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PubMed2004

Functional dyspepsia: motor abnormalities, sensory dysfunction, and therapeutic options.

Functional dyspepsia is a common condition, but as yet, the underlying etiology is unclear. In this article, upper gastrointestinal motor and sensory physiology are reviewed and the current evidence for motor and/or sensory functional abnormalities causing dyspeptic symptoms is presented. The complex interrelationship between abnormal motor activity and sensation is explored, as well as the potential roles for autonomic dysfunction and psychological state in modulating gastrointestinal sensation and motor function. Finally, based on clinical trial evidence, a treatment pathway for functional dyspepsia is suggested.

Dyspepsia↗

PubMed1997

Autonomic neuropathy predisposing to arrhythmias in hemodialysis patients.

Arrhythmias are frequent among the dialysis population and can cause symptoms of palpitations or dizziness. Since autonomic disturbances are known to cause an increased arrhythmogenic stimulus, we questioned whether the presence of central autonomic neuropathy increased the frequency of arrhythmias as identified by 24-hour electrocardiographic monitoring in dialysis patients. Seventy-one patients were randomly chosen from patients established on dialysis in two centers. The mean age of the patients was 71.3 years (median age, 67 years) and median duration on dialysis was 17.0 months (range, 1 to 175 months). Four patients had diabetes. Each patient was tested for autonomic control of blood pressure and heart rate, and underwent Holter electrocardiographic monitoring, commencing 30 minutes before dialysis, for a 24-hour period. The tapes were then analyzed for ventricular and atrial rhythm changes. There was a significantly increased incidence of arrhythmias in individuals with abnormal blood pressure responses (P = 0.005), heart rate responses (P = 0.01), and combined blood pressure and heart rate responses (P = 0.004). We conclude that patients with autonomic dysfunction had an increased frequency of arrhythmias during dialysis.

Adult↗

PubMed2003

[On the subject of the cyclic vomiting syndrome].

The cyclic vomiting syndrome is defined by episodes of vomiting lasting from hours to days with free intervals between episodes. Various symptoms can be associated with vomiting: nausea, abdominal pain, photophobia, fever, pallor, dehydratation, excess salivation, social withdrawal. Some factors often precipitate the crisis: infection, psychological stresses, menstruation. Excluding a medical condition, especially a gastro-intestinal or a neurological disease is compulsory for the diagnostic of cyclic vomiting syndrome. The cyclic vomiting syndrome shares many common features with migraine including treatment. Due to negative paraclinical testing, a psychiatric disease is often suspected in these children. Pathophysiology of cyclic vomiting syndrome is unknown. As for migraine, mitochondrial and ionic channels abnormalities are thought to play a role. Overactivation of hypothalamic-pituitary-adrenal axis and autonomic dysfunction seem to be involved too. Three clinical vignets will illustrate these aspects.

Adolescent↗

PubMed2006

Cardiovascular autonomic function tests in cluster headache.

While facial autonomic signs are prominent during cluster headache (CH) attacks, cardiovascular autonomic changes have been described in few CH patients. Cardiovascular autonomic function tests (AFT) can be used to assess general autonomic function in CH patients in different stages of the disease. We aimed to assess whether general autonomic function is changed in CH patients during a cluster period. AFT was performed both during a cluster period, but outside an actual attack, and outside a cluster period in 18 patients. Heart rate variability was studied at rest, during deep breathing, after standing up and during a Valsalva manoeuvre. Blood pressure (BP) changes were recorded at rest, during standing up and during sustained handgrip. Measurements during and outside the cluster period were compared using the paired t-test. AFT measurements revealed no significant differences between the two measurements, except for diastolic BP in rest, which was higher during the cluster period [80.3 (SD 12.2) vs. 74.8 (SD 9.0), P = 0.04]. Autonomic dysfunction during a cluster period, but outside an attack, does not include systemic cardiovascular control.

Autonomic Nervous System↗

PubMed2005

Finger cold-induced vasodilatation, sympathetic skin response, and R-R interval variation in patients with progressive spinal muscular atrophy.

