Meningitis crónica autoinmune secundaria a meningitis aguda por neumococo: caso clínico / Autoimmune chronic meningitis secondary to pneumococcal meningitis: report of one case

Pneumococcal meningitis produces several inflammatory disorders in susceptible subjects. A worsening of meningitis can occur on the fourth day of evolution in relation with the withdrawal of steroids. Other complications include the development of inflammatory signs in the post-acute stage of infection associated with disseminated vasculitis of the cerebral blood vessels and, even later, an autoimmune chronic meningitis. All these inflammatory complications are well controlled with the use of steroids. We report a 53-year-old woman with pneumococcal meningitis that had a good response to treatment with antibiotics and steroids. On the four day, after the steroids were discontinued, she complained of headache, became confused, and had an abnormal cerebrospinal fluid (CSF), report CT angiography showed signs of arteritis. She improved when the steroids were re-started. She was discharged in good condition but after slow tapering of the steroids over a four-month period she had a relapse of all her symptoms and had a gait disturbance. On readmission, she had an inflammatory CSF, there were no signs of infection and the cerebral MRI showed meningeal thickening with ventricular space enlargement. She improved again with steroids and she is now well on high-dose steroids but deteriorates each time the steroids are stopped. She experienced both acute and sub-acute inflammatory responses and finally developed a chronic meningitis responsive, and is dependent on steroids.

Expresión de O6-metilguanina-ADN-metiltransferasa (MGMT) en pacientes chilenos con glioblastoma multiforme / O6-methylguanine-DNA-methyltransferase (MGMT) expression in patients with glioblastoma multiforme

Background: Patients with Glioblastoma multiforme (GBM) have a five years survival of less than 5%, but the response to chemotherapy with alkylating agents can vary depending on the methylation status of O6-methylguanine-DNA-methyltransferase (MGMT). Genetic testing has limitations for routine use, while immunohistochemistry (IHC) offers a fast and affordable technique but with heterogeneous results in the literature. Aim: To evaluate MGMT expression by IHC in tumor tissue of Chilean patients with GBM. Material and Methods: Tumor samples of 29 patients with a pathological diagnosis of GBM were studied. We performed IHC staining and manual analysis of positive and negative cells for MGMT expression. A cut-off of at least 10% of cells expressing MGMT was used. Demographic and clinical features of patients were obtained from clinical records. Results: The median number of cells counted per case was 692 (interquartile range [IQR] 492-928). Fifteen cases (52%) were positive for MGMT expression. Median overall survival was 5.3 months (IQR 3.4-12-8). The effect of MGMT expression on the therapeutic response was not studied since only 3 patients received chemotherapy. Conclusions: Our results are similar to international reports, but we were not able to determine the association between MGMT expression and therapeutic response.

Leucopatía reversible de la protuberancia: en paciente con SIDA y tratamiento retroviral / Pontine reversible leucopathy in an AIDS patient associated with highly active antiretroviral therapy (HAART): report of one case

Posterior reversible encephalopathy (PRES) is a condition characterized by T2 and FLAIR hyperintensities in magnetic resonance imaging (MRI) studies, localized preferentially in the occipital-parietal white matter regions. Pathological MRI images located in midbrain, pons, medulla and spinal cord, that could be asymptomatic, were recently included in this entity. These images are interpreted as vasogenic edema, which is caused by arterial hypertension or eclampsia, neurotoxicity related to immunosuppressive agents or chemotherapy, among other causes. We report a 25 years old asymptomatic male with AIDS, with normal blood pressure who after initiating highly active antiretroviral therapy (HAART) reported vertigo. The MRI showed a central pontine T2 hyperintensity with diffusion restriction, which was interpreted as a central pontine myelinolysis (CPM), but the lack of motor symptoms made improbable a real demyelination of the pons. The follow-up MRI revealed complete regression of the images. To our knowledge, this case could be the second report of a reversible leucopathy of the pons in a patient with AIDS, were the MRI images also simulated a CPM. This report extends the knowledge around the variability of the pathogenic interpretation of CPM images and their association with HAART.

Cerebritis bifrontal y absceso cerebral por Streptococcus del grupo anginosus, en paciente previamente sano: Caso clínico / Bifrontal cerebritis and brain abscess caused by Sreptococcus anginosus group: Report of one case

The etiology of brain abscesses is mostly polymicrobial. Streptococci and anaerobic bacteria are the most commonly isolated pathogens. We report a previously healthy female without predisposingfactors, presenting with a bifrontal cerebritis caused by a Streptococcus anginosus group infection. The patient developed a brain abscess and a subdural collection with severe intracranial hypertension offatal evolution. The etiologic diagnosis was made culturing the material obtained from the subdural collection. It is presumed that, within the Streptococcus anginosus group, Streptococus intermedius could have been the causing bacteria, given its central nervous system tissue tropism and its predisposition to form brain abscesses.

