Scielo RSS <![CDATA[Revista médica de Chile]]> http://www.scielo.cl/rss.php?pid=0034-988720080010&lang=es vol. 136 num. 10 lang. es <![CDATA[SciELO Logo]]> http://www.scielo.cl/img/en/fbpelogp.gif http://www.scielo.cl <![CDATA[<b>Impacto del plan AUGE en el tratamiento de pacientes con infarto agudo al miocardio con supradesnivel ST, en hospitales chilenos</b>]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872008001000001&lng=es&nrm=iso&tlng=es Background: In 2005 the Chilean government started a health care reform (AUGE) that guarantees medical treatment for acute myocardial infarction. Aim: To quantify the impact ofAUGE on the management and inhospital mortality of STEMI in a group of Chilean hospitals. Material and methods: Three thousand five hundred and forty six patients with STEMI from 10 hospitals that perform thrombolysis as the main reperfusion therapy were analyzed. We compared demographic and clinical characteristics, hospital treatments and revascularization proceduresin two periods: before (2,623 patients) and after AUGE implementation (906 patients). Logistic regression was used to assess inhospital mortality according to AUGE in the entire sample and stratified by risk groups. Results: We found no differences in demographic and clinical characteristics between the two groups. During AUGE threre was a significant increase in the use of thrombolysis (50% to 60.5%), which was associated to an increase of hypotension from 29% to 35% (p <0.02) and minor bleedings, from 1.6% to 3.4% (p <0.001). After A UGE there was a significant increase in the use ofbeta blockers (65% to 75%), angiotensin converting enzyme inhibitors (70% to 76%), statins (48% to 58%), and aspirin (96% to 97.5%) (p <0.05). Global inhospital mortality decreased from 12.0% to 8.6% (p <0.003) and from 10.6% to 6.8% (p <0.005) in patients treated with thrombolytics. The adjusted odds ratio for inhospital mortality comparing after and before AUGE, was 0.64 (IC 95%, 0,47-0.86). Conclusions: The implementation ofAUGE has been successful in reducing inhospital mortality of STEMI This has been achieved through a better use of evidence based medicine and reperfusion strategies . <![CDATA[<b>Síndrome hemolítico urémico en Chile</b>: <b>presentación clínica, evolución y factores pronósticos</b>]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872008001000002&lng=es&nrm=iso&tlng=es Background: Hemolytic-uremic syndrome (HUS) is characterized by acute renal failure, microangiopathic hemolytic anemia and thrombocytopenia. Aim: To describe the characteñstics ofpatients with the diagnosis ofHUS in Chile, and to identify the most reliable early predictors oímorbidity and moñality. Material and methods: The clinical records ofpatients with HUS aged less than 15 years, attended between January 1990 and December 2003 in 15 hospitals, were reviewed. Demographic, clinical, biochemical, hematological parameters, morbidity and mortality were analyzed. Results: A cohort of 587 patients aged 2 to 8 years, 48% males, was analyzed. Ninety two percent had diarrhea. At the moment of diagnosis, anuria was observed in 39% of the patients, hypertension in 45% and seizures in 17%. Forty two percent required renal replacement therapy (RRT) and perítoneal dialysis was used in the majoríty of cases (78%). The most frequently isolated etiological agentwas Escherichia coli. Mortality rate was 2.9% in the acute phase of the disease and there was a positive correlation between mortality and anuria, seizures, white blood cell count (WCC) >20.000/mm³ and requirements of renal replacement therapy (p <0.05). Twelve percent of patients evolved to chronic renal failure and the risk factors during the acute phase were the need for renal replacement therapy, anuria, WCC >20.000/mm³, seizures and hypertension. Conclusions: The present study emphasizes important clinical and epidemiological aspeets ofHUSin a Chilean pediatricpopulation. <![CDATA[<b>Resultados del <i>bypass </i>gástrico resectivo en pacientes obesos mórbidos ≤ 18 años y ≥ 65 años</b>]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872008001000003&lng=es&nrm=iso&tlng=es Background: The incidence of morbid obesity is increasing and gastric bypass is the most effective surgical treatment. Aim: To assess the long term results of resection gastric bypass among morbidly obese patients aged less than 18 and over 65 years in terms of weight loss and correction comorbidities. Material and methods: From August 1999 to December 2006, 712 patients with morbid obesity were subjected to open resection