disease. The present study is directed toward determining the relationship between the triplet repeat sequences and severity of the neurodegenerative process. Nineteen HD postmortem cases were evaluated for neuropathological changes as well as for the number of trinucleotide repeat sequences, each in a blinded fashion. Each case was assigned a gross grade according to the scale of Vonsattel and colleagues (1985); neuronal counts were then performed on both the caudate and the putamen. For 7 of the postmortem cases, blood had been collected prior to death and was analyzed for the HD gene. For the 12 remaining cases for which blood was unavailable, DNA from the frontal neocortex and striatum was extracted from frozen or formalin-fixed paraffinized tissue and subsequently analyzed for the HD gene. When correlation was made for age at death, greater numbers of trinucleotide repeats were associated with greater neuronal loss, in both the caudate (r = 0.9641, p < 0.001) and the putamen (r = 0.9652, p < 0.001). When correction was made for disease duration, the correlation was again significant, for both the caudate (r = 0.6396, p < 0.01) and the putamen (r = 0.6710, p < 0.001). This suggests that in HD, longer trinucleotide repeat length is associated with a faster rate of deterioration and greater pathological severity. A comparison of trinucleotide repeat length in different brain regions in 4 of the HD postmortem cases associated with greater numbers of repeats consistently demonstrated fewer repeats in the cerebellum than in the frontal cortex, striatum or blood.

Adult↗

Beneficial effect of intranasal desmopressin for nocturnal polyuria in Parkinson's disease.

Patients with Parkinson's disease (PD) are known to experience autonomic nervous system dysfunction: this disruptive symptomatology includes urinary urgency, frequency, and nocturnal polyuria. Anticholinergic and tricyclic medications can be beneficial in controlling these urinary symptoms, but have unpleasant side effects in some patients. Desmopressin has been used to treat nocturnal polyuria successfully in a number of conditions, such as central diabetes insipidus, enuresis, and autonomic failure. The purpose of the present study was to assess the efficacy of desmopressin in patients with PD with significant nocturia. Eight patients were recruited into the study. They were first asked to establish a baseline of number of nocturnal voids; the patients were then prescribed the intranasal form of desmopressin and asked to continue to record the number of nocturnal voids. The five patients who completed the trial demonstrated clinically and statistically significant reductions in the frequency of nocturnal voids. One patient became hyponatremic and confused during desmopressin administration; his symptoms resolved soon after the desmopressin was discontinued. Two patients failed to complete the trial due to compliance problems. Thus, desmopressin appears to be a safe and effective medication for nocturnal polyuria in PD.

Administration, Intranasal↗

Huntington's disease: recent advances in diagnosis and management.

Huntington's Disease (HD) is a progressive degenerative disorder of the central nervous system inherited as an autosomal dominant trait. Clinically, the disorder is characterized by choreoathetosis (with age of onset typically in the late thirties or early forties) and neuropsychiatric disturbance. The striatum is particularly vulnerable to the degenerative disease process, with selective loss of medium spiny neurons and decreased levels of associated neurotransmitters, including substance P. GABA, met-enkephalin and dynorphin. Although the underlying pathophysiology is unknown, recent theories concerning pathogenesis have involved mitochondrial abnormalities and excitotoxin-mediated damage. The gene for HD has recently been discovered and characterized as an unstable CAG trinucleotide repeat sequence on the short arm of chromosome 4 (now known as IT15). The direct test now available for the HD gene has facilitated disease diagnosis, particularly for those with unclear family history or chorea of uncertain origin; presymptomatic testing is also available. Management of affected individuals is unsatisfactory as only symptomatic control is available. However, as the effect of the genetic abnormality may soon be known, specific treatment of the disorder may become available in the near future.

Chorea↗

Investigation of the potential role of genetic imprinting in Gilles de la Tourette syndrome.