Microtubule proteins and their post-translational forms in the cerebrospinal fluid of patients with paraparesis associated with HTLV-I infection and in SH-SY5Y cells: An in vitro model of HTLV-I-induced disease

HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is characterized by axonal degeneration of the corticospinal tracts. The specific requirements for transport of proteins and organelles to the distal part of the long axon are crucial in the corticospinal tracts. Microtubule dysfunction could beinvolved in this disease, configuring an axonal transport disease. We measured tubulin and its posttranslational modified forms (acetylated and tyrosinated) in CSF of patients and controls, as well as tau and its phosphorylated forms. There were no significant differences in the contents of tubulin and acetyl-tubulinbetween patients and controls; tyrosyl-tubulin was not detected. In HAM/TSP, tau levels were significantly reduced, while the ratio of pT181/total tau was higher in patients than in controls, this being completely different from what is reported in other neurodegenerative diseases. Phosphorylation at T181 was also confirmed by Mass Spectrometry analysis. Western Blotting with monospecific polyclonal antibodies against pS199, pT205, pT231, pS262, pS356, pS396, pS404 and pS422 did not show differences in phosphorylation in these residues between patients and controls. Treating human SH-SY5Y neuroblastoma cells, a well-known in vitro neurite retraction model, with culture supernatant of MT-2 cells (HTLV-I infected cell line that secretes theviral Tax protein) we observed neurite retraction and an increase in tau phosphorylation at T181. A disruptionof normal phosphorylation of tau protein in T181 could result in its dysfunction, contributing to axonal damage.

Demencia frontotemporal no familiar y epilepsia generalizada / Frontotemporal dementia non familial and generalized epilepsy

Se presenta un paciente de 62 años, sin antecedentes familiares de demencia, que a los 45 años debuta con crisis súbitas de disnea, visión borrosa, caída al suelo y movimientos repetitivos de brazos. Tratado por epilepsia con fenitoína y ácido valproico, repite esporádicamente crisis semejantes. Hace 4 años sus familiares notan cambios de personalidad, irritabilidad y conductas obsesivas. Hace 2 años aparecen episodios de desorientación de días de duración, algunos con alucinaciones auditivas y también fenómenos convulsivos. Ultimamente presenta crisis polimorfas, algunas con prolongada alteración de conciencia, estados catatoniformes y relajación esfinteriana. Examen físico y neurológico sin anormalidades. Evaluación neuropsicológica evidenció consistentes defectos en funciones frontales. EEG mostraron lentitud generalizada y actividad irritativa esporádica en regiones frontotemporales. Atrofia cortical de predominio anterior en CT scan e hipoperfusión fronto-temporal bilateral en SPECT. Exámenes de laboratorio y LCR normales. CONCLUSION: La asociación de DFT con epilepsia, en forma no familiar, sugiere un síndrome neurodegenerativo cortical diferente.

Títulos de anticuerpos anti-VTLV-I en individuos infectados seropositivos / Anti HTLV-I antibody titers in seropositive infected individuals

The aim of this study was to determine anti HTLV-I antibody titers in seropositive symptomatic and asymptomatic infected subjects. One hundred seven infected subjects (47 with spastic paraparesis and 60 asymptomatic) were studied. HTLV-I antibodies were determined using indirect immunofluorescence in cells infected with the retrovirus. The mean titer was 1/234 in asymptomatic subjects and 1/2138 in symptomatic patients (p<0,001). These results suggest an association between HTLV-I antibody titers and clinical stage of infected subjects

Accidente vascular isquémico de la medula espinal: presentación clínica de ocho casos, dos con estudio anatomopatológico / Vascular ischemic accident of the spinal cord: clinical report of 8 cases, 2 with anatomopathological study

Se presentan ocho casos de accidentes vasculares isquémicos de la médula espinal, los que se analizan clinicamente destacando la forma brusca y dolorosa de comienzo, el predominio lesional de la región dorso-lumbar y la frecuente asociación de patología aórtica en estos pacientes. Se destaca la evolución favorable de aquellos casos con síndromes medulares incompletos y con recuperación motora precoz. Se comenta la menor vulnerabilidad de la médula espinal a la isquemia y su posible interpretación fisiopatológica

The biology of neurofilaments and the degenerative disorders of the central nervous system

