[Evaluation of children with tuberculosis contact]. / Estudio del niñio en contacto con paciente tuberculoso.

Tuberculosis (TB) is a worldwide infectious disease, caused by Mycobacterium tuberculosis (Koch bacilli), that has re-emerged since the decade of the 80's in relation to the pandemic of HIV infection. Chile has one of the lowest TB prevalence rates in Latin America. In children, TB exhibits some differences from adult disease in terms of pathogenesis, clinical manifestations and probability of progression from the infected state to disease, making it more difficult to diagnose and increasing the likelihood of developing the disease once the infection is acquired. There is a National Program for the Prevention and Control of TB that allows us to develop prevention and chemoprophylaxis strategies. This article summarizes these strategies to guide the study and management of children in contact with TB patients.

Residue depletion of oxytetracycline (OTC) and 4-epi-oxytetracycline (4-epi-OTC) in broiler chicken's claws by liquid chromatography-tandem mass spectrometry (LC-MS/MS).

Antibiotics are widely used in poultry production for the treatment of bacterial diseases. However, residues may remain in products and by-products destined for human consumption or animal feeding. The claws of chickens, which are a by-product of the poultry industry, can directly or indirectly enter the food chain as meals destined to feed other productive animals. Thus, it becomes necessary to determine and quantify antimicrobial residues present in this matrix. The objective of the study was to assess the depletion of oxytetracycline (OTC) and its metabolite 4-epi-OTC in broiler chicken's claws. Claws of 32 broilers treated with a therapeutic dosage of 10% OTC during 7 days were analysed. Samples were taken at days 3, 9, 15 and 19 post-treatment. As for the control group, eight broiler chickens were raised under the same conditions. Extraction was carried out through EDTA-McIlvaine buffer, and clean-up employed a SPE C-18 Sep-Pak®. Instrumental analysis was performed through LC-MS/MS. The concentrations of both analytes were determined in claw samples until day 19 post-treatment. Average concentrations were within the LOD (20 µg kg-1) and LOQ (22 µg kg-1) for OTC and 84 µg kg-1 for 4-epi-OTC. Withdrawal times (WDTs) of 39 days for OTC and 54 days for 4-epi-OTC were established in claws based on 95% confidence. These findings demonstrate that claws can be a source of antimicrobial residue entry into the food chain, since the results showed that OTC and its metabolite can be found in chicken's claws for long periods, even exceeding the average lifespan of a broiler chicken.

Repeated tuberculin testing in patients with active pulmonary tuberculosis.

OBJECTIVE: The proportion of tuberculin reactors in a population and the intensity of tuberculin reactions have been shown to increase with increasing exposure to mycobacterial infection, eg, repeated BCG immunization. These observations suggested that tuberculin reactivity would become uniformly high in individuals with a high mycobacterial load who did not have a known cause of anergy. Since tuberculin reactivity has been measured to evaluate the possible genetic regulation of responses to mycobacteria in humans, it is important to study its behavior under conditions of ongoing, maximal exposure to mycobacteria. In the present study, we determined the mean size of tuberculin reactivity in BCG-immunized and unimmunized patients with pulmonary tuberculosis of recent onset, and the stability of tuberculin reactions during and after treatment of pulmonary tuberculosis. METHOD: Serial tuberculin testing was performed on patients with newly diagnosed active pulmonary tuberculosis diagnosed over a period of 2 years at the National Institute for Respiratory Diseases in Santiago, Chile. The first tuberculin test was performed at the time of diagnosis in 58 patients. Repeated tuberculin testing was performed 2 weeks later in 15 patients with initial reaction sizes < 15 mm. Four additional tuberculin tests were performed, one each at 3-months intervals in 42 patients regardless of the size of the initial tuberculin reaction. RESULTS: Tuberculin reactions at entry had a unimodal distribution in patients both with and without BCG scars (14.8 +/- 5.0 mm and 16.5 +/- 5.2 mm, respectively). A second tuberculin test in patients with initial reaction sizes < 15 mm showed a moderate, statistically significant increase in the mean reaction size (PPD1: 10.1 +/- 3.2 mm; PPD2: 11.9 +/- 4.8 mm). Repeated tuberculin testing over 1 year revealed no significant changes in reaction size. The mean reaction sizes were 15.8 +/- 5.0 mm at entry, 15.5 +/- 5.4 mm at 3 months, 17.2 +/- 5.2 mm at 6 months, 17.0 +/- 5.1 mm at 9 months, and 16.7 +/- 54 mm at 12 months. The standard deviation of a random observation within patients was 5.3 mm. The largest variations due to increased reactivity after 6 months of treatment were observed in patients with reaction < 15 mm at entry compared with hyperergic patients, and in BCG-immunized patients compared to unimmunized patients. CONCLUSIONS: In the presence of an ongoing mycobacterial infection, patients without anergizing conditions express a tuberculin reactivity that is relatively constant during and after treatment of pulmonary tuberculosis. The size and stability of the reactions seem to be determined by individual conditions that include the tuberculin reactivity at the time of diagnosis and the BCG immunization status.