To elucidate autonomic function in spinal muscular atrophy, we evaluated finger cold-induced vasodilatation, sympathetic skin response, and R-R interval variation in 10 patients with spinal muscular atrophy: 7 of type 1, 2 of type 2, and 1 of type 3. Results of finger cold-induced vasodilatation, sympathetic skin response, and R-R interval variation were compared with those of healthy children. Finger cold-induced vasodilatation was abnormal in 6 of 10 patients with spinal muscular atrophy; it was normal in the healthy children. The mean sympathetic skin response latency and amplitude did not differ significantly from those of the healthy children. Amplitudes of sympathetic skin response to sound stimulation were absent or low in all six patients with spinal muscular atrophy. No significant difference was found in the mean R-R interval variation of patients with spinal muscular atrophy and healthy children. Results show that some patients with spinal muscular atrophy have autonomic dysfunction, especially sympathetic nerve hyperactivity, that resembles dysfunction observed in amyotrophic lateral sclerosis.

Adolescent↗

PubMed2000

[Diffuse Lewy body disease searched out from 114 patients with parkinsonism].

From 114 patients who had been previously diagnosed as Parkinson's disease, we diagnosed six cases as clinically definite "diffuse Lewy body disease (DLBD)" according to McKeith's criteria with more strict modifications. Besides a central feature, dementia, and core features including parkinsonism, fluctuating cognition, and recurrent visual hallucinations, the patients presented some of supportive features, that is, repeated falls (4 cases), syncope (5 cases), and transient loss of consciousness (all cases). Autopsy, which was performed in 2 of the cases, revealed Lewy bodies in various nervous tissues including autonomic nervous systems in both cases. 7 cases of probable DLBD and 8 cases of possible DLBD, which lacked fluctuating cognition and/or visual hallucinations, demonstrated neither of repeated falls, syncope, nor transient loss of consciousness. Episodes of these supportive features, which seem to be associated with autonomic dysfunctions and/or fluctuating cognition, should be important in the differential diagnosis of DLBD.

Adult↗

PubMedDate not supplied

Sympathetic skin response in patients with amyotrophic lateral sclerosis.

To determine a possible involvement of the autonomic nervous system in amyotrophic lateral sclerosis (ALS), measurement of the sympathetic skin response (SSR) was performed in 15 patients with definite ALS. Findings were compared with those in 20 normal controls. In ALS patients the mean SSR latencies recorded from the palms and soles were both significantly prolonged (p < 0.05) and the amplitudes were reduced as compared with normal persons. In 5 patients, SSR potentials were completely lacking in one or even more extremities. Our data strongly suggest subclinical involvement of the autonomic nervous system in ALS as assessed by the SSR response. In our patients the extent of autonomic dysfunction was not related to the stage or the duration of disease.

Adult↗

PubMed1976

Amplitude of pupillary contraction as a function of intensity of illumination in schizophrenia.

When the amplitude of pupillary contraction of normal, healthy adults was binocularly recorded as a function of increasing intensity of light-stimulation, a linear relationship was found between the amplitude and log intensity. Schizophrenic patients deviated significantly from this systematic response pattern in two ways. One group of patients (35%) manifested the same pupillomotor threshold as the normals, however, as the intensity of light was systematically increased mean amplitude and rate of pupillary contraction fell below that evidenced by normals. Another group of patients (65%) were distinguished by an abnormal pupillomotor threshold, specifically requiring an increase of one log intensity unit for the elicitation of a recordable pupillary contraction. Moreover, as the light intensity increased, the mean amplitude of contraction was significantly attenuated at all intensities below that of the normals and of the schizophrenics who manifested a normal pupillomotor threshold. In addition, it was found that the average diameter of the dark-adapted pupil was smaller in both groups of patients as compared to the healthy adults, although there was no difference between the patient groups on the variable. As pupillary reactivity to stress in normals is characterized by an increase in the diameter of the dark-adapted pupil representing increased sympathetic outflow and by a reciprocal increase in the diameter of the light-adapted pupil representing increased supranuclear inhibition, the results of the study do not support the assertion that schizophrenics are hyperaroused. It is suggested schizophrenia may be considered a tonic autonomic dysfunctional state of mock-arousal characterized by either abnormally high levels of central supranuclear inhibition or by defective sympathetic outflow, or both.

