Scielo RSS <![CDATA[Revista médica de Chile]]> vol. 139 num. 2 lang. es <![CDATA[SciELO Logo]]> <![CDATA[<b>Detección de ADN de parvovirus B19 en donantes de sangre de tres hospitales en Santiago, Chile</b>]]> Background: Parvovirus B19 (B19) is associated with a wide range of diseases in humans, whose severity depends on the immunological and hematological status of the host. It is transmitted mainly through the airway but also by transfusions. Aim: To determine the B19 DNA carrier frequency in a population of volunteer blood donors from three hospitals blood banks in Santiago, Chile, and to determine the viral load in DNA positive cases. Material and Methods: A total of477 serum samples were analyzed. The screening of B19 DNA was carried out by nested polymerase chain reaction (PCR) directed to the non-structural region of the virus (NS1). The viral load in positives cases was quantified by NS1 Real Time PCR. Results: Parvovirus B19 was detected in four samples, rendering a frequency of 1:119. The viral loads ranged from less than 2000 to 5,626 x 10(5) genome equivalents/ml. Conclusions: Parvovirus B19 was present in four of 477 blood bank blood donors from three hospitals in Santiago. <![CDATA[Reemplazo valvular aórtico con prótesis biológica en pacientes mayores de 70 años con estenosis aórtica]]> Background: Aortic valve stenosis is the most prevalent valvulopathy in the elderly, but it is frequently undertreated. Aim: To assess early and long term results of valve replacement with bioprostheses in patients 70 years old or older with aortic stenosis. Patients and Methods: A review of the database of the Cardiovascular Surgery Service of our hospital, for the period 1990-2007, identified 156 patients with aortic valve stenosis, aged 76.7 ± 4.5 years (67% males), that were subjected to an aortic valve replacement with bioprosthesis. Seventy eight (50%) were in functional class III-IV. Six patients had emergency surgery. In 67 patients (43%) coronary artery bypass graft were performed. Long term mortality was ascertained obtaining death records from Chilean death registry. Results: Operative mortality was 3.2% (5 patients). Four patients (2.6%) required a reoperation due to bleeding. The mean follow up was 66 ± 41 months. The survival rate at 1, 3 and 5years was 94%, 88% and 80%, respectively. Forty two patients (27%) were 80years old or older. In this sub-group, 1 patient (2.3%) died during the peri operative period and the estimated survival rate at 1, 3 and 5years was 97%, 92%, and 80%, respectively. Multivariate risk analysis, for the whole group, identified low ejection fraction and concomitant coronary artery bypass graft surgery as predictors of late mortality. Conclusions: Aortic valve replacement for aortic stenosis with bioprostheses in patients 70 years old or older had low perioperative mortality and morbidity and a good long term survival. <![CDATA[Polimorfismo -174 G/C del gen promotor de interleuquina 6 en mujeres con diabetes mellitus tipo 1]]> Background: A polymorphism located in the promoter region (-174 G I C) of interleukin 6 (IL-6) has been linked to early onset of type 1 diabetes (T1D) and increased body mass index (BMI). Aim: To evaluate the possible association of this -IL-6 gene 174 GIC polymorphism with T1D, BMI and metabolic control in T1D patients in a case-control study. Patients and Methods:-174 G I C polymorphisms were analyzed by polymerase chain reaction and restriction fragment length polymorphism in 145 women with T1D and 103 healthy controls. BMI and BMI-Z-scores were tabulated and metabolic control was recorded. Results: There was a higher frequency for the C allele in T1D patients compared with the control group (21% versus 14.1%, p = 0.047). No significant differences in genotype frequencies for the -174 GIC polymorphism of IL-6 gene between patients with T1D and controls, were observed. There were no significant associations with T1D and BMI. Conclusions: A higher frequency of C allele in women with T1D was the only finding in this series, suggesting that the polymorphic variant is not related to weight gain in these patients. <![CDATA[Evaluación de competencias de intubación traqueal mediante un escenario simulado en internos de medicina]]> Background: Chilean medical schools curricula are focused on the acquisition of competencies. Tracheal intubation is considered a terminal competence. Aim: To evaluate the competencies related to airway management including tracheal intubation in undergraduate medical students. Material and Methods: Prospective observational study. Thirty medical students in the sixth year of a seven years undergraduate program (25.2% of the cohort) were randomly chosen and invited to participate in a simulated environment of elective tracheal intubation using a manikin. The students were assessed according to a checklist validated with the Delphi technique and a written self-assessment