RESUMEN

BACKGROUND: No studies have identified which patients with upper-extremity deep vein thrombosis (DVT) are at low risk for adverse events within the first week of therapy. METHODS: We used data from Registro Informatizado de la Enfermedad TromboEmbólica to explore in patients with upper-extremity DVT a prognostic score that correctly identified patients with lower limb DVT at low risk for pulmonary embolism, major bleeding, or death within the first week. RESULTS: As of December 2014, 1135 outpatients with upper-extremity DVT were recruited. Of these, 515 (45%) were treated at home. During the first week, three patients (0.26%) experienced pulmonary embolism, two (0.18%) had major bleeding, and four (0.35%) died. We assigned 1 point to patients with chronic heart failure, creatinine clearance levels 30-60 mL min(-1) , recent bleeding, abnormal platelet count, recent immobility, or cancer without metastases; 2 points to those with metastatic cancer; and 3 points to those with creatinine clearance levels < 30 mL min(-1) . Overall, 759 (67%) patients scored ≤ 1 point and were considered to be at low risk. The rate of the composite outcome within the first week was 0.26% (95% confidence interval [CI] 0.004-0.87) in patients at low risk and 1.86% (95% CI 0.81-3.68) in the remaining patients. C-statistics was 0.73 (95% CI 0.57-0.88). Net reclassification improvement was 22%, and integrated discrimination improvement was 0.0055. CONCLUSIONS: Using six easily available variables, we identified outpatients with upper-extremity DVT at low risk for adverse events within the first week. These data may help to safely treat more patients at home.

Asunto(s)

Técnicas de Apoyo para la Decisión , Pacientes Ambulatorios , Embolia Pulmonar/etiología , Trombosis Venosa Profunda de la Extremidad Superior/etiología , Adulto , Anciano , Anticoagulantes/efectos adversos , Canadá , Europa (Continente) , Femenino , Hemorragia/inducido químicamente , Humanos , Israel , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/mortalidad , Embolia Pulmonar/prevención & control , Sistema de Registros , Medición de Riesgo , Factores de Riesgo , América del Sur , Factores de Tiempo , Resultado del Tratamiento , Trombosis Venosa Profunda de la Extremidad Superior/diagnóstico , Trombosis Venosa Profunda de la Extremidad Superior/mortalidad , Trombosis Venosa Profunda de la Extremidad Superior/terapia

RESUMEN

Amyotrophic lateral sclerosis (ALS) is a progressive disorder resulting from degeneration of motor neurons in the brain and spinal cord. Sporadic ALS (SALS) accounts for the majority of patients and the familial form (FALS) represents fewer than 10% of all cases. Since it was found that there are Cu/Zn superoxide dismutase (SODI) gene mutations in 20% of FALS patients and that FALS and SALS patients show similar clinical features, it has been postulated that both may share a common physiopathological mechanism. We studied Cu/Zn SOD1 activity in cytosolic extracts of erythrocytes from 125 normal individuals and 40 SALS patients. We found that enzyme activity does not change with age in control subjects and tends to decrease in most SALS patients older than 60 years. A subpopulation of five SALS patients had significantly increased SOD1 activity; four of these patients over 70 years old. There was no correlation between enzyme activity and time of onset of the disease, or clinical forms of the illness. The variation in SOD1 activity in ageing SALS patients compared with younger patients suggests that they may undergo an oxidative disbalance contributing to the development of the disease.

