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PubMed1992

Neurological risk profile in organic erectile impotence.

Thirty men who presented with erectile impotence to the urological department underwent a thorough urological, angiological, and neurological examination with complementary neurophysiological tests of somatosensory and sympathetic and parasympathetic function. Most had vascular and neurological abnormalities. Clinical findings and electrophysiological tests for autonomic dysfunction had the highest yield of abnormal results. Nerve conduction studies and pudendal nerve somatosensory evoked potentials were far less informative. The lack of correlation between vascular and general neurological abnormalities emphasises that patients must be screened for both vascular and neurological dysfunction to prevent unrewarding vascular operation in impotent men.

Adult↗

PubMed2002

Pupil signs of sympathetic autonomic neuropathy in patients with type 1 diabetes.

OBJECTIVE: Pupillary autonomic neuropathy is considered an early sign of the development of systemic autonomic neuropathy. Sympathetic denervation is related to the duration of diabetes and the development of systemic autonomic dysfunction. We investigated pupil responsiveness to directly and indirectly acting sympathomimetics in type 1 diabetic patients with and without long-term complications, defined as cardiac autonomic neuropathy (CAN), peripheral sensomotor neuropathy, retinopathy, and nephropathy, and in healthy subjects. RESEARCH DESIGN AND METHODS: A total of 47 randomly chosen type 1 diabetic patients and 20 healthy subjects were selected for this study. Patients were divided into groups determined by whether they had long-term diabetic complications. Pharmacological tests were performed with cocaine 4%, epinephrine 1%, and pholedrine 5% eye drops. Horizontal pupil diameter (HPD) was measured at the beginning of the pharmacological tests and at defined time points after instillation of the eye drops. RESULTS: Statistical analysis showed a significantly smaller HPD in the patients before instillating eye drops (P = 0.011). In particular, the HPD was significantly smaller in the patient group without CAN when compared with healthy subjects (P = 0.004). Maximal cocaine reaction was diminished in the complication group (P < 0.001). Epinephrine test, visual acuity, ocular pressure, and HbA(1c) did not differ in patients with or without long-term complications. The noncomplication group showed no significant differences in pupillary responses as compared with healthy subjects. The complication group showed a smaller HPD (P = 0.022), reduced pupillary responses in the cocaine (P = 0.037) and pholedrine tests (P < 0.001), and anisocor pupil sizes after instillation of the eye drops (P = 0.034). CONCLUSIONS: Our results clearly show that sympathetic denervation does exist in the pupil of diabetic patients and that it can be rapidly assessed using the cocaine test. These data and the results of the epinephrine test suggest a mixed pre- and postganglionic dysfunction of the sympathetic plexus. The significant smaller HPD in patients without CAN compared with that of healthy subjects could be a sign for early involvement of the pupil function before cardiac manifestation of systemic autonomic diabetic neuropathy.

Adult↗

PubMed2005

Heart rate turbulence and left ventricular ejection fraction in Chagas disease.

AIMS: Chagas disease patients often present premature ventricular complexes (PVCs), depression of left ventricular ejection fraction (LVEF) and autonomic dysfunction, which is generally evaluated by heart rate variability (HRV) analysis. As frequent PVCs may complicate HRV computation, we measured heart rate turbulence (HRT) and evaluated the correlation between ejection fraction and HRT or HRV in Chagas disease. METHODS: We studied 30 patients (47+/-11 years, 20 men) with Chagas cardiomyopathy and left ventricular dilatation who underwent clinical evaluation, ejection fraction (EF: 45+/-14%) determination and 24-h Holter monitoring (median PVC=1781). In all patients, the standard deviation of normal RR intervals (SDNN), the square root of the mean square differences of successive RR intervals (RMSSD) and values of turbulence onset (TO) and turbulence slope (TS) were calculated. RESULTS: HRT indices were independent of mean RR interval and presented high correlation with EF: TO (-0.11+/-0.01%, r=-0.60, P<0.001) and TS (5.8+/-3.7 ms/RR-interval, r=0.73, P<0.001). Of HRV parameters, only SDNN, corrected for mean RR interval, showed a weak but not significant correlation with EF (r=0.41). The comparison of HRT/EF and HRV/EF correlation coefficients, indicated the presence of a significant difference (P=0.017). CONCLUSIONS: HRT indices appear to correlate better with EF than SDNN in Chagas disease. Thus, an analysis based on heart rate transient adaptation seems to perform better than HRV in detecting the autonomic alterations that parallel left ventricular dysfunction in Chagas disease patients. The high number of PVCs observed in these patients further support the use of HRT methodology.

