Validez diagnóstica de la escala de alvarado en pacientes con dolor abdominal sugestivo de apendicitis, en un hospital de tercer nivel, del sur de bogotá

El dolor abdominal agudo es uno de los síntomas por los que un paciente asiste al servicio de urgencias de cualquier hospital, a nivel mundial, representando entre un 5 y 10% del total de consultas, constituyéndose para el médico de urgencias y especialistas interconsultados, un reto, dado que encierra varias patologías, que pueden ser o no quirúrgicas y que de no ser diagnosticadas, correcta y oportunamente, se pueden convertir en fatales, como la apendicitis, la condición patológica y quirúrgica, la que, frecuentemente, se ve enfrentado el cirujano general. El paciente, se puede presentar con signos y síntomas muy variados, que van desde un cuadro claro de apendicitis o no tener signos ni síntomas que sugieran, como diagnóstico, esta patología, por lo cual, se han desarrollado escalas que faciliten o aporten ayuda al médico para un correcto diagnóstico y posterior tratamiento. La escala de Alvarado hace parte de estas ayudas diagnósticas, siendo un método económico, no invasivo, rápido y confiable. Se evaluó por medio de este proyecto, la validez de la escala en la USS Tunal de IIII nivel, al ser uno de los hospitales más grandes y concurridos de Bogotá; para ello, se tomó una muestra de 161 pacientes y valorando cada parámetro de la escala, además, de comparar el puntaje dado por la misma y el diagnóstico histopatológico. Los resultados permiten concluir que la escala es sensible, pero no específica para el diagnóstico de apendicitis.

Acute abdominal pain is one of the symptoms which a patient attends the emergency room of any hospital worldwide, representing a 5 to 10% of those consultations; this represents for the emergency doctor and specialists interconsulted a challenge, because it contains several conditions that may or may not be surgical and not be diagnosed properly and promptly can be fatal, within these, is appendicitis, pathological and surgical condition which most often is faced the surgeon general. The patient may present with signs and varied symptoms ranging from a clear picture of appendicitis, or have no signs or symptoms suggestive as this pathology diagnosis; so scales have been developed to facilitate or provide help to the doctor for a correct diagnosis and subsequent treatment; Alvarado makes the scale of these diagnostic aids, being a non-invasive, fast and reliable economical method. Was evaluated by means of this project the validity of the scale in the USS Tunal IIII level to be one of the largest and busiest hospitals in Bogota, for this sample of 161 patients was taken Hospital and rated each parameter in addition to comparing the scores given by the same scale and histopathological diagnosis. The results show that the scale is sensitive but not specific for the diagnosis of appendicitis.

Performance quantification of clustering algorithms for false positive removal in fMRI by ROC curves

Abstract Introduction Functional magnetic resonance imaging (fMRI) is a non-invasive technique that allows the detection of specific cerebral functions in humans based on hemodynamic changes. The contrast changes are about 5%, making visual inspection impossible. Thus, statistic strategies are applied to infer which brain region is engaged in a task. However, the traditional methods like general linear model and cross-correlation utilize voxel-wise calculation, introducing a lot of false-positive data. So, in this work we tested post-processing cluster algorithms to diminish the false-positives. Methods In this study, three clustering algorithms (the hierarchical cluster, k-means and self-organizing maps) were tested and compared for false-positive removal in the post-processing of cross-correlation analyses. Results Our results showed that the hierarchical cluster presented the best performance to remove the false positives in fMRI, being 2.3 times more accurate than k-means, and 1.9 times more accurate than self-organizing maps. Conclusion The hierarchical cluster presented the best performance in false-positive removal because it uses the inconsistency coefficient threshold, while k-means and self-organizing maps utilize a priori cluster number (centroids and neurons number); thus, the hierarchical cluster avoids clustering scattered voxels, as the inconsistency coefficient threshold allows only the voxels to be clustered that are at a minimum distance to some cluster.

