This article reviews the most relevant methodological aspects involved in Health Technology Assessment (HTA). Firstly, it addresses the process of defining the research problem (or scoping). Then it explains some specific aspects of systematic reviews of evidence, as well as indirect and mixed comparisons of the effectiveness of interventions. It covers also the methods for economic evaluation in healthcare and the budget impact analysis of interventions. Finally, the paper provides an empirical insight on the methodological emphasis used by HTA agencies around the world, and reflects on the available capacities in our country in the topics discussed.

In the present study, we determined the prevalence of denture stomatitis and its associated factors in patients that use removable denture. These patients come from the prosthetics clinic of the Miraflores Clinic and from the dental clinic of the Universidad Mayor between September 2009 and December 2010. The total of 75 patients with removable dentures were examined, two samples were taken of each patient, one of their palate and other of their prostheses, for performing microbiological studies. The 68% of the patients showed alterations in the palate mucosa subprotesic compatible with stomatitis. 74.6% of patients with denture stomatitis isolated at least one species of Candida, with no meaningful evidence. Removable dental prosthesis substantially affects the appearance of denture stomatitis. When the severity of illness increases the presence of Candida also increases, Candida albicans being the most prevalent in patients with denture stomatitis.

El objetivo de este estudio, fue determinar la prevalencia de estomatitis subprotésica y sus factores asociados en pacientes portadores de prótesis removibles. Estos pacientes pertenecieron al Departamento de Prostodoncia del Consultorio Miraflores y a la Clínica Odontológica de la Universidad Mayor entre Septiembre 2009 y Diciembre 2010. El total de pacientes examinados fueron 75 portadores de prótesis removibles. Se tomaron dos muestras a cada paciente, una proveniente del paladar y otra de su prótesis, con su posterior estudio microbiológico. El 68% de los pacientes presentó alteraciones en la mucosa palatina compatibles con estomatitis subprotésica. En el 74,6% de los pacientes con estomatitis subprotésica se aisló al menos una especie de Candida, no existiendo diferencia significativa. La prótesis dental removible influye notablemente en la aparición de la estomatitis subprotésica. Al aumentar la gravedad de la enfermedad, aumenta la presencia de Candida, siendo Candida albicans la más prevalente en pacientes con estomatitis subprotésica.

The pediatrician holds a close relationship with children and their parents during the first years of life. As such, this professional has regular opportunities to perform screening dental examination in young children and to educate families on preventive oral health. The aim of this study was to assess Chilean pediatricians' knowledge, attitudes and professional experience regarding children's oral health. A survey was responded by 164 pediatricians attending the 50th Chilean Pediatrics Convention. The survey questionnaire was translated and adapted from a national survey for pediatricians designed by the Department of Pediatrics, University of Washington. The face and content validity of the instrument was evaluated through a focus group with Chilean pediatricians. The survey included demographic data, elements related to knowledge about oral preventive therapies, their own role in oral health promotion, their experience to screen oral problems and the barriers to refer patients to the dentist. The results showed that 64% of the respondent pediatricians reported to diagnose dental cavities in preschool children at least once a month. 51.53% agreed with referring children to the dentist from the age of 1, however 55.82% found difficulties to successfully refer children under 2 years old. Only 3% of the respondents answered all knowledge questions correctly. 66.87% never received training in oral health during their pediatrics specialization studies. In spite of the general consensus about the relevance of oral health and the frequent encounter with oral pathologies, pediatricians acknowledge that they do not possess enough knowledge nor referral strategies to participate in their prevention.