Asunto(s)

Envejecimiento/metabolismo , Esclerosis Amiotrófica Lateral/enzimología , Superóxido Dismutasa/metabolismo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Eritrocitos/enzimología , Femenino , Humanos , Masculino , Persona de Mediana Edad

RESUMEN

Chronic demyelinating inflammatory polineuropathy (CIDP) is a disease which was recognized several years ago. However, the mechanism underlying its pathogenesis remains poorly understood. Nevertheless, there are some clues which strongly suggest that it constitutes an autoimmune disease. Since 1992 we have studied 30 cases. All them were clinically assessed and submitted to laboratory investigations encompassing nerve conduction studies, sera proteins immunoelectrophoresis, spinal fluid analysis and sural nerve biopsies. Upon clinical examination the usual findings were weakness, muscle atrophy, absence or diminished tendon jerks, paresthesias and hyposthesias. Electrophysiological studies disclosed marked slowing of the nerve conduction velocities, suggesting demyelination. Sera immunoelectrophoresis detected monoclonal gammopathy in 17% of the studied patients, which was not associated with lymphoproliferative illnesses. Of the patients 79% had increased levels of spinal fluid proteins. Seventeen patients gave their consent for performing a sural nerve biopsy; all the samples showed demyelination. In conclusion, we think that CDIP is a disease which can be recognized when the clinical assessment, the nerve conduction studies and the spinal fluid findings suggest the diagnosis. Although nerve biopsy may be strongly supporting, we believe that it has to be performed only if doubts arise from the clinical, electrophysiological or spinal fluid observations. It is worth noting that its early detection may benefit the patient through the administration of the right therapy precluding the eventual sequelae of the disease.

Asunto(s)

Enfermedades Desmielinizantes/patología , Polineuropatías/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biopsia , Enfermedad Crónica , Estudios Transversales , Enfermedades Desmielinizantes/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Conducción Nerviosa , Polineuropatías/fisiopatología , Estudios Retrospectivos

RESUMEN

Chronic demyelinating inflammatory polineuropathy (CIDP) is a disease which was recognized several years ago. However, the mechanism underlying its pathogenesis remains poorly understood. Nevertheless, there are some clues which strongly suggest that it constitutes an autoimmune disease. Since 1992 we have studied 30 cases. All them were clinically assessed and submitted to laboratory investigations encompassing nerve conduction studies, sera proteins immunoelectrophoresis, spinal fluid analysis and sural nerve biopsies. Upon clinical examination the usual findings were weakness, muscle atrophy, absence or diminished tendon jerks, paresthesias and hyposthesias. Electrophysiological studies disclosed marked slowing of the nerve conduction velocities, suggesting demyelination. Sera immunoelectrophoresis detected monoclonal gammopathy in 17

---

of the studied patients, which was not associated with lymphoproliferative illnesses. Of the patients 79

---

had increased levels of spinal fluid proteins. Seventeen patients gave their consent for performing a sural nerve biopsy; all the samples showed demyelination. In conclusion, we think that CDIP is a disease which can be recognized when the clinical assessment, the nerve conduction studies and the spinal fluid findings suggest the diagnosis. Although nerve biopsy may be strongly supporting, we believe that it has to be performed only if doubts arise from the clinical, electrophysiological or spinal fluid observations. It is worth noting that its early detection may benefit the patient through the administration of the right therapy precluding the eventual sequelae of the disease.

RESUMEN

We report 10 HTLV-I virus seropositive subjects, eight of them with HTLV-I associated myelopathy (HAM), two of them also infected with HIV as well as two asymptomatic HTLV-I+ relatives of two unrelated patients. HTLV-I is endemic in several tropical areas, where it causes different neurological diseases. Only few patients have been reported in our country since 1994. We studied 8 patients, who fulfilled the clinical criteria for chronic spastic paraplegia, and 2 other non-symptomatic HTLV-I seropositive relatives, with electromyography (EMG), motor and sensory conduction velocities (NCV), somatosensory, visual and brainstem auditory evoked potentials (SSEP, VEP and BAEP), Magnetic Resonance Images (MRI) and cerobrospinal fluid (CSF) analysis. The latter was carried out only in seven symptomatic patients. In every case positive ELISA tests for HTLV-I/II were confirmed by Western Blot. The two asymptomatic persons were clinically and electromyographically assessed, one of them was also submitted to SSEPs studies. Three patients were males. Patient's ages ranged from 5 to 65 years old. All symptomatic patients showed muscular weakness, spasticity with pyramidal signs and sphincter disturbances. Five of them had paresthesias and 2 had burning pain on their feet. The EMGs and the NCVs were normal in 7 patients and in the 2 asymptomatic ones. SSEPs, obtained by stimulating the posterior tibial nerves, were impaired in 7 patients and in the asymptomatic person who received the procedure. The 7 symptomatic patients who underwent lumbar puncture had positive tests for HTLV-I in CSF, 3 out of these 7 patients had also high protein levels and 4 had increased number of lymphocytes. In 2 patients intrathecal IgG production could also be demonstrated. MRI were normal in 7 patients and in the 2 asymptomatics, the exception being a female who had bilateral hyperintense lesions in cerebral white matter in T2. In conclusion, tropical spastic paraparesis is apparently a rare disorder in Argentina. However, some cases have been reported recently. Most probably, its prevalence is currently underestimated. Its diagnosis should be considered in every patient with progressive spastic paraplegia.