Adult↗

PubMed1982

Autonomic nervous system dysfunction and impotence in uremia.

The relationship between abnormalities in nocturnal penile tumescence (NPT) and autonomic function, measured by the Valsalva maneuver, was evaluated in 25 uremic patients and 22 normal subjects. NPT in uremic patients (45 +/- 6.8 min/night) was lower (p less than 0.01) than in normals (85 +/- 10.4 min/night). Valsalva ratio in uremics (1.58 +/- 0.07) was also lower (p less than 0.01) than in normal subjects (2.05 +/- 0.11). NPT and Valsalva ratio were significantly correlated in uremic patients (r = 0.62, p less than 0.01). The 12 uremic patients with abnormal Valsalva maneuver had NPT of 22 +/- 5.2 min/night, a value lower (p less than 0.01) than that (67 +/- 8.7 min/night) observed in the 13 uremic patients with normal Valsalva maneuver. There was also a significant correlation (r = 0.56, p less than 0.05) between the Valsalva ratio and the frequency of intercourse per month in the uremic patients, who had steady and active sexual partners. The data suggest that a dysfunction of the autonomic nervous system may be an important factor in the genesis of erectile abnormalities in patients with uremia.

Adult↗

PubMed1975

Acute autonomic neuropathy. Its occurrence in infectious mononucleosis.

A 13-year-old girl with acute onset of symptoms limited to autonomic dysfunction was found to be suffering from infectious mononucleosis. With symptomatic therapy, improvement gradually occurred over a period of seven months. The documentation of this case widens the spectrum of disorders to be considered as a cause of so-called acute pandysautonomia or autonomic neuropathy.

Adolescent↗

PubMed1988

Subnormal pancreatic polypeptide and epinephrine responses to insulin-induced hypoglycemia identify patients with insulin-dependent diabetes mellitus predisposed to develop overt autonomic neuropathy.

Sixteen patients with insulin-dependent diabetes mellitus with no current evidence of autonomic dysfunction underwent an insulin tolerance test during which plasma pancreatic polypeptide and epinephrine responses were determined. Compared to 11 age- and weight-matched nondiabetic volunteers, 9 diabetic subjects had subnormal plasma pancreatic polypeptide responses (n = 6) or plasma epinephrine responses (n - 8). When autonomic function was reassessed 2 to 3 years later by standard cardiovascular reflex tests and clinical examination, 8 of 9 diabetic subjects with subnormal hormonal responses to hypoglycemia developed either abnormal cardiovascular reflexes (6 of 9) or overt symptoms consistent with diabetic autonomic neuropathy (6 of 9), whereas none of the subjects with previously normal plasma pancreatic polypeptide and epinephrine responses did (P less than 0.01). Diminished pancreatic polypeptide and epinephrine responses to hypoglycemia can predict the development of overt autonomic neuropathy in patients with insulin-dependent diabetes mellitus; identification of patients with a predilection to develop autonomic neuropathy may permit earlier treatment.

Adult↗

PubMedDate not supplied

To stand on one's own legs.

A fundamental human expectation is to stand upright. This exposes the cardiovascular system to gravitational forces, with a fall in pressure above heart level exposing organs such as the brain to impaired perfusion if adequate adaptive mechanisms are not activated. The autonomic nervous system plays an important role in the initial response to standing upright, and can be affected by several disorders, some rare, some common. Autonomic failure can result in orthostatic hypotension with hypoperfusion of vital organs, causing a variety of symptoms including syncope. Thus, it is important to recognise orthostatic hypotension, determine its aetiology, evaluate and treat it. Intermittent autonomic dysfunction (such as neurally mediated syncope without chronic neurogenic failure) also results in falls and syncope; various forms include the 'common faint' (vasovagal syncope) and carotid sinus hypersensitivity (especially in the elderly). Orthostatic intolerance without orthostatic hypotension is increasingly recognised as due to an autonomic disturbance. New techniques are helping to unravel the functional anatomy of cerebral autonomic centres and their pathways in the causation of orthostatic intolerance.