El pediatra sostiene una estrecha relación con el niño y sus padres durante sus primeros años de vida, teniendo periódicamente la oportunidadde detectar problemas orales y educar en su prevención. El objetivo de este estudio fue evaluar los conocimientos, actitudes y experiencia profesional de pediatras chilenos en relación a la salud oral infantil. Se aplicó una encuesta a 164 pediatras asistentes al 50 Congreso Chileno de Pediatría. El instrumento fue traducido y adaptado de la encuesta nacional para pediatras de la Universidad de Washington. La validez de fachada y contenido fue evaluada mediante un grupo focal compuesto por pediatras. La encuesta incluyó datos demográficos, aspectos relacionados con su conocimiento sobre terapias preventivas en salud oral, su opinión sobre su rol en promoción de salud oral, su experiencia para detectar problemas orales y barreras existentes al referir pacientes al odontólogo. Los resultados mostraron que el 64% de los encuestados reportaron diagnosticar caries en preescolares al menos una vez al mes. El 51,53% estaba de acuerdo con derivar al odontólogo al niño al año de edad, sin embargo, 55,82% reportó dificultad al referir pacientes menores de 2 años. Sólo 3% respondió correctamente todas las preguntas sobre conocimiento. 66,87% nunca recibió instrucción en salud oral durante su formación como especialista. A pesar que los pediatras asumen que la salud oral es un aspecto importante de la salud general y que se enfrentan frecuentemente a patologías orales, reconocen que no cuentan con los conocimientos y estrategias de derivación oportuna, para participar de la prevención de ellas.

Mucormycosis is an increasingly emerging life-threatening infection and is an important cause of morbidity and mortality in patients with leukemia. We present the case of a 4-year-old boy with an acute lymphoblastic leukemia complicated by severe and prolonged neutropenia during induction chemotherapy, who developed cutaneous mucormycosis of the elbow. Direct microscopy with KOH and the histopathologic observation of the skin revealed fungal hyphae without septations. The cultures were positive for Rhizopus microsporus var oligosporus. The patient was treated succefully with amphotericin B during 40 days, surgical debridement and dermoepidermic graft. Early recognition and prompt intervention with combined medical and surgical treatment may improve the outcome. The most common management strategy in survivors involves a combination of antifungal therapy with amphotericin B and surgical debridement.

La mucormicosis es una enfermedad emergente grave, producida por hongos saprófitos del orden Mucorales, que afecta fundamentalmente a pacientes inmunocom-prometidos. La forma cutánea se origina por inoculación de esporas dentro de la dermis con el subsecuente desarrollo de una lesión tipo ectima, generalmente única y de evolución rápidamente progresiva, por las características angioinvasoras del hongo, que determina amplias zonas de infartos y necrosis en los tejidos. Presentamos el caso de un paciente con cuatro años de edad, con diagnóstico de leucemia linfoblástica aguda, en quimioterapia de inducción, que cursó con neutropenia profunda y prolongada, presentando una lesión cutánea en el codo compatible con ectima gangrenoso. Recibió tratamiento antimicrobiano y antifúngico, asociado a un aseo quirúrgico. El cultivo para hongos demostró crecimiento de Rhizopus microsporus var oligosporus, y la histología concluyó presencia de hifas no septadas. El estudio de extensión descartó compromiso óseo, sinusal y cerebral. Completó 40 días de terapia antifúngica con anfotericina B deoxicolato, evolucionando satisfactoriamente. Posteriormente requirió injerto dermo-epidérmico. Si bien esta patología es infrecuente, debemos sospecharla en pacientes con neoplasias hematológicas, para establecer un diagnóstico etiológico oportuno, ya que el tratamiento contempla el desbridamiento quirúrgico precoz asociado a antifúngicos sistémicos, siendo de elección anfotericina B.

Metal profiles in lake sediments could provide historical environmental information on impacts caused by human activities and natural events, with view to the formulation of effective environmental policies. This paper presents data on sedimentary metal profiles in Laguna Chica de San Pedro (LCSP) lake, located in the Bio Bio Region in Southern Chile, where important industrial activities are concentrated. Sediment properties (organic and inorganic matter, grain size, particle distribution, biogenic silica, Mn/Fe ratio), major (Al, Ca, K, Mg, Ti, Na), trace (V, As, Co, Cu, Zn, Ni, Cr, Pb, Sr), and mobile (Fe, Mn, P, S) elements, as well as mineral profiles (plagioclase, quartz, clays, amorphous material) are presented, up to 65 cm depth. In general, relatively constant concentration profiles are observed in the sedimentary core mid section, for most elements. Most changes in composition are seen at the top (recent industrial period) and bottom (before human intervention) sections. Variable redox conditions, generated by biological activity at the sediment-water interface are likely to account for composition profiles at the sediment-water interface. On the other hand, physical processes seem to be mostly responsible for concentration changes in Pre-industrial sediments. Mineral content profiles, such as plagioclase, clay and quartz, as well as total clay content remain fairly constant in most of the core, showing significant changes at its bottom part. High excess V, As, and S values, especially at the upper sediment, arise as a consequence of redox conditions in the lake. Certainly, such metal enrichment is mainly associated with natural sedimentary matter supply from the watershed

