Neumonía asociada a ventilación mecánica en pacientes con neumonía grave por SARS-CoV-2 / Ventilation associated pneumonia in patients with severe SARS-CoV-2 pneumonia

Introducción: Los pacientes con COVID-19 pueden evolucionar hacia una falla respiratoria aguda grave y requerir ventilación mecánica invasiva (VMI). La complicación más frecuente en estos pacientes es la neumonía asociada a ventilación mecánica (NAVM), con incidencias reportadas más altas que en la época pre-COVID. El objetivo de este estudio es reportar la incidencia, tasa de incidencia y microbiología de la NAVM en pacientes en VMI con COVID-19. Métodos: Se incluyeron a todos los pacientes con neumonía grave y PCR (+) para SARS-CoV-2 que ingresaron y requirieron VMI entre marzo y julio del 2021 en el Instituto Nacional del Tórax (INT). Se recolectaron datos demográficos, clínicos y de laboratorio de la ficha electrónica. Se registraron y caracterizaron los casos de neumonía asociado a la ventilación mecánica. Resultados: Se incluyeron 112 pacientes de los cuales el 42,8% presentó NAVM, con una tasa de incidencia de 28,8/1.000 días de VMI. Los microorganismos aislados más frecuentes fueron Klebsiella pneumoniae (29,6%), Staphylococcus aureus (21,8%) y Pseudomonas aeruginosa (12,5%). Los pacientes que cursaron NAVM estuvieron casi el doble de tiempo en VMI, pero sin presentar aumento de la mortalidad. Conclusión: La NAVM es una complicación frecuente en los pacientes con neumonía grave asociada a COVID-19. La microbiología de estas entidades no ha cambiado respecto a la era pre-pandémica. Estos resultados cobran relevancia en el inicio y suspensión de antibióticos en este grupo de pacientes.

Introduction: Patients with COVID-19 can progress to severe acute respiratory failure and require invasive mechanical ventilation (IMV). The most frequent complication in these patients is ventilator-associated pneumonia (VAP), with higher reported incidences than in the pre-COVID era. The objective of this study is to report the prevalence, incidence rate and microbiology of VAP in patients on IMV with COVID-19. Methods: Patients with severe pneumonia and PCR (+) for SARS-CoV-2 who were admitted to IMV between march and july 2021 at the Instituto Nacional del Tórax (Chile) were included. Demographic, clinical and laboratory data from electronic records were collected. Cases of pneumonia associated with mechanical ventilation were recorded and characterized. Results: 112 patients were included, 42.8% of them presented VAP with an incidence rate of 28.8/1,000 IMV days. The most frequent isolated microorganisms were Klebsiella pneumoniae (29.6%), Staphylococcus aureus (21.8%) and Pseudomonas aeruginosa (12.5%). Patients who underwent VAP spent almost twice as long on IMV, although they had not increase in mortality. Conclusion: VAP is a common complication in patients with severe pneumonia associated with COVID-19. The microbiology of these entities has not changed from the pre-pandemic era. These results become relevant in the initiation and suspension of antibiotics in this group of patients.

Utilidad diagnóstica del dímero-D en el tromboembolismo pulmonar de pacientes COVID-19 / DiagnosticutilityofD-dimerin pulmonarythromboembolism in COVID-19 patients

Resumen Introducción: El aumento de la concentración de dímero-D en pacientes COVID-19 se ha asociado a mayor gravedad y peor pronóstico; sin embargo, su rol en predecir el diagnóstico de tromboembolismo pulmonar (TEP), aún es incierto. Objetivo: Evaluar la utilidad del dímero-D plasmático en el diagnóstico de TEP en pacientes con COVID-19. Pacientes y Métodos: Estudio observacional analítico. Se incluyó a pacientes COVID-19 que tenían una angiotomografía computada de tórax (AngioTAC). Se registraron datos clínicos, niveles plasmáticos de dímero-D de ingreso y previo al momento de realizar la AngioTAC. Se identificó la presencia o ausencia de TEP. Resultados: Se incluyeron 163 pacientes; 37(23%) presentaron TEP. Al comparar la serie de pacientes con TEP versus sin TEP, no se encontraron diferencias significativas en características clínicas, ni mortalidad. Hubo diferencias significativas en el nivel plasmático del dímero-D previo a realizar la AngioTAC (3.929 versus 1.912 μg/L; p = 0,005). El área bajo la curva ROC del dímero-D para TEPfue de 0,65. El mejor punto de corte del dímero-D fue de 2.000 μg/L, con una baja sensibilidad y valor predictivo positivo. El valor de corte con el mejor valor predictivo negativo (VPN)fue de 900 μg/L (96%), el cual fue mejor que la estrategia de corte de dímero D ajustado por edad (VPN 90%). Conclusión: La capacidad discriminativa del dímero D para diagnosticar TEP fue baja. En cambio, el dímero D mantiene un alto valor predictivo negativo para descartar TEP, el cual es mayor al valor descrito clásicamente en los pacientes no COVID.

Introduction: Increased D-dimer concentration in COVID-19 patients has been associated with greater severity and worse prognosis; however its role in predicting the diagnosis of pulmonary thromboembolism (PTE), is still uncertain. Objective: To evaluate the usefulness of plasma D-dimer in the diagnosis of PTE in patients with COVID-19. Method: Analytical observational study. COVID-19 patients who had a chest computed tomography angiography (CTA) were included. Clinical data, Ddimer plasma levels on admission and prior to CTA were recorded. The presence or absence of PTE was identified. Results: 163 patients were included, 37 (23%) presented PTE. After comparing the series of patients with PTE versus the series without PTE, no significant differences were found in clinical characteristics or mortality. There were significant differences in the plasma level of D-dimer prior to performing CTA (3,929 μg/L versus. 1,912 μg/L; p = 0.005). The area under the D-dimer ROC curve for PTEprediction was 0.65. The best D-dimer cutoffpoint was 2.000μg/L, with a low sensitivity and positivepredictive value. The cutoff value with the best negativepredictive value (NPV) was 900 μg/L (96%), which was better than the age-adjusted D-dimer cutoff strategy (NPV 90%). Conclusion: The discriminative ability of D-dimer to diagnose PTE was low. In contrast, D-dimer maintains a high negative predictive value to rule out PTE, which is higher than the value classically described in non-COVID patients.