Autonomic Nervous System↗

PubMed1997

Autonomic involvement in Wilson's disease: a study of sympathetic skin response and RR interval variation.

Autonomic nervous system involvement in Wilson's disease (WD) was studied in 25 patients by sympathetic skin response (SSR) and RR interval variation (RRIV). The control group consisted of age-matched healthy subjects. Palmar SSRs were obtained by central activation from median nerve stimulation and by activation of sympathetic trunk from magnetic stimulation of the neck. Electric SSRs were prolonged in 11 patients and absent in 2; magnetic SSRs were delayed in 4 and absent in 1; and the sympathetic central conduction time was prolonged in 3. The mean latencies and mean central conduction of the SSRs were all significantly prolonged in WD when compared to the control group. On the other hand, parasympathetic function was abnormal in 3 patients only during forced deep breathing, and as a group only mean D% was significantly reduced. The present findings suggest that autonomic dysfunction may occur in WD, and that sympathetic function is predominantly affected, mainly due to central involvement.

Adolescent↗

PubMed2003

Autonomic function and autoantibodies to autonomic nervous tissues at follow-up in a cohort of young patients with type 1 diabetes. Effects of serum from diabetic patients on human adrenergic cells.

Recent studies have linked autoimmunity to nervous tissue structures and diabetic autonomic neuropathy. To evaluate prospectively the early stage of type 1 diabetes and the natural history of this association, we monitored the autonomic function and the presence of autoantibodies (Ab) to sympathetic and parasympathetic nervous structures in a cohort of 92 diabetic adolescent patients, recruited and followed-up after 40+/-3 months. The presence of circulating Ab and their ability to activate complement was also assessed using a human adrenergic neuroblastoma cell line, and the effect of patients' sera on these cells was evaluated by different methods assessing cytotoxic effects and apoptosis. Thirty-nine percent of the Ab-positive patients had one abnormal test (p=0.07 vs. Ab-negative patients). Serum from four patients positive for anti-cervical ganglia Ab showed positive staining of neuroblastoma cells and displayed ability to activate complement. Serum from two adolescent patients with anti-cervical ganglia and anti-neuroblastoma cells Ab, induced cytotoxic effects and damaged the plasma membrane of the neuroblastoma cells. Moreover, sera from two adult patients with overt autonomic neuropathy, used as positive controls, induced apoptosis of these cells, assessed by TUNEL. Our data indicate that symptomatic autonomic neuropathy is not characteristic of young diabetic patients, but that autoantibodies to autonomic structures are present and persist in the first 20 years of disease, possibly associated with subtle autonomic dysfunction and cytotoxic effect on sympathetic cells.

Adolescent↗

PubMed2001

Importance of Rett syndrome in child neurology.

The syndrome of brain atrophy in girls described by Andreas Rett in 1966 [Rett, Wien Klin Wochenschr, 1966;116:723-726] was brought to the attention of the English-speaking world by Hagberg et al. in 1983 [Hagberg et al., Ann Neurol, 1983;14:471-479]. Four clinical stages after the age of 6 months were described in classical cases of Rett syndrome (RS), namely early onset stagnation at 6 months to 1(1/2) years, the rapid destructive stage at 1-3 years, the pseudo-stationary stage from pre-school to school years, and the late motor deterioration stage at 15-30 or more years. The rapid destructive stage causes profound dementia with loss of speech and hand skills, stereotypic movements, ataxia, apraxia, irregular breathing with hyperventilation while awake, and frequently seizures. Most cases are isolated in their families, apart from identical twins. However, linkage studies in rare familial cases suggested a critical region at Xq28. In 1999 American investigators found several mutations in the X-linked gene MECP2 encoding Methyl-CpG-binding protein 2 in a proportion of Rett patients. The protein MeCP2 can bind methylated DNA and when mutated may interfere with transcriptional silencing of other genes and result in abnormal chromatin assembly. Many different mutations of the protein are being studied in humans and in mice. Neuropathological studies have shown decreased brain growth and decreased size of individual neurons, with thinned dendrites in some cortical layers, and abnormalities in substantia nigra, suggestive of deficient synaptogenic development, probably starting before birth. Electrophysiology demonstrates progressively abnormal electroencephalograms (EEG) in the first three stages of the syndrome, with some subsequent improvement and occurrence of pseudoseizures. Neurometabolic factors are discussed in detail, particularly reduced levels of dopamine, serotonin, noradrenaline and choline acetyltransferase (ChAT) in brain, also estimation of nerve growth factors, endorphin, substance P, glutamate and other amino acids and their receptor levels. Autonomic dysfunction is described, particularly reduced vagal and overactive sympathetic activity. Neuro-imaging may be required for further investigation, as shown in the differential diagnosis.

