Exactitud diagnóstica de la tomografía computarizada en la estadificación del cáncer de colon / Diagnostic accuracy of computed tomography in colon cancer staging

Resumen Introducción: Una terapia emergente para el cáncer de colon es la neoadyuvancia, en casos seleccionados. Dicha selección se basa en el análisis preoperatorio de imágenes mediante tomografía computada. Objetivo: Nuestro objetivo es determinar la exactitud diagnóstica del examen para estadificar el cáncer de colon y su correlación entre radiólogos expertos. Materiales y Método: Estudio de exactitud diagnóstica. Previo cálculo muestral se seleccionaron aleatoriamente 47 pacientes con adenocarcinoma colónico resecado con intención curativa e imágenes hasta 60 días previo cirugía. Se evaluó profundidad de invasión tumoral e invasión linfonodal por 2 radiólogos expertos y ciegos entre sí. Las diferencias fueron auditadas por un tercer radiólogo experto. Se compararon resultados con la biopsia, calculando la sensibilidad, especificidad, valor predictivo negativo, valor predictivo positivo y exactitud diagnóstica del examen. Se calculó la concordancia entre radiólogos mediante el índice de kappa. Resultados: La exactitud para diferenciar tumores T3-T4 de T1-T2 fue del 89,4%. En cambio, la capacidad para diferenciar tumores T4 de los T3 fue de un 65,9%. La exactitud para determinar un N (+) fue de un 66%. La concordancia entre radiólogos fue de 0,929 para identificar tumores T1-2, de 0,602 para T3, de 0,584 para T4. Para determinar un N (+), la concordancia fue de 0,521. Conclusión: La exactitud diagnóstica de la tomografía computada en cáncer de colon es adecuada para distinguir tumores avanzados. Sin embargo, su capacidad para discriminar entre T3 y T4, los N (+) y la baja concordancia entre radiólogos, sugiere la necesidad de buscar técnicas imagenológicas complementarias.

Introduction: Neoadjuvant therapy is an emerging treatment for selected cases of colon cancer. The decision is based on the analysis of preoperative images taken by computed tomography. However, its ability to discriminate those who could benefit from this therapy is unknown. Aim: Our objective is to determine the diagnostic accuracy of computed tomography to evaluate the colon cancer stage and its correlation among expert radiologists. Materials and Method: Diagnostic accuracy study. After sample size calculation, we randomly selected 47 patients who underwent a colonic adenocarcinoma resection with curative intent and had available images up to 60 days after surgery. The depth of tumor and lymph nodal invasion were evaluated by two expert radiologists, blinded to each other. The differences between radiologists were audited by a third one. The results were correlated with biopsy as the gold standard. We calculated sensitivity, specificity, negative predictive value, positive predictive value, and diagnostic accuracy of computed tomography. The agreement between radiologists was calculated using the kappa index. Results: The accuracy to differentiate T3-T4 tumors from T1-T2 was 89.4%. In contrast, ability to differentiate T4 tumors from T3 tumors was 65.9%. The accuracy to determine an N (+) was 66%. Agreement between radiologists was 0.929 to identify T1-2, 0.602 for T3, 0.584 for T4 tumors. To determine an N (+), the concordance was 0.521. Conclusion: Diagnostic computed tomography accuracy in colon cancer is adequate to differentiate advanced tumors. However, its ability to discriminate between T3 and T4, N (+) and the low agreement between radiologists suggests the need for complementary imaging techniques.

Effect of a high Na+ diet on cell volume and Na(+)-stimulated ATPase activities of rat kidney membranes.

Proximal tubular cells from kidneys of male rats chronically fed with an isotonic NaCl solution, show a volume increase which is dependent on the length of the treatment with NaCl, when compared with control rats. Parallel to the cell volume increase, there is an increase of the ouabain-insensitive Na-ATPase activity, whereas the ouabain-sensitive Na,K-ATPase activity remains unchanged. These results establish a clear relationship between a chronic Na-diet, kidney cell volume and Na-ATPase activity.