Rate of infection and of reinfection by Echinococcus granulosus in rural dogs of the province of Rio Negro, Argentina.

Hydatidosis (cystic echinococcosis) constitutes a serious public health problem in the Province of Rio Negro, Argentina. In the present work it was intended to evaluate the prevalence of the canine echinococcosis in rural areas of the Province of Rio Negro and studied the reinfection rate in dogs after treatment with Praziquantel during the period 1980-1997. A total of 496 dogs were studied in 18 canine concentrations in order to establish the initial prevalence rate which was 42.3%. From 1980 onward dogs should have been systematically treated with anthelmintic every 2 months in rural areas and every 6 months in urban areas. We estimated that approximately 65% of dogs were treated. To determine the reinfection rate, 476 dogs (1984) and 598 dogs (1996) were studied after anthelmintic treatment during two sequential time periods (0-45; 46-90 days). In both cases treated animals were compared with untreated dogs. Prevalences were 3.5%, 6.7% and 21.3% in 1984 and 0.8%, 4.0% and 10.0% in 1996. For the purpose of surveillance a total number of 21,444 dogs were studied during 18 years. Prevalence of Echinococcus granulosus decreased significantly in the first year from 42.3% to 6.1%.

Ovine Echinococcus granulosus transmission dynamics in the province of Rio Negro, Argentina, 1980-1999.

In this work, the impact of a hydatidosis control programme for dogs on the intermediate ovine host was specifically analysed to determine the levels of prevalence achieved and the dynamics of parasite transmission, as well as to evaluate the quality of diagnostic systems in slaughterhouses. A field study was conducted in four slaughterhouses (Valcheta, Los Menucos, Jacobacci, Bariloche) that process animals coming from all the departments within the work area. The control programme for dogs entailed treating dogs with 5 mg/kg praziquantel at 2-month intervals for 20 years. Sample size was determined with a 10% error margin and a 95% significance level. Harvested viscera (liver, lungs, kidneys) were preserved in 5% formaldehyde and sent to the laboratory for diagnostic confirmation of both positive and negative specimens. The 61% initial prevalence dropped to 18.3% at the end of the 10-year period, observed differences proving significant (Chi-square=15.454, P=0.00). There were statistically significant increases in infection prevalence with age (Pearson's Chi-square=133.61, P=0.00). Overall, 37.2% of hydatidosis cases diagnosed in slaughterhouses were considered non-hydatid by histological study. On the other hand, 1.1% of those diagnosed as healthy were found to be infected with hydatidosis. The number of hydatid cysts per animal increased with age: 0.04 in lambs and 1.22 in adults (linear regression equation, -0.0539+0.0127 x age), whereas the average for the whole period was 3.7% in lambs and 20.5% in adults. Viability studies indicated that 63.8% of parasitised animals had viable cysts, out of which 53.3% were fertile. Diagnosis of infection in sheep made by means of an adjusted statistical design and with histological confirmation of the presumptive diagnosis made in slaughterhouses demonstrated the flaws of the official systems for epidemic surveillance of hydatidosis. However, there was no overall significant difference in slaughterhouse and laboratory data.Ro was 0.53 and could imply a decrease in reproductive capacity of the parasite and steady state extinction.