Relato de um caso atípico de infecção fúngica da córnea causada pelo microrganismo Fonsecaea pedrosoi após trauma ocular. Paciente, masculino, estudante de 18 anos, apresentou-se ao Setor de Doenças Externas Oculares do Departamento de Oftalmologia da UNIFESP com úlcera de córnea paracentral de 3,5 x 3,5 mm e aspecto branco-acinzentado com bordas infiltradas, 28 dias após trauma em ocular por vidro. Foi realizado raspado da córnea e o material enviado para análise microbiológica. Foi observado crescimento de colônias em meio de cultura e posteriormente colocadas em solução de lactofenol-azul de algodão. Verificou-se a presença de hifas dermáceas de pigmento escuro, identificado como Fonsecaea pedrosoi. Tratamento foi iniciado com natamicina 5% tópica a cada hora e cetoconazol 200 mg por dia. Subseqüentemente foi substituído pela combinação cetoconazol e anfotericina B. Fonsecaea pedrosoi é uma das principais causas em humanos de micose crônica cutânea, cromoblastomicose, em regiões úmidas tropicais. A combinação de antimicóticos sistêmicos e tópicos pode ser a melhor opção para pacientes no tratamento de cromoblastomicose da córnea.

To report an unusual case of fungus keratitis due to Fonsecaea pedrosoi that developed after corneal trauma. Case report: A 18-year-old male presented with a corneal ulcer in the right eye, 28 days after a trauma with glass fragments. Corneal scrapings were collected for smears and culture. Dematiaceous hyphae were seen on wet mounts of the scrapings and dark pigmented colonies grew repetitively on the culture media; all colonies were identical, and were subsequently identified as Fonsecaea pedrosoi. Treatment was initiated with topical natamycin at one hour intervals, 200 mg oral ketoconazole per day and later changed to a combination of 200 mg ketoconazole and amphotericin B. In humid tropical regions Fonsecaea pedrosoi is one of the primary causes of human chronic cutaneous mycosis, chromoblastomycosis. Combination of systemic and topical antifungal medications may provide the best option for cure in corneal chromoblastomycosis.

Background: The easy access and inappropriate use of antimicrobials led to selection and spread of resistant microorganisms strains. It is imperative to search for new and more effective antimicrobials. One strategy is the screening of metabolites produced by microorganisms found in the environment. Actinomycetes are a potential source of new drugs. Aim: To isolate actinomycetes from sediments of Chilean rivers and lakes and to screen them for antimicrobial activity against reference bacterial strains and pathogenic fungi. Material and Methods: Actinomycetes were isolated from sediment samples, using casein-starch agar. The antimicrobial activity against 3 bacterial species and 7 fungal species was tested using the disc diffusion method. For the extraction of active metabolites, culture broths of antagonistic actinomycetes were extracted with organic solvents followed by testing the antibiotic activity. Results: A total of 62 strains of actinomycetes were isolated, mainly Streptomyces sp (83.9%). Thirty six strains (58.1%) showed antimicrobial activity, mainly against Bacillus subtilis and Candida albicans. Some isolates inhibited a wide spectrum of indicator strains, like LRI 4A strain (Streptomyces sp) that inhibited Bacillus subtilis, Candida albicans and 4 filamentous fungi. Conclusions: Lakes and rivers of Southern Chile are an important reservoir of antagonistic actinomycetes, a potential source of new drugs (Rev Méd Chile 2004; 132: 151-9)