gastric bypass. A group of 12 patients, aged less than 18 years and a second group of 8 patients aged more 65 years were selected to prospectively assess weight loss, complications and correction of associated comorbidities. Results: In the first group body mass índex (BMI) decreased from 45±6.7 kg/m² to 27.7±3.2 kg/m², in a follow-up períod of 22.9±8.4 months. All comorbidities disappeared or improved. A single patient (8.3%) had an incisional hernia. Among the second group, BMI decreased from 40.6±5.4 kg/m² to 28.4±4.4 kg/m², in a follow-up períod of 26.6±15.9 months. All obesity comorbidities disappeared. Three patients (37.5%) presented incisional hernias. No patient died or had postoperative complications. Conclusions: In both groups resection gastric bypass was safe, obtained an appropriate weight loss and corrected all associated comorbidities to obesity. <![CDATA[<b>Complicaciones neurológicas en pacientes adultos sometidos a trasplante hepático ortotópico</b>: <b>Experiencia de un centro universitario</b>]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872008001000004&lng=es&nrm=iso&tlng=es Background: Orthotopic liver transplantation (OLT) is the treatment of choice for multiple acute and chronic end-stage liver diseases as well as for selected cases of liver malignancy and ¡iver-site metabolic disorders. Neurological impairment is a major source of morbidity and moñality following OLT. Aim: To describe the incidence and the type of neurological complications occurring in the post-operative period of OLT in patients transplanted in our hospital. Material and methods: Between March 1994 and August 2007, 76 adult patients underwent OLT. Data on incidence, time of onset, and outcome of central nervous system (CNS) complications have been obtained from our program data base and patient charts. Results: Twenty three patients (30.3%) had CNS complications following OLT. The leading complications were immunosuppressive drug-related neurological impairment in nine patients (39.1%), peripheral nerve damage in five patients (21.7%), central pontine myelinolysis in four patients (17.4%), cerebrovascular disease in three (13%) and CNS infection in three (13%). Most CNS events (90%) occurred in the first 2 weeks after OLT. Five patients with neurological complications died (22%). Conclusions: CNS complications occurred in almost one fifth of the population studied, and they had a poor outcome, as previously reported). <![CDATA[<b><i>Variables clínicas y de laboratorio asociadas a la calidad de vida de pacientes brasileños en hemodiálisis</i></b>: <b><i>Estudio de un centro</i></b>]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872008001000005&lng=es&nrm=iso&tlng=es Background: Amongst chronic diseases, end-stage renal disease (ESRD) deserves special attention in the context of health-related quality oflife (HRQOL). ESRD affects quality of Ufe more intensely than heart failure, diabetes, chronic lung disease, arthritis and cáncer In addition, patients who perceive ¡ow HRQOL withdraw from dialysis treatment more commonly Aim: To identify clinical and laboratory variables associated with health-related quality oflife (HRQOL) in hemodialysis (HD) patients. Patients and methods: We included 174 chronic HD patients from a single unit aged 18 years and older who never received a kidney allograft and survived the first three months of treatment. We used the Khan índex to assess comorbidity and the Medical Outcomes Study 36-Item Short Form Health Survey Questionnaire (SF-36) to measure HRQOL. Resulte: Amongst the eight domains of HRQOL, physical role had the lowest score (35.0±43.0) and social function the highest (64.3±27.7). In the multivariate analysis, age was associated with seven of eight domains, excepting bodily pain. Albumin was associated with five of eight domains. Time on dialysis, hemoglobin and calcium-phosphorus product were associated with physical function, bodily pain and vitality, respectively. Conclusions: Age and albumin were the main variables associated with quality life, and the calcium-phosphorus product was associated with a strategic domain: vitality. Attention to albumin and ageing effects, control ofthe calcium-phosphorus product and improvement of physical conditioning are necessary to achieve better HRQOL.