Rash y anemia aplásica inducidos por fenitoína: caso clínico / Phenytoin-induced rash and aplastic anemia: case report

Rash is a common side effect associated with antiepileptic drugs. The rate of a phenytoin rash is 5.9 percent and increases to 25 percent in those with another antiepileptic drug rash. Aplastic anemia is an adquired hematopoietic stem-cell disorder characterized by pancytopenia of the peripheral blood and hypocellular bone marrow. The use of phenytoin is associated with a 3.5 fold increased risk of aplastic anemia. We report a case of a 70-year-old woman who developed two severe adverse reactions simultaneously with phenytoin: a maculopapular pruritic rash with involvement of mucous and an aplastic anemia. Both conditions normalized after phenytoin withdrawal.

El rash es un efecto secundario común asociado al uso de fármacos antiepilépticos. La frecuencia de rash con fenitoína se ha estimado en un 5,9 por ciento y asciende a un 25 por ciento en pacientes que han presentado rash con otro fármaco antiepiléptico. La anemia aplásica es una anomalía adquirida de las células madre hematopoyéticas caracterizada por pancitopenia de la sangre periférica y médula ósea hipocelular. Los pacientes tratados con fenitoína presentan un riesgo 3,5 veces mayor de desarrollar anemia aplásica. Presentamos el caso de una mujer de 70 años que desarrolló dos reacciones adversas severas y simultáneas a la fenitoína: un exantema maculopapular pruriginoso con compromiso de mucosas y una anemia aplásica. Ambas condiciones se resolvieron completamente con la suspensión del fármaco.

Estudio del niño en contacto con paciente tuberculoso / Evaluation of children with tuberculosis contact

La tuberculosis (TBC) es una enfermedad de distribución mundial, producida por Mycobacterium tuberculosis (bacilo de Koch), que ha re-emergido desde la década de los 80 en relación a la pandemia de VIH. Chile es uno de los países latinoamericanos con menores tasas de prevalencia de TBC. En los niños, la TBC presenta algunas características distintas al adulto en cuanto a patogenia, clínica y probabilidad de progresión desde una infección latente a enfermedad, siendo más difícil realizar el diagnóstico y mayor la probabilidad de desarrollar enfermedad una vez infectados. Existe un Programa Nacional de Prevención y Control de la TBC que nos permite plantear estrategias de prevención y quimioprofilaxis. Este artículo esquematiza estas estrategias para orientar el estudio y manejo de niños que entran en contacto con pacientes con TBC.

Tuberculosis (TB) is a worldwide infectious disease, caused by Mycobacterium tuberculosis (Koch bacilli), that has re-emerged since the decade of the 80’s in relation to the pandemic of HIV infection. Chile has one of the lowest TB prevalence rates in Latin America. In children, TB exhibits some differences from adult disease in terms of pathogenesis, clinical manifestations and probability of progression from the infected state to disease, making it more difficult to diagnose and increasing the likelihood of developing the disease once the infection is acquired. There is a National Program for the Prevention and Control of TB that allows us to develop prevention and chemoprophylaxis strategies. This article summarizes these strategies to guide the study and management of children in contact with TB patients.

Manejo del accidente cerebro-vascular isquémico agudo / Acute ischemic stroke therapy

El infarto cerebral es una patología con gran impacto en la salud pública de nuestro país. Al ocluirse el flujo sanguíneo de una arteria cerebral se produce una cascada de eventos moleculares que llevan al daño neuronal. En esta condición, queda un tejido con circulación limítrofe alrededor del infarto, la llamada penumbra isquémica, que es potencialmente recuperable, sólo si se produce rápidamente la reperfusión. La recanalización precoz del vaso ocluído es la terapia más efectiva en el infarto cerebral agudo. En la última década ha habido importantes avances en el manejo de esta patología. Estudios de gran escala han mostrado el beneficio de la trombolisis intravenosa administrada en las primeras tres horas del inicio de los síntomas, el beneficio de la trombolisis intraarterial en las primeras seis horas, el uso de antiplaquetarios en las 48 horas iniciales y la importancia del adecuado manejo de las condiciones médicas asociadas, en unidades especializadas (“stroke unit”), para mejorar el desenlace. Las estrategias actuales se orientan a expandir la ventana terapéutica por sobre las tres horas clásicas y evaluar maniobras que tengan más beneficios en los pacientes de mayor gravedad. El propósito de este artículo es revisar, algunas de estas terapias que parecen más promisorias.