Caracterización clínica y microbiológica de pacientes con trazas en Xpert MTB/RIF Ultra / Clinical and microbiological characterization of patients with Xpert MTB/RIF Ultra traces

INTRODUCCIÓN: El Xpert MTB/RIF Ultra (Ultra) ha mejorado dramáticamente el diagnóstico de la tuberculosis (TBC). Con él ha nacido la categoría de trazas, que es la menor carga bacilar detectable por este examen. OBJETIVO: Describir las características clínicas de los pacientes con presencia de trazas en el Ultra y evaluar la confirmación de la TBC como diagnóstico clínico. MATERIALES Y MÉTODOS: Estudio descriptivo de serie de casos. Se extrajo la información de fichas clínicas de pacientes con positividad a trazas. Se confrontaron datos clínicos, microbiológicos e histopatológicos. RESULTADOS: Se analizaron 21 pacientes. La edad promedio fue de 52 años. Todos los casos presentaron baciloscopias negativas. Cuatro cultivos en medio líquido MGIT fueron positivos, dos en pleura parietal, uno en líquido pleural y otro en expectoración. En pleura parietal, tres casos presentaron granulomas con necrosis caseosa y un granuloma esbozos de necrosis. En tejido pulmonar se observaron dos casos con granulomas con esbozos de necrosis y dos con granulomas no necrotizantes. Tres pacientes tenían el antecedente de TBC previa, se interpretó la positividad de trazas en ellos como falsos positivos. Finalmente se diagnosticaron 13 casos como TBC activa, donde cinco de ellos fueron TBC pleurales. La mayor concordancia clínica, microbiológica e histopatológica fue en muestras de líquido y tejido pleural. DISCUSIÓN: Se debe interpretar con cautela los hallazgos de esta prueba en muestras de vía aérea; el análisis multidisciplinario (clínica, imágenes, microbiología, histología) es crucial en las decisiones de nuestras conductas clínicas futuras. El hallazgo de trazas en pleura tiene, a nuestro parecer, un alto valor diagnóstico en el estudio de la tuberculosis en esta localización.

INTRODUCTION: Xpert MTB/RIF Ultra has dramatically changed the diagnosis of tuberculosis. A new category called traces appeared, which is the smallest amount of bacillar load detectable. OBJECTIVE: Describe the clinical characteristics of patients that present traces in Xpert MTB/RIF Ultra test, and to evaluate the confirmation of tuberculosis as clinical diagnosis. METHODS: We perform a descriptive case series study. Information was recovered from clinical records of patients with positive test for traces. Clinical, histopathological and microbiological results were confronted. RESULTS: Twenty one patients were analyzed. The mean age was 52 years-old. All cases had negative smear microscopy and four MGIT cultures were positive, two in pleural fluid and another in sputum. In parietal pleura, three cases presented granulomas with caseous necrosis, and one showed granuloma with very little necrosis. In pleural tissue we observed two cases of granulomas with traces of necrosis and two with non-necrotizing granulomas. Three patients had history of previous tuberculosis and positive traces, the test was interpreted as a false positive result. Finally, active tuberculosis was diagnosed in 13 cases, and five of them were pleural tuberculosis. The highest clinical, microbiological and histopathological agreement was in fluid and pleural tissue samples. DISCUSSION: The findings of Xpert MTB/RIF Ultra in airway samples must be interpreted carefully. Multi-disciplinary analysis is crucial in future clinical decisions. The finding of traces in pleura has, in our opinion, a high diagnostic value in the study of tuberculosis in this location.

Biomarcadores en tuberculosis / Biomarkers in tuberculosis

Resumen Los métodos diagnósticos clásicos para la tuberculosis son de baja sensibilidad o son muy lentos en la obtención de resultados (baciloscopía, cultivo de Koch). De ahí nace la necesidad de nuevos métodos diagnósticos para esta enfermedad. Los biomarcadores surgen como una opción a esta problemática, con un buen rendimiento diagnóstico, costo y accesibilidad. Ellos permiten identificar la respuesta inflamatoria y/o metabólica del huésped, extrapolando la presencia de Mycobacterium tuberculosis; o identifican moléculas propias del patógeno. En la presente revisión se describen biomarcadores que presentan un buen rendimiento diagnóstico basados en metodologías de investigación de alto nivel (estudio de cohortes, prospectivos, muestreo consecutivo o aleatorizado, comparación de rendimiento diagnóstico frente a cultivo). Es necesario el desarrollo de estas nuevas técnicas con el fin de realizar el diagnóstico precoz de la enfermedad y lograr así su tan ansiada eliminación.

The classical laboratory diagnostic methods for tuberculosis have a low sensitivity or take a long time to know their results. New methods are underway. Biomarkers are a good option to improve our diagnostic approach to this disease. They have good performance, low cost and accessibility. They identify a patient's inflammatory or metabolic response to Mycobacterium Tuberculosis or identifies molecules that are typical of the pathogen. In this paper we sum up the biomarkers with a good diag-nostic performance described in well design investigations. Early diagnosis with these new techniques should contribute to the elimination of the disease.