<hr/>Antecedentes: La enfermedad renal terminal afecta la calidad de vida relacionada a salud más que la insuficiencia cardíaca, la diabetes, enfermedad pulmonar crónica y cáncer. Los pacientes que tienen una baja calidad de vida, se retiran de los tratamientos dialíticos con más frecuencia. Objetivo: Identificar variables clínicas y de laboratorio asociadas a la calidad de vida relacionada a salud, en pacientes en hemodiálisis crónica. Pacientes y método: Se estudiaron 174 pacientes en hemodiálisis crónica, mayores de 18 años y que nunca hubieran recibido un trasplante renal. Se utilizó el índice de Khan para evaluar comorbilidades y el cuestionario SF-36 (36-Item Short Form Health Survey Questionnaire) para evaluar calidad de vida relacionada a salud. Resultados: De los ocho dominios que comprende el cuestionario, el rol físico obtuvo el puntaje más bajo (35.0±43.0) y la función social, el más alto (64.3±27.7). En el análisis multivariado, la edad estaba asociada con siete de los ocho dominios, exceptuando dolor corporal. La albúmina estaba asociada con cinco de los ocho dominios. El tiempo en diálisis, la hemoglobina y el producto calcio-fósforo se asociaron con función física, dolor corporal y vitalidad, respectivamente. Conclusiones: La edad y albúmina fueron las variables más asociadas a calidad de vida. El producto calcio-fósforo se asoció a vitalidad, un dominio estratégico. Para mejorar la calidad de vida, se debe prestar atención a la albúmina y los efectos del envejecimiento, se debe controlar el producto calcio-fósforo y mejorar la condición física. <![CDATA[<b>Tabaquismo activo y cancer pulmonar</b>: <b>Determinación de fracciones atribuibles por sexo</b>]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872008001000006&lng=es&nrm=iso&tlng=es Background: The association between Lung Cancer and smoking is well documented. However there is less information about the estimation of its attributable fraction and population burden. Aim: To estímate the attributable risk and population attributable risk of smoking among Lung Cancer patients attended in Public Health Services at Santiago. Material and methods: A case control study matched by age was carried out. Crude and adjusted attributable and population attributable risks were estimated, controlling for potential confounders and interaction variables. Results: Mean age for cases was 63 years for women and 67 years for men. Lung Cancer patients had a higher smoking prevalence than controls (64.5% and 39.7% respectively among women; 95.8 and 67.1 respectively among men p <0.01). Heavy smoker proportion was 4 times higher among patients that smoked 5 to 10 years more (women and men respectively, p <0.01) and 3 times more cigarettes per day (p <0.01). Attributable risk for women was 64.4% and 90.4% for men. Population attributable fraction was 41.9% and 86.3% for women and men, respectively. Projecting these estimates to the Chilean population, approximately 1975 new cases per year of Lung Cancer caused by smoking will be diagnosed. Conclusions: Attributable risks of smoking for Lung Cancer are high and significant, even when they are adjusted by confounding variables. <![CDATA[<b>Estudio piloto</b>: <b>costos directos atribuibles al tabaquismo en dos hospitales de Santiago</b>]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872008001000007&lng=es&nrm=iso&tlng=es Background: Tobaceo is the fourth cause of the global burden of disease, accounting for 79.9 million loss of disability-adjusted Ufe years (DALYs) in 2001. In 2002, tobacco-attributable mortality in Chile represented 17% of total mortality. Aim: To estimate the direct cost of tobaceo in Ischemic Heart Disease, Chronic Obstructive Pulmonary Disease and Lung Cáncer, explore patients' disposition to answer a health related expenses questionnaire, valídate the instruments used and determine an adequate sample size for an upcoming study. Material and methods: Socio-demographic and health care related variables were investigated among patients attending two publie hospitais for ischemic heart disease, chronic obstructive pulmonary disease and lung cancer, in a cross-sectional study. Costs were estimated using the national publie health insurance price list and market pnces. Tobacco-attributable fraction was then applied to calcúlate the tobacco-attributable cost ofeach disease. Results: The instruments used were validated. The group of lung cáncer patients was smaller due to increased mortality prior to interview. Lung cancer generated the largest total and attríbutable direct costs. The costs in patients with ischemic heart disease were significantly lower Conclusions: There were some difficulties in the application of the questionnaire to register medication use. The sample size needed in a larger study was calculated for each of the three