RESUMEN
We present two patients with epilepsy who experienced disabling myoclonic jerks during lamotrigine treatment. Both were young males who had intractable cryptogenic generalized epilepsy since childhood. They received a lamotrigine-valproate combination resulting in an excellent improvement; however, after 2-3 years of therapy, both patients were hospitalized because of continuous disabling myoclonic jerks. The dosage of lamotrigine was the same before and at the onset of myoclonus. When the severe myoclonus started, both patients had a higher serum lamotrigine level (16.5 and 17.7 mg/L, respectively) than in previous findings. Disabling myoclonus was also present during lamotrigine monotherapy with 15 mg/L serum level. Lamotrigine may severely worsen myoclonic phenomena in generalized epilepsies, in which adverse events may be dependent on drug serum level.
Asunto(s)
Anticonvulsivantes/efectos adversos , Epilepsias Mioclónicas/inducido químicamente , Triazinas/efectos adversos , Adolescente , Adulto , Anticonvulsivantes/sangre , Electroencefalografía , Electromiografía , Epilepsias Mioclónicas/fisiopatología , Epilepsia Generalizada/complicaciones , Epilepsia Generalizada/tratamiento farmacológico , Epilepsia Generalizada/fisiopatología , Humanos , Lamotrigina , Masculino , Triazinas/sangreRESUMEN
Physiological properties of single units were investigated in the suprageniculate nucleus (SG) and in the cerebral cortex along the anterior ectosylvian sulcus (AES), including the insular cortex. The recording was performed with the aid of carbon-filled glass micropipetts in barbiturate-anesthetized cats. The main findings of the study can be summarized as follows. 1. The physiological properties of the cells in the suprageniculate nucleus and in the AES/insular cortex exhibited striking similarities in a series of aspects: (a) The frequencies of occurrence of uni-, bi- and trimodal cells were similar. (b) The majority of the unimodal cells (75% in the AES/insular region and 65% in the SG) has visual sensitivity in both structures. The bimodal and trimodal cells were also dominated by visual sensitivity. (c) The somatosensory and auditory modalities were similarly present in both structures, although less frequently than the visual one. (d) No systematic topological organization was found in either structure. (e) The visual, somatosensory and auditory receptive fields were uniform and covered a fairly large proportion of the personal space. 2. Statistical comparison of some physiological properties of cells situated deep in the AES with those of cells in the insular cortex revealed differences as follows: (a) The insular cortex contained significantly more bi- and trimodal cells than the sulcal areas. (b) Cells in the insular cortex preferred significantly lower stimulus velocities and larger stimuli than cells in the depths of the AES. These results seem to support the notion of a suprageniculate-AES/insular thalamo-cortical multisensory entity. Additionally, the physiological differences between the sulcal AES cortex and gyral insula are in agreement with the morphological differences found earlier in the afferentation of these areas (Norita et al., 1986, 1991).
Asunto(s)
Mapeo Encefálico , Corteza Cerebral/fisiología , Potenciales Evocados Auditivos/fisiología , Potenciales Evocados Somatosensoriales/fisiología , Potenciales Evocados Visuales/fisiología , Cuerpos Geniculados/fisiología , Animales , Gatos , Vías Nerviosas/fisiologíaRESUMEN
For assessment of clinical and prognostic values of cardiac autonomic neuropathy, 53 patients with diabetes mellitus were followed-up for five years. Parasympathetic innervation was assessed by recording heart rate variability during deep breathing, Valsalva manoeuvre and lying-to-standing while sympathetic function was evaluated by measuring postural change in systolic blood pressure. During the follow-up period 1 of 23 diabetic patients died in group without signs of cardiac autonomic neuropathy whereas 2 of 13 diabetics and 10 of 17 diabetics deceased in groups with mild and definitive signs of cardiac autonomic neuropathy, respectively. At reinvestigation, the values of tests for parasympathetic impairment worsened or did not change significantly while improvement in these tests was only exceptionally observed in 40 diabetic patients. No significant change in values of test for sympathetic function was documented during the follow-up period suggesting that parasympathetic (vagal) impairment might precede the sympathetic dysfunction during development of autonomic neuropathy in diabetic patients. No correlation was observed between changes in cardiac autonomic neuropathy and alterations in distal somatic neuropathy (assessed by measurement of motor nerve conduction velocity in peroneal nerves) during the prospective study. Definitive cardiac autonomic neuropathy--as one of the late complications of diabetes mellitus--suggests poor prognosis in diabetic patients.