Adult↗

PubMed1998

Relationship between autonomic function and progression of renal disease in diabetic proteinuria: clinical correlations and implications for blood pressure control.

The objective of this study was to test the relationship between neurologic and microvascular complications of type 1 diabetes mellitus. It was hypothesized that the mechanisms operative in autonomic dysfunction seen in diabetic patients with microangiopathy play a role in the rapidity of progression to renal failure. Twenty-six type 1 diabetic patients with proteinuria were studied with computerized monitoring of heart rate variation during timed ventilation, assumption of upright posture, and Valsalva maneuver and with 24-h ambulatory blood pressure monitoring at baseline. Renal function was evaluated over the ensuing 12 months of intensive insulin therapy. Blood pressure was treated so as to achieve consistent 24-h readings < 140/90 mm Hg. Angiotensin converting enzyme inhibitors were the preferred antihypertensive agents. Serial serum creatinine concentrations were compared using repeated measures analysis of variance. Over 12 months there were no significant serum creatinine changes for any autonomic test group with normal results at baseline. Groups with abnormal autonomic results at baseline demonstrated statistically significant increases in serum creatinine over 12 months compared to their baseline. Of the tests, Valsalva separated groups of patients with similar degrees of baseline renal impairment. Each of the sympathetic plus Valsalva combinations demonstrated a significant difference in progression of serum creatinine increase over 12 months. In each instance, if both sympathetic and Valsalva results were abnormal, there was a statistically significant increase in serum creatinine over 12 months when compared to groups in which one or both test results were normal. There is a relationship between autonomic function and the progression of renal dysfunction. The inability to vary the heart rate to a Valsalva maneuver identifies a degree of parasympathetic dysfunction that permits unopposed sympathetic tone, heralding more rapid renal destruction. A simple inexpensive bedside laboratory test discerned a relatively low-risk group of diabetic patients with proteinuria that demonstrated no deterioration in renal function over 12 months. When the Valsalva maneuver was markedly abnormal the presence of a mean arterial pressure > 100 mm Hg was associated with a greater likelihood of rapid renal deterioration. This group at higher risk of renal deterioration should undergo aggressive lowering of mean arterial blood pressure to < 95 mm Hg.

Adult↗

PubMed1991

Radiation therapy in metastatic spinal cord compression. A prospective analysis of 105 consecutive patients.

One hundred thirty consecutive patients with metastatic spinal cord compression (MSCC) were entered in a therapeutic protocol in which radiation therapy (RT) played the main role. When MSCC is diagnosed by clinical-radiologic methods such as myelography with or without computed tomography (CT) or magnetic resonance imaging (MRI), steroids are given and RT treatment started within 24 hours. When diagnostic doubts exist or stabilization is necessary, surgery precedes RT. Chemohormonal potentially responsive tumors are also treated with chemotherapy or hormonal therapy. Twelve patients (9.2%) underwent surgery plus RT, and 118 (90.8%) received RT alone. Thirteen (11%) early death patients were not evaluable. The 105 evaluable cases that received RT alone were analyzed. Median follow-up was 15 months (range, 4 to 38 months). Response among patients with back pain was 80%. In cases with motor dysfunction, 48.6% improved, and in 33 of 105 patients (31.4%) without motor disability there was no deterioration. Forty percent of patients with autonomic dysfunction responded to RT. Median survival time was 7 months with a 36% probability of survival for 1 year. The median duration of improvement was 8 months. The most important prognostic factor was early diagnosis. Radiosensitivity of tumor was only important in paraparetic patients in predicting response to RT. Complete myelographic block significantly diminished response to RT. Vertebral collapse did not influence response or survival.

Adult↗

PubMed2002

Serum erythropoietin levels may be inappropriately low in the acute neuropsychiatric porphyrias.