Factores asociados al ataque cerebrovascular isquémico entre los años 2013 a 2016, un estudio de casos y controles / Factors associated with ischaemic cerebrovascular accidents between the years 2013 and 2016: A case-control study

Resumen Objetivo: Determinar los factores asociados al ataque cerebrovascular isquémico en el servicio de urgencias de la Clínica Especializada Los Andes, de la ciudad de Tunja, entre los años 2013 a 2016. Pacientes y métodos: Estudio de casos y controles; los casos correspondieron a 97 pacientes con ataque cerebrovascular isquémico (infarto cerebral isquémico y accidente isquémico transitorio) y los controles a 291 pacientes sin ataque cerebrovascular isquémico que ingresaron a urgencias entre los años 2013 a 2016. Resultados: El sexo femenino correspondió al 56,7% (55) de los casos y al 54,6% de los controles (154) (p = 0,069). La media de edad en el grupo caso fue de 73,7 años ENT#091;DE: 10,5 añosENT#093; y en los controles de 64,5 años ENT#091;DE: 11,3 añosENT#093;. Los factores asociados al ataque cerebrovascular isquémico fueron: antecedente de ataque cerebrovascular isquémico ENT#091;OR 7,7 IC 95% 3,2; 18 p= 0,000ENT#093;, tabaquismo ENT#091;OR 4,4 IC 95% 1,1; 18 p= 0,022ENT#093;, dislipidemia ENT#091;OR 3 IC 95% 1,2; 7,5 p= 0,017ENT#093;, edad igual o mayor a 70 años ENT#091;OR 2,3 IC 95% 1,3; 4,1 p= 0,002ENT#093; e hipertensión arterial ENT#091;OR 1,8 IC 95% 1,06; 3,3 p= 0,029ENT#093;. Conclusiones: Los factores asociados al ataque cerebrovascular isquémico fueron, en orden de importancia, antecedente de ataque cerebrovascular isquémico, tabaquismo, dislipidemia, edad igual o mayor a 70 años E hipertensión arterial.

Abstract Objective: To determine the factors associated with ischaemic cerebrovascular accidents (ICVA) in the Emergency Department of the Andes Specialist Clinic of the city of Tunja, between the years 2013 and 2016. Patients and methods: A case-control study was conducted in which the cases consisted of 97 patients with ICVA (ischaemic cerebral infarction and transient ischaemic accident), and the controls were 291 patients with no ICVA, who were admitted to the Emergency Department between the years 2013 and 2016. Results: There were 56.7% (55) females in the cases, and 54.6% (154) in the controls (P=.069). The mean age of the cases was 73.7 years ENT#091;SD: 10.5 yearsENT#093;, and 64.5 years ENT#091;SD: 11.3 yearsENT#093; in the controls. The factors associated with ICVA were: a history of ICVA ENT#091;OR; 7.7, 95% CI; 3.2-18, P=.000ENT#093;, smoking ENT#091;OR; 4.4, 95% CI; 1.1-18, P=.022ENT#093;, dyslipidaemia ENT#091;OR; 3, 95% CI; 1.2-7.5, P=.017ENT#093;, age equal to or greater than 70 years ENT#091;OR; 2.3, 95% CI; 1.3-4.1, P=.002ENT#093;, and arterial hypertension ENT#091;OR; 1.8, 95% CI; 1.06-3.3, P=.029ENT#093;. Conclusions: The factors associated with ischaemic cerebrovascular accident were, in order of importance, a history of ischaemic cerebrovascular accident, smoking, dyslipidaemia, age equal to or greater than 70 years, and arterial hypertension.

Encefalopatía traumática crónica, definición, diagnóstico y prevención: revisión de la literatura / Chronic traumatic encephalopathy, definition, diagnosis and prevention: review of literature

La encefalopatía traumática crónica (ETC) es una enfermedad neurodegenerativa que se produce como consecuencia traumatismos cerebrales repetitivos; concusiones, que son un síndrome clínico que se caracteriza por una alteración de la función cerebral. Una concusión, bajo su estricta definición, no debiese causar cambios estructurales en el cerebro por lo que no sería visible a través de imágenes, sí existen cambios a nivel microscópicos, bioquímicos y biomecánicos. La mayoría de los pacientes tienen completa resolución de sus síntomas dentro de 10 días (90 por ciento), pero existe un pequeño porcentaje que persiste con estos, pudiendo presentarse como un síndrome postconcusional, síndrome de segundo impacto o una encefalopatía traumática crónica. La ETC se caracteriza por la acumulación de prot-tau hiperfosforilada en neuronas y astrocitos. Estas se van a presentar en forma de ovillos o hilos neurofibrilares. En etapas iniciales las encontraremos de forma focalizada en la corteza frontal y en las formas más severas su distribución será más generalizada, distribuyéndose en la mayoría de las regiones del cerebro. Su diagnóstico se realiza a través de histopatología, por lo que hasta el momento sólo se ha logrado post-mortem. Se está trabajando en nuevas tecnologías asociadas a biomarcadores y PET para lograr una diagnostico premortem. El mayor énfasis en el manejo de esta taupatía es la prevención y adecuado manejo de las concusiones.