Asunto(s)

Potenciales Evocados , Paraparesia Espástica Tropical/fisiopatología , Adulto , Anciano , Argentina/epidemiología , Electromiografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Paraparesia Espástica Tropical/líquido cefalorraquídeo , Paraparesia Espástica Tropical/epidemiología

RESUMEN

Mitochondrial disorders are a group of diseases that can affect virtually all organ systems. A 19 year old man was seen in 1993 with neurologic abnormalities consisting of impaired function of muscles, diplopia, progressive loss of vision, impaired phonation and swallowing, during the last 10 years. Physical examination disclosed moderate wasting of the four limb muscles, mild motor weakness of neck muscles, symmetrical hyporeflexia, cerebellar dysfunction, severe external ophtalmoplegia and ptosis. Fundii oculi examination showed retinitis pigmentosa. The electromyogram demonstrated myopathic changes with normal nerve conduction velocities. The cerebrospinal fluid was normal, except for a mild increase in lactic acid. Histochemical study of a muscle biopsy specimen demonstrated ragged red fibers and increase of the subsarcolemal oxidative activity of mitochondriae. The diagnosis of Kearns-Sayre disease was confirmed and he was discharged advising physical therapy. On February 1995, he was again admitted, this time with right cardiac failure and worsening of all his previous symptoms and signs. He complained of myalgias and his muscle weakness was more striking on clinical examination. Echocardiography showed biventricular dilatation and left ventricular hypertrophy with preserved systolic function. A new muscle biopsy revealed an heteroplasmic deletion of 5 Kb with 80% of mutant mitochondrial DNA. In brief, we report a patient with the clinical phenotype of Kearns-Sayre syndrome who presented an acute congestive cardiac failure due to cardiomyopathy, an association which has seldom been, reported in the literature.

Asunto(s)

Insuficiencia Cardíaca/etiología , Síndrome de Kearns-Sayre/complicaciones , Adulto , Humanos , Síndrome de Kearns-Sayre/diagnóstico , Masculino , Índice de Severidad de la Enfermedad

RESUMEN

It has been recently recognized that increased titers of serum anti-GM1 antibodies may be associated with motoneurone diseases or with multiple motor neuropathy with or without conduction block and also with chronic sensorimotor neuropathy and Guillain-Barré syndrome. Santoro et al. were the first to note that anti-GM1 antibodies were able to bind to the nodes of Ranvier of the sural nerve of a patient with clinical signs and symptoms mostly resembling amyotrophic lateral sclerosis who also showed, in nerve conduction studies, multifocal motor nerve fibers conduction block and serum IGM anti-GM1 antibodies. The two patients presented in this report had asymetrical motor neurone disease with signs and symptoms of lower motoneurone involvement, and other signs, in the first patient, which suggested the existence of upper motoneurone damage. Besides, the second patient also had clinical sensory impairment in the lower limbs. Electrophysiologically, none of them had nerve conduction block but both showed inexcitable median and sural nerve sensory fibers. Both had high titers of anti-GM1. A sural biopsy of both patients showed immunoglobulins into the sensory fibers. However, we do not know whether the anti-GM1 antibodies bind to a cross-reactive glycolipid other than the GM1 itself. In any case, it seems that the presence of anti-GM1 antibodies might be a marker signalling a potentially treatable immune disorder which may have signs of lower and upper motor neurone disease and, also, clinical and electrophysiological evidences of peripheral sensory involvement.

