[Reduction in Helicobacter pylori infection among patients referred for upper gastrointestinal endoscopy in Santiago, Chile, between 2010-2020]. / Reducción de la infección por Helicobacter pylori en pacientes derivados a endoscopia digestiva alta en Santiago de Chile entre 2010-2020.

Latin America presents a high prevalence of Helicobacter pylori(Hp) infection. Between1996-2003, the prevalence in Santiago, Chile, was 70%; recent studies indicate a decreasein this infection. Updating the frequency of Hp is crucial due to its associated health impact. OBJECTIVE: Our objective was to describe the trend in Hp infection in patients undergoingambulatory esophagogastroduodenoscopy (EGD) in a Chilean population. MATERIALS AND METHODS: A retrospective observational study was conducted on patients over 18 years old who attended a first EGD with a rapid urease test between 2010-2020. Time trendswere described through time series analysis. A Poisson model was constructed to estimatethe risk of infection, adjusted for age and gender. RESULTS: 11,355 patients were included[66.9% females; mean age 52 years; Hp 41.6%]. Male gender presented a higher frequencyof Hp infection [RR 1.13; (95% CI: 1.08-1.18)].Hp frequency infection decreased significantlyfrom 45.1% in 2010 to 29% in 2020, with a 36% lower probability of Hp infection in 2020 compared to 2010 [RR 0.64;(95% CI: 0.55-0.74)]. A progressive decline in Hp infectiontrend was projected, reaching values close to 25% by year 2025. CONCLUSION: A significantreduction in Hpinfection was observed between 2010-2020. This decrease could be explained by the implementation of public health policies in the last decade associated with socio-sanitary changes.

Clinical features and prognosis of malignant small bowel tumors: Experience from a university hospital in Chile.

BACKGROUND: Small bowel tumors (SBT) are infrequent and represent a small proportion of digestive neoplasms. There is scarce information about SBT in Latin America. AIM: To describe the epidemiology, clinical characteristics, diagnostic methods, and survival of malignant SBTs. METHODS: Retrospective observational study of adult patients with histopathological diagnosis of SBT between 2007 and 2021 in a university hospital in Chile. RESULTS: A total of 104 patients [51.9% men; mean age 57 years] with SBT. Histological type: neuroendocrine tumor (NET) (43.7%, n=38), gastrointestinal stromal tumors (GIST) (21.8%, n=19), lymphoma (17.2%, n=15) and adenocarcinoma (AC) (11.5%, n=10). GIST was more frequent in duodenum (50%; n=12) and NET in the ileum (65.8%; n=25). Metastasis was observed in 17 cases, most commonly from colon and melanoma. Nausea and vomiting were significantly more often observed in AC (p=0.035), as well as gastrointestinal bleeding in GIST (p=0.007). The most common diagnostic tools were CT and CT enteroclysis with an elevated diagnostic yield (86% and 94% respectively). The 5-year survival of GIST, NET, lymphoma and AC were 94.7% (95%CI: 68.1-99.2), 82.2% (95%CI: 57.6-93.3), 40.0% (95%CI: 16.5-82.8) and 25.9% (95%CI: 4.5-55.7%), respectively. NET (HR 6.1; 95%CI: 2.1-17.2) and GIST (HR 24.4; 95%CI: 3.0-19.8) were independently associated with higher survival compared to AC, adjusted for age and sex. CONCLUSIONS: Malignant SBT are rare conditions and NETs are the most common histological subtype. Clinical presentation at diagnosis, location or complications may suggest a more probable diagnosis. GIST and NET are associated with better survival compared to other malignant subtypes.

Implementation of the updated Sydney system biopsy protocol improves the diagnostic yield of gastric preneoplastic conditions: Results from a real-world study.