Asunto(s)
Enfermedades del Sistema Nervioso Autónomo/diagnóstico , Angiopatías Diabéticas/diagnóstico , Neuropatías Diabéticas/diagnóstico , Cardiopatías/diagnóstico , Adulto , Anciano , Enfermedades del Sistema Nervioso Autónomo/etiología , Angiopatías Diabéticas/complicaciones , Neuropatías Diabéticas/complicaciones , Femenino , Estudios de Seguimiento , Cardiopatías/etiología , Humanos , Masculino , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
Signs of autonomic cardiac neuropathy and its association with distal somatic neuropathy were investigated in 36 type 1 and 28 type 2 diabetic patients free from clinical symptoms of autonomic neuropathy. Using bedside tests (deep-breathing, Valsalva manoeuvre and lying-to-standing) definitive cardiac autonomic neuropathy was found in 28 patients (44%), early cardiac autonomic neuropathy was observed in 19 patients (30%) while 17 patients (26%) showed no alterations. The values of motor nerve conduction velocity in peroneal nerves (41.8 +/- 0.7 m/s, mean +/- SEM) were significantly (p less than 0.01) lower in patients with definitive cardiac autonomic neuropathy than those (45.8 +/- 1.1 m/s) of patients without any signs of cardiac autonomic neuropathy. These latter values were, however, significantly (p less than 0.001) lower than those (53.7 +/- 0.7 m/s) of control subjects (n = 50). Signs of early or definitive cardiac autonomic neuropathy were recorded in 31 of 35 diabetic patients with distal somatic neuropathy assessed by measurement of motor nerve conduction velocity in peroneal nerves. It was concluded that abnormal results of noninvasive tests for autonomic neuropathy, i.e. alterations in cardiorespiratory reflexes indicating parasympathetic impairment of cardiac innervation could be often found in diabetic patients without clinical signs of autonomic neuropathy. These alterations could be frequently observed in diabetic patients with distal symmetrical somatic neuropathy.
Asunto(s)
Enfermedades del Sistema Nervioso Autónomo/complicaciones , Neuropatías Diabéticas/complicaciones , Reflejo Anormal , Adulto , Anciano , Creatinina/sangre , Creatinina/metabolismo , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Persona de Mediana Edad , Conducción Nerviosa/fisiología , Nervio Peroneo/fisiopatología , Respiración/fisiología , Maniobra de Valsalva/fisiologíaRESUMEN
Signs of autonomic cardiac neuropathy and its association with distal symmetrical polyneuropathy were investigated in adult diabetic patients free from clinical symptoms of autonomic neuropathy. Cardiorespiratory reflexes were assessed by non-invasive tests (deep-breathing, Valsalva manoeuvre and lying-to-standing) evaluating parasympathetic function of cardiac innervation. Measurement of motor nerve conduction velocity in both peroneal nerves and neurological physical examination were carried out for assessment of distal somatic neuropathy. Among 64 diabetics, definitive signs of cardiac autonomic neuropathy were found in 28 patients (44%), early signs of cardiac autonomic neuropathy were observed in 19 patients (30%) while no alterations were documented in 17 patients (26%). The values of motor nerve conduction velocity in peroneal nerves (41.8 +/- 0.7 m/s) were significantly (p less than 0.01) lower in patients with definitive cardiac autonomic neuropathy (n = 28) than those (45.8 +/- 1.1 m/s) of patients without any signs of cardiac autonomic neuropathy (n = 17). These latter values were, however, significantly (p less than 0.001) lower than those (53.7 +/- 0.7 m/s) of control subjects (n = 50). Abnormal results of non-invasive tests for autonomic neuropathy, i.e. alterations of cardiorespiratory reflexes indicating parasympathetic impairment in cardiac innervation could be often found in diabetics without clinical signs of autonomic neuropathy. These alterations could be frequently observed in diabetics with distal symmetrical neuropathy as well as in diabetic patients with one or more late specific complications.