BACKGROUND: Patients with the acute porphyrias may develop renal failure and autonomic dysfunction. Renal damage and sympathetic failure may both cause erythropoietin (EPO) deficiency. In this study, we have investigated serum erythropoietin levels and autonomic function in patients with acute porphyria in clinical remission. METHODS: Serum erythropoietin levels and the corresponding haemoglobin (Hb) were assayed in 31 patients with acute porphyria and were compared to 15 type 1 diabetic patients with autonomic neuropathy, 23 patients with iron-deficiency anaemia and 18 healthy individuals. RESULTS: 9 out of 31 porphyric patients showed a normochromic normocytic anaemia with normal ferritin levels. Three patients had borderline-raised serum creatinine levels, and one of them was anaemic. Autonomic function was investigated in seven patients, six of them being anaemic, and the results were normal. Patients with iron-deficiency anaemia showed the expected increase in serum erythropoietin levels in response to a decreasing haemoglobin (r=-0.86, p<0.001). Patients with porphyria had inappropriately low serum erythropoietin levels for the degree of anaemia compared to iron-deficiency patients (p<0.001) although there was still a significant increase in serum erythropoietin with decreasing haemoglobin levels (r=-0.46, p=0.01). In contrast, diabetic autonomic neuropathy patients demonstrated a significant decrease in serum erythropoietin with decreasing Hb levels (r=+0.53, p=0.05). CONCLUSIONS: Patients with acute porphyria may have inappropriately low levels of EPO. In contrast to the diabetic patients, this does not appear to be due to autonomic neuropathy but it may reflect mild renal tubular impairment.

Adult↗

PubMed2004

Autonomic cardiovascular responses are impaired in women with irritable bowel syndrome.

GOALS: This study characterizes cardiovascular autonomic function in women with irritable bowel syndrome (IBS), using standardized techniques. BACKGROUND: Autonomic dysfunction is believed to contribute to abnormal gastrointestinal motility and visceral hypersensitivity in IBS. There is mounting evidence of generalized impairment of autonomic activity in patients with IBS. STUDY: Thirty women aged 39 years (95% C.I. 25-53 years) diagnosed with IBS, and 30 age-matched healthy women were studied. The ratio of low frequency to high frequency heart rate variability domains (LF:HF ratio) was used to represent cardiac sympathovagal activity, and orthostatic testing and sustained isometric handgrip exercise were used as sympathetic stimuli. Parasympathetic activity was represented by the expiratory to inspiratory R-R interval (E:I) ratio during deep breathing at 6 minutes. RESULTS: LF:HF responses to handgrip exercise (316%, C.I. 134% to 498% vs. 107%, C.I. 15% to 153%; P < 0.05) and orthostatic testing (648%, C.I. 520% to 904% vs. 330%, C.I. 140% to 520%; P < 0.05) were higher in IBS patients than controls, and the E:I ratio was significantly lower (1.47, C.I. 1.33-1.61 vs. 1.20, C.I. 1.14-1.26; P < 0.01). CONCLUSIONS: Autonomic cardiovascular function is impaired in IBS, manifest as attenuated cardio-vagal tone, and relative sympathetic excess during stimulated conditions.

Adolescent↗

PubMed1998

Detrusor areflexia in a patient with myasthenia gravis.

Myasthenia gravis (MG) is a common neuromuscular disorder, however, voiding dysfunction in conjunction with MG is rare. A review of the literature yielded only 7 prior reports of such a combination. Most of the reported cases involved incontinence in males which developed after a transurethral resection of the prostate. Only 3 cases described de novo voiding dysfunction. We report a fourth patient. In all 4 cases of de novo dysfunction, the voiding problem either heralded a new diagnosis of MG or an exacerbation of the disease process. It is hypothesized that autonomic dysfunction in patients with MG might indicate a unique subset with a worse prognosis.

Adult↗

PubMed2006

Cardiovascular disease in HIV infection.

Cardiovascular disease has been well documented in patients with Human Immunodeficiency Virus infection, especially after the introduction of highly active antiretroviral therapy. At present, HIV infection is one of the leading causes of acquired cardiovascular disease including heart failure. Some of the changes observed in these patients include left ventricular systolic dysfunction, dilated cardiomyopathy, congestive heart failure, myocarditis, lipodystrophy, dyslipidemia, insulin resistance, accelerated atherosclerosis including myocardial infarction, prothrombotic state, pericardial effusion, pulmonary hypertension, autonomic dysfunction, and malignancy. This article summarizes the main findings in the principal HIV-associated cardiovascular manifestations in order to stimulate its early recognition so helping in early intervention and therapy.

Cardiovascular Diseases↗

PubMed1989

Autonomic neuropathies affecting the lower extremities.

The autonomic nervous system is a diffuse network that is primarily under involuntary control. This article described the functional anatomy of the autonomic nervous system, which is essential in understanding the disease entities that affect the lower extremity. Autonomic dysfunction of the sympathetic system is primarily affected and includes those syndromes involving the sweat glands and the blood vessels. Abnormalities of autonomic function in the lower extremity in three prominent neuropathies has also been presented.