Asunto(s)

Anticuerpos , Gangliósido G(M1)/inmunología , Enfermedad de la Neurona Motora/sangre , Enfermedad de la Neurona Motora/inmunología , Anciano , Humanos , Masculino , Persona de Mediana Edad

RESUMEN

Between 1974 and 1992, 118 patients with Myasthenia gravis (MG) were studied in our Hospital; 92 patients, followed up for longer than 6 months, were surveyed for therapeutical results. Patients were categorized according to Osserman criteria; 22 belonged to group I; 77 to group II; 4 to group III and 15 to group IV. MG predominated in females, the ratio was 1.87:1.0. This predominance was more obvious in patients below 35 years of age (2.68:1.0) than above (1.18:1.0). The greatest prevalence was found at the 3rd decade of life. The assessment of the diagnostic test is as follows: 1) edrophonium test was positive in 97% of 93 patients; 2) supramaximal repetitive stimulation performed in 3 different nerves yielded positive results in 83% of 118 patients. It is worth noting that the test was positive in 92% of patients with generalized MG while only 48% of those with ocular MG displayed positive results; 3) sera antiacetycholine receptor antibodies (ACRA) quantification produced positive results in 88% of the patients with generalized MG and in 33% of ocular MG. Altogether the positivity of this test was 83%; 4) passive transfer of patients sera (25 generalized and 2 ocular MG forms) to mice and measurement of mepp's amplitude in the phrenic-diaphragm in vitro preparation yielded positive results in 100% of the tested cases. Once the diagnosis was achieved, the characteristics of the thymus were studied combining pneumomediastinography and linear tomography (PT) in 60 patients. Thorax Computed tomography (CT) was performed in 51 patients. Of those patients who underwent thymectomy, the coherence between radiological and histological diagnosis for PT was 100% while for CT just 60%. More recently 14 patients were studied by combining both procedures. Reliability of this technique is currently under study. Therapeutical assessment was carried out adscribing patients to 5 different groups according to their response after treatment withdrawal; group 2: Improved, neither symptoms nor signs; group 1: Remission, neither symptoms nor signs while on medication or minimal disability without medication; group 3: Unchanged while on medication; group 4: Worse, patients with more severe or frequent signs and symptoms despite being on treatment, group 5: Death, patients who died due to respiratory failure. Groups 1 and 2 were considered successful while 3, 4 and 5 as unsuccessful. Treatment was based on the administration of anticholinesterase drugs (piridostigmine, neostigmine) in 113 patients. Of these, 35 received those drugs as the only medication of whom 39% obtained successful results. Steroids (methylprednisone) were administered to 75 patients, in 40 cases combined with anticholinesterase drugs.(ABSTRACT TRUNCATED AT 400 WORDS)

Asunto(s)

Miastenia Gravis , Adolescente , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Niño , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Miastenia Gravis/diagnóstico , Miastenia Gravis/tratamiento farmacológico , Miastenia Gravis/terapia , Estudios Retrospectivos , Distribución por Sexo

RESUMEN

We report a family with a disorder characterized by limbs and truncal undulating painful muscle spasms, short stature, fine and sparse hair in the scalp, absence of body hair, low implanted ears, big nose, pitched voice, enlarged heart ventricles and increased fasting glucose levels. Symptoms began in childhood and did not progress after the third decade of life. This disorder represents a new clinical phenotype among the several forms of dwarfism associated with neurological manifestations already described in the literature.