diseases. We recommend that a definitive study addresses tobacco-attributable direct costs related to chronic obstructive pulmonary disease. <![CDATA[<b>Valores normales de captación de <sup>131</sup>Yodo de 2 y 24 horas</b>]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872008001000008&lng=es&nrm=iso&tlng=es Background: Radiolabeled iodine uptake is a useful tool in the study of thyroid diseases. Aim: To obtain normal values for 131 Iodine thyroid uptake in healthy volunteers. Material and methods: A total of 105 subjects were included (52 males and 53 females), with a mean age of 45 years (range: 20 to 68, evenly distributed in decades). A questionnaire was applied and a clinical examination was performed to rule out endocrine diseases. Serum TSH and anti-thyroperoxidase antibodies were also measured. The oral 131I dose was 5-10 fiCi, and a Thyrad equipment was used for measurements at 2 and 24 h. Results: Mean global iodine uptake was 5.5%±1.8% (range: 2.3-12.0) at 2 h and 16.2±4.8% (range: 6.5-30.1) at 24 h. The values at 2 h among women and men were 6.0±1.8 and 4.9±1.6%, respectively, (p <0.02). At 24 h, the figures were 17.3±4.5 and 15.0±4.9%, respectively (p =0.01). Compared to their younger counterparts, radioactive iodine uptake was lower among volunteers older than 40 years, at 2 h (5.0±1.7 and 6.0±1.8, respectively, p <0.02) and at 24 h (14.9±4.4 and 17.6±4.9%, respectively, p <0.01). Conclusions: Normal thyroid uptake values in adults are influenced bygender and age. Normal thyroid iodine uptake values are slightly higher in females. Iodine thyroid uptake values decrease slightly in subjects aged more than 40years. <![CDATA[<b>Prevalencia de infección cervical por <i>Chlamydia trachomatis </i>en mujeres de la Región Metropolitana</b>]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872008001000009&lng=es&nrm=iso&tlng=es Background: Chlamydia trachomatis is the most common bacterial sexually transmitted infection (STI) worídwide. In women, chlamydia infections are 75% asymptomatic and can lead to pelvic inflammatory disease, infertility, and ectopic pregnancy. Infants exposed to the microorganism at birth also have a high risk to develop conjunctivitis and pneumonía. Aim: To determine the prevalence of C trachomatis in women in the Metropolitan área of Santiago (Chile). Patients and methods: Cervical specimens were collected from 403 women attending three gynecological outpatient settings from Apríl 2003 to June 2005. These included one public hospital (n =100), a prívate medical center (n =268), and a clinic for adolescents (n =35). Mean ages ofeach group of patients were 35.6±8,2, 33.4±8.1 and 16.9±4.2 years, respectively. The diagnosis of C trachomatis was performed by the amplification byPCRofa 517-base pair segment of the cryptic plasmid on specimens extracted by a commercial procedure. Positive specimens were conñrmed by nested PCRs targeting the ompl gene. The presence of vaginal infections and its association with C trachomatis was investigated in a subset of 223 women ofthe prívate center. Residís: C trachomatis was detected in the cervix of 19 out of 403 women, resulting in a prevalence of 4.7%. The distribution of positive cases among different age groups was not significantly different. Women presenting with bacterial vaginosis had a significantly higher prevalence of C trachomatis infection (p <0.01). Conclusions: This study found a high prevalence of C trachomatis among gynecologic patients that should prompt preventive strategies. <![CDATA[<b>Hiperparatiroidismo primario en el adolescente</b>: <b>Caso clínico</b>]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872008001000010&lng=es&nrm=iso&tlng=es We report a 13 year-old mate with a history of multiple fractures and kidney stones. The laboratory showed a hypercalcemia of 11.5 mg/dl, a PTH of 112.6 pg/ml and 24 hour urinary calcium of 571 mg. Bone densitometry showed spine and fémur Z scores of -2.9 and -1.6, respectively, kidney ultrasound showed nephrocalcinosis and a MIBI-SPECT scintigram showed a higher uptake in the ríght lower parathyroid gland. The diagnosis of primary hyperparathyroidism was made and the patient was operated, excising the ríght lower parathyroid gland. After surgery, serum calcium and PTH levels returned to normal values. In children, the proportion of cases with parathyroid hyperplasia is higher than in adults. Therefore, during surgery all four parathyroid glands must be explored. There is also a higher frequency of ectopic adenomas. Family history must be explored to discard the