Amidarone (AMD) is an antiarrhytmic drug with side effects on the nervous system. Cerebellum is seldom involved. We describe the case of a 56 years old male patient with a history of 4 month of cerebellar involvement characterized by gait unstadiness, ataxia, nistagmus and vertigo. He was on treatment with AMD because of ventricular arrythmia. The cerebellar syndrom progressively disappeared after drug whitdrawal and he was symptoms-free 4 months later. Similar symptoms appeared after another one month of automedication with the same drug. Structural lesions, metabolic, nutritional deficiencies or toxics were excluded. Mechanisms of cerebellar toxicity of AMD are yet unknown. The knowledge of the toxic effects of this drug, widely used in our country, would allow its early recognition.

La amiodarona (AMD) es una droga antiarritmica cuyos efectos adversos pueden comprometer el sistema nervioso central y periferico. La aparición de un síndrome cerebeloso es infrecuente. Se presenta un paciente masculino de 56 anos de edad que desarolla un síndrome pancerebeloso de 4 meses de evolución, que revierte luego de la suspension de la AMD. El cuadro reaparece meses mas tarde luego de un periodo de automedicacion con la droga. Los mecanismos tóxicos por los cuales la AMD afecta al cerebelo permanecen inciertos. Esta droga de amplia difusión en nuestro medio, como otros antiarritmicos, posee efectos sobre el sistema nervioso que deben ser tenidos en cuenta a fin de poder detectarlos precozmente.

Between 1974 and 1987 we have examined 50 patients with the diagnosis of myasthenia gravis. Female preponderance (2,5: 1) was found. Also, it was observed that most of the patients were aged between 20 and 49 years. Beside the clinical examination, the following tests were performed: (1) edrofonium test, (2) supramaximal repetitive nerve stimulation, (3) serum acetylcholine antibodies titers and (4) intraperitoneal passive transference of patient's sera to mice and recording of meepp's amplitude in the phrenic-diaphragm preparation in vitro. These four tests gave positive values for myasthenia in 90 to 100% of the cases. Thymus radiological examination was carried out by pneumomediastinography, which proved to correlate with the hsitological picture of the gland, and computed tomography, which disclosed some discrepances with the histology. Treatment was based on anticholinesterase drugs, corticosteroids and thymectomy, being the corticosteroids the most valuable therapeutical tool. Nine patients treated with steroids disclosed transitory worsening of their signs and symptoms at very early stages after onset of corticosteroid therapy, 6 of them had a disfavorable course in their follow-up. This observation seem to have value in the early prognosis of the disease.

Durante la observacion de 50 pacientes con Myasthenia gravis entre los anos 1974 y 1987 se encontro un predominio del sexo femenino en la proporcion de 2,5 a 1 y mayor frecuencia de presentacion en Ias 3ª y 5ª décadas de la vida. Luego de la evaluacion clínica, el diagnóstico fué confirmado mediante: (1) prueba dei edrofonio, (2) estímulo nervioso repetitivo, (3) dosaje de anticuerpos antirreceptor colinérgico y (4) transferencia pasiva del suero al raton con ulterior niedicion de la amplitud de mepp's. La positividad diagnostica vario entre el 90 y el 100%, segun el tipo de prueba empleada. El estúdio radiológico del timo fué hecho con neumomediastinografía. obteniendose excelente correlación con la descripcion histológica de la glândula, y con tomografia computada, que demostro menor eficiência diagnostica. El tratamiento fué implementado en base a anticolinesterásicos, timectomía y corticoterapia inmunosupresora, evidenciandose con esta última mejores resultados. Nueve pacientes desarrollaron peoria transitória del cuadro muscular al iniciarse el tratamiento esteroideo, 6 de ellos exhibieron posteriormente evolucion desfavorable. Esta observacion aparenta tener valor pronóstico en la evolucion de la MG.