Asunto(s)

Enanismo/genética , Espasmo , Adulto , Humanos , Masculino , Contracción Muscular , Linaje , Fenotipo

RESUMEN

Between 1974 and 1992, 118 patients with Myasthenia gravis (MG) were studied in our Hospital; 92 patients, followed up for longer than 6 months, were surveyed for therapeutical results. Patients were categorized according to Osserman criteria; 22 belonged to group I; 77 to group II; 4 to group III and 15 to group IV. MG predominated in females, the ratio was 1.87:1.0. This predominance was more obvious in patients below 35 years of age (2.68:1.0) than above (1.18:1.0). The greatest prevalence was found at the 3rd decade of life. The assessment of the diagnostic test is as follows: 1) edrophonium test was positive in 97

---

of 93 patients; 2) supramaximal repetitive stimulation performed in 3 different nerves yielded positive results in 83

---

of 118 patients. It is worth noting that the test was positive in 92

---

of patients with generalized MG while only 48

---

of those with ocular MG displayed positive results; 3) sera antiacetycholine receptor antibodies (ACRA) quantification produced positive results in 88

---

of the patients with generalized MG and in 33

---

of ocular MG. Altogether the positivity of this test was 83

---

; 4) passive transfer of patients sera (25 generalized and 2 ocular MG forms) to mice and measurement of mepps amplitude in the phrenic-diaphragm in vitro preparation yielded positive results in 100

---

of the tested cases. Once the diagnosis was achieved, the characteristics of the thymus were studied combining pneumomediastinography and linear tomography (PT) in 60 patients. Thorax Computed tomography (CT) was performed in 51 patients. Of those patients who underwent thymectomy, the coherence between radiological and histological diagnosis for PT was 100

---

while for CT just 60

---

. More recently 14 patients were studied by combining both procedures. Reliability of this technique is currently under study. Therapeutical assessment was carried out adscribing patients to 5 different groups according to their response after treatment withdrawal; group 2: Improved, neither symptoms nor signs; group 1: Remission, neither symptoms nor signs while on medication or minimal disability without medication; group 3: Unchanged while on medication; group 4: Worse, patients with more severe or frequent signs and symptoms despite being on treatment, group 5: Death, patients who died due to respiratory failure. Groups 1 and 2 were considered successful while 3, 4 and 5 as unsuccessful. Treatment was based on the administration of anticholinesterase drugs (piridostigmine, neostigmine) in 113 patients. Of these, 35 received those drugs as the only medication of whom 39

---

obtained successful results. Steroids (methylprednisone) were administered to 75 patients, in 40 cases combined with anticholinesterase drugs.(ABSTRACT TRUNCATED AT 400 WORDS)

RESUMEN

We report a family with a disorder characterized by limbs and truncal undulating painful muscle spasms, short stature, fine and sparse hair in the scalp, absence of body hair, low implanted ears, big nose, pitched voice, enlarged heart ventricles and increased fasting glucose levels. Symptoms began in childhood and did not progress after the third decade of life. This disorder represents a new clinical phenotype among the several forms of dwarfism associated with neurological manifestations already described in the literature.

RESUMEN

C3H/HeN mice infected with the pantropic/reticulotropic Trypanosoma cruzi RA strain disclosed electromyographic signs (EMG) of neuropathic damage, while those infected with the myotropic CA-I strain showed EMG suggestive of primary muscle involvement. Although both strains induced inflammatory infiltrates in hamstring muscles (HM), damage was more severe in mice infected with CA-I. In sciatic nerves (SN) of mice infected with the RA strain, increased inflammatory changes, amastigote nests, and myelin digestion chambers were consistently found during the course of infection. On the other hand, the CA-I strain produced minor inflammatory changes without detectable amastigotes in such tissue. The RA strain induced chronic leptomeningitis in spinal cord (SC), while infiltrates were limited to spinal roots and dorsal ganglia in animals infected with CA-I. In mice infected with RA, phenotypic analysis of inflammatory lesions showed a consistent predominance of CD8+ T cells in nervous tissue throughout the course of infection and in HM during the chronic phase whereas natural killer cells were detected at 120 and 270 days pi. In mice infected with CA-I, a predominance of CD8+ cells in SN was only detected during the acute phase and in HM during the late chronic phase; B lymphocytes bearing surface IgM were present in all studied tissues at 270 days pi. In addition, positive fluorescence for mouse IgG was observed at 120 days pi in muscle interstitium. These results strongly suggest that T. cruzi strain-dependent mechanisms are involved in the development of neuromyopathic damage.