presence of a multiple endocrine neoplasia (MEN I or II), a familial hyperparathyroidism or a syndrome of primary hyperparathyroidism associated to mandibular tumor. <![CDATA[<b>Nefropatía C1q en un paciente de 17 años</b>: <b>Caso clínico</b>]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872008001000011&lng=es&nrm=iso&tlng=es Clq nephropathy (Clq N) is an infrequent disease and only about 100 cases have been reponed. It is defined by a pattern of immunofluorescense (IF) with dominant or co-dominant complement Clq with electrondense deposits in the mesangium, without clinical or serological features of Lupus Nephritis. The most common histopathological findings of ClqN are focal segmental glomerulosclerosis and Minimal Change Disease. We repon a 17 year-old male patient with an isolated selective proteinuría found in a routine study. He had normal renal function and uriñe culture was negative. Serum lipids, liver enzymes an complement were all normal. Serum antinuclear and anti-DNA antibodies, antineutrophil cytoplasmic antibodies (ANCA), HIV, Hepatitis B and C serology, were negative. Renal and abdominal ultrasonography was normal. The histopathological study revealed segmental glomerular sderosis, modérate increase of mesangial matrix, Bowmann capsule adhesions and fucsinophil deposits in mesangium. The IF was positive (dominant) for Clq (+++) and IgA, IgG, IgM, C3++, all of them with a granular mesangial distribution. Ultrastructural findings were pedicelar effacement and paramesangial electrondense deposits. Tubular reticular inclusions (TRI) were not found. Remission of proteinuría was reached after 18 months of treatment with enalapril and losartan. The patient remains with normal renal function. Clinical findings, negative serology for Lupus, light microscopy IFwith dominant positivity for Clq, absence of TRI and paramesangial electrondense deposits in electron microscopy lead us to the diagnosis of ClqN. A poor response to steroid therapy was described in ClqN. Thus it was worthwhile to differentiate it from lupus nephritis, that is responsive to steroids. <![CDATA[<b>Angiosarcoma primitivo de la aurícula derecha en una mujer joven, con respuesta favorable al tratamiento</b>: <b>Reporte de un caso y revisión de la literatura</b>]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872008001000012&lng=es&nrm=iso&tlng=es Primary malignant cardiac tumors are extremely rare, but their associated mortality is very high. The clinical presentation is oñen variable and nonspecific; by the time symptoms appear, the tumor has usually evolved to a large intracardiac and paracardiac mass causing considerable hemodynamic involvement, regional invasión and distant dissemination. We report a 26 year-old female with a right atrium angiosarcoma with a surprisingly favorable outcome at 2 years follow-up after treatment with a combination of neoadjuvant chemotherapy and surgical resection. She presented with chest tightness, shortness of breath at effort, atypical chest pain, palpitations, asthenia, weight loss and profuse perspiration. Physical examination and irnaging diagnostic procedures, identified a pericardial effusion and a pathologic cardiac mass. The diagnosis of a malignant angiosarcoma was suggested afier computed tomography transthoracic and transesophageal echocardiography It was confirmed at surgery by a biopsy followed by histopathology and immunohistochemistry.<hr/>Los tumores cardíacos malignos son extremadamente raros y su mortalidad es muy alta. El cuadro clínico es variable e inespecífico: frecuentemente cuando aparecen síntomas ya existe una gran masa intracardíacayparacardíaca que causa compromiso hemodinámico grave, además de invasión locorregionaly diseminación a distancia. Comunicamos un caso especial de una mujerjoven que tuvo una evolución sorprendentemente favorable después de un tratamiento combinado con quimioterapia neoadyuvante y resección quirúrgica. La paciente presentó opresión precordial, disnea de esfuerzo, dolor torácico atípico, palpitaciones, astenia, baja de peso y sudoración profusa. El examen físico y exámenes complementarios, especialmente de imágenes, identificaron un derrame pericárdico y una masa cardíaca patológica. La tomografía computada y la ecocardiografía, particularmente la transesofágica, sugirieron el diagnóstico de angiosarcoma maligno, que se confirmó en una intervención quirúrgica que incluyó una biopsia con estudios histopatológicos e inmunohistoquímicos. Se discuten las alternativas del diagnóstico y del tratamiento, y se revisan la