Chronic Traumatic Encephalopathy (CTE) is a neurodegenerative disease which is produced as a consequence of repeated brain trauma: concussions, which are a clinical syndrome characterized by an alteration in brain functions. A concussion, understrict definition, should not cause structural changes to the brain. Therefore, it would not be possible to see through images if there were changes at a microscopic, biochemical level. Most patients see their symptoms completely resolved within 10 days (90 percent), but there is a small percentage which persists, and these might cause a post-concussional syndrome, second impact syndrome of chronic traumatic encephalopathy. CTE is characterized by the accumulation of hyper-phosphorylated Tau protein in neurons and astrocytes. These appear in the form of neurofibrillary tangles. During the initial stages they are focalized in the frontal cortex and, in more severe cases, their distribution is more generalized, spreading through the majority of the regions in the brain. It is diagnosis is done through histopathology. Thus, it has only been possible to do post mortem. New technologies associated with bio-markers and PET are being worked on to achieve a pre-mortem diagnosis. The greatest emphasis in the handling of this tauopathy lies in the prevention and the adequate handling of concussions.

Cotidiano del profesional de enfermería, en el cuidado del adulto mayor / Daily nursing professional in the care of the elderly

Introducción: El cuidado del adulto mayor disfuncional o dependiente, es un trabajo complejo que requiere paciencia y gusto de ayudar, ante ello es importante tomar en cuenta que las enfermeras (os) que brindan su servicio hacia este grupo etario en su día a día se enfrentan a distintos retos en su área de trabajo o incluso en su sociedad, mismos que se convierten en factores estresantes y colocan al profesional de enfermería en riesgo de adquirir trastornos de salud. Sin embargo, existen también elementos que permiten que el personal de enfermería pueda mantener un cuidado humano dirigido al adulto mayor, entre ellos se encuentran valores, la empatía y el apego. Objetivos: Analizar el cotidiano del profesional de enfermería en el cuidado dirigido a adultos mayores e identificar los factores que favorecen u obstaculizan el cuidado del profesional de enfermería a los adultos mayores hospitalizados. Los autores del fundamento teórico son Henri Lefebvre y Jean Watson. Estudio cualitativo, descriptivo, se realizaron entrevistas en profundidad a once licenciados en enfermería. Resultados: Se encontraron dos categorías con sus correspondientes subcategorías: 1. Praxis del cuidado transpersonal al adulto mayor (1.1 Tolerancia y respeto, 1.2 Empatía y relación de ayuda-confianza y 1.3 El tiempo y la creación de lazos afectivos) y Retos en el cotidiano del cuidado del adulto mayor (2.1 Sobrecarga de trabajo en el cotidiano, 2.2 Falta de recursos para la praxis diaria, 2.3 Espacio compartido con familiares del adulto mayor y 2.4 Falta de reconocimiento social ). Consideraciones finales: En el cotidiano del profesional de enfermería se encuentran distintos factores externos que pueden obstaculizar su sano desempeño como trabajador, entre ellos la sobrecarga de trabajo, la falta de recursos e incluso la falta de reconocimiento social sobre su labor; sin embargo, la praxis del cuidado tiene una naturaleza de humanismo respaldada por los valores de formación de cada profesional que les permite otorgar un cuidado de calidez.

The care of the dysfunctional or dependent older adult is a complex task that requires patience and a willingness to help, before it is important to take into account that the nurses who offer their services to this age group in their daily routine face different challenges in their area of work or even in their society, which become stressors and place the nursing professional at risk of acquiring health disorders However, there are also elements that allow nursing staff to maintain human care directed to the elderly, including values, empathy and attachment. Objectives: To analyze the daily routine of the nursing professional in the care directed to the elderly and to determine the factors that favor or hinder the care of the nursing professional to hospitalized older adults. The authors of the theoretical foundation are Henri Lefebvre and Jean Watson. Qualitative, descriptive study, interviews were conducted in depth to eleven graduates in nursery.Results: There were two categories with their corresponding subcategories: 1. Praxis of transpersonal care for the elderly (1.1 Tolerance and respect, 1.2 Empathy and good treatment and 1.3 Time and the creation of affective bonds) and Challenges in the daily care of the (2.1 Workload in daily life, 2.2 Lack of resources for daily praxis, 2.3 Shared space with relatives of the elderly and 2.4 Lack of social recognition) Final considerations: In the daily routine of the nursing professional are different external factors that may hinder their healthy performance as a worker, including work overload, lack of resources and even lack of social recognition of their work; However, the praxis of care has a nature of humanism backed by the values of training of each professional that allows them to provide a warmth care.

Videocâmeras em biotérios de experimentação: importante ferramenta no controle da contaminação ambiental na microbiota de camundongos / Interference of environmental contamination in microbiota of mice in experimental facilities

O objetivo do presente estudo foi verificar a influência da contaminação ambiental na microbiota dos animais utilizados em experimentação, usando-se videocâmera como ferramenta de controle, a partir da comparação de dois biotérios de experimentação, sendo um protegido com presença de videocâmeras (A) e o outro não (B), quanto ao padrão microbiológico dos camundongos. Para os testes bacteriológicos, foram utilizadas amostras de 222 animais do biotério A e 236 do biotério B; para os testes virológicos, 119 do biotério A e 236 do biotério B; já para os exames parasitológicos, 158 do biotério A e 316 do biotério B. Os dados foram submetidos à análise descritiva e ao teste do Qui-quadrado. Verificou-se uma maior ocorrência de microrganismos e de parasitas no biotério não protegido pelas videocâmeras. Klebsiella pneumoniae, Pasteurella sp. e Pseudomonas sp. foram encontradas nos animais de ambos os biotérios, ao passo que vírus e parasitos só foram detectados nos animais no biotério não protegido. Dentre os vírus, nos animais infectados, o de maior ocorrência foi o Vírus da Hepatite de Camundongos (MHV) e, dentre os parasitos, o de maior ocorrência foi Syphacia sp. Concluiu-se que o biotério protegido foi capaz de garantir padrões microbiológicos mais adequados para a experimentação animal, que as videocâmeras são importantes ferramentas de controle e que a prática da biossegurança deve ser constante nas instituições de pesquisa.