Asunto(s)

Enfermedad de Chagas/patología , Enfermedad de Chagas/fisiopatología , Animales , Antígenos de Protozoos/análisis , Linfocitos T CD8-positivos , Electromiografía , Ratones , Ratones Endogámicos C3H , Músculo Esquelético/parasitología , Unión Neuromuscular/parasitología , Unión Neuromuscular/patología , Nervio Ciático/parasitología , Médula Espinal/parasitología , Trypanosoma cruzi/inmunología

RESUMEN

UNLABELLED: We proposed to investigate subclinical cognitive impairment secondary to chronic Chagas' disease (CCD). No similar study was previously done. The neuropsychological performance of 45 chronic Chagasic patients and 26 matched controls (age, education place and years of residency in endemic area) was compared using the Mini Mental State Exam (MMSE), Weschler Memory Scale (WMS) and the Weschler Adult Intelligent Scale (WAIS). Non-parametric tests and Chi2 were used to compare group means and multivariate statistics in two way frequency tables for measures of independence and association of categorical variables with the disease. RESULTS: Chagasic patients showed lower MMSE scores (p < .004), poor orientation (p < .004), and attention (p < .007). Lower WMS MQ were associated with CCD (Chi2 5.9; p < .01; Fisher test p < .02). Lower WAIS IQ were associated with CCD (Chi2 6.3, p < .01; Fisher test p < .01) being the digit symbol (p < .03), picture completion (p < .03), picture arrangement (p < .01) and object assembly (p < .03) subtests the most affected. The impairment in non-verbal reasoning, speed of information processing, problem solving, learning and sequencing observed in chronic Chagas disease patients resembles the cognitive dysfunction associated with white matter disease.

Asunto(s)

Enfermedad de Chagas/complicaciones , Trastornos del Conocimiento/etiología , Adulto , Enfermedad de Chagas/psicología , Enfermedad Crónica , Escolaridad , Femenino , Lóbulo Frontal/fisiopatología , Humanos , Masculino , Análisis Multivariante , Escalas de Wechsler

RESUMEN

El objetivo de esta investigación fue determinar compromiso cognitivo en pacientes con enfermedad de Chagas en estadio cronico. Se estudio el perfil cognitivo de 45 pacientes chagasicos cronicos (CC) y 26 controles apareados por edad, educación, lugar y tiempo de residencia en area endemica. El Minimental State (MMSE), la escala de memoria de Weschlelr (WMS) y el test de Inteligencia de Weschler (WAIS) han dio utilizados para evaluar ambos grupos. Para el estudio estadistico de los datos se utilizaron pruebas no parametricas, Chi2 y estadistica multivariada en tabla de 2 x 2 para medir la association o independencia de variables categoriales con la presencia de enfermedad. Los resultados mostraron que los pacientes alcanzaban score menor que los controles en el MMSE (p < 0.004) debido basicamente a una mas pobre orientacion (P < 0.004) y atencion (p < 0.007). Cocientes bajos de memoria en el WMS se asociaron a la presencia de enfermedad (Chi25.9, p < 0.01; test de Fisher p < 0.02). Cocientes bajos de inteligencia en el WAIS se asociaron con la presencia de enfermedad (Chi26.3, p < 0.01; test de Fisher p < 0.01). Los subtests simbolos digitos (p < 0.03), completamientos de figuras (p < 0.03), ordenamiento de laminas (p < 0.01) y rompecabezas (p < 0.03) mostraron mayor compromiso. Estos resultados sugieren disfuncion del razonamiento no verbal, disminucion de la velocidad de procesado de la informacion y dificultad en la resolucion de problemas nuevos, en la habilidad de secuenciacion y en el aprendizaje. Este conjunto de hallazgos sugiere posible compromiso de la sustancia blanca subcortical en estos enfermos