questionnaire. Results: Seventeen students (57%) accepted to participate, corresponding to 14.3% of the cohort. Tracheal intubation was achieved by 64%, with 60 seconds as the mean time of apnea. Less than half of the students checked the instruments, performed pre-oxygenation or evaluated the airway. Eighty-seven percent of the students said that the current curriculum offers them minimal competencies for airway management in a real clinical situation and all prefer simulated scenarios for the acquisition of clinical skills. Conclusions: The methodology currently used to teach tracheal intubation is not assuring the acquisition of the competencies to the students in this curriculum stage. More effective teaching methods are required, and the use of simulated scenarios can be a useful tool. <![CDATA[Puntaje de Gleason en cáncer de próstata: Correlación de la biopsia por punción y prostatectomía radical]]> Background: Gleason pathological score in prostate cancer is an importantprognostic indicator. However, the concordance between the score of trans rectal needle biopsies and the final score of the surgical piece may be variable. Aim: To analyze the concordance between Gleason scores of trans rectal prostate biopsies and those of the surgical piece obtained after prostatectomy. Material and Methods: Retrospective analysis of 168 pathological records of radical prostatectomies, performed between 1993 and 2009. All these patients had also a trans rectal biopsy performed previously. Patients with less than 12 tissue cylinders obtained during the trans rectal biopsy or incomplete data were not included in this analysis. Results: Sixty eight percent of trans rectal biopsies had Gleason scores that were concordant with those of the surgical piece. The score was higher or lower in 27 and 10% of biopsies, respectively. Conclusions: Gleason scores of trans rectal biopsies and those of the surgical piece were concordant in 68% of cases in this series of pathological records. <![CDATA[<strong>La quemadura eléctrica por alto voltaje es un factor predictor de mortalidad en pacientes "grandes quemados"</strong>]]> Background: Electrical burns are associated with complications and may aggravate burned patients. Aim: To evaluate the effect of electrical burns in mortality and length of stay in a critical care unit for burn patients. Material and Methods: Retrospective analysis of medical records of 182 patients aged 15 to 90 years, admitted to an intensive care unit for burn patients. The length of stay and mortality of 14 patients that suffered electric burns was compared with the features of 168 patients with other type of burns. Results: Patients with electrical burns were younger, had a lower percentage of total body surface burnt and had a lower frequency of inhalatory injuries than their counterparts with other type of burns. Mortality rate among patients with electric or other types of burns was similar (three and 49 patients, respectively). Intensive care unit stay was also similar. A multivariate analysis showed that high voltage electric burns were an independent risk factor for death with an odds ratio of 12 (95% confidence intervals 1.8-79.4). Conclusions: High voltage electric burns are an independent risk factor for death among burn patients. <![CDATA[<strong>Características clínicas de adolescentes de sexo masculino con trastornos de la conducta alimentaria</strong>: <strong>Estudio de casos clínicos</strong>]]> Background: There is a higher prevalence of eating disorders (ED) among adolescent females. These are less common in men and there are clinical differences between genders. Aim: To describe the clinical features of adolescent males with ED. Material and Methods: Review of 38 medical records of male patients with ED seen in an ED Unit in Chile, between 2001 and 2009. Results: Mean age at first medical visit was 14.4 ± 2.2 years. Symptoms appeared 9.5 ± 8.9 months prior to the first visit. Anorexia Nervosa (AN) of the restricting type was diagnosed in 21 patients (55.2%), with a mean weight loss of 11.2 kg ± 9.4 kg. In 37% of patients, there was a past medical history of overweight. All patients either increased or maintained weight during follow up. Sixty three percent had a psychiatric co-morbidity at first visit. After 3 months of treatment, 82% of patients remained in the program. Conclusions: There was a delay in diagnosis of ED in men. The high prevalence of AN found in this group is characteristic of patients recently diagnosed with ED. Overweight could be a precipitating factor. Nearly two thirds of male ED patients had a psychiatric comorbidity. This high prevalence may suggest a susceptibility to develop ED in males. <![CDATA[<strong>Análisis de las inversiones del intrón 1 y 22 y secuenciación del gen <i>F8 </i>para el diagnóstico genético-molecular de hemofilia A en Chile</strong>]]> Background: Hemophilia A is an inherited disorder