The aim of this study was to investigate the influence of environmental contamination in the microbiota of animals used in experimentation, from the comparison of two experimental animal facilities, one protected with video cameras (A) and one not protected with video cameras (B). Bacteria, viruses and endoparasites have been investigated in both facilities, according to the methodology proposed for each agent. For the bacteriological tests, a sample of 222 animals in facility A and 236 from facility B was used; for the virological tests, 119 from facility A and 236 from facility B; and for parasitological examination, 158 from facility A and 316 from facility B. The data were submitted to descriptive analysis and to the Chi-square test. The results indicated a higher occurrence of microrganisms and parasites in animals from the unprotected facility. Klebsiella pneumoniae, Pasteurella sp. and Pseudomonas sp. could be detected in the animals from both facilities, whereas viruses and parasites were found only in the unprotected housed mice. Among the viruses in infected animals the most common was the occurrence of Mice Hepatitis Virus (MHV) and among the parasites, the predominant was Syphacia sp. It was concluded that the protected facility was able to ensure microbiological standards more suitable for animal testing, video cameras are important control tools, and the practice of biosecurity must be constant in research institutions.

Early neonatal echocardiographic findings in an experimental rabbit model of congenital diaphragmatic hernia

This study aimed to demonstrate that congenital diaphragmatic hernia (CDH) results in vascular abnormalities that are directly associated with the severity of pulmonary hypoplasia and hypertension. These events increase right ventricle (RV) afterload and may adversely affect disease management and patient survival. Our objective was to investigate cardiac function, specifically right ventricular changes, immediately after birth and relate them to myocardial histological findings in a CDH model. Pregnant New Zealand rabbits underwent the surgical procedure at 25 days of gestation (n=14). CDH was created in one fetus per horn (n=16), and the other fetuses were used as controls (n=20). At term (30 days), fetuses were removed, immediately dried and weighed before undergoing four-parameter echocardiography. The lungs and the heart were removed, weighed, and histologically analyzed. CDH animals had smaller total lung weight (P<0.005), left lung weight (P<0.005), and lung-to-body ratio (P<0.005). Echocardiography revealed a smaller left-to-right ventricle ratio (LV/RV, P<0.005) and larger diastolic right ventricle size (DRVS, P<0.007). Histologic analysis revealed a larger number of myocytes undergoing mitotic division (186 vs 132, P<0.05) in CDH hearts. Immediate RV dilation of CDH hearts is related to myocyte mitosis increase. This information may aid the design of future strategies to address pulmonary hypertension in CDH.

Seguimiento endoscópico e histológico post ablación con argón plasma del esófago de Barrett extenso en pacientes sometidos a tratamiento quirúrgico previo / Argon plasma ablation of extensive Barrett esophagus: experience in 19 patients

Background: Endoscopic argon plasma ablation of Barrett esophagus decreases the risk of future esophageal cancer development. Aim: To assess the endoscopic regression of columnar epithelium and the presence of intestinal metaplasia among patients operated for Barrett esophagus and subjected to argon plasma ablation. Patients and Methods: In 19 patients with extensive Barrett esophagus subjected to a Nissen fundoplication, Barrett esophagus was endoscopically ablated with argon plasma. Patients were assessed 6 and 12 months after surgery to evaluate the regression of columnar epithelium and the presence of intestinal metaplasia. Results: One, two and three ablation sessions were carried out in 10, three and six patients, respectively. Three patients had complications. The initial length of columnar epithelium segment was 52 +/- 15.6 mm and decreased to 22.6 +/- 10.6 mm (p < 0.05). In 12 patients, there was absence of intestinal metaplasia on follow up, in six it persisted (one of them with "buried cells") and in one patient, dysplasia appeared. Conclusions: Endoscopic argon plasma ablation may have a complementary therapeutic role for the regression of columnar epithelium in Barrett esophagus.

Introducción: Pacientes con esófago de Barrett extenso presentan un riesgo de cáncer. De allí surge la posibilidad de someter a estos pacientes a ablación con argón plasma por vía endoscópica para disminuir este riesgo de desarrollar un adenocarcinoma. Objetivo: Evaluar la regresión endoscópica del epitelio columnar y la presencia de metaplasia intestinal en pacientes operados por esófago de Barrett y sometidos a ablación con argón plasma. Material y Método: Se incluyen 19 pacientes en este estudio, todos ellos con esófago de Barrett extenso confirmado por endoscopia e histología, los cuales se someten a ablación con argón plasma por vía endoscópica. Estos pacientes se controlaron con endoscopia e histológicamente a los 6 meses y al año de operados para evaluar la regresión del área con epitelio columnar y precisar la presencia histológica de metaplasia intestinal. Resultados: En 10 pacientes se efectuó 1 sesión de ablación, en 3 pacientes 2 sesiones y en 6 pacientes se efectuó 3 sesiones de ablación. Tres pacientes presentaron complicaciones. El largo de las lengüetas de epitelio columnar inicial fue de 52 +/- 15,6 mm el cual disminuyó a 22,6 +/- 10,6 mm (p < 0,05). El seguimiento histológico reveló ausencia de metaplasia intestinal en 12 pacientes (63,1 por ciento) persistencia de metaplasia en 6 pacientes (1 de ellos con células en submucosa, "buried cells") y un paciente con aparición de displasia. Conclusión: La ablación con argón plasma puede tener un rol en el tratamiento complementario a la cirugía para mejorar la regresión del epitelio columnar y disminuir los riesgos de presentar un adenocarcinoma de Barrett.

