Identificación clínica y patológica de las diversas formas de la enfermedad de Creutzfeldt Jakob en Chile / Clinical and pathologic identification of different forms of Creutzfeldt Jakob disease in Chile

Background: The identification of clinical and pathological forms of Creutzfeldt Jakob Disease (CJD) started with the first cases of the disease. Genetic and biomolecular prion status assessment are allowing now a better classification. Aim: To identify the clinical forms of the disease that exist in Chile, based on clinical and neuropathological data. Patients and Methods: Review of records of 40 patients with CJD in whom a complete history, clinical details and neuropathological studies were available. Clinical aspects were grouped into five categories: behavioral and cognitive changes, sleep and alertness, visual impairment, motor disturbances, myoclonus and epilepsy. The neuropathological examination in each case allowed us to evaluate the damage of 13 areas of the central nervous system. Results: Five forms of CJD were identified. The classic form was present in 28 patients (70%), the Heidenhain form was present in five (12.5%), the ataxic form in four (10%), the form with Kuru plaques in two (5%) and the Vacuolar was present in one patient (2.5%). Conclusions: The variety and forms of CJD in Chile do not differ substantially from those found abroad.

Mielinolisis central pontina en trasplante hepático / Central pontine myelinolysis after liver transplantation. Report of five cases

Background: Central Pontine Myelinolysis (CPM) is the most severe neurological complication after liver transplantation and apparently is not related to changes in osmolarity. Aim: To report five transplanted patients with CPM. Patients and Methods: In a series of 27 patients subjected to liver transplantation between 2005 and 2008, we found five patients who developed CPM. Results: All patients presented a severe hepatic encephalopathy. In the absence of alterations in osmolality, they developed, between the second to seventh day after transplantation, a central quadriplegia, hyperreflexia and Babinski sign, with preservation of sensorium. Magnetic resonance imaging showed demyelination of the motor pathway only in the protuberance. Motor recovery first began in the fingers and hands, followed by forearms, toes, feet, arms and finally the legs, defining a somatotopic recovery of the cortico-spinal pathway. Conclusions: This form of regaining motility shows that the selective involvement of the pyramidal tract in CPM, is according to its location in the pons and suggests a local entrapment. It is due to the structural rigidity of the protuberance that limits the expansive requirements of cytotoxic and vasogenic edema, and only affects the long fibers of cortico-spinal tracts, sensitized by encephalopathy. The entrapment syndromes generally preserve the axons, injure myelin and have no inflammatory reactions.

Hallazgos otoneurológicos en pacientes con tinnitus y audiometría tonal clásica normal / Neuro-otological findings in tinnitus patients with normal standard audiometry

Introducción: Los pacientes continnitus y audición normal son poco frecuentes. No hay referencias en la literatura sobre los hallazgos del examen vestibular en este tipo de enfermos. Objetivo: Analizar los hallazgos de la exploración clínica codeo-vestibular en un grupo de pacientes con tinnitus y audición (audiometría tonal clásica) normal. Material y método: Estudio retrospectivo de un grupo de 17 pacientes con tinnitus y audición normal examinados en un período de 10 años; sus resultados se compararon con los de un grupo control de 17 sujetos sin tinnitus y con audición normal. Resultados: En el grupo de pacientes la audiometría tonal clásica era normal y en el examen vestibular la mayoría de ellos (15) mostró una paresia vestibular unilateral en la prueba calórica; en sólo dos ésta era normal. En marcado contraste con el grupo de pacientes, en la mayoría de los sujetos normales (15) la prueba calórica era normal y en 2 se encontró una paresia vestibular unilateral. Conclusión: Se formula la hipótesis que, en nuestro grupo de pacientes, el tinnitus sería el único síntoma de una lesión "subclínica" codeo-vestibular, la cual en la exploración codeo-vestibular se manifestaría sólo por una paresia vestibular.

Introduction: Patients presenting with tinnitus and normal hearing are not frequent. There are no reports in the literature about vestibular test findings in these patients. Aim: To analyze the cochleovestibular clinical examination findings in a group of patients with tinnitus and normal hearing (standard pure-tone audiometry). Material and Method: Retrospective study in a group of 17 patients presenting with tinnitus and normal hearing over a period of 10 years. The results are compared with those from a control group of 17 individuals without tinnitus and with normal hearing. Results: In the tinnitus group, standard pure-tone audiometry was normal; in most of them (n =15) vestibular testing evidenced a unilateral vestibular paralysis on the caloric test. In contrast, in the control group, the majority (n=15) had a normal caloric test; with only two of them presenting unilateral vestibular paralysis. Conclusion: We hypothetize that, in the group of patients studied, tinnitus is the sole symptom of a "subclinic" cochleovestibular lesion, which would be evident only as a vestibular paralysis.

