Paola Viviani

Bio: Paola Viviani is an academic researcher from Pontifical Catholic University of Chile. The author has contributed to research in topics: Medicine & Population. The author has an hindex of 17, co-authored 34 publications receiving 1210 citations.

Predictors of nonalcoholic steatohepatitis (NASH) in obese patients undergoing gastric bypass.

Abstract: Background: Nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) are conditions gaining increasing recognition in hepatology as a potential cause of cirrhosis and end-stage liver disease. Obesity is one of the main risk factors. The aims of this study were to determine the frequency of NAFLD in obese patients and to identify variables that predict NASH. Methods: A prospective study was conducted of obese patients undergoing gastric bypass over a 20-month period. Assessment included liver function tests and evaluation of insulin resistance with the homeostatic model assessment (HOMA-IR). Liver biopsy was performed in all patients at the time of surgery. Clinical and biochemical variables were analyzed using a multivariate analysis to identify independent predictors of NASH. Results: 127 consecutive patients were included (62% female, 38% male, mean age 40±11 years, mean body mass index 42±6 kg/m2). Arterial hypertension was present in 52 patients (41%) and type 2 diabetes in 18 (14%). NAFLD was confirmed in 80 patients (63%), 47 (37%) had simple steatosis, and 33 (26%) had NASH. Cirrhosis was found in 2 patients corresponding to 1.6% of the total population. On multivariate analysis, AST >31 (IU/L) (OR 3.38, CI 1.17-9.8) and HOMA-IR >5.8 (OR 4.18, CI 1.39-12.49) independently predicted NASH. Conclusions: NAFLD is highly prevalent in morbidly obese patients. A high proportion of these patients exhibit NASH on histological examination. Insulin resistance represents the main predictor of NASH.

Value of adenosine deaminase (ADA) in ascitic fluid for the diagnosis of tuberculous peritonitis: a meta-analysis.

Abstract: Background and goals Adenosine deaminase (ADA) levels are used for diagnosing tuberculosis in several locations and although many studies have evaluated ADA levels in ascitic fluid. These studies have defined arbitrary cut-off points creating difficulties in the clinical application of the results. The goals of this study are: to determine the usefulness of ADA levels in ascitic fluid as a diagnostic test for peritoneal tuberculosis (PTB) and define the best cut-off point. Study A systematic review was done on the basis of 2 independent searches. We selected prospective studies that included consecutive patients. Diagnosis of PTB had to be confirmed by bacteriologic or histologic methods and ADA levels determined by the Giusti method. Inclusion/exclusion criteria were applied by 2 independent reviewers. A receiver operating characteristic curve was constructed to establish the optimal cut-off point and the likelihood ratios (LRs) estimated using fixed-effect pooled method. Results Twelve prospective studies were found. Four of them met the inclusion criteria and were thus included in the meta-analysis. They included 264 patients, of which 50 (18.9%) had PTB. ADA levels showed high sensitivity (100%) and specificity (97%) using cut-off values from 36 to 40 IU/L. The included studies were homogeneous. Optimal cut-off point was determined at 39 IU/L, and LRs were 26.8 and 0.038 for values above and below this cut-off. Conclusions This study supports the proposition that ADA determination is a fast and discriminating test for diagnosing PTB with an optimal cut-off value of 39 IU/L.

Measuring students' perceptions of the educational climate of the new curriculum at the Pontificia Universidad Católica de Chile: performance of the Spanish translation of the Dundee Ready Education Environment Measure (DREEM).

Abstract: Context: During the last decade a major curriculum reform was carried out at the Pontificia Universidad Catolica de Chile Medical School. The process included changes in curriculum development, staff development and in the infrastructure. However, it is not known how students perceived the climate of their education within the new model. Objectives: To measure students' perceptions of the educational environment of the new curriculum and to evaluate the internal consistency of the 50-item Dundee Ready Education Environment Measure (DREEM) Spanish version questionnaire. Methods: The DREEM Spanish version questionnaire was administered to undergraduate medical students in training years 3, 4 and 5. Internal consistency of the instrument and its subscales were measured with the method described by Cronbach, and the results were expressed with alpha coefficient ranging from 0 to 1. Findings: Responses were received from 297 out of 328 students (90.5%). The 50-item DREEM Spanish version was found highly reliable with an alpha coefficient of 0.91. The subscale with the highest mean score was Academic Self-Perceptions, which indicates students' perceptions of their academic achievements. Mean score of this subscale was 22.3 ± 4.1 corresponding to 69.7% of the maximum score. The lowest mean score was for the Students' Perceptions of their Social Environment: 15.9 ± 4.0 (56.8%). The overall mean score for the 50 items was 127.5 ± 20.9 (63.8% of maximum). Scores observed in students in year 5 were significantly lower for several subscales, including Students' Perceptions of Learning, Students' Perceptions of Teachers, Students' Perceptions of the Learning Atmosphere and Students' Perceptions of the Social Environment, and also lower for the overall mean score (119.3 ± 20.2) compared to scores in years 3 and 4 (128.8 ± 21 and 132.5 ± 19.7, respectively; p Conclusions: The school's educational climate was generally perceived positively by students, although they viewed the school's social environment less favorably. Specific areas identified by students as needing improvement included an overloaded curriculum and inadequate student supports. The DREEM Spanish version proved generally reliable, by internal consistency scores based on ratings by Chilean undergraduate medical students; it should be a useful tool for assessing students' perceptions of the educational environments of other Latin American medical schools.

Increase of Bone Resorption and the Parathyroid Hormone in Postmenopausal Women in the Long-term after Roux-en-Y Gastric Bypass

Abstract: Background The effects of Roux-en-Y Gastric Bypass (RYGB) on bone in the long-term remains unclear. We assessed bone metabolism and bone mineral density (BMD) 1 to 5 years after RYGB.

Systematic review: the epidemiology and natural history of non-alcoholic fatty liver disease and non-alcoholic steatohepatitis in adults.

Abstract: SUMMARY Background Non-alcoholic fatty liver disease (NAFLD) is a common cause of chronic liver disease, and its worldwide prevalence continues to increase with the growing obesity epidemic. This study assesses the epidemiology of NAFLD in adults based on clinical literature published over the past 30 years. Aim To review epidemiology and natural history of non-alcoholic fatty liver disease and non-alcoholic steatohepatitis in adults based on clinical literature published over the past 30 years. Methods An in-depth search of PubMed (1980–2010) was based on five search terms: ‘nonalcoholic fatty liver disease’ OR ‘non-alcoholic steatohepatitis’ OR ‘fatty liver’ OR ‘steatosis’ AND ‘incidence’ [MeSH Terms] OR ‘prevalence’ [MeSH Terms] OR ‘natural history’. Studies of paediatric cohorts were excluded. Articles were categorised by topic and summarised, noting generalisations concerning their content.