BACKGROUND: The updated Sydney system biopsy protocol (USSBP) standardizes the sampling of gastric biopsies for the detection of preneoplastic conditions (e.g., gastric intestinal metaplasia [GIM]), but the real-world diagnostic yield is not well-described. AIM: To determine whether regular application of USSBP is associated with higher detection of chronic atrophic gastritis (CAG), GIM and autoimmune gastritis (AIG). METHODS: We performed a real-world retrospective study at an academic urban tertiary hospital in Chile. We manually reviewed medical records from consecutive patients undergoing esophagogastroduodenoscopy (EGD) from January to December 2017. Seven endoscopists who performed EGDs were categorized into two groups (USSBP 'regular' and USSBP 'infrequent') based on USSBP adherence, using minimum 20% adherence as the prespecified threshold. Multivariable logistic regression models were used to estimate the odds ratios (aOR) and 95% confidence intervals (CI) for the association between endoscopist groups and the likelihood of diagnosing CAG, GIM or AIG. RESULTS: 1206 patients were included in the study (mean age: 58.5; 65.3% female). The USSBP regular group demonstrated a higher likelihood of detecting CAG (20% vs. 5.3%; aOR 4.03, 95%CI: 2.69-6.03), GIM (12.2% vs. 3.4%; aOR 3.91, 95%CI: 2.39-6.42) and AIG (2.9% vs. 0.8%; aOR 6.52, 95%CI: 1.87-22.74) compared to infrequent group. Detection of advanced-stage CAG (Operative Link for Gastritis Assessment stage III/IV) was significantly higher in the USSBP regular vs. infrequent group (aOR 5.84, 95%CI: 2.23-15.31). CONCLUSIONS: Routine adherence to USSBP increases the detection rates of preneoplastic conditions, including CAG, GIM and AIG. Standardized implementation of USSBP should be considered in high gastric cancer risk populations.

Portafolio en pregrado de Medicina: impacto educacional a 10 años de su implementación / Educational impact after 10 years of implementation of a portfolio for undergraduate medical students

Background: A portfolio is a compilation of academic work that demonstrates student's knowledge, reflection and critical thinking. Aim: To describe the development and implementation of an undergraduate portfolio in the School of Medicine at the Pontificia Universidad Católica de Chile, its temporal evolution and its educational impact after 10 years of experience. Material and Methods: The development and implementation of a portfolio for 4th-year undergraduate medical student was analyzed. Its design, teaching and learning methodologies, results and perceptions of students and teachers were assessed. The educational impact was measured using Kirkpatrick's levels. Results: A total of 1,320 students participated between 2007 and 2017, supported by six teachers and 190 assistant-students. The portfolio included clinical cases, narrative medicine, palliative care and evidence-based medicine (EBM). The overall student's perception was positive, highlighting the development of critical analysis, clinical reasoning and professionalism. The delivery of feedback and learning assessment, allowed students to obtain excellent grades. There were only two cases of plagiarism reported. Fifteen EBM articles and two books with 52 narrative medicine essays were published. The greatest organizational impact of this teaching innovation, was that it evolved to become an established and continuous assessment instrument in 10 consecutive years. Conclusions: This portfolio is a project with a high educational impact, with a favorable perception by students and tutors, excellent results related to grades, stimulating both scientific writing and reflective practice.

Prioritization for liver transplantation using the MELD score in Chile: Inequities generated by MELD exceptions.: A collaboration between the Chilean Liver Transplant Programs, the Public Health Institute and the National Transplant Coordinator.

INTRODUCTION AND AIM: The MELD score has been established as an efficient and rigorous prioritization system for liver transplant (LT). Our study aimed to evaluate the effectiveness of the MELD score as a system for prioritization for LT, in terms of decreasing the dropout rate in the waiting list and maintaining an adequate survival post-LT in Chile. MATERIALS AND METHODS: We analyzed the Chilean Public Health Institute liver transplant registry of candidates listed from October 15th 2011 to December 31st 2014. We included adult candidates (>15 years old) listed for elective cadaveric LT with a MELD score of 15 or higher. Statistical analysis included survival curves (Kaplan-Meier), log-rank statistics and multivariate logistic regression. RESULTS: 420 candidates were analyzed. Mean age was 53.6±11.8 years, and 244 were men (58%). Causes of LT included: Liver cirrhosis without exceptions (HC) 177 (66.4%); hepatocellular carcinoma (HCC) 111 (26.4%); cirrhosis with non-HCC exceptions 102 (24.3%) and non-cirrhotic candidates 30 (7.2%). LT rate was 43.2%. The dropout rate was 37.6% at 1-year. Even though the LT rate was higher, the annual dropout rate was significantly higher in cirrhotic candidates (without exceptions) compared with cirrhotics with HCC, and non-HCC exceptions plus non-cirrhotic candidates (47.9%; 37.2% and 24.2%, respectively, with p=0.004). Post-LT survival was 84% per year, with no significant differences between the three groups (p=0.95). CONCLUSION: Prioritization for LT using the MELD score system has not decreased the dropout rate in Chile (persistent low donor's rate). Exceptions generate inequities in dropout rate, disadvantaging patients without exceptions.