Stroke has a major impact on the public health of our nation. When focal occlusions disrupt blood flow to the brain, a cascade of molecular events ensues that produces cell injury. Tissues with borderline cerebral blood flow comprise the ischemic penumbra, areas of stunned parenchyma surrounding the ischemic core, which have potential for recovery, but only if reperfusion is rapidly established. Early re-canalization of an occluded artery is the most effective treatment for this condition. Over the last decade there have been rapid advances in the management of patients with acute ischemic stroke. Large-scale trials have demonstrated beneficial effects of intravenous thrombolytic treatment delivered within 3 hours of symptom onset, intra-arterial thrombolytic therapy within 6 hour of symptom onset, antiplatelet therapy within 48 hours of symptom onset and other studies have suggested that the supportive medical measures undertaken in Stroke Units also improve patient outcomes. Novel therapeutic strategies are seeking to expand the therapeutic time window to > 3 hours and to more effectively treat patients with a severe infarction. The purpose of this article is to review some of the current therapies for acute ischemic stroke.

Utilidad diagnóstica de un cuestionario de sueño y de la escala de somnolencia de Epworth en el síndrome de apneas/hipopneas obstructivas del sueño (SAHOS) / The usefulness of a sleep questionnaire and the epworth sleep scale in the diagnosis of obstructive sleep apnea syndrome (OSAS)

Introduction: Obstructive sleep apnea syndrome (OSAS) is a common disease associated with significant morbidity, including excessive daytime sleepiness, cardiovascular disease and stroke. Method: We studied prospectively the patients sent to our sleep laboratory for polysomnography (PSG) during 6 months. One-hundred patients were interviewed with a sleep questionnaire, 3 of them were ruled out because the lacking of PSG and 2 who no completed the Epworth sleep scale (ESS). Results: Out of the 95 patients, there were 85 men and 10 women, with a mean age of 47.4 +/- 12.5 years, obesity was found in 42.5 percent, an ESS greater than 11 points was found in 56.8 percent, loud snoring in 93.7 percent, breathing cessation in 68.4 percent, excessive daytime somnolence in 57.9 percent. PSG revealed no OSAS in 14.7 percent, slight OSAS in 27.4 percent, moderate OSAS in 21 percent y severe OSAS in 36.8 percent. Body mass index and breathing cessation reported by the couple had the highest discriminative power with a sensibility of 87 percent and specificity of 50 percent for ruled out severe OSAS. Conclusion: A severe OSAS is less probable when there is absence of breathing cessation during sleep reported by the couple and an IMC <30 Kg/m².

Introducción: El SAHOS presenta una alta prevalencia en estudios internacionales, con importantes repercusiones en los sistemas cardio, cerebrovascular y en la calidad de vida de las personas. Método: Estudiamos prospectivamente a los pacientes enviados para Polisomnografia (PSG) a nuestro laboratorio de sueño, en un período de 6 meses. Previo consentimiento informado, se les aplicó la Escala de Somnolencia de Epworth (EE) y un Cuestionario de Sueño. Fueron entrevistados 100 pacientes, excluyéndose 3 por no haberse realizado PSG y 2 que no completaron la EE. Resultados: Se analizaron 95 pacientes, 89,5 por ciento hombres, edad promedio 47,4 +/- 12,5 años, obesidad en 49,5 por ciento, EE mayor de 11 en 56,8 por ciento, ronquido en 93,7 por ciento, pausas respiratorias en 68,4 por ciento, somnolencia diurna excesiva en 57,9 por ciento, cansancio al despertar en 86,3 por ciento. La PSG no demostró SAHOS en 14,7 por ciento, hubo 27,4 por ciento con SAHOS leve, 21 por ciento> moderado y 36,8 por ciento> severo. Las variables presencia de pausas respiratorias observadas por la pareja e índice de masa corporal (IMC) predicen la ausencia de SAHOS severo, con una sensibilidad de 87 por ciento y especificidad de 50 por ciento. Conclusión: En la evaluación de pacientes con sospecha de SAHOS, la no observación de pausas respiratorias durante el sueño por parte de la pareja y el IMC menor de 30 Kg/m² hacen menos probable que exista un SAHOS severo.