epidemiología y los recursos terapéuticos actuales en la literatura. Este caso ilustra la utilidad de la ecocardiografía transesofágica, para el diagnóstico de estos tumores y se plantea que el uso de nuevas alternativas quimioterapias asociadas a la extirpación quirúrgica pueden mejorar la sobrevida que, en nuestra paciente, alcanza dos años libre de síntomas. <![CDATA[<b>Adenocarcinoma gástrico treinta y dos años post linfoma gástrico</b>]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872008001000013&lng=es&nrm=iso&tlng=es The association of gastric lymphoma and gastric adenocarcinoma in the same patient is uncommon. We report a 76 year-old male with a previous history of massive upper gastrointestinal bleeding who required a subtotal gastrectomy with Billroth II reconstruction in 1974. Pathology demonstrated a gastric ¡ympho-histiocytic non-Hodgkin's lymphoma. The patient received complementary radiotherapy and was followed with annual endoscopies for 23 years. In 2006, he presented with fatigue. An upper gastrointestinal endoscopy showed an ulcerated and proliferative lesión at the gastric stump. Biopsy demonstrated a gastric adenocarcinoma. Gastric stump resection with lymph node dissection was perfomed. Pathology of the excised specimen showed a moderately differentiated tubular adenocarcinoma of the gastrojejunal anastomoses which infiltrated up to the subserosa. Additionally lymphatic permeations were observed and 10 of the 16 excised lymph nodes were invaded by the tumor. <![CDATA[<b>Diagnóstico y tratamiento de las metástasis encefálicas</b>]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872008001000014&lng=es&nrm=iso&tlng=es Cerebral metastasis occur in 20 to 30 percent of patients with systemic cancer and are the most common type of intracranial tumor. The median survival of untreated patients is one month with a slightly longer survival in those treated with steroids. Patients treated with whole brain radiation therapy survive between 3 to 6 months. In selected cases survival can increase to 10 to 12 months with combination of surgery and radiotherapy or stereotactic radiosurgery alone or associated to radiotherapy. Most brain metástasis arise from lung, breast and melanomas. The most important criteria for selecting patients who will benefit from surgery or stereotactic radiosurgery are a Karnofsky score of 70 or more, systemic control of the cancer and absence of leptomeningeal involvement. Surgery is indicated in patients with a single lesion located in an accessible zone and stereotactic radiosurgery is indicated for lesions up to 3 cm of diameter, and in patients with up to 3 or 4 metastasis, no matter their location. The survival benefit of chemotherapy in brain metastasis has not been demonstrated. <![CDATA[<b>Papel de las enzimas citocromo p450 en el metabolismo de fármacos antineoplásicos: Situación actual y perspectivas terapéuticas</b>]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872008001000015&lng=es&nrm=iso&tlng=es Cytochrome P450 enzymes are very important to metabolize anti-carcinogenic agents. Therefore, understanding the role of these enzymes and their allele variants in the bioactivation or detoxification of drugs could greatiy benefit antineoplastic pharmacotherapy. The aim of thís manuscrípt is to give information about metabohzing enzymes for antineoplastic agents and to relate the current situation in antitumoral pharmacotherapy with recent knowledge about cytochrome P450 enzymes. This is crucial for the future perspectives towards personalized pharmacotherapy. We summarize the role of cytochrome P450 enzymes in the resistance and bioactivation of several antitumor agents, their induction and repression mechanisms and the effect of genetic polymorphisms on variability of drug metabolization. The understanding of genetic variability will help to develop new research Unes on innovative therapeutic possibilities. <![CDATA[<b>Restricción alimentaria y sobrealimentación</b>: <b>Un modelo de la neurociencia afectiva</b>]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872008001000016&lng=es&nrm=iso&tlng=es Some subjects may overeat when they experience anxiety even if they chronically restrict their food consumption. This contradictory behavior is a dysfunctional emotional regulation mechanism, which promotes the development of obesity and eating disorders. We review studies from a research program where alimentary restriction and overeating are conceived under the perspective of affective neuroscience. In this framework, restrained eaters (RE) are