Más allá de las moléculas Lo que los clínicos desconocen: acortando brechas / Filling the gap: Beyond molecules What clinicians ignore

Para acortar la brecha entre lo molecular y la clínica, el personal de atención médica debe tener un conocimiento básico de los mecanismos moleculares que gobiernan la identidad celular, mediante la activación selectiva de genes. La expresión diferencial de genes permite a las células sintetizar las proteínas requeridas para cumplir con sus funciones biológicas, y ello posibilita a las células responder a estímulos internos y externos. Para esto se debe tener primero acceso a los genes que codifican las proteínas, determinando el fenotipo celular. Modificaciones en la estructura de la cromatina permiten a la maquinaria transcripcional tener acceso a secuencias de ADN. El ADN es transcripto en ARNm, que sufre diversas modificaciones antes de salir del núcleo para ser traducido en una proteína en el citoplasma. Cualquier desregulación en alguno de los procesos asociados se presenta como una patología. A inicios del siglo XXI se reportó la secuenciación del genoma humano, y sorprendentemente uno de los principales hallazgos fue que solo un 2% de la secuencia codifica para proteínas, lo cual dejó un interrogante sobre cómo funcionan y se regulan los procesos genéticos que llevan a la identidad celular. Desde entonces las investigaciones han permitido utilizar los principios que rigen estos procesos para ampliar el conocimiento de los mecanismos asociados a enfermedades. Gracias a estos avances, se ha buscado determinar aplicaciones clínicas dirigidas a los procesos involucrados en la expresión génica diferencial, lograr una mejor comprensión sobre los procesos patológicos de la enfermedad y desarrollar herramientas diagnósticas.

To narrow the gap between the bench and the clinic, healthcare personnel should have a basic understanding of molecular mechanisms ruling cell identity, since it establishes the key differences between health and disease states. Differential gene expression allows for protein synthesis required for the cell's biological function. In this process genes are selected from the entire genome to meet the cell's biological functioning and respond to internal and external stimuli. To this end, first the chromatin must be remodeled for the transcriptional machinery to gain access to DNA sequences coding for particular genes. DNA can then be transcribed into mRNA, followed by different processes leading to mature mRNA leaving the nucleus for protein synthesis in the cytoplasm. Any dysregulation in these processes results in disease. In the beginning of this millennium the human genome project sequenced the whole genome. Surprisingly, one of the main findings was only 2% of the genome represented protein coding sequences, which raised the question about the remainder of the genome and cell identity. Based on principles derived from the human genome project many investigations have shed light on mechanisms associated with disease. Thanks to advancements in differential gene expression, researchers are seeking for a better understanding in pathological processes associated with disease and the development of diagnostic tools.

Serum cytokeratin-18 fragment levels as noninvasive marker of nonalcoholic steatohepatitis in the chilean population. / Fragmento sérico de citoqueratina-18 como marcador no invasivo de esteatohepatitis no alcohólica en población chilena.

Nonalcoholic steatohepatitis (NASH) is the most aggressive form of nonalcoholic fatty liver disease (NAFLD) and involves the risk of progression to more advanced stages of liver disease. Non-invasive methods are needed to identify patients with NASH. OBJECTIVE: To evaluate the diagnostic performance of the determination of serum levels of cytokeratin-18 (CK-18) as a non-invasive marker of NASH in the Chilean population. METHODS: Serum CK-18 levels were determined in a group of 41 patients with biopsy-proven NAFLD. NASH diagnosis was based on Brunt's criteria (histological parameters and ballooning), and the NAFLD activity score (NAS) and the presence of fibrosis were determined. The correlation between the NAFLD activity score (NAS) and CK-18 was evaluated with Spearman's rank correlation coefficient. A ROC curve was produced to assess the diagnostic value of CK-18 for NASH. The NAFLD fibrosis score (NFS) (to predict fibrosis and NASH) was compared to CK-18 with simple linear regression. Data were expressed in median [25th-75th percentile] and evaluated with the Wilcoxon rank test. RESULTS: The mean age of the study group (23% male) was 50.4±11.1 years. 34.2% were diagnosed with NASH (NAS≥5). CK-18 levels were significantly higher in patients with NASH versus those without NASH (183.6 IU/l [97.4 to 734.4] vs. 117.2 IU/l [83.8 to 954.8], p= 0.016). CK-18 levels were a good predictor of NASH on biopsy with an area under the curve (AUC) of 0.732 (95% CI, 0.572 to 0.897). A CK-18 cut-off of 130.5 IU/l had a sensitivity of 92.9%, specificity of 63%, positive predictive value of 56.5% and negative predictive value of 94.4%, and was able to correctly classify 73.2% of patients with NASH. NFS identified advanced liver fibrosis (AUC 0.739, 95% CI, 0.56-0.91), but was of limited value to identify NASH (AUC 0.413, 95% CI, 0.21-0.61). CONCLUSION: CK-18 is a good non-invasive marker for NASH. Although NFS was found to be an accurate marker of advanced liver fibrosis, it was not of value to identify NASH. In patients with NAFLD, CK-18 and NFS could be useful in predicting NASH and liver fibrosis, respectively.