Aplicación de un cuestionario de sueño y la escala de somnolencia de Epworth en un centro de salud familiar / Application of a sleep questionnaire and the Epworth sleepiness scale in a family health center

Introduction: Sleep disorders, especially sleep breathing disorders, have not been well studied in the patients attending a family health center in Chile. Sleep breathing disorders have been linked to cardiovascular and cerebrovascular diseases, which are important causes of morbidity and mortality. Method: We studied a randomized sample of 180 adult patients (135 women and 45 men, with a mean age of 45.6 years) consulting a public family health center with the Epworth Sleepiness Scale and a Sleep Questionnaire which include assessment of obesity medical conditions, medications and smoking habit, blood pressure, sleep habits, snoring, breathing cessation, insomnia, daytime sleepiness and depressive symptomatology Results: Hypertension was found in 37.2 percent, diabetes in 11.1 percent, dislipidemia in 19.4 percent, smoking in 34.4 percent. Body mass index > of30 Kg/m2 was found in 38.3 percent). Twenty five patients (13.9 percent>) had an Epworth score >ofl5. Loud snoring was reported in 56.7 percent>. Breathing cessation was reported by the spouses in 21.7 percent>. Difficulty for sleep initiation was present in 21.7 percent and to maintain sleep in 21.7 percent. Daytime sleepiness was present in 29.4 percent. Twelve patients (6.7 percent) had the highest score in a visual analog scale for daytime somnolence. An affirmative answer for persistent sadness or low mood and loss of interest or pleasure in the last month was reported by 43.8 percent of the patients. Conclusion: It is noteworthy the high frequency of undiagnosed sleep disorders found in a population consulting by others pathologies. These results would be useful for the planning of public health programs which should include sleep disorders.

Introducción: Los trastornos del sueño, especialmente el Síndrome de Apneas del Sueño (SAS), presentan una alta prevalencia internacional, pero no existen estudios en Chile. Método: Durante un período de 6 meses, se ingresó progresivamente una muestra randomizada de 180 pacientes mayores de 18 años (135 mujeres, 45 hombres) que consultaron en un Centro de Salud Familiar, para evaluar la frecuencia de trastornos de sueño con la Escala de Somnolencia de Epworth y un Cuestionario de Sueño especialmente diseñado que incluyó: estado nutricional, enfermedades médicas, uso de medicamentos, tabaco y alcohol, hábitos de sueño, ronquido, pausas respiratorias, insomnio, somnolencia diurna excesiva y síntomas depresivos. Resultados: Se encontró hipertensión arterial en 37,2 por ciento, diabetes en 11,1 por ciento, dislipidemia en 19,4 por ciento y tabaquismo en 34,4 por ciento, IMC > de 30 kg/m2 en 38,3 por ciento, Epworth > 15 en 13,9 por ciento, ronquido en 56,7 por ciento, pausas respiratorias en 21,7 por ciento, somnolencia diurna excesiva en 29,4 por ciento, dificultad en la iniciación (21,7 por ciento) y mantención del sueño (21,7 por ciento). Tristeza persistente y/o pérdida de interés en sus actividades o falta de disfrute en el último mes fue referida por 43,8 por ciento de los pacientes. Conclusión: La alta frecuencia de trastornos del sueño encontrados, hacen necesario incluirlos en la planificación de programas de salud en nuestro país, para su adecuado diagnóstico y tratamiento, especialmente considerando el que algunos de estos trastornos constituyen factores de riesgo para enfermedades vasculares cardíacas y cerebrales.