Evaluación de habilidades transversales de comunicación y colaboración a través de un examen clínico objetivo estructurado de radiología de urgencias para residentes de un programa universitario de especialidad en radiología / Assessment of generic skills in communication and collaboration through an objective structured clinical examination in emergency radiology in a university residency program in Chile

Introducción: La Radiología de Urgencias es una unidad de aprendizaje longitudinal a toda la residencia. En ella los residentes se enfrentan a patología de urgencia en distintas modalidades de imagen. Además del dominio cognitivo, los residentes deben desarrollar habilidades de comunicación y colaboración que les permitan enfrentar adecuadamente los turnos de residencia. Previo a incorporarse a los turnos nocturnos, los residentes deben aprobar un Examen Clínico Objetivo Estructurado (ECOE). Propósito: Evaluar competencias de comunicación y colaboración a través de estaciones de ECOE de Radiología de Urgencias aplicado a residentes de 2º año de residencia. Metodología: Se seleccionaron objetivos específicos a evaluar para las competencias de comunicación y colaboración y contenidos de Radiología Abdominal, Osteoarticular y Pediátrica para diseñar tres estaciones de ECOE, las cuales fueron incorporadas en el instrumento de evaluación aplicado el año 2017. Se calcularon porcentajes de logro por estación y tipo de pauta de evaluación. Para evaluar la implementación de las estaciones, se diseñó y aplicó una encuesta de percepción a los residentes. Resultados: Se diseñaron tres estaciones, dos para el rol Comunicador y una para el rol Colaborador. La validez de contenido se aseguró a través de un panel de expertos. Los porcentajes de logro global en las estaciones fluctuaron entre 74,7% y 95,6%. Las estaciones fueron bien evaluadas por parte de los residentes, quienes valoraron la incorporación de competencias diferentes al dominio cognitivo en el instrumento de evaluación. Conclusión: El ECOE permite certificar habilidades transversales como comunicación y colaboración de manera apropiada

Introduction: Emergency radiology (ER) is taught and learned throughout the entire residency. Trainees are exposed to different subspecialties ER cases and through varied imaging techniques. In addition to the "medical expert" domain, residents must develop communication and collaboration skills that will help them during their call schedule. Before they can take night-call, radiology residents must pass an Objective Structured Clinical Examination (OSCE). Purpose: To evaluate communication and collaboration competencies on an ER-OSCE applied to second-year radiology residents. Methods: Specific learning objectives were defined to evaluate communication and collaboration skills in abdominal, musculoskeletal and pediatric ER. Three OSCE stations were designed for this purpose and added to the evaluation instrument in 2017. On each station, resident performance was assessed with a specific template and percentage of goal achievement was calculated. Trainee´s opinion of this new modality was obtained through a perception survey. Results: Three stations were designed, two for the communicator role and one for the collaborator competency. Validity of content confirmed through an expert panel. Percentages of goal achievement on each station varied between 74,7% and 96,6. The new stations were positively evaluated by residents, which valued that competencies other than "medical expert" were being assessed. Conclusion: ER-OSCE allows the appropriate assessment of generic competencies such as communication and collaboration in radiology.

Presencia de marcadores de las vías de activación de los macrófagos en periodontitis crónica / Presence of markers of activation pathways of macrophages in chronic periodontitis

La periodontitis crónica es una patología infecciosa, causada por un complejo de especies bacterianas, que afecta principalmente los tejidos de inserción de los dientes. La respuesta inmune-inflamatoria producida se caracteriza por la presencia de un infiltrado inflamatorio, en el cual los macrófagos representan entre 5 al 30 por ciento. Es sabido que los macrófagos se activan mediante dos vías: Clásica y Alterna, caracterizadas por la presencia de marcadores indirectos: IFN-y e IL-6 para la vía clásica e IL-4 para la vía alterna, ampliamente abordados. Recientemente, se ha descrito a la subunidad A del factor XIII de la coagulación (FXIII-A) como un buen marcador de la vía alterna. El objetivo de este estudio consiste en determinar la presencia de IFN-y, IL-6, FXIII-A e IL-4 como marcadores de las vías de activación de los macrófagos, en pacientes con periodontitis crónica. Para tal efecto, se realizó inmunohistoquímica y Western-Blot para los cuatro marcadores junto a CD-68, marcador de macrófagos, en 18 biopsias de tejido periodontal sano y 18 con periodontitis crónica. Se detectó la presencia de IFN-y, IL-6, IL-4 y FXIII-A junto a CD68+, en todas las muestras de pacientes sanos y con periodontitis. Los resultados obtenidos sugieren que al estar presente IFN-y, IL-6, IL-4 y FXIII-A, los macrófagos se activarían a través de ambas vías, lo cual, produciría una respuesta tanto proinflamatoria (Th1) como antinflamatoria (Th2). Son necesarios más estudios para determinar si existe una vía preferencial de activación.