Asunto(s)

Adulto , Humanos , Masculino , Femenino , Trastornos del Conocimiento/etiología , Enfermedad de Chagas/complicaciones , Enfermedad de Chagas/psicología , Escolaridad , Lóbulo Frontal/fisiopatología , Análisis Multivariante , Escalas de Wechsler

RESUMEN

The possible involvement of spinal alpha motor neurons, dorsal root ganglia and sensory fibers in human chronic Chagas' disease was previously demonstrated. More recently neuropsychological and sensory evoked potentials studies suggest the existence of central nervous system abnormalities in these patients. We assessed the state of central motor pathways in 46 patients with chronic Chagas' disease and 30 healthy volunteers by means of percutaneous cortical and spinal electrical stimulation. No significative slowness in pyramidal tracts (PT) conduction was found when comparing both groups. Neither any individual patient exhibited abnormally delayed PT conduction values beyond the upper normal limit of the healthy volunteers. These results suggest that, in contrast with other neural systems, the large myelinated PT fibers are usually spared in human chronic Chagas' disease.

Asunto(s)

Enfermedad de Chagas/fisiopatología , Potenciales Evocados Somatosensoriales/fisiología , Adolescente , Adulto , Enfermedad de Chagas/complicaciones , Enfermedad Crónica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Conducción Nerviosa/fisiología , Tiempo de Reacción

RESUMEN

The determination of the target for percutaneous thermocoagulation of the trigeminal rootlets has been generally based on the analysis of subjective clinical verbal and motor responses as assessed by freehand displacement of an electrode active at its straight or curved distal tip. In a previous report, we demonstrated that sensory and motor trigeminal evoked potentials are of practical value when attempting to localize the position of trigeminal electrodes. This report describes the technical features of a multiple electrode array designed to provide simultaneous access to various segments along a chosen trigeminal division or divisions, correlating at each segment clinical and electrophysiological data with radiological landmarks in the individual patient. The system consists of an outer needle with four windows at a distance of 15 mm from the tip. A multiple electrode array occludes the windows with four isolated caps for stimulation and recording. After correlating clinical verbal and motor responses with sensory and motor evoked potentials at each window and inter se, a target window is selected. A thermocouple fitted with a micromanipulator allows the accurate placement of the center of the active tip at the center of the chosen window. Preliminary data from 25 patients indicate that the technique provides a reliable sequential analysis of clinical, electrophysiological, and radiological data along the explored tract.

Asunto(s)

Potenciales Evocados , Microelectrodos , Nervio Trigémino/fisiopatología , Anciano , Femenino , Humanos , Trastornos del Movimiento/prevención & control , Parestesia/prevención & control , Complicaciones Posoperatorias/prevención & control , Radiocirugia/métodos , Nervio Trigémino/ultraestructura , Neuralgia del Trigémino/cirugía

RESUMEN

Estudios histológicos previos, realizados en el nervio ciático de ratone chagásicos crónicos, demostraron degeneración axonal y desmielinización. Con el fin de investigar los cambios funcionales en el nervio ciático y en músculos inervados por él, se estudiarón 14 ratones infectados, 12 meses antes de los experimentos, con tripomastigotes (clon K-98 de CA-I). Se exploró la actividad electromiográfica en los músculos isquiotibiales y la latencia y amplitud del potencial de nervio "in vivo". Como grupo control se emplearon 13 ratos de igual edad y peso. El electromiograma mostró que una parte de las unidades motoras funcionantes habían aumentado su amplitud, duración y número de fases de sus potenciales, señalando aumento del tamaño de sus territorios, hecho que sugiere reinervación muscular a partir del envío de colaterales axónicas hacia fibras musculares previamente denervadas. El potencial de acción del nervio ciático evidenció, en los animales infectados, disminución de su amplitud y prolongación de su latencia. Esta observación señala reducción del número de axones funcionantes en el nervio y desmielinización de las fibras remantes. Los hallazgos electrofisiológicos hechos en el nervio coinciden con las descripciones histológicas anteriores y proveen evidencia adicional del estado funcional de las fibras que lo integran en el modelo experimental de esta parasitosis (AU)