Antigen-presenting cells transfected with Hsp65 messenger RNA fail to treat experimental tuberculosis

In the last several years, the use of dendritic cells has been studied as a therapeutic strategy against tumors. Dendritic cells can be pulsed with peptides or full-length protein, or they can be transfected with DNA or RNA. However, comparative studies suggest that transfecting dendritic cells with messenger RNA (mRNA) is superior to other antigen-loading techniques in generating immunocompetent dendritic cells. In the present study, we evaluated a new therapeutic strategy to fight tuberculosis using dendritic cells and macrophages transfected with Hsp65 mRNA. First, we demonstrated that antigen-presenting cells transfected with Hsp65 mRNA exhibit a higher level of expression of co-stimulatory molecules, suggesting that Hsp65 mRNA has immunostimulatory properties. We also demonstrated that spleen cells obtained from animals immunized with mock and Hsp65 mRNA-transfected dendritic cells were able to generate a mixed Th1/Th2 response with production not only of IFN-γ but also of IL-5 and IL-10. In contrast, cells recovered from mice immunized with Hsp65 mRNA-transfected macrophages were able to produce only IL-5. When mice were infected with Mycobacterium tuberculosis and treated with antigen-presenting cells transfected with Hsp65 mRNA (therapeutic immunization), we did not detect any decrease in the lung bacterial load or any preservation of the lung parenchyma, indicating the inability of transfected cells to confer curative effects against tuberculosis. In spite of the lack of therapeutic efficacy, this study reports for the first time the use of antigen-presenting cells transfected with mRNA in experimental tuberculosis.

Differences in synthesis and absorption of cholesterol of two effective lipid-lowering therapies

Effective statin therapy is associated with a marked reduction of cardiovascular events. However, the explanation for full benefits obtained for LDL cholesterol targets by combined lipid-lowering therapy is controversial. Our study compared the effects of two equally effective lipid-lowering strategies on markers of cholesterol synthesis and absorption. A prospective, open label, randomized, parallel design study, with blinded endpoints, included 116 subjects. We compared the effects of a 12-week treatment with 40 mg rosuvastatin or the combination of 40 mg simvastatin/10 mg ezetimibe on markers of cholesterol absorption (campesterol and β-sitosterol), synthesis (desmosterol), and their ratios to cholesterol. Both therapies similarly decreased total and LDL cholesterol, triglycerides and apolipoprotein B, and increased apolipoprotein A1 (P < 0.05 vs baseline for all). Simvastatin/ezetimibe increased plasma desmosterol (P = 0.012 vs baseline), and decreased campesterol and β-sitosterol (P < 0.0001 vs baseline for both), with higher desmosterol (P = 0.007) and lower campesterol and β-sitosterol compared to rosuvastatin, (P < 0.0001, for both). In addition, rosuvastatin increased the ratios of these markers to cholesterol (P < 0.002 vs baseline for all), whereas simvastatin/ezetimibe significantly decreased the campesterol/cholesterol ratio (P = 0.008 vs baseline) and tripled the desmosterol/cholesterol ratio (P < 0.0001 vs baseline). The campesterol/cholesterol and β-sitosterol/cholesterol ratios were lower, whereas the desmosterol/cholesterol ratio was higher in patients receiving simvastatin/ezetimibe (P < 0.0001 vs rosuvastatin, for all). Pronounced differences in markers of cholesterol absorption and synthesis were observed between two equally effective lipid-lowering strategies.

Angiotensin II type 1 receptor blockade partially attenuates hypoxia-induced pulmonary hypertension in newborn piglets: relationship with the nitrergic system

The objective of this study was to observe possible interactions between the renin-angiotensin and nitrergic systems in chronic hypoxia-induced pulmonary hypertension in newborn piglets. Thirteen chronically instrumented newborn piglets (6.3 ± 0.9 days; 2369 ± 491 g) were randomly assigned to receive saline (placebo, P) or the AT1 receptor (AT1-R) blocker L-158,809 (L) during 6 days of hypoxia (FiO2 = 0.12). During hypoxia, pulmonary arterial pressure (Ppa; P < 0.0001), pulmonary vascular resistance (PVR; P < 0.02) and the pulmonary to systemic vascular resistance ratio (PVR/SVR; P < 0.05) were significantly attenuated in the L (N = 7) group compared to the P group (N = 6). Western blot analysis of lung proteins showed a significant decrease of endothelial NOS (eNOS) in both P and L animals, and of AT1-R in P animals during hypoxia compared to normoxic animals (C group, N = 5; P < 0.01 for all groups). AT1-R tended to decrease in L animals. Inducible NOS (iNOS) did not differ among P, L, and C animals and iNOS immunohistochemical staining in macrophages was significantly more intense in L than in P animals (P < 0.01). The vascular endothelium showed moderate or strong eNOS and AT1-R staining. Macrophages and pneumocytes showed moderate or strong iNOS and AT1-R staining, but C animals showed weak iNOS and AT1-R staining. Macrophages of L and P animals showed moderate and weak AT2-R staining, respectively, but the endothelium of all groups only showed weak staining. In conclusion, pulmonary hypertension induced by chronic hypoxia in newborn piglets is partially attenuated by AT1-R blockade. We suggest that AT1-R blockade might act through AT2-R and/or Mas receptors and the nitrergic system in the lungs of hypoxemic newborn piglets.