Síndrome de piernas inquietas: estudi clínico en población general adulta y en pacientes urémicos / Restless legs syndrome: a clinical study in chilean general population and in uremic patients

Background: The restless legs syndrome (RLS) is a movement disorder characterized by an imperative urge to move the legs, associated with paraesthesias, motor restlessness and worsening of symptoms at night with at least partial relief by activity. Its prevalence ranges between 2-15 percent of general adult population and 20-30 percent of uremic patients. Aim: To evaluate the frecuency and the clinical features of RLS in a sample of general adult population and in uremic patients, in Chile, correlating it with biochemical parameters. Method: 100 relatives of outpatients and 166 uremic patients undergoing chronic haemodialysis were interviewed assessing the presence and severity of RLS according to current diagnostic criteria. Biochemical parameters assessed were hematocrit, serum ferritin, phosphate, intact parathyroid hormone (iPTH) levels. Results: 13 percent of the general population sample was affected, 15 percent of them were severe. Forty three cases were found among uremic patients (25.9 percent) (p <0.01 vs general population), 60 percent of them were severe and women were affected with higher frequency (p <0.05) and severity (p <0.01). Four patients presented RLS even during hemodialysis. No correlation was found with biochemical parameters. Most RLS cases had not been diagnosed previously. Conclusions: In our population RLS is common and undetected. It is especially prevalent and severe in uremic patients: we found no evidence that anaemia, iron deficiency or iPTH level play a major pathogenic role. Our findings emphasize the need of greater medical awareness of RLS because available therapy may improve the quality of life

Activador del plasminógeno tisular intravenoso en el tratamiento del infarto cerebral agudo: factibilidad, seguridad y eficacia en los primeros dos años de práctica clínica / Intravenous tissue plasminogen activator in acute ischemic stroke: feasibility, safety and efficacy in the first 2 years of clinic practice

Background: The only effective therapy for the treatment of acute ischemic stroke is the infusion of tissue plasminogen activator in the first three hours after the onset of symptoms. Aim: To report the experience with tissue plasminogen activator infusion in the treatment of acute ischemic stroke. Patients and methods: Ten males and 10 females, aged 52 to 85 years old with an acute ischemic stroke, admitted within 89 min after the onset of symptoms were studied. Tissue plasminogen activator was infused following the guidelines designed by the National Institute of Neurological Disorders and Stroke (NINDS). Patients were assessed according to Rankin scale after three months of follow up. Results: All patients had normal CAT scans. The delay between the onset of symptoms and the infusion ranged from 75 to 180 min. One patient had a gastrointestinal bleeding due to a gastric ulcer and one patient had a fatal intracranial hemorrhage. After three months of follow up, 38 percent of patients had a good recuperation (Rankin 0 to 1), 33 percent had a mild to moderate disability (Rankin 2 or 3) and 14 percent had a moderate to severe disability (Rankin 4). There was a 15 percent mortality. Conclusions: This series show that treatment of acute ischemic stroke with tissue plasminogen activator is feasible and safe. The obtained results are similar to those reported abroad

Perfil clínico y de laboratorio de la encefalomieloneuropatía asociada a HTLV-1 en Chile / Clinical and laboratory aspects of encephalomyeloneuropathy associated with HTLV-I in Chile

En Chile el 44,2% de los pacientes con paraparesis espástica progresiva son HTLV-I positivos en los estudios de ELISA y Western-blot. Esta patología predomina en mujeres (3,6 mujeres a 1 hombre), con un promedio de edad de 45,8 años. Clínicamente se manifiesta por una paraparesis espástica lentamente progresiva, con compromiso del esfínter vesical, habitualmente sin alteraciones de la sensibilidad, pero que puede asociarse a parestesias distales. Se observa leve pleocitosis en el LCR (34%), aumento del índice IgG (88,2%) y alteración de los potenciales evocados somatosensoriales (90%). En el estudio anátomo-patológico se encuentra un compromiso del tracto cortico-espinal con pérdida de axones y mielina y la presencia de manguitos mononucleares alrededor de los vasos. Se ha definido el perfil clínico, de laboratorio, electrofisiológico y neuropatológico de esta enfermedad en Chile