In Chile, three Hantavirus seropositive rodent species (O longicaudatus, A olivaceus and A longipilis) are distributed from the Pacific coast to the Andes mountains and represent nearly 90% of the rodents captured in the Xth Region. Aim: To study the seroprevalence of Hantavirus among captured rodent species and its relationship with the appearance of human cases of pulmonary syndrome. Material and methods: From May 1998 to September 2001, 675 rodents were captured in the region. Serum samples were tested by ELISA for the presence of IgG antibodies against Andes and Sin Nombre virus. Sera from human cases with a suspected Hantavirus infection were analyzed for IgM antibodies against Black Lagoon virus and for IgG antibodies against Andes and Sin Nombre virus. Results: Twenty two of the 675 rodents were seropositive for the virus, 18 O longicaudatus and 4 A longipilis. Regional seroprevalence changed from 2.2% in 1998, 0.0% in 1999, 1.0% in 2000 and up to 7.1% in 2001. A total of 77 positive human cases were studied from 1998 to March 2002. Although there were positive cases in all seasons, data showed a spring-summer seasonal preponderance. A relationship between the flowering of "colihue" bushes and the increased values of rodent abundance, seroprevalence and positive animals was established. Conclusions: A dispersal movement of O longicaudatus to open habitats close to human outdoor activities during the dry season was confirmed (Rev Méd Chile 2003; 131: 169-76)

A retrospective study by means of indirect immunofluorescence was carried out to detect IgM antibodies against Chlamydia pneumoniae and Mycoplasma pneumoniae in seronegative patients for Hantavirus, with characteristics symptoms of atypical pneumonia. The final results indicate that the prevalence of C. pneumoniae reaches 8,6% and M. pneumoniae is equivalent to 17,1% of the patients studied. By this we can be aware of the importance of these agents in our media, and the necessity of having rapid laboratory techniques that allow an opportune differential diagnosis in pulmonary syndrome for Hantavirus and other pathologies that cause similar symptoms, mainly atypical pneumonia

Cat scratch disease (CSD) is the most frequent cause of chronic lymphadenopathy in children and young adults being history of cat or dog contact, scratch or bite in 90 and 60% of patients respectively. Bartonella infections can course from a lymphadenopathy to a systemic disease. Ten per cent of the patients show atypical presentation and 2% present severe disease. We present four cases of atypical CSD in children (11 months to 11 years old) in Valdivia, Chile. The etiology was confirmed by IFI IgG against Bartonella henselae, with titles >1: 256

La enfermedad por arañazo de gato (EAG), es considerada la causa más frecuente de linfoadenopatía benigna crónica en niños y adolescentes. En los casos existe el antecedente de contacto con gatos (90%) y de rasguño y/o mordedura (60%). La infección con Bartonella spp se manifiesta como desde una linfoadenopatía (EAG) a una enfermedad sistémica. El 10% tiene manifestaciones atípicas y 2% presenta complicaciones graves. Debe sospecharse EAG por exclusión de otras etiologías habituales y por el antecedente epidemiológico de contacto y/o rasguño de gato, con o sin lesión de inoculación primaria. Se presentan 4 casos de EAG atípicas en niños del S.S. Valdivia, donde se confirmó el agente por IFI IgG contra Bartonella henselae, con títulos > 1: 256.

Background: The success of orthotopic liver transplantation (OLT) has resulted in its widespread use for different liver diseases. Aim: To report our 8 years experience with adult OLT at Clinica Alemana de Santiago. Patients and methods: In all transplantations done at the center, we recorded patient's overall data and survival, postoperative medical and surgical complications and causes of death. Results: Between November 1993 and September 2001, 51 consecutive OLT were performed in 44 patients (22 females, median age 45 years old). Thirty eight patients presented with chronic and 6 with acute or sub-acute liver failure. Cryptogenic cirrhosis and hepatitis C infection were the most common causes for OLT. Postoperative bleeding and extra-hepatic biliary complications were seen in 17.6 and 21.5% of cases respectively. Acute rejection, bacterial infections, CMV infection or disease and post OLT hemodialysis were the most common medical complications (51, 31, 19.6 and 19.6% of cases respectively). The overall 1 and 5 years survival rates were 80% and 73% respectively. Considering exclusively the last 22 OLT performed since January 1999, the 1 year survival rate has improved to 91%. Conclusions: Liver transplantation in Chile provides a good long term survival with acceptable morbidity, due to a multidisciplinary approach management. The survival rates have improved over the last few years probably due to better surgical techniques, ICU care and immunosuppression. These overall results are comparable with those from other Centers in developed countries (Rev Méd Chile 2002; 130: 779-86)