Leukotrienes are not essential for the efficacy of a heterologous vaccine against Mycobacterium tuberculosis infection

Leukotrienes are reported to be potent proinflammatory mediators that play a role in the development of several inflammatory diseases such as asthma, rheumatoid arthritis and periodontal disease. Leukotrienes have also been associated with protection against infectious diseases. However, the role of leukotrienes in Mycobacterium tuberculosis infection is not understood. To answer this question, we studied the role of leukotrienes in the protective immune response conferred by prime-boost heterologous immunization against tuberculosis. We immunized BALB/c mice (4-11/group) with subcutaneous BCG vaccine (1 x 10(5) M. bovis BCG) (prime) followed by intramuscular DNA-HSP65 vaccine (100 µg) (boost). During the 30 days following the challenge, the animals were treated by gavage daily with MK-886 (5 mg·kg-1·day-1) to inhibit leukotriene synthesis. We showed that MK-886-treated mice were more susceptible to M. tuberculosis infection by counting the number of M. tuberculosis colony-forming units in lungs. The histopathological analysis showed an impaired influx of leukocytes to the lungs of MK-886-treated mice after infection, confirming the involvement of leukotrienes in the protective immune response against experimental tuberculosis. However, prime-boost-immunized mice treated with MK-886 remained protected after challenge with M. tuberculosis, suggesting that leukotrienes are not required for the protective effect elicited by immunization. Protection against M. tuberculosis challenge achieved by prime-boost immunization in the absence of leukotrienes was accompanied by an increase in IL-17 production in the lungs of these animals, as measured by ELISA. Therefore, these data suggest that the production of IL-17 in MK-886-treated, immunized mice could contribute to the generation of a protective immune response after infection with M. tuberculosis.

Gangrena de Fournier: 10 años de experiencia / Fournier gangrene: a 10 year experience

Introducción: La gangrena de Fournier es una entidad infecciosa caracterizada por una fascitis necrotizante sinérgica rápidamente progresiva a punto de partida urinaria o colorrectal que amenaza la vida del paciente de no instaurarse un diagnóstico temprano y un tratamiento agresivo. Tiene alta prevalencia en pacientes diabéticos e inmunosuprimidos. El objetivo del trabajo es recabar la experiencia de nuestro Servicio y valorar el índice de severidad de gangrena de Fournier en un subgrupo de pacientes. Materiales y métodos: Se realizó un estudio retrospectivo descriptivo que incluyó 52 pacientes que fueron atendidos en el Servicio de Urología del Hospital Ramos Mejía en el período comprendido entre 2000-2009 con diagnóstico de gangrena de Fournier. Se evaluaron los factores predisponentes, el tiempo de evolución, el manejo quirúrgico y la mortalidad. El índice de severidad de gangrena de Fournier se realizó en el subgrupo de los últimos 20 pacientes. Todos los pacientes fueron sometidos a debridamiento quirúrgico y cobertura antibiótica. Resultados: La diabetes como factor predisponente fue identificada en 26/52 pacientes (50 por ciento). La tasa de mortalidad en nuestra serie fue del 11,5 por ciento (6/52). De los 52 pacientes incluidos, en los últimos 20 se utilizó el índice de severidad de gangrena de Fournier. De éstos, 4 presentaron un ISGF >9 puntos con 50 por ciento (2/4) de mortalidad. 49 pacientes fueron sometidos a un único y extenso debridamiento quirúrgico; los otros 3 pacientes requirieron 3 procedimientos quirúrgicos. Al 75 por ciento se les realizó derivación urinaria previo a la cirugía. Conclusión: La gangrena de Fournier es una urgencia urológica. El primer debridamiento quirúrgico debe ser el más agresivo de todos pudiendo disminuir la mortalidad y la necesidad de reintervenciones. Un índice de severidad de gangrena de Fournier >9 puntos se acompaña de una elevada tasa de mortalidad.

Introduction: Fournier gangrene is an infectious entity characterized by a necrotic fascytis or urinary or colonic origin that quickly spreads and may compromise the patient life if not timely treated. It has a high prevalence in diabetic and immunosuppressed patients.Objective: To review the experience gathered at our institution on Fournier gangrene and to evaluate the severity of this situation on a specific subgroup of patients. Material and method: Our retrospective study included 52 patients seen between the year 2000 and 2009 at the Ramos Mejía Hospital with Fournier Gangrene. Associated factors, time of evolution, surgical management and mortality were evaluated. Severity index (SI) was used on the last 20 patients. All patients underwent surgical exploration and antibiotic therapy. Results: Diabetes as predisposing factor was seen in 26 of 52 patients (50 percent). Mortality was 11.5 percent (6 patients). Out of the 20 patients in which SI was used, 4 had SI > 9 with 50 percent mortality. Of the 52 patients, 3 required more than one surgical procedure. All patients underwent urinary diversion prior to surgery. Conclusion: Fournier gangrene is a urological emergency. First surgical intervention should be very aggressive though it may decrease mortality and the need for further interventions. A SI > 9 is associated with higher mortality.

Evaluación y seguimiento de la hidronefrosis prenatal / Evaluation and follow up of prenatal hydronephrosis