descríbed as subjects that are emotionally vulnerable and have dysfunctional emotional modulation strategies. We discuss empine evidence about the influence of motivational systems on alimentary behavior. Electrophysiological observations in RE reveal a self-referential processing of food stimulus as well as dysfunctional processing duríng the differentiation of emotional expressions. We stress the role of emotional education and the creation of psychometríc instruments designed for early detection of restrained eaters. <![CDATA[<b>Semblanza del Profesor Benedicto Chuaqui Jahiatt a 5 años de su muerte (1934-2003)</b>]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872008001000017&lng=es&nrm=iso&tlng=es The present article commemorates the fifth anniversary of the death of Professor Benedicto Chuaqui Jahiatt, a prominent Chilean pathologist at the School of Medicine ofthe Pontificia Universidad Católica de Chile. Professor Chuaqui was well known for his teaching skills, his scientific work with international projections and his humanistic visión of medicine. His publications reflect, his wide spectrum and integrative visión of different disciplines ofboth naturalsciences and¡inguistics. <![CDATA[<b>Los medios de comunicación y los avances biomédicos</b>]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872008001000018&lng=es&nrm=iso&tlng=es The public dissemination of advances in biomedical research and clinical medicine generates several difficulties and problems. Mass media have the responsibility to report accurately and in a comprehensive way, and physicians and researchers mustprovide this information in a timely manner and without bias. Afíer reviewing the ¡iterature related to this subject and discussing some examples of inadequate information in the Chilean context, the authors suggest the foüowing recommendations: journalists should compare and evalúate the information appropñately before its publication, researchers and journalists should work together, reports should inform clearly about the state of the research and every academic institution should avoid reporting publicly preliminary experiences. If these recommendations are foüowed, the general public, physicians, researchers and health care institutions will be benefited. <![CDATA[<b>Análisis crítico de un artículo</b>: <b>La profilaxis primaria de peritonitis bacteriana espontánea disminuye la aparición de síndrome hepatorrenal y mejora la sobrevida en pacientes cirróticos avanzados</b>]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872008001000019&lng=es&nrm=iso&tlng=es Background & Aims: Norfloxacin is highly effective in preventing spontaneous bacterial peritonitis recurrence in cirrhosis, but its role in the primary prevention of this complication is uncertain. Methods: Patients with cirrhosis and low protein ascitic levéis (&lt;15 g/L) with advanced liver failure (Child-Pugh score >9 points with serum bilirubin level >3 mg/dL) or impaired renal function (serum creatinine level >1.2 mg/dL, blood urea nitrogen level >25 mg/dL, or serum sodium level &lt;130 mEq/L) were included in a randomized controlled trial aimed at comparing norfloxacin (35 patients) vs placebo (33 patients) in the primary prophylaxis of spontaneous bacterial peritonitis. The main end points of the trial were 3-month and 1-year probability of survival. Secondary end points were 1-year probability of development of spontaneous bacterial peritonitis and hepatorenal syndrome. Results: Norfloxacin administration reduced the 1-year probability of developing spontaneous bacterial peritonitis (7% vs 61%, P <0.001) and hepatorenal syndrome (28% vs 41%, P 0.02), and improved the 3-month (94% vs 62%, P 0.003) and the 1-year (60% vs 48%, P 0.05) probability of survival compared with placebo. Conclusions: Primary prophylaxis with norfloxacin has a great impact in the clinical course of patients with advanced cirrhosis. It reduces the incidence of spontaneous bacterial peritonitis, delays the development of hepatorenal syndrome, and improves survival. <![CDATA[<b>Diagnóstico y tratamiento de la perforación de colon durante la colonoscopia</b>]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872008001000020&lng=es&nrm=iso&tlng=es Background & Aims: Norfloxacin is highly effective in preventing spontaneous bacterial peritonitis recurrence in cirrhosis, but its role in the primary prevention of this complication is uncertain. Methods: Patients with cirrhosis and low protein ascitic levéis (&lt;15 g/L) with advanced liver failure (Child-Pugh score >9 points