caused by alterations in factor VIII gene (F8) located on the X-chromosome, the intron 22 inversion being the most common mutation. The rest are predominantly point mutations distributed along this large gene of 26 exons. Aim: To implement a molecular diagnostic test to detect mutations in the F8 gene in Chilean patients with Hemophilia A. Material and Methods: To validate the testing methods, we analyzed samples with intron 22 and intron 1 inversion, and with point mutations previously studied, as well as one subject without Hemophilia. We also studied unrelated Chilean patients with Hemophilia A and their female relatives for carrier testing. Intron 22 and intron 1 inversions were studied by long distance polymerase chain reaction (PCR) and point mutations by sequencing the coding and promoter regions of the F8 gene. Results: The results obtained in all samples used for validation were concordant with those obtained previously. In the Chilean patients, the intron 22 inversion and point mutations previously described were observed. In 6 out of 9 patients with mild Hemophilia A we found the same mutation (Arg2159Cys) in exon 23, which has been described as prevalent in mild Hemophilia A. Conclusions: The analysis of intron 22 and intron 1 inversions, as well as of point mutations in the F8 gene will help us to confirm the diagnosis in patients with severe, moderate and mild Hemophilia A, and also it will allow us to perform carrier testing and to provide better genetic counseling. <![CDATA[Atrofia muscular espinal: Caracterización clínica, electrofisiológica y molecular de 26 pacientes]]> Background: Spinal Muscular Atrophy (SMA) is an autosomal recessive disorder affecting the anterior horn cells of the spinal cord resulting in muscle weakness and atrophy, linked to the homozygous disruption of the survival motor neuron 1 (SMN1) gene. It is the leading genetic cause of infant death. It has been classified into three types based on the severity of symptoms. Type I SMA is the most severe form with death within the first 2 years of life. Type II and III SMA patients show intermediate and mild forms of the disorder. Aim: To describe the clinical and electrophysiological findings of 26 Chilean patients with SMA with molecular confirmation. Patients and Methods: Retrospective multicenter analysis of patients with SMA assessed between 2003 and 2010. The diagnosis was suspected on clinical and electrophysiological criteria. Since 2006 molecular genetics confirmation was implemented in one of our centers. Results: Twenty-six patients between 2 months and 18 years of age at presentation were analyzed; 15 (58%) were males. SMA I, II and III clinical criteria were observed in 4 (15.4 %), 11 (42.3%) and 11 (42.3%)patients, respectively. All had proximal muscle weakness and atrophy. Electromyography showed features of acute denervation or re-innervation with normal motor and sensory nerve conduction. Nine patients required a muscle biopsy. The genetic confirmation of the disease by PCR technique followed by restriction fragment length polymorphism method disclosed the SMN1 gene deletion in all 26 cases. All patients died secondary to respiratory failure, between eight and 14 months of life. Conclusions: An adequate clinical and molecular diagnosis of spinal muscular atrophy will help for a better management of these patients. <![CDATA[<strong>Implementación de 9 indicadores de calidad en un laboratorio hospitalario</strong>]]> Background: Quality indicators are tools used to monitor specific activities within a process and improve it. In the area of clinical laboratories, the National Accreditation Standards for Providers of Health and the ISO 15189 standard recommend the implementation of indicators that monitor the test cycle with emphasis on those that contribute to a safer health care. Aim: To describe the implementation of nine indicators in a hospital clinical laboratory and their measurement during one year. Material and Methods: The indicators implemented and measured were four of the pre-analytical phase (number of rejected samples, times of transport, blood culture contamination and blood cultures inoculated with adequate blood volumes), two of the analytical phase (coherence of Gram stains of blood culture with microorganism cultured and correct results in external quality control surveys) and three of the post-analytical phase (compliance with order to report lapse goals, corrected reports and alert values report). Results: Two indicators of pre-analytical phase did not meet the per determined targets: number of rejected samples and blood cultures inoculated with adequate blood volume. All indicators of the analytical and post analytical phases were within thepre-determined targets. Conclusions: Coordinated work should be initiated especially with the nursing service to correct the two indicators that did not meet the target. The incorporation of