Periodontitis is a chronic infectious disease caused by a bacterial species complex, which affects mainly the insertion tissues of the teeth. The immune-inflammatory response produced is characterized by an inflammatory infiltrate in which macrophages represent between 5 to 30 percent. It is known and has been widely discussed that macrophages are activated in two ways: Classical and Alterna, characterized by the presence of indirect markers: IFN-y and IL-6 for the classical pathway and IL-4 for the alternative pathway. Recently the subunit A of the clotting factor XIII (FXIII-A) has been described as a good marker of the alternative pathway. The objective of this study is to determine the presence of IFN-y, IL-6, IL-4 and FXIII-A as markers of the macrophage activation pathways in patients with chronic periodontitis. To this end, we performed immunohistochemistry and Western blot for the four markers with CD68 macrophage marker, in 18 healthy periodontal tissue biopsies and 18 with chronic periodontitis. We detected the presence of IFN-y, IL-6, IL-4 and FXIII-A with CD68 +, in all samples of healthy patients and periodontitis. The results suggest that when present, IFN-y, IL-6, IL-4 and FXIII-A, activate macrophages through both routes, which would produce a proinflammatory response (Th1) as antiinflammatory (Th2). Further studies are necessary to determine whether there is a preferential pathway activation.

Carcinoma papilar seroso primario del peritoneo: reporte de un caso / Peritoneum primary papillary serous carcinoma: case report

Primary serous papillary carcinoma of the peritoneum is a rare neoplasm. It is characterized by peritoneal carcinomatosis, asertes and identical histology to ovarian serous papillary carcinoma, but wrth unaffected or only superficially affected ovaries. The main differential diagnoses are secondary peritoneal carcinomatosis, peritoneal tuberculosis, malignant peritoneal mesothelioma and peritoneal lymphomatosis. The computer tomography and CA 125 are the main diagnostic tools, but the histology is essential. In this report, we present a case of a 57 years old woman with this neoplasm, metastazised to colon, uterus and ovaries. She was treated with optimal cytoreduction and chemotherapy.

El carcinoma papilar seroso primario del peritoneo es una neoplasia rara. Se caracteriza por carcinomatosis peritoneal, ascitis y una histología idéntica al carcinoma seroso papilar de ovario, pero sin comprometerlo o afectándolo sólo superficialmente. Se debe plantear como principales diagnósticos diferenciales la carcinomatosis peritoneal secundaria, la tuberculosis peritoneal, el mesotelioma peritoneal maligno y la linfomatosis peritoneal. La tomografía computada y el CA 125 representan las principales herramientas diagnósticas, sin embargo, la histología resulta imprescindible. En el presente artículo, presentamos un caso de una mujer de 57 años con esta neoplasia en que se demostró además compromiso de colon, útero y anexos. Se manejó con citoreducción óptima y quimioterapia posterior.

Presencia de linfocitos T reguladores en periodontitis crónica / Presence of T regulatory cells in chronic periodontitis

La enfermedad periodontal requiere de un hospedero susceptible para su desarrollo y progresión. Dentro de las características del hospedero se encuentra la respuesta T reguladora, que otorga tolerancia frente a antígenos propios, participa durante las enfermedades infecciosas limitando el daño tisular, sin disminuir la respuesta antibacteriana. El presente estudio tiene por objetivo determinar la presencia, reclutamiento y función de Tregs en pacientes con periodontitis crónica. En 10 biopsias de tejido periodontal sano y con periodontits crónica se realizó inmunohistoquímica para marcadores (CD4, CD25, Foxp3), quimioquinas (CCL17, CCL22) y citoquinas (TGF-B, IL-10) de Tregs. Además de Western-Blot para detectar las citoquinas. Los resultados obtenidos sugieren una posible asociación entre células Tregs y la infección periodontal, ya que se confirma su reclutamiento y presencia. Sin embargo, son necesarios más estudios del posible desbalance con su contraparte pro-inflamatoria Th17, que expliquen en parte la compleja etiopatogenia de la enfermedad periodontal.