Autonomic Nervous System↗

PubMed1997

Heart rate variability in patients with secondary amyloidosis.

Heart rate variability (HRV) is increasingly being used to evaluate the function of the autonomic nervous system. Although autonomic dysfunction has been described in primary amyloidosis patients, this has not been established for patients with secondary amyloidosis. This study examines the autonomic function of 23 biopsy-proven secondary amyloidosis patients (10 male, 13 female) and compares it with 19 healthy (8 male, 11 female) sex- and age-matched controls (Group III), using frequency- and time-domain HRV analysis. The study group was further divided according to renal function; Group I (14 nonuremic patients with serum creatinine level < 1.4 mg/dl) and Group II (9 uremic patients with serum creatinine level > 1.4 mg/dl). In time domain analysis, standard deviation and mean of the standard deviation of all normal R to R intervals, and standard deviation of the average normal R to R interval were significantly lower in Groups I and II as compared to Group III. In frequency domain analysis, low frequency power (LF), representing sympathetic function, was significantly lower in Groups I and II as compared to Group III, but high frequency power (HF), representing parasympathetic function, and the LF/HF ratio, as an index of sympathovagal balance, were not different among the groups. In conclusion, in patients with secondary amyloidosis, sympathetic components of heart rate variables decreased before the onset of uremia and the change became more prominent with the appearance of uremia despite not reaching statistical significance.

Adult↗

PubMed1981

[A case of primary orthostatic hypotension of the Bradbury-Eggleston type].

A patient with idiopathic orthostatic hypotension not accompanied by other neurologic disorders was examined. Pulmonary function tests demonstrated the failure of the autonomic innervation of airways. A syndrome of chronic primary alveolar hypoventilation was present, with the vocal cord paralysis. The symptoms of neurogenic bladder were also present. While recumbent, the patient had low levels of plasma norepinephrine, that failed to increase after standing and exercising. During Kaplan-Silah test the patient was proved to be supersensitive to intravenously administered norepinephrine and angiotensin. The finding was consistent with the view of peripheral denervation. The syndrome of orthostatic hypotension and other symptoms referable to peripheral autonomic dysfunction, without evidence of central nervous system involvement appears to represent a clinical entity distinct from the Shy-Drager syndrome. It can be defined Bradbury-Eggleston syndrome.

Autonomic Nervous System Diseases↗

PubMed2006

Metabolic consequences of exercise-associated autonomic failure.

Type I diabetes mellitus patients who tightly control blood glucose levels toward normal have increased frequency of hypoglycemia, a major barrier to physical activity. This article presents the hypothesis that dysfunctional autonomic regulation of metabolism after recent bouts of exercise or hypoglycemia contributes to exercise-induced hypoglycemia in these patients.

Autonomic Nervous System↗

PubMed1999

Vascular abnormalities in acute reflex sympathetic dystrophy (CRPS I): complete inhibition of sympathetic nerve activity with recovery.

BACKGROUND: Reflex sympathetic dystrophy/complex regional pain syndrome type I (RSD/CRPS I) is a painful neuropathic disorder that may develop as a disproportionate consequence of a trauma affecting the limbs without overt nerve injury. Clinical features are spontaneous pain, hyperalgesia, impairment of motor function, swelling, changes in sweating, and vascular abnormalities. OBJECTIVE: To investigate pathophysiological mechanisms of vascular abnormalities in RSD/CRPS I. DESIGN: Case study. SETTING: Autonomic test laboratory at a university hospital. PARTICIPANTS: A patient with an early stage of RSD/ CRPS I of the upper limb and 2 healthy control subjects. INTERVENTIONS: Cutaneous sympathetic vasoconstrictor innervation was assessed by measuring cutaneous blood flow (laser Doppler flowmetry) and skin temperature (infrared thermometry). To quantify sympathetic vasoconstrictor function, phasic (induced by deep inspiration) and tonic (induced by controlled thermoregulation) sympathetic reflexes were analyzed. Venous norepinephrine levels were determined bilaterally. The same tests were performed in the controls after induction of cutaneous antidromic vasodilation produced by histamine dihydrochloride application. MAIN OUTCOME MEASURE: Sympathetic cutaneous vasoconstrictor function in RSD/CRPS 1. RESULTS: Two weeks after the onset of RSD/CRPS I, skin temperature on the affected side was higher (close to core body temperature) than on the contralateral side at room temperature and during controlled thermoregulation, indicating maximal vasodilation. Phasic and tonic stimulation of cutaneous vasoconstrictor neurons did not induce a decrease of skin blood flow or temperature on the affected side but were normal on the contralateral side. Venous norepinephrine levels were lower on the affected side. Parallel to clinical improvement, loss of vasoconstrictor function completely recovered within weeks. Results of investigations in healthy subjects ruled out the possibility that antidromic vasodilation caused by activation of nociceptive afferents is responsible for the complete depression of sympathetic vasoconstrictor reflexes. CONCLUSIONS: Demonstrated for the first time is a complete functional loss of cutaneous sympathetic vasoconstrictor activity in an early stage of RSD/CRPS I with recovery. The origin of this autonomic dysfunction is in the central nervous system.