The Hantavirus Pulmonary Syndrome (HPS) was described in USA in 1993. Cases of HPS have been retrospectively diagnosed by serological techniques back to 1959 in USA and to 1980 in Argentina. In Chile, cases have been reported since 1995. Infection with hantavirus was studied in three family groups who were attended at the Hospital Clínico Valdivia as probable severe cases of atypical pneumonia between February and April 1993. IgG anti hantavirus antibodies with titles >1/6400, were found in 5 of 7 patients. Their relatives were serologically negative. The patients presented different degrees of pulmonary and body damage, hypoxemia, thrombocytopenia and hypoalbuminemia. In some cases, increases in leukocyte counts, in GOT and LDH plasmatic levels and hemoconcentration, were found. The HPS related risk factors found were rurality, farm work surrounding their houses, contact with rodents and their excrements, cleaning of empty rural cottages and warehouses. The presence of HPS since 1993 was established in three family groups living in the province of Valdivia. These findings indicate that in unexplained cases of acute respiratory distress with epidemiological information of contact with rodents, it is necessary to bear the etiology of hantavirus in mind

El síndrome pulmonar por hantavirus (SPH) fue descrito en E.U.A. en 1993. Se notificaron casos en Chile desde 1995. Utilizando serología se han identificado retrospectivamente casos desde 1959 en E.U.A. y 1980 en Argentina. En tres grupos familiares atendidos en el Hospital Regional Valdivia entre febrero y abril de 1993 se encontraron, en un estudio retrospectivo efectuado 5 años más tarde, anticuerpos IgG anti-hantavirus con títulos > 1/6.400, en 5 de 7 pacientes atendidos con el diagnóstico de neumonía atípica - síndrome de distress respiratorio tipo adulto (SDRA) . Sus contactos presentaron serología negativa. El cuadro clínico de estos pacientes se caracterizó por diversos grados de compromiso pulmonar y sistémico, hipoxemia, plaquetopenia, hipoproteinemia e hipoalbuminemia; en algunos, leucocitosis, hemoconcentración, GOT y DHL elevadas. De los factores de riesgo reconocidos para adquirir SPH, encontramos en esta serie: ruralidad, trabajo agrícola en la vecindad del domicilio, contacto con roedores y sus excreciones, limpieza de cabaña o bodegas desocupadas. Se establece retrospectivamente la presencia del SPH en la provincia de Valdivia a partir de 1993 en tres grupos familiares. Los hallazgos hacen necesario tener presente la etiología de hantavirus en casos inexplicados de SDRA con el antecedente epidemiológico de contacto con roedores silvestres

Em vista da escassez de publicações sobre otomicoses no Brasil, foi projetada uma pesquisa para conhecer a incidência, características clínicas, fatores predisponentes e agentes etiológicos da micose. Durante um ano, 22 casos suspeitos foram estudados, 20 dos quais corresponderam à otomicoses. As espécies mais freqüentemente isoladas foram Aspergillus niger (35%) e Candida albicans (20%). O gênero Aspergillus representou 75% dos isolamentos. Os sinais clínicos mais comuns foram prurido e hiperemia (70%), otalgia (65%), hipoacusia (50%). Falta de cerumen (70%), otite crônica (30%), antibioticoterapia prévia e eczema (25%) foram os fatores predisponentes mais relevantes.

In view of the lack of researches on otomycoses in Brazil, we have tried to study their incidence, their clinical characteristics and the predisponent factors During one year, 22 suspected cases were seen, 20 of them corresponded to otomycosis infections. The most frequent species were Aspergillus niger (35%) and Candida albicans (20%). The genus Aspergillus represented 75% of the isolates. Itching and hyperaemia (70%), otalgia (65%), hipoacusia (50%) were the commonest signs. Lack of cerumen (70%) chronic otitis (30%) previous antibiotic therapy and eczema (25%) were the most outstanding predisponent factors.