Adolescent↗

PubMed2003

Cardiovascular autonomic neuropathy associated with carotid atherosclerosis in Type 2 diabetic patients.

AIMS: To clarify if cardiovascular autonomic neuropathy is associated with carotid artery atherosclerotic plaques in Type 2 diabetic patients. METHODS: Cardiovascular autonomic nerve function was related to carotid artery ultrasound in 61 Type 2 diabetic patients 5-6 years after diagnosis of diabetes. RESULTS: Cardiovascular autonomic neuropathy [abnormal age corrected expiration/inspiration (E/I) ratio or acceleration index (AI)] was found in 13/61 (21%) patients. Patients with cardiovascular autonomic neuropathy showed increased degree of stenosis in the common carotid artery (24.6 +/- 13.2% vs. 14.7 +/- 9.2%; P = 0.014) and a tendency towards a higher plaque score (4.0 +/- 1.7 vs. 3.2 +/- 1.6; P = 0.064). Controlled for age, AI correlated inversely with degree of stenosis (r = -0.39; P = 0.005), plaque score (r = -0.39; P = 0.005), and mean (r = -0.33; P = 0.018) and maximum (r = -0.39; P = 0.004) intima-media thickness in the common carotid artery. In contrast, E/I ratio correlated only slightly with mean intima-media thickness in the common carotid artery (r = -0.28; P = 0.049). CONCLUSIONS: Cardiovascular autonomic neuropathy was associated with carotid atherosclerosis in Type 2 diabetic patients. Abnormal E/I ratios reflect efferent structural damage to parasympathetic nerves whereas abnormal AI reflects afferent autonomic dysfunction possibly due to impaired baroreceptor sensitivity secondary to carotid atherosclerosis.

Adult↗

PubMed2006

Reactive oxygen species and autonomic regulation of cardiac excitability.

Sympathetic hyper-activity and diminished parasympathetic activity are a consequence of many primary cardiovascular disease states and can trigger arrhythmias. Emerging evidence suggests that reactive oxygen species (ROS) including nitric oxide, superoxide, and peroxynitrite may contribute to cardiac sympathovagal imbalance in the brainstem, peripheral neurons, and in cardiomyocytes since all experience increased oxidative stress as a result of cardiac disease processes and aging. This article reviews the roles of ROS in autonomic dysfunction and arrhythmia. In addition, novel research directed toward finding targets for modulating sympathovagal balance in cardiac disease is discussed.

Action Potentials↗

PubMed1977

Hypothalamic symptomatology and its relationship to diencephalic tumor in childhood.

Autonomic dysfunction in a child may present confusing clinical phenomena which mimic other diseases. Various clinical manifestations were seen during the 6-year course of a child with an astrocytoma of the hypothalamus. These ranged from the initial features of the diencephalic syndrome of infancy to autonomic seizures with striking paroxysms of hypertension, tachycardia, and sweating. Disturbances in hormonal regulation and gastrointestinal abnormalities were possibly related to the autonomic disturbance. The mechanisms for these findings were poorly understood. We conclude that a diencephalic lesion should be suspected in any child exhibiting such findings.

Astrocytoma↗