Influencia de factores perinatales en la pesquisa neonatal de hiperplasia adrenal congénita en Ciudad de La Habana y La Habana / Influence of perinatal factors on the neonatal screening of congenital adrenal hyperplasia in Ciudad de La Habana

Introducción: los costos económicos y psicosociales asociados con los resultados falsos positivos de la pesquisa neonatal de hiperplasia adrenal congénita son altos. Objetivos: identificar los factores perinatales que intervienen en la elevación y en el tiempo de normalización de los valores de 17 hidroxiprogesterona (17OHP), en pacientes no afectados por hiperplasia adrenal congénita. Métodos: se realizó un estudio descriptivo longitudinal retrospectivo en 1 114 pacientes procedentes de Ciudad de La Habana y La Habana, con resultados falsos positivos en la pesquisa, desde enero/2007 hasta junio/2010. Se identificaron las diferencias en la frecuencia de los factores perinatales reconocidos en este grupo con una muestra de población general, y otra integrada por enfermos de hiperplasia adrenal congénita. Resultados: de los pacientes falsos positivos, el 50,7 por ciento pertenecía al sexo masculino y 49,3 por ciento al femenino. El 54,7 por ciento nació por cesárea, y el 82 por ciento no presentó sufrimiento fetal agudo, aquellos con menor edad gestacional y peso al nacer más bajo presentaron niveles medios de 17OHP más elevados. El 68,1 por ciento normalizó la 17OHP al cumplir un mes de vida, independientemente del tipo de parto y de la presencia de sufrimiento fetal agudo; pero la edad gestacional y el peso al nacer tuvieron correlación inversa con la persistencia de su elevación. Predominó el parto eutócico en los neonatos enfermos y normales, y la cesárea en los falsos positivos. La media de la edad gestacional y del peso al nacer fue significativamente menor en los casos en el primer grupo, comparada con la de los grupos restantes. Conclusiones: la prematuridad y el bajo peso al nacer tuvieron una influencia significativa sobre la elevación y la persistencia de los valores de 17OHP, no así el tipo de parto y el sufrimiento fetal agudo(AU)

Introduction: the psychosocial and economic costs associated with the false-positive results of the neonatal screening of congenital adrenal hyperplasia are high. Objectives: to identify the perinatal factors to get involved in the rise and in the normalization time of values of 17 hydroprogesterone (17OHP) in patients not involved by a congenital adrenal hyperplasia. Methods: a retrospective, longitudinal and descriptive study was conducted in 1 114 patients from Ciudad de La Habana and La Habana with false-positive results according to screening from January, 2007 to June, 2010. Authors identified the differences in frequency of perinatal factors recognized in this group with a sample of general population, and other including congenital adrenal hyperplasia patients. Results: from the false-positive patients, the 50,7 percent was of male sex and the 49,3 percent to the female one. The 54,7 percent was born by cesarean section and the 82 percent has not acute fetal suffering, those small for the gestational age and lower birth weight had mean levels of 17OHP higher. The 68,1 percent normalized the OHP at one month of life, independently the type of labor and of the presence of acute fetal suffering but the gestational age and the birth weight had an inverse correlation with the persistence of its rise. There was predominance of eutocia labor in the sick and normal neonates and the cesarean section in the false-positive ones. The mean of gestational age and of the birth weight was significantly minor in the cases of the first group, compared with the remaining groups. Conclusions: the prematurity and the low birth weight had a significant influence on the rise and the persistence of values of 17OHP, but not the type of labor and the acute fetal suffering(AU)

Common causes of false positive F18 FDG PET/CT scans in oncology

PET/CT is a common imaging modality used in the evaluation of oncology patients. While being extremely sensitive to identifying sights of malignancy F18FDG is very non-specific. We attempted to provide a brief review of some of the more common processes that a nuclear radiology physician may encounter in daily clinical practice that could result in a false positive diagnosis with F18FDG PET/CT. A fundamental understanding of the limitations of this technology by the interpreting physician is necessary to avoid making inaccurate diagnosis and potentially limiting important treatments for our patients.

PET/CT é uma modalidade de imagem usada para avaliação de pacientes oncológicos. Embora seja extremamente sensível para identificar sinais de malignidade, o F18FDG não é ainda muito específico. Nós buscamos mostrar uma breve revisão de alguns dos processos mais comuns que um médico nuclear pode encontrar na prática clínica diária que poderia resultar em um diagnóstico falso positivo com a F18FDG PET/CT. Uma melhor compreensão das limitações dessa tecnologia é necessária para que a interpretação pelo médico não possibiite diagnósticos imprecisos, que potencialmente podem limitar os tratamentos dos pacientes.