quality indicators to monitor critical processes within the laboratory was undoubtedly an opportunity to identify areas for improvement. <![CDATA[Infección de pseudoquiste pancreático por <i>Haemophilus parainfluenzae</i>: Caso clínico]]> We report a 48-year-old male admitted to hospital due to a severe alcoholic pancreatitis. At four weeks of evolution of the acute episode, an abdominal CAT scan showed a fluid collection of 20 cm diameter located in the pancreatic tail and 2 small collections in the head. The patient received several antimicrobials and during the seventh week of evolution, while receiving vancomycin, presented fever. A fine needle aspiration of the cyst revealed the presence of Haemophilus parainfluenzae biotype VIII. The patient was treated with amoxicillin-clavulanic acid and a laparoscopic cysto-gastrostomy, with a good clinical response. <![CDATA[<strong>Granulomatosis linfomatoide cerebral primaria en paciente VIH positivo</strong>: <strong>Caso clínico</strong>]]> We report a 34-years-old male, with a history of hepatitis B and human immunodeficiency virus (HIV) infection that was admitted to the hospital with malaise, weight loss, frontal behavior and chest pain. Imaging studies showed two frontal cortical/subcortical nodules. A stereotactic cerebral biopsy showed reactive gliosis and a prominent atypical angiocentric and angiodestructive lymphoid infiltrate containing large pleomorphic CD20 and EBV-positive cells consistent with Lymphomatoid granulomatosis. Other studies were negative. The patient was lost from follow up. <![CDATA[<strong>Síndrome hematofagocítico</strong>: <strong>Reporte de cuatro casos y revisión de la literatura</strong>]]> Hemophagocytic syndrome (HS) is a severe hyper inflammatory condition whose cardinal symptoms are prolonged fever, cytopenia, hepatosplenomegaly, and hemophagocytosis by activated, morphologically benign macrophages. The clinical course resembles sepsis, sharing similar physiopathological features. We report four patients with the syndrome. A 61-year-old female presenting with fever and pleuritic pain. During the course of the disease, a pancytopenia was detected and a bone marrow aspiration was suggestive of HS. The patient was treated with cyclosporine and steroids with a good response. A 61-year-old male with fever and pancytopenia and a bone marrow aspirate suggestive of HS. The patient did not respond to treatment and died. A 23-year-old male with fever, pancytopenia and positive Hanta virus antibodies. A bone marrow aspirate was suggestive of HS. The patient recovered without any treatment. A 72-year-old male admitted with the diagnosis of pneumonia, that developed a progressive pancytopenia and bone marrow aspirate was suggestive of HS. A bronchoalveolar lavage showed the presence of Acinetobacter baumanii. Despite treatment with methylprednisolone and gammaglobulin, the patient died. Awareness of the clinical symptoms and of the diagnostic criteria of HS is important to start life-saving therapy in time. <![CDATA[Histiocitosis de células de Langerhans pulmonar: Caso clínico]]> Adult pulmonary Langerhans cell histiocytosis (PLCH) is a rare disorder of unknown etiology that occurs predominantly in young smokers, with an incidence peak at 20-40 years of age. In adults, pulmonary involvement with Langerhans cell histiocytosis usually occurs as a single-organ disease and is characterized by focal Langerhans cell granulomas infiltrating and destroying distal bronchioles. We report a 23-year-old asymptomatic male smoker with a non specific interstitial infiltrate found in preventive chest X ray examination. A high resolution chest CT scan showed multiple cystic structures predominating in the upper lobes, with small centrilobular nodules. A transbronchial biopsy showed a lymphocytic lung infiltrate with Langerhans cells. A surgical biopsy confirmed the diagnosis of pulmonary Langerhans cell histiocytosis. After six months of follow up, the patient is in good conditions. <![CDATA[Hemocianinas, una herramienta inmunológica de la biomedicina actual]]> Hemocyanins, the giant oxygen transporter glycoproteins of diverse mollusks, are xenogenic to the mammalian immune system and they display a remarkable immuno-genicity. Therefore they are ideal non-specific immunostimulants to treat some types of cancer. They are used as an alternative therapy for superficial urinary bladder cancer (SBC), that has been traditionally treated with Bacillus Calmette-Guerin (BCG). In contrast to BCG, hemocyanins do not cause side-effects, making them ideal for long-term repetitive treatments. Hemocyanins have also been exploited as carriers to develop antibodies against hapten molecules and peptides, as carrier-adjuvants for cutting-edge vaccines against cancer, drug addiction, and infectious diseases and in the diagnosis of parasitic diseases, such as Schistosomiasis. The hemocyanin from Megathura