Autonomic Nervous System↗

PubMed1993

Ondine's curse and neurally mediated syncope--a new and important association.

A 6-year-old boy with congenital central hypoventilation syndrome (Ondine's curse) presented with presyncope. Investigation revealed a diagnosis of neurally mediated syncope. This previously unreported association provides strong evidence that autonomic dysfunction is implicated in both these conditions.

Autonomic Nervous System↗

PubMed1996

[Interaction of chagasic autoantibodies with the third extracellular domain of the human heart muscarinic receptor. Functional and pathological implications].

Herein we demonstrate by ELISA and immunoblotting the presence in the sera of chagasic patients of circulating autoantibodies against the third extracellular domain of human muscarinic acetylcholine receptors by using a synthetic peptide corresponding to the sequence 169-192 of the receptor. Immunoaffinity purified antipeptide antibodies displayed cardiac muscarinic activity as decreased contractility and cAMP production and increased cGMP levels. These effects were specifically blocked by the synthetic peptide and by atropine. A strong association between the existence of circulating autoantibodies and the presence of dysautonomia was shown, making these autoantibodies an appropriate marker of heart autonomic dysfunction.

Adult↗

PubMed1998

Clinical and electrophysiologic attributes as predictors of results of autonomic function tests.

Autonomic dysfunction is a feature of some neuropathies and not others. It has been suggested that some clinical and electrophysiologic attributes are predictable of autonomic impairment detected using laboratory testing; however, dear guidelines are unavailable. We evaluated 138 relatively unselected patients with peripheral neuropathy who underwent neurologic evaluation, electromyography (EMG), nerve conduction studies, and autonomic function tests to determine which variables were predictive of laboratory findings of autonomic failure. The variables evaluated were 1) clinical somatic neuropathic findings, 2) clinical autonomic symptoms, and 3) electrophysiologic findings. Autonomic symptoms were strongly predictive (Rs = 0.40, p < 0.001) of autonomic failure. Among the non-autonomic indices, absent ankle reflexes were mildly predictive (Rs = 0.19, p = 0.022) of autonomic impairment, but all others were not (duration, clinical pattern, severity, weakness, sensory loss). Electrophysiologic changes of an axonal neuropathy predicted autonomic impairment while demyelinating neuropathy did not. We conclude that autonomic studies will most likely be abnormal in patients who have symptoms of autonomic involvement and those who have an axonal neuropathy.

Autonomic Nervous System Diseases↗

PubMed1986

Adrenergic receptors in insensitive skin of spinal cord injured patients.

The factors responsible for the increased susceptibility to decubitus ulcers of the insensitive skin of spinal cord injury (SCI) patients are not known. Autonomic dysfunction leading to defective vascularity is a possibility. SCI removes cerebral control of the isolated nervous system which may mimic denervation hypersensitivity of autonomic neural synapses, where an increase in number and a scattering of the receptors on the postsynaptic membrane leads to abnormal responses. Since adrenergic receptors mediate vascular tone and regulate blood flow in the skin, it would be of great interest to determine whether the number and the concentration of receptors in the insensitive skin of SCI patients is modified as a function of time since injury. To achieve this aim, alpha and beta adrenergic receptors were measured in biopsies obtained from intact skin used to surgically repair decubitus ulcers in SCI patients admitted to The Institute for Rehabilitation and Research. Receptors were identified by competitive radioligand-binding assays in whole skin homogenates. Patients were divided into two groups: patients injured less than five years ("early") and patients injured more than five years ("late"). Alpha and beta adrenergic receptors in both cervical and thoracic SCI patients decreased in density in the "late" patients. The small sample size and the inherent large errors of the assay precluded achievement of statistically significant differences. Nevertheless, a definite trend is seen: Disconnection of the adrenergic neurons from brain integration may mimic denervation and lead to abnormal vascular responses in the insensitive skin.

Adult↗