Estudio de la prosodia en lesiones del hemisferio derecho / Prosody in right hemisphere lesions

El término prosodia se refiere al significado emocional y semántico del habla debido a variaciones en el tono, acento o ritmo. Se han distinguido diversos subtipos de prosodia postulándose que el hemisferio derecho regularía su producción. Para investigar la capacidad de prosodia en 21 pacientes con lesiones únicas de hemisferio derecho y comparar con 16 sujetos controles sin lesión cerebral, adaptamos a nuestro idioma una prueba descrita en inglés realizándose 3 experimentos. En el primero los sujetos deberían diferenciar palabras similares que variaban en el acento o tono llevando a diferente significado. De una lámina debían seleccionar un dibujo que representara el significado de la palabra dicha. En el segundo experimento se les hacía oir una grabación con 25 pares de frases idénticas; en 15 pares una frase difería de la otra en la acentuación de diferentes palabras, variando de esta manera el significado. Como control se entremezclaban 10 pares de frases exactamente con la misma entonación. El sujeto debía decir si eran frases con entonación similar o diferente. En el tercer experimento el sujeto debía repetir una frase dada con la misma entonación, presentándose 20 de tales frases. A diferencia de los resultados presentados en sujetos de habla inglesa, ninguna diferencia estadísticamente significativa encontramos entre pacientes con lesiones de hemisferio derecho y controles, aunque hubo tendencia de estos últimos a rendimientos mejores. En la literatura anglosajona diferencias significativas fueron encontradas con series más pequeñas que la nuestra. Sorprendentemente, nuestros sujetos controles rindieron peor que sus homólogos norteamericanos, lo que explicamos por la vía de lo cultural, tenga ésto un sustrato orgánico o no. También sorprendió un rendimiento muy alto en una prueba de comprensión de prosodia por parte del grupo lesionado y pensamos que inadvertidamente este grupo contenía una preparación alta de portadores de lesiones anteriores del hemisferio derecho, lo que facilitaría la comprensión prosódica pero no la expresión

Disección de arteria vertebral: presentación de un caso y revisión de la literatura / Vertebral artery disection: 1 case report and literature review

Vertebral artery dissection seems to be a frequent cause of stroke in young adults. We report a 34 years old female that suffered a cardiac arrest while practicing aerobics, with complete recovery and four months later developed an acute Wallenberg`s syndrome. Magnetic resonance imaging showed an infarction in the right cerebellar hemisphere. Angiography revealed an occlusion of the third segment (V3) of the right vertebral artery which was hypoplastic. The patient was anticoagulated with a favorable clinical outcome. A follow up angiography, performed six months later, showed an incomplete recanalization of the vessel. Vertebral artery dissection should be suspected in every patient with ischemic symptoms or signs related to the vertebrobacilar territory, specially in young or middle aged patients with a history of trauma. magnetic resonance imaging and ultrasound-doppler examinations are the diagnostic test of choice

Potenciales evocados somatosensoriales y respuesta sintomática a medicamentos dopaminérgicos en enfermedad de Parkinson / Somatosensory evoked potentials and sintomatic response to dopaminergic drugs in Parkinson's disease

Short latency somatosensory evoked potentials were measured in 10 patients with Parkinson's disease before and after tha administration of Apomorphine 5 mg sc. Eight of these subjects were reassessed after one month of treatment with Levo-dopa. These potentials were measured in other nine subjects before and after one month of treatment with Selegiline 10 mg od. There was a significant increase of frontal potential N30 in nine of 10 subjects that received apomorphine, in seven of 8 patients treated with Levodopa and 7 of 9 patients treated with Selegiline. No changes in N20 parietal potential were observed. During apomorphine test, changes in N30 potential preceded clinical improvement in 6 patients and occurred simultaneously in 3 patients. No changes with apomorphine in N30 potential were observed in 2 healthy males. There was no relationship between electrophysiological changes and duration of disease or motor fluctuations. It is concluded that short latency somatosensory evoked potentials are an objective means of measuring dopaminergic response in patients with Parkinson's disease