Genetic imprinting refers to the phenomenon whereby the precise expression of a specific trait (or disease) may depend on the sex of the transmitting parent. The purpose of the present project was to investigate the possibility for the involvement of genetic imprinting in Tourette syndrome (TS), a disease of the central nervous system in which many cases show evidence of an autosomal dominant mode of inheritance. The justification for the study arose from the noted variable expression of the associated symptoms in TS. Through the method of chart review, information regarding sex of the transmitting parent, age of onset of motor tics, as well as associated symptoms, was gathered from patients with a clear family history of TS consistent with autosomal dominant mode of transmission. No evidence was found for genetic imprinting in TS. The potential criticisms and implications of this finding are discussed.

Child↗

Gilles de la Tourette syndrome.

Gilles de la Tourette syndrome is a neurological disorder characterized by the presence of motor and vocal tics. Other associated features include complex motor and vocal tics, obsessive compulsive behavior and attention-deficit disorder. Although initially thought to be a rare condition, it now appears that the gene for Tourette syndrome may be present in as many as one in a thousand people, and is transmitted as an autosomal dominant trait. However, many individuals carrying the gene may exhibit only minimal symptoms. Neuropathophysiology of Tourette syndrome is unknown but investigations have suggested that the cause may be an abnormality either in the dopaminergic or endorphin receptor system within the basal ganglia. Treatment of Tourette syndrome involves education and counseling of the patient and family. Medications such as neuroleptics, serotonin-reuptake inhibitors, and stimulants are available to treat the manifestations of Tourette syndrome and need to be individualized for each patient.

Humans↗

Five year study of prenatal testing for Huntington's disease: demand, attitudes, and psychological assessment.

Adult predictive and prenatal testing programmes for Huntington's disease (HD) in Canada have been available since 1986. However, the demand for prenatal testing and the reasons why some people choose not to have the prenatal test for this late onset disorder have not been well documented. In addition, the knowledge and attitudes of adult predictive testing candidates and their partners about prenatal testing are not well known nor are the psychological effects of prenatal testing well understood. As of September 1991, 425 subjects had entered the Canadian Collaborative Study of Predictive Testing and, of these, 47 subjects or their partners had become pregnant. Of this group, 14 (30%) couples requested prenatal testing, 24 (51%) couples did not want prenatal testing, and nine (19%) at risk subjects had already received a decreased risk through adult predictive testing and, therefore, were not eligible for the prenatal test. Of the 14 couples who initially requested prenatal testing, seven withdrew. Thus, demand for the prenatal test by eligible candidates was 7/38 or 18%, which is much lower than the 32 to 65% expected based on early survey data. The most frequently cited reason for declining prenatal testing was the hope that a cure would be found in time for their children. While the majority of adult predictive testing candidates (71%) in our study had accurate information about definitive prenatal testing, many (63%) did not have a correct understanding of exclusion prenatal testing. Although no serious adverse events such as suicide planning or admission to psychiatric hospital have occurred, a particular need for careful counselling was identified for those at risk candidates and their partners who have one prenatal test and feel compelled to use the test again in future pregnancies. Even though prenatal testing for HD is not requested as often originally expected, it still remains a desired option for some at risk persons and their partners.

Adult↗

Predictive testing for Huntington disease in Canada: adverse effects and unexpected results in those receiving a decreased risk.

By January 1, 1991, a total of 388 persons had enrolled in the Canadian collaborative study of predictive testing for Huntington disease (HD). Of these participants, 105 persons have been given a decreased risk result. Contrary to expectations, approximately 10% of persons with a decreased risk result have had psychological difficulties coping with their new status. Here, we describe the individual responses of 6 such persons and experimental themes emerging after following these persons for up to 2 years. Individuals who are more likely to suffer an adverse reaction to a decreased risk result include those persons who have made irreversible decisions based on the belief they would develop HD or those who had unrealistic overoptimistic expectations of the positive effects of a decreased risk result. In contrast to those receiving an increased risk result, the most vulnerable time for persons receiving a decreased risk result is between 2 and 12 months after learning the outcome. The need for assessment and counselling of participants in predictive testing programs, even when there is a decreased risk result, is emphasized.

Adult↗