Mediante la ultrasonografia prenatal se diagnostican anormalidades urinarias en el 1 por ciento de fetos. De éstas sólo persisten en el 50 por ciento de los recién nacidos (RN). Existen diferencias en la consideración del valor de corte del diámetro anteroposterior de la pelvis (DAP) fetal para definir hidronefrosis prenatal (HNPN) y numerosas controversias en el manejo de RN con ecografía normal o leve dilatación. Objetivos: Determinar inicialmente la incidencia de HN fetal en nuestra población de embarazadas y detectar la persistencia de la HNPRN en los RN, objetivando a su vez la incidencia de reflujo vesicoureteral [RVU] y obstrucción. Material y Métodos: Se revisaron las ecografías de embarazadas de segundo y tercer trimestre controladas en nuestro hospital desde noviembre de 2002 a noviembre de 2004 y ulterior seguimiento de los RN con HNPN detectadas prenatalmente. Resultados: Se analizaron 69 pacientes con 103 UR con HNPN, de los cuales 57 eran de sexo masculino y 12 de sexo femenino. La edad gestacional al momento del diagnóstico fue de X: 33,3 s (r: 22 a 40 s). El tiempo de seguimiento fue de X: 9 meses (r: 1 a 45 m). Veinticinco (24,5 por ciento) de las 103 UR fueron consideradas transitorias prenatales (TP), ya que no persistieron en etapa postnatal, mientras que 78 mostraron dilatación persistente. Sólo seis {6} de éstas, presentaron reflujo vesicoureteral. Del total de los 69 pacientes estudiados 29 (42 por ciento) manifestaron uropatías diversas distribuidas en 15 (22 por ciento) estenosis ureteropiélica (EUP), 7 (10 por ciento) riñón multiquístico (RMQ), 4 (6 por ciento) RVU y 2 (1,5 por ciento) megauréter primario no obstructivo. Conclusiones: De las 103 UR el 24 por ciento normalizaron postnatal y 76 por ciento persistieron. De éstas la EUP fue la más frecuente y el 87,5 por ciento tenía HNPN G. Las HNPN menor igual a 10 mm son poco preocupantes, dado que la mayoría mejoraron y ninguna requirió cirugía. Las HNPN de más de 10 mm persistentes...

Tiroidectomía profiláctica en niños y jóvenes con cáncer medular tiroideo hereditario: Experiencia chilena / Prophylactic thyroidectomy in children and young people with hereditary medullary thyroid carcinoma: A Chilean experience

Background: With the availability of the RET proto-oncogene genetic testing, it is possible to perform prophylactic total thyroidectomy among carriers of RET mutation. Aim: To evaluate the histological findings and the effects of the prophylactic total thyroidectomy in first-degree relatives of Chilean patients with multiple endocrine neoplasia type 2 (MEN 2) based on the Ret proto-oncogen analysis. Subjects and Methods: Nineteen patients belonging to 11 MEN 2 families underwent total thyroidectomy. Of these, 16 either with C cell hyperplasia (CCH) or microscopic medullary thyroid carcinoma (MTC) were selected for the final analysis. Results: The age at the moment of thyroidectomy ranged from 3 to 24 years (median 9.5). The most common mutation was located in codon 634 (69%) followed by codon 620 (25%). Histopathology revealed MTC in 13 patients (81%, youngest 3 years, oldest ones 19 and 24 years) and CCH in 3. A significant correlation was observed between basal preoperative serum calcitonin/tumor size (r= 0.53, P <0.05) and age/tumor size (r= 0.56, P <0.03), but not between basal preoperative serum calcitonin and age. Stimulated preoperative calcitonin levels were confounding and not useful for differentiating CCH from MTC. None of patients in whom cervical dissection was done (9/16) presented lymph node metastases, including the oldest ones. All patients but the older ones were biochemically cured after a mean of 5 years of follow-up. Conclusion: Prophylactic total thyroidectomy should be done early in life because there is an age-dependent progression from HCC to MTC. MTC often precedes biochemical detection of the disease.

Contaminación intradomiciliaria en un sector de extrema pobreza de la comuna de La Pintana / Indoor air pollution in a zone of extreme poverty at La Pintana community, Santiago

Background: Indoor pollution can be an important risk factor for human health, considering that people spend more than 60 percent of their time in their houses. Aim: To investigate indoor pollution in a zone of extreme poverty in Metropolitan Santiago. Material and methods: During 24h, carbon monoxide (CO), sulfur dioxide (SO2), respirable particulate matter (PM10), polycyclic aromatic hydrocarbons absorbed in PM5, temperature and humidity, were measured in the interior of 24 houses in La Pintana, Santiago. Results: The higher pollutant concentrations were observed during hours when heating was used, in houses that used coal (mean PM10 250 µg/m3, CO 42 ppm, SO2 192 ppb) or firewood (mean PM10 489 µg/m3, CO 57 ppm, SO2 295 ppb). In all houses, polycyclic aromatic hydrocarbons were detected and they came from the interior of the house and not from external filtered air. Coal, firewood and cigarette smoke were important sources of carcinogenic and kerosene and gas were sources of non carcinogenic polycyclic aromatic hydrocarbons. Conclusions: In the houses studied, the population was exposed to an accumulation of highly toxic pollutants, caused by a lack of ventilation. A high relative humidity also contributed to the growth of biological pollutants

Dependencia de nicotina: seguimiento a un año plazo de pacientes tratados con terapia grupal más reemplazo de nicotina / Treatment of nicotine dependence with nicotine replacement and group therapy: results of a 1 year follow up

Background: smoking is the main single avoidable cause of death in our country. Little research in the treatment of such disorder has been made. Aim: to report the results of a prospective follow up for one year of outpatients from our Smoker's Clinic at the Department of Psychiatry of the Catholic University. Patients and methods: One hundred twenty seven patients (84 male, aged 21 to 70 years old), with DSM-IV criteria for nicotine dependence, were included in a total of 18 groups. Each group received an intensive treatment program of 10 sessions with cognitive-behavioral relapse prevention techniques and nicotine replacement. Patients with active psychiatric diseases were not included in the program. Results: Eighty seven percent of subjects were abstinent at the first month and 50 percent were still abstinent after twelve months of follow up. We did not find differences in gender, age, previous psychiatric disease, number of cigarettes and breath carbon monoxide level between abstinent and non abstinent patients after 12 months of follow up. Conclusion: This intensive nicotine dependence treatment in seriously dependent patients, proved to be successful, regardless of the previous psychiatric history