Periodontal disease requires a susceptible host to initiation, development and progression. T regulatory response is one of these inmunoregulatory characteristics of the susceptible host, which provide tolerance, tissular protection during infection without impairing the control of periodontopathogens. The aim of this study is to determinate the presence, homing and function of T regulatory cells (Tregs) in patients with chronic periodontitis. Ten biopsies were taken from pockets, the presence of Tregs markers (CD4, CD25, Foxp3), chemokines (CCL17, CCL22) and cytokines (TGF-p, IL-10) were determinate by immunohistochemistry. Cytokines also were detected with Western-Blot. Our results suggest a possible association between Tregs and periodontal infection, confirming homing and presence of Tregs. However, further studies are required to determine the possible imbalance with pro-inflammatory part Th17, that might explain the complex etiopathogenesis of periodontal disease.

[Some considerations about hepatitus C virus]. / Algunas consideraciones sobre el virus de la hepatitis C.

PIP: Hepatitis C refers to the portion of non-A, non-B hepatitis that is parenterally transmitted. No formal classification of the virus has yet been achieved, but it is known to be heterogeneous, a trait with implications for both antiviral therapy and vaccine development. Hepatitis C virus has a nearly uniform distribution around the world. The highest infection rates are found in patients with non-A, non-B hepatitis associated with transfusion, hemophiliacs receiving coagulation factors, intravenous drug users, and renal dialysis patients. Screening for hepatitis C, even using third generation ELISA tests, has not completely eliminated risk of transmission during blood transfusions. Nonpercutaneous routes of transmission have been poorly defined. There is evidence that hepatitis C virus is sexually transmitted, but less efficiently than hepatitis B or HIV. Hepatitis C infections have been found in newborns and in children receiving transfusions, undergoing renal dialysis, or hospitalized. The high percentage of hepatitis C in persons with no history of parenteral exposure has stimulated search for nonparenteral forms of transmission, especially vertical transmission. The resulting data have been contradictory. Results of recent studies using polymerase chain reaction appear to indicate that perinatal transmission occurs, but an elevated viral load of hepatitis C is required to produce infection. The majority of hepatitis C cases are asymptomatic. Normal serum aminotransferase levels may mask persistent infection and progression to cirrhosis. More serious consequences of chronic infection may include persistent acute or chronic hepatitis, with cirrhosis developing in 20-30% of cases, and hepatocellular carcinoma. The most effective treatment of chronic infection, alpha interferon, is associated with a relapse rate of 80-90%. Prevention is thus the most effective intervention to combat hepatitis C.^ieng

[Changes in the pain produced by the peripheral venous injection of propofol when it is combined with lidocaine or fentanyl]. / Modificación del dolor producido con la inyección venosa periférica de Propofol al combinarlo con Lidocaína o Fentanyl.

The author studied the use of intravenous Propofol for the relief of pain. He demonstrated that Propofol and 10 mg of Lidocaine intravenously decreased moderate or severe pain from 31.6% to 9% and that increasing the dose of Lidocaine did not significantly decrease the pain further. Fentanyl did not produce a statistically significant further diminution of the pain from the level of relief obtained with Propofol.

[Cholecystectomy by video laparoscopy: 100 consecutive cases]. / Colecistectomía por video laparoscopia. 100 casos consecutivos.

The cholecystectomy by video-laparoscopy has made a revolution in biliary surgery. We present the first 100 cases operated with this technique in acute and chronic cholecystitis. Eighty five percent (85%) with admissions of less than 24 hours, a low morbidity and convalescence period of less than seven days. To perform this procedure is necessary basic training in surgery and endoscopy, the appropriate equipment and team of surgeons.

[Cholecystectomy by video laparoscopy in acute cholecystitis: report of 25 cases]. / Colecistectomía por video laparoscopia en colecistitis aguda. Reporte de 25 casos.

The cholecystectomy by video laparoscopy has made a big revolution in biliary surgery during de last three or four years. We present the first 25 cases with acute cholecystitis operated on by this technique with very low morbidity a convalescence period and hospitalization time inferior to the one expected for open cholecystectomy and a conversion to open laparotomy in a relatively low percentage of the cases. In order to perform this procedures a basic training in surgery and laparoscopy is necessary groups of surgeons that work coordinated with adequate instrumentation as well as experience in laparoscopic cholecystectomy in non acute cases is always necessary.