Asunto(s)

Animales , Ratones , Enfermedad de Chagas/complicaciones , Enfermedades del Sistema Nervioso Periférico/parasitología , Nervio Ciático/fisiopatología , Potenciales de Acción/fisiología , Electrofisiología , Electromiografía , Modelos Animales de Enfermedad , Ratones Endogámicos C3H

RESUMEN

Estudios histológicos previos, realizados en el nervio ciático de ratone chagásicos crónicos, demostraron degeneración axonal y desmielinización. Con el fin de investigar los cambios funcionales en el nervio ciático y en músculos inervados por él, se estudiarón 14 ratones infectados, 12 meses antes de los experimentos, con tripomastigotes (clon K-98 de CA-I). Se exploró la actividad electromiográfica en los músculos isquiotibiales y la latencia y amplitud del potencial de nervio "in vivo". Como grupo control se emplearon 13 ratos de igual edad y peso. El electromiograma mostró que una parte de las unidades motoras funcionantes habían aumentado su amplitud, duración y número de fases de sus potenciales, señalando aumento del tamaño de sus territorios, hecho que sugiere reinervación muscular a partir del envío de colaterales axónicas hacia fibras musculares previamente denervadas. El potencial de acción del nervio ciático evidenció, en los animales infectados, disminución de su amplitud y prolongación de su latencia. Esta observación señala reducción del número de axones funcionantes en el nervio y desmielinización de las fibras remantes. Los hallazgos electrofisiológicos hechos en el nervio coinciden con las descripciones histológicas anteriores y proveen evidencia adicional del estado funcional de las fibras que lo integran en el modelo experimental de esta parasitosis

Asunto(s)

Animales , Ratones , Enfermedad de Chagas/complicaciones , Nervio Ciático/fisiopatología , Enfermedades del Sistema Nervioso Periférico/parasitología , Modelos Animales de Enfermedad , Electromiografía , Electrofisiología , Potenciales de Acción/fisiología

RESUMEN

Early histological studies carried out in the sciatic nerve of mice chronically infected with Trypanosoma cruzi showed demyelination and scanty axonal degeneration. The experiments reported in this paper were designed to assess the functional state of the sciatic nerve and of some of the muscles it supplies. For these purposes 14 mice were infected with trypomastigotes (clon K-98, CA-I strain) 12 months before the investigation. Results were compared with 13 normal mice matched by age and weight. Hamstring muscles were studied electromyographically by means of a fine coaxial needle electrode and the sciatic nerve action potential characteristics were recorded with surface electrodes. All the experiments were carried out in vivo. In the infected mice the electromyogram showed that some motor unit potentials has enlarged amplitude and duration and increased number of phases, suggesting that the size of their territories had been enlarged, probably through axonal collateral sproutings and reinnervation of muscle fibers previously relinquished by their original innervation. The sciatic nerve action potential of the infected animals showed diminished amplitude and prolonged latency. These features signal reduced number of functional axons within the nerve and demyelination of the remaining conducting fibers. These findings are in line with the histological evidences of the involvement of the peripheral nervous system in Chagas disease and give additional information about the functional state of the peripheral nerves in the experimental model.

Asunto(s)

Enfermedad de Chagas/fisiopatología , Nervio Ciático/fisiopatología , Potenciales de Acción/fisiología , Animales , Modelos Animales de Enfermedad , Electromiografía , Electrofisiología , Ratones , Ratones Endogámicos C3H , Enfermedades del Sistema Nervioso Periférico/fisiopatología

Asunto(s)

Humanos , Masculino , Persona de Mediana Edad , Infecciones por HTLV-I/complicaciones , Paraparesia Espástica Tropical/diagnóstico , Paraparesia Espástica Tropical/etiología , Paraparesia Espástica Tropical/inmunología