Burnout en médicos residentes de especialidades y subespecialidades: estudio de prevalencia y variables asociadas en un centro universitario / Burnout in resident doctors of specialties and subspecialties: study of prevalence and associated variables in a university center

Introducción: El burnout es un síndrome caracterizado por agotamiento emocional, despersonalización y bajo sentido de logro personal. Los médicos residentes de especialidad y subespecialidad constituyen una población de riesgo por la alta carga laboral y la interferencia con su vida personal. Nuestro objetivo fue evaluar la prevalencia de burnout y su asociación con variables sociodemográficas, en residentes de especialidad y subespecialidad de la Pontificia Universidad Católica de Chile (PUC). Métodos: Se realizó una encuesta electrónica a los residentes de especialidad y subespecialidad de la PUC, que incluyó el "Inventario de Burnout de Maslach" (22 preguntas divididas en 3 dimensiones). Se sumaron los puntos de cada dimensión y se clasificó a los residentes en riesgo de burnout al presentar altos índices de agotamiento emocional y/o despersonalización. El análisis estadístico incluyó un análisis univariado y multivariado. Resultados: 415 encuestas fueron contestadas (tasa de respuesta 86 por ciento). El 38,3 por ciento de los residentes cumplió criterios de burnout, con un 41,9 por ciento en residentes de especialidad y 24,1por ciento en residentes de subespecialidad. En el análisis por subgrupos, la mayor prevalencia se encontró en especialidades quirúrgicas (55,3por ciento). Los residentes extranjeros, los programas de especialidad (comparados con subespecialidad) y los programas de especialidades quirúrgicas se asociaron de manera independiente a burnout (OR 3,8 IC95 por ciento 1,4-10,5, p=0,01; OR 2,3 IC95 por ciento 1,3-4,1, p<0,01 y OR 1,7 IC95 por ciento 1,1-2,7; p=0,02, respectivamente). La carga laboral horaria no se asoció de manera independiente a burnout (p=0,19). Conclusión: Los residentes de especialidad y subespecialidad presentan una alta prevalencia de burnout. Adicionalmente, ser extranjero, el pertenecer a un programa de especialidad y los programas de especialidades quirúrgicas se asocian de manera independiente a burnout.(AU)

Introduction: Burnoutis a pathological syndrome characterized by emotional exhaustion, depersonalization and low sense of personal accomplishment. Residents from medical specialties and subspecialties constitute a population at risk for high work overload and interference in personal life. The aim of this study was to evaluate the prevalence of burnout and its associations with sociodemographic variables, in specialty and subspecialty residents of the Pontificia Universidad Católica de Chile (PUC). Methods: An electronic survey was answered by residents of specialty and subspecialty of PUC. It included the "Maslach Burnout Inventory" (which consists of 22 questions divided into 3 dimensions). The points of each dimension were added and burnout was defined as a high score on depersonalization or emotional exhaustion subscales. Statistical analysis included an univariate and multivariate analysis. Results: 415 surveys were answered (response rate 86 percent). 38.3 percent of residents met criteria for burnout, with a percentage of 41.9 percent for specialty residents and 24.1 percent for subspecialty residents. In the subgroup analysis, the highest prevalence was found in surgical specialties (55.3 percent). Foreign residents, medical residency programs (compared to sub specialization programs) and surgical programs were independently associated with burnout (OR 3.8 IC95 percent1.4-10.5, p=0.01; OR 2.3 IC95 percent 1.3-4.1, p<0.01 y OR 1.7 IC95% 1.1-2.7; p=0.02, respectively). There was no independent association between duty hours and burnout (p=0.19). Conclusion: Specialty and subspecialty residents have a high prevalence of burnout. Additionally, foreign residents, participation in a speciality residency (compared to subspecialties programs) and surgical residencies are independently associated to burnout. (AU)