Na(+)-ATPase activity, cell ion and water contents of kidney cortex slices from rats on a high Na+ diet.

Rats chronically fed for 15 months with an isotonic NaCl solution show a volume increase of their kidney proximal tubular cells as well as of the ouabain-insensitive, Na-stimulated ATPase activity of basolateral plasma membranes from these cells. If the experimental rats are changed to tap water after 15 months of the high sodium diet, the results are partially reversed. Thus, the cell volume and the Na-ATPase activity of their basolateral plasma membranes decrease, reaching values closer to those of control rats. There is more Na+ and Cl- in the cells from rats under the high Na(+)-diet than in the cells from control rats. On the other hand, when the rats on the high sodium diet are changed to control conditions (drinking tap water), their Na+ and Cl- contents decrease, approaching control values. It is proposed that the Na-ATPase activity is modulated "in vivo" by the cell volume.

[Acute cholecystitis: is it a laparoscopic procedure?]. / Colecistitis aguda: es un procedimiento laparoscópico?

One-hundred and twenty-seven consecutive patients with acute cholecystitis were operated using laparoscopic technique. Average Surgical operating time was 113 minutes with an average of 127 minutes if operative cholangiogram was performed and 96 minutes when cholangiogram was not done. Technical difficulties related to gallbladder edema and hyperemia was seen in all cases (100%), also poor exposure and difficulty in grasping the gallbladder in 87%. The most common post operative complication was the wound infection of the entry trocar port, mainly at the umbilicus. One patient with gangrenous cholecystitis and multiple organ failure died after endoscopic attempt and converted to open technique. The total number conversions was 3%. In 28% of the patients a ERCP was done with ten positive for common duct stones. Operative cholangiogram was attempted in all cases with 83% success rate and 5% where positive for common duct stones. In cases where ERCP was done postoperatively for suspicious stones, seven cases were positive. Hospital stay averaged 1.6 days. Acute cholecystitis does not contraindicate laparoscopic technique and chances of having concomitant common duct stone is 16%, for that reason radiologic studies are mandatory.

Infectiousness of Mycobacterium tuberculosis in HIV-1-infected patients with tuberculosis: a prospective study.

BACKGROUND: Previous studies concerning the relative infectiousness of HIV-1-positive individuals with pulmonary tuberculosis have produced conflicting results. Thus, we assessed the effect of HIV-1 on the infectiousness of Mycobacterium tuberculosis in a prospective study. METHODS: We organised in Santo Domingo, Dominican Republic, a cohort study of household contacts of HIV-1-positive and HIV-1-negative individuals with newly diagnosed pulmonary tuberculosis. Household contacts were assessed at their houses at baseline and followed up for 14 months for evidence of M tuberculosis infection and tuberculosis with a multi-step tuberculin skin test, anergy skin test, physical examinations, chest radiographs, and sputum smears. FINDINGS: Tuberculin induration of 5 mm or greater was seen in 153 (61%) of 252 household contacts of HIV-1-positive index cases and in 418 (76%) of 551 household contacts of HIV-1-negative index cases (odds ratio 0.49 [95% CI 0.35-0.67], p=0.00001). In multivariate logistic-regression analysis after allowance for between-household variation in tuberculin response, HIV-1 infection of the index case remained inversely associated with the tuberculin response of the household contacts (0.52 [0.29-0.93], p=0.02). When the analysis was restricted to household contacts aged between 2 years and 15 years the adjusted association remained significant (0.37 [0.14-0.98], p=0.04). Among household contacts who had a negative tuberculin skin test at baseline, conversion to tuberculin skin test positivity was less frequent among household contacts of HIV-1-positive index cases (cut-off > or =5 mm: 32/131 [24%] vs 71/204 [35%], p=0.05; cut-off > or =10 mm: 23/153 [15%] vs 55/245 [22%], p=0.07). INTERPRETATION: These data suggest that HIV-1-positive individuals with tuberculosis are less likely than HIV-1-negative individuals with tuberculosis to transmit M tuberculosis to their close contacts. No changes in the current policy regarding tuberculosis contact tracing are needed in the presence of HIV-1.