crenulata, also known as keyhole limpet hemocyanin (KLH), has been used for over thirty years for the purposes described above. More recently, hemoc yanin from the Chilean mollusk Concholepas concholepas (CCH) has proved to be a reliable alternative to KLH, either as carrier protein, and as a likely alternative for the immunotherapy of SBC. Despite KLH and CCH differ significantly in their origin and structure, we have demonstrated that both hemocyanins stimulate the immune system of mammals in a similar way by inducing a potent Thl-polarized cellular and humoral response. <![CDATA[<strong>Estado actual en el tratamiento de la enfermedad de Chagas</strong>]]> Efficient drugs against Chagas' disease must have an effect on the amastigote forms or intracellular reproduction elements of Trypanosoma cruzi (T. cruzi). Trypomastigote and epimastigote forms derive from the former and their response to medications is less marked. The only drugs used in humans are nifurtimox (NF) and benznidazole (BNZ). Other useful medications are allopurinol and itraconazole. NF acts producing free radicals and BNZ inhibits the synthesis of macromolecules. There is consensus that Chagas' disease must be treated in all its periods, since T.cruzi DNA is detected by polymerase chain reaction in chronic cases, even when microscopy is negative. The pharmacological treatment modifies the natural evolution of the disease. It also helps to solve a public health problem, considering that there is a high number of subjects with Chagas' disease. Subjects with chronic chagasic cardiomyopathy with terminal heart failure are the only cases without indication for treatment. Due to the digestive and skin secondary effects of the drugs, treated patients must be controlled clinically and with complete blood counts and hepatic proiles before, during and after the therapy. Approximately 30% of patients will experience secondary effects. Children have a better tolerance to the drugs. Congenital or acquired acute, intermediate and chronic cases should be treated. <![CDATA[Transmisión de la enfermedad de Chagas por vía oral]]> The traditional transmission pathways of Chagas' disease are vectorial, transfusional, transplacental and organ transplantation. However, oral transmission is gaining importance. The first evidence of oral transmission was reported in Brazil in 1965. Nowadays the oral route is the transmission mode in 50% of cases in the Amazon river zone. Oral infection is produced by the ingestion of infected triatomine bugs or their feces, undercooked meat from infested host animals and food contaminated with urine or anal secretion of infected marsupials. Therefore travelers to those zones should be advised about care to be taken with ingested food. In Chile, this new mode of transmission should be considered in public health policies. <![CDATA[<strong>Manejo paliativo del cáncer de vesícula biliar irresecable o metastásico</strong>: <strong>Conclusiones del Consenso Latinoamericano de Manejo del Cáncer de Vesícula Biliar</strong>]]> Gallbladder cancer is a rare disease in Western developed countries, but it is a highly prevalent and lethal disease in Chile and other countries in Latin America. No randomized controlled trials have been performed in gallbladder cancer to establish standard treatments. We therefore performed the first Latin American consensus meeting for the management of gallbladder cancer. In this article we present the conclusions of the panel of experts for the palliative treatment of unresectable or metastatic gallbladder cancer based on a review of the literature, the discussion of the participating experts and the opinion of the assistants. The topics reviewed included: 1.- Gallbladder Cancer and Cholangiocarcinoma -are they the same disease?; 2. - Palliative Chemotherapy: Indications, Drugs and Schedules; 3. - Palliative Radiotherapy; 4.- Palliative Surgery; 5.-Management of Malignant Biliary Obstruction. <![CDATA[<strong>Labio leporino en la terminología biomédica</strong>]]> Gallbladder cancer is a rare disease in Western developed countries, but it is a highly prevalent and lethal disease in Chile and other countries in Latin America. No randomized controlled trials have been performed in gallbladder cancer to establish standard treatments. We therefore performed the first Latin American consensus meeting for the management of gallbladder cancer. In this article we present the conclusions of the panel of experts for the palliative treatment of unresectable or metastatic gallbladder cancer based on a review of the literature, the discussion of the participating experts and the opinion of the assistants. The topics reviewed included: 1.- Gallbladder Cancer and Cholangiocarcinoma -are they the same disease?; 2. - Palliative Chemotherapy: Indications, Drugs and Schedules; 3. - Palliative Radiotherapy; 4.- Palliative Surgery; 5.-Management of Malignant Biliary Obstruction.