Los neurofilamentos son uno de los más importantes componentes de las redes estructurales del citoplasma neuronal. Ellos contienen tres polipeptidos con pesos moleculares de 68.000, 160.000 y 200.000. En esta revisión nosotros discutimos su purificación, propiedades químicas, interacciones moleculares, distribución celular y transporte axonal, como también la posible relación de esta estructura con ciertas enfermedades del sistema nervioso central. En este contexto es interesante mencionar que pacientes con encefalopatías espongiformes y Enfermedad de Alzheimer familiar, presentan títulos altos de autoanticuerpos dirigidos a la subunidad de 200.000 del neurofilamento

Un caso de enfermedad de Creutzfeldt-Jakob de comienzo agudo postraumático / A case of Creutzfeldt-Jakob disease with postraumatic acute onset

Comunicamos un caso de enfermedad de Creutzfeldt-Jakob (ECJ) verificada por biopsia cerebral y cuyo comienzo clínico ocurrió en forma abrupta pocas horas después de un traumatismo encefalocraneano no complicado. Se discute la posible relación entre el traumatismo y el desarrollo clínico de la ECJ, afección que tiene una bien conocida etiología transmisible. Se compara este caso con los pocos casos similares aparecidos en la literatura pertinente

Evolución de la miastenia gravis en relación a las características histológicas del timo / Course of myasthenia gravis according to histological characteristics of the thymus

En 64 pacientes de miastenia gravis se estudia la característica histológica del timo y se la correlaciona con la evolución post-timectomía a los 3 años o más. Se realiza un estudio cuantitativo de la cantidad de tejido tímico (TT), folículos germinativos (FG), corpúsculos de Hassall celulares (CHC) y corpúsculos de Hassall atróficos (CHA). Se observa que hay significativa mejoría en aquellos pacientes que tienen un timo con abundante TT y poca cantidad de FG y CHC, no siendo significativo el recuento de CHA. Se hace especial relevancia de los CHC como componentes habituales de los enfermos que no mejoran, relacionándolos con la producción de la hormona tímica

Transmisión experimental de ocho casos de enfermedad de Creutzfeldt-Jakob al animal de laboratório / Experimental transmission of 8 cases of Creutzfeldt-Jakob disease to laboratory animals

Comunicamos la transmisión experimental de 8 casos de enfermedad de Creutzfeldt-Jakob (ECJ) con verificación histológica ocurridos en Chile (4 casos esporádicos y 4 casos familiares). Seis pacientes desarrollaron la forma clásica de la ECJ, uno correspondía a la forma ataxo-cerebelosa y otro era un caso atípico de comienzo agudo. Dos cobayos y 9 monos del Nuevo Mundo desarrollaron una encefalopatía espongiforme experimental luego de la inoculación intracerebral, intramuscular e intraperitoneal de tejido cerebral de los casos humanos. Los 2 cobayos murieron bruscamente, sin presentar signos neurológicos previos 14 y 18 meses después de inoculados. Dos monos capuchinos 1 mono araña y 6 monos ardilla desarrollaron la enfermedad experimental luego de un período de incubación silenciosa de 15 a 44 meses y fueron sacrificados 1 a 2 meses después. Es interesante destacar el hecho de que en una de estas exitosas transmisiones experimentales el inóculo consistió en tejido cerebral fijado en formalina y que había sido mantenido a temperatura ambiente durante 4 años. Animales inoculados con tejido cerebral de otros 5 casos de ECJ diagnosticados en Chile entre 1980 y 1983 aún bajo observación

Hemorragia talámica: estudio anatomoclínico de 25 casos / Thalamic hemorrhage: anatomoclinical study of 25 cases

Se presentan 25 casos de hemorragias talámicas con estudio neuropatológico. Se definen cuatro formas clínico-patológicas de presentación de acuerdo al tamaño y propagación de las lesiones. Se analiza el pronóstico de cada grupo, observándose que la causa de muerte en las hemorragiass pequeñas fue consecuencia de una disfunción hipotalámica, adquiriendo especial relieve la hemorragias digestiva. Resalta en esta serie, las alteraciones del habla y del lenguaje, así como el compromiso de la oculomotilidad, elementos que ayudan a configurar los diversos síndromes clinicopatológicos

Demencia límbica: presentación de três casos / Limbic dementia: report of 3 cases

Se presentan tres enfermos que por diferente causa se lesionan el lóbulo límbico y el lóbulo temporal, desarrollando un síndrome caracterizado por pérdida del control instintivo, desenfreno oral y sexual, apagamiento o pérdida de la afectividad y graves alteraciones de la memoria. Uno de los enfermos tiene estudio neuropatológico y los otros dos evolucionan hacia una compensación, logrando el control instintivo y recuperando parcialmente los defectos de memoria. Sin embargo, mantienen un defecto residual con las características del daño orgánico inespecífico que los inhabilita definitivamente. Tanto el desarrollo del síndrome como su defecto final determinan un perfil evolutivo y clínico que se comenta, definiéndolo como demencia límbica