Neurolisteriosis: descripción de siete casos / Neurolisteriosis: description of seven cases

Listeria Monocytogenes is a gram-positive Bacillus that affects immunocompromised patients, newborn, pregnant women and persons over 65 years. Infection is acquired through contaminated food. The Bacillus has predilection for the central nervous system. Its presents most commonly as an acute meningitis, it also presents as a chronic meningitis, cerebritis, rhomboencephalitis, brain and spinal abscess. Diagnosis for L. monocytogenes is made through positive cultures in blood and cerebrospinal fluid (CSF). Magnetic Resonance (MR) also helps to in the diagnosis of neurolisteriosis lesions. We described seven cases with L. Monocytogenes infection during 2007 and 2008, with four cases over the aged of 65 years old. Five presented acute meningitis; two rhomboencephalitis and one patient had meningoencephalitis. Six cases showed inflammatory CSF with pleocytosis with polymorphonuclear prevail and normal glycorrachia. MR showed inflammatory findings in five patients and focal brainstem lesions in two cases, one had acute hydrocephalus due arachnoiditis. Five patients improve clinically and two fatal cases were described. Listeriosis is the third cause of meningitis and should be consider in the differential diagnosis of meningitis with clear fluid, especially with pleocytosis and normal glycorrachia. Other clues of the diagnosis are dizziness with or without nystagmus and brainstem compromise. Arachnoiditis should be avoided with steroidal use. The diagnostic imaging test of choice for brain stem compromise is MR.

La Listeria Monocytogenes es un bacilo Gram-positivo que afecta a pacientes inmunocomprometidos, a niños, embarazadas y personas mayores de 65 años. El modo de adquirirla es la ingestión de alimentos contaminados. El bacilo tiene predilección por el sistema nervioso central, donde su expresión más frecuente es la meningitis aguda, también puede presentarse como meningitis crónica, cerebritis, rombencefalitis, abscesos cerebrales y espinales. El cultivos positivos de L. monocytogenes en muestras de sangre o líquido cefalorraquídeo, permite confirmar el diagnóstico. La Resonancia Magnética de cerebro también contribuye al diagnóstico de las lesiones por neurolisteriosis. Se analizan siete casos de neurolisteriosis ocurridos los a±os 2007 y 2008, entre ellos cuatro pacientes mayores de 65 años. La meningitis aguda fue la forma de presentación en cinco de ellos, dos evolucionaron como rombencefalitis y uno como meningoencefalitis. El LCR fue inflamatorio en seis de los pacientes, con pleocitosis depredominio polinuclear, pero glucorraquia normal. La RM mostró imágenes de aspecto inflamatorio en cinco de los enfermos, dos de ellos tenían lesiones focales del tronco cerebral, uno hizo un hidrocéfalo agudo por aracnoiditis. Cinco pacientes presentaron una evolución clínica favorable y dos fallecieron. Siendo la listeriosis la tercera causa etiológica de meningitis, debe ser considerada en el diagnóstico diferencial de meningitis a líquido claro, especialmente en LCR con abundantes polinucleares y glucosa en rangos normales. Otras claves son la sensación vertiginosa con o sin nistagmus y el compromiso de nervios craneales de origen protuberancial. Debe prevenirse las aracnoiditis con el uso precoz de corticoides. Es obligatorio el estudio con RM en toda sospecha de neurolisteriosis.

Causas atribuidas a eventos de aparente amenaza a la vida del lactante / Causes attributed to apparent life-threatening event: 3 years of experience

Background: An Apparent Life-Threatening Event (ALTE) is an important challenge for the pediatrician, which requires guidelines for finding the etiology and making appropriate clinical decisions. Objective: To describe etiologies and clinical features of ALTE in infants, as determined by a standarized protocol. Methods: A prospective study including infants admitted to the Emergency Room and hospitalized due to an ALTE between May 2002 and May 2005. They were evaluated with an established protocol that considers the episode description, clinical history, and complementary laboratory studies. Results: 109 patients with ALTE and a mean age of 11 weeks had the following symptoms: apnea (100 percent), skin color changes (97 percent), and muscle tone changes (83 percent). 96 percent received CPR maneuvers or strong stimulation maneuvers for ending the episode. Fourteen percent of the cases were idiopathic, while other etiologies included respiratory infections (46 percent), gastroesophageal reflux (16 percent), seizures (6 percent), and urinary tract infections (6 percent). 3 patients expired. Conclusions: With this protocol, based on tools available in most public tertiary hospitals in Chile, we can identify the causes of ALTE similar to those reported in other studies, howeber with a lesser percentage of idiopathic episodes.

Introducción: Un Evento de Aparente Amenaza a la Vida (ALTE) plantea un importante desafío al pediatra, quién debe investigar la etiología para orientar su conducta. Esta labor se facilita con la aplicación de una guía. Objetivo: Describir la presentación clínica y determinar posibles causas de ALTE mediante un protocolo especifico. Pacientes y Método: Estudio prospectivo en lactantes que consultaron en un Servicio de Urgencia y se hospitalizaron por ALTE entre Mayo 2002 a Mayo 2005. Se evaluaron con un protocolo preestablecido considerando la descripción del episodio, antecedentes y estudios complementarios por pasos. Resultados: En 109 pacientes con ALTE, edad promedio 11 semanas, se observó apnea en 100 por ciento y cambio de color en 97 por ciento. El 83 por ciento presentó cambio de tono y en el 96 por ciento se utilizaron maniobras para abortar el episodio. Se consideró idiopático el 14 por ciento de los casos. Las principales causas atribuidas fueron: infecciones respiratorias (46 por ciento), reflujo gastroesofágico (16 por ciento), convulsiones (6 por ciento) e infecciones urinarias (6 por ciento). Fallecieron 3 pacientes. Conclusiones: Mediante este protocolo, que utiliza herramientas disponibles en la mayoría de los hospitales públicos terciarios de nuestro país, se atribuyeron causas similares a las reportadas en otros estudios prospectivos, donde destaca un menor porcentaje de episodios idiopáticos.