with serum bilirubin level >3 mg/dL) or impaired renal function (serum creatinine level >1.2 mg/dL, blood urea nitrogen level >25 mg/dL, or serum sodium level &lt;130 mEq/L) were included in a randomized controlled trial aimed at comparing norfloxacin (35 patients) vs placebo (33 patients) in the primary prophylaxis of spontaneous bacterial peritonitis. The main end points of the trial were 3-month and 1-year probability of survival. Secondary end points were 1-year probability of development of spontaneous bacterial peritonitis and hepatorenal syndrome. Results: Norfloxacin administration reduced the 1-year probability of developing spontaneous bacterial peritonitis (7% vs 61%, P <0.001) and hepatorenal syndrome (28% vs 41%, P 0.02), and improved the 3-month (94% vs 62%, P 0.003) and the 1-year (60% vs 48%, P 0.05) probability of survival compared with placebo. Conclusions: Primary prophylaxis with norfloxacin has a great impact in the clinical course of patients with advanced cirrhosis. It reduces the incidence of spontaneous bacterial peritonitis, delays the development of hepatorenal syndrome, and improves survival. <![CDATA[<b>LA INMOVILIDAD EN</b><b> PACIENTES CON DEMENCIA AVANZADA PUDIESE SER UNA FORMA DE CATATONÍA REVERSIBLE POR LORAZEPAM</b>]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872008001000021&lng=es&nrm=iso&tlng=es Background & Aims: Norfloxacin is highly effective in preventing spontaneous bacterial peritonitis recurrence in cirrhosis, but its role in the primary prevention of this complication is uncertain. Methods: Patients with cirrhosis and low protein ascitic levéis (&lt;15 g/L) with advanced liver failure (Child-Pugh score >9 points with serum bilirubin level >3 mg/dL) or impaired renal function (serum creatinine level >1.2 mg/dL, blood urea nitrogen level >25 mg/dL, or serum sodium level &lt;130 mEq/L) were included in a randomized controlled trial aimed at comparing norfloxacin (35 patients) vs placebo (33 patients) in the primary prophylaxis of spontaneous bacterial peritonitis. The main end points of the trial were 3-month and 1-year probability of survival. Secondary end points were 1-year probability of development of spontaneous bacterial peritonitis and hepatorenal syndrome. Results: Norfloxacin administration reduced the 1-year probability of developing spontaneous bacterial peritonitis (7% vs 61%, P <0.001) and hepatorenal syndrome (28% vs 41%, P 0.02), and improved the 3-month (94% vs 62%, P 0.003) and the 1-year (60% vs 48%, P 0.05) probability of survival compared with placebo. Conclusions: Primary prophylaxis with norfloxacin has a great impact in the clinical course of patients with advanced cirrhosis. It reduces the incidence of spontaneous bacterial peritonitis, delays the development of hepatorenal syndrome, and improves survival. <![CDATA[<b>DR. </b><b>ALEJANDRO GOIC G., PRESIDENTE DE LA ACADEMIA CHILENA DE MEDICINA, ELEGIDO PRESIDENTE DE LA ASOCIACIÓN DE ACADEMIAS DE MEDICINA DE LATINOAMÉRICA, ESPAÑA Y PORTUGAL</b>]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872008001000022&lng=es&nrm=iso&tlng=es Background & Aims: Norfloxacin is highly effective in preventing spontaneous bacterial peritonitis recurrence in cirrhosis, but its role in the primary prevention of this complication is uncertain. Methods: Patients with cirrhosis and low protein ascitic levéis (&lt;15 g/L) with advanced liver failure (Child-Pugh score >9 points with serum bilirubin level >3 mg/dL) or impaired renal function (serum creatinine level >1.2 mg/dL, blood urea nitrogen level >25 mg/dL, or serum sodium level &lt;130 mEq/L) were included in a randomized controlled trial aimed at comparing norfloxacin (35 patients) vs placebo (33 patients) in the primary prophylaxis of spontaneous bacterial peritonitis. The main end points of the trial were 3-month and 1-year probability of survival. Secondary end points were 1-year probability of development of spontaneous bacterial peritonitis and hepatorenal syndrome. Results: Norfloxacin administration reduced the 1-year probability of developing spontaneous bacterial peritonitis (7% vs 61%, P <0.001) and hepatorenal syndrome (28% vs 41%, P 0.02), and improved the 3-month (94% vs 62%, P 0.003) and the 1-year (60% vs 48%, P 0.05) probability of survival compared with placebo. Conclusions: Primary prophylaxis with norfloxacin has a great impact in the clinical course of patients with advanced cirrhosis. It reduces the incidence of spontaneous bacterial peritonitis, delays the development of hepatorenal syndrome, and improves survival.