Clostridium difficile Infection: A Worldwide Disease

Clostridium difficile, an anaerobic toxigenic bacterium, causes a severe infectious colitis that leads to significant morbidity and mortality worldwide. Both enhanced bacterial toxins and diminished host immune response contribute to symptomatic disease. C. difficile has been a well-established pathogen in North America and Europe for decades, but is just emerging in Asia. This article reviews the epidemiology, microbiology, pathophysiology, and clinical management of C. difficile. Prompt recognition of C. difficile is necessary to implement appropriate infection control practices.

Fiebre por virus del Nilo Occidental ¿Otra patología emergente relacionada con el cambio climático? / West Nile fever virus. Another emerging disease linked to climate change?

La Fiebre del Nilo Occidental (FNO) es producida por un arbovirus (familia Flaviviridae, género flavivirus) y transmitida por mosquitos Culex. En los '50 se detectó en Israel, Egipto e India, y en 1974 en Sudáfrica. Luego en Argelia (1994), Rumania (1996), República Checa (1997), Rusia (1999) y en EE.UU. (1999), notificados al CDC desde entonces, 24.716 casos con 983 fallecidos. En el 2012 lleva afectando a 3.545 personas con 147 fallecidos. En la Unión Europea (23/8/2012) se notificaron 91 casos (37 confirmados). En Grecia los casos han ascendido a 86. En países vecinos a la UE se notificaron 143 casos. El virus se ha diseminado a Canadá, América Central y el Caribe, afectando las Islas Caimán, Jamaica, República Dominicana, México, Puerto Rico y Cuba. Argentina, sin antecedentes hasta marzo de 2006, confirmó en Córdoba la infección en un hombre y otros 3 en el Chaco. En abril de ese año se confirmó la muerte de 2 caballos en SA de Areco (Buenos Aires), 1 en Entre Ríos y en el 2010 otro equino en Córdoba. Las aves infectadas por hembras de Culex migran a Centroamérica y América del Sur, transmitiendo el virus a especies de vertebrados (mascotas; animales de granja -caballos- y el hombre). El virus puede infectar a otros seres humanos por transfusiones, trasplantes de órganos, etc. No se transmite de persona a persona. Clínicamente se presenta con un cuadro febril o con compromiso neurológico. Los factores de riesgo son variados (HIV/SIDA, trasplante de órganos, quimioterapia, embarazo, etc). La prevención es la lucha contra el mosquito. La fumigación es un recurso útil. Las aguas estancadas donde se reproducen los mosquitos deben drenarse. Los cambios climáticos ocasionan importantes consecuencias para la salud humana con multiplicación de vectores infectantes. Los EE.UU. han tenido este año un invierno suave y un verano caluroso...

The FNO is caused by an arbovirus (family Flaviviridae, genus Flavivirus) and transmitted by Culex mosquitoes. In the 50 was detected in Israel, Egypt and India and in South Africa in 1974. Then in Algeria (1994), Romania (1996), Czech Republic (1997), Russia (1999) and the USA (1999), reported to the CDC since then, 24,716 cases with 983 deaths. In 2012 carries affecting 3.545 people with 147 deaths. In the European Union (23/08/2012) 91 cases were reported (37 confirmed). In Greece’s case amounted to 86. In neighboring countries the UE 143 cases were reported. The virus has spread to Canada, Central America and Caribbean, affecting the Cayman Islands, Jamaica, Dominican Republic, Mexico, Puerto Rico and Cuba. Argentina shows no background until March 2006, confirmed in Cordoba infection in a man and another three in Chaco. In April of that year confirmed the death of two horses in San Antonio de Areco (Buenos Aires), one in Entre Ríos and in 2010 another horse in Cordoba. Birds infected Culex females migrate to Central and South America, transmitting the virus to vertebrate species (pets, farm animals, horses, and man). The virus can infect humans for transfusions, organ transplants, etc. It is not transmitted from person to person. Clinically presents with a fever or neurological compromise. Risk factors are varied (HIV / AIDS, organ transplants, chemotherapy, pregnancy, etc). Prevention is the fight against the mosquito. Fumigation is a useful resource. The stagnant water where mosquitoes breed, should be drained. Climate changes cause significant consequences to human health, with infective vector multiplication. The US has had this year a mild winter and a hot summer. Mankind will become aware of the damage that involves not observe regulatory mitigation measures and environmental pollution. Only a commitment to protecting the environment is everyone’s future hope. We will address other emerging pathology related to climate change...

Epidemiologia da esclerose lateral amiotrófica - Europa/América do Norte/América do Sul/Ásia: discrepâncias e similaridades: revisão sistemática da literatura / Epidemiology of amyotrophic lateral sclerosis - Europe/North America/South America/Asia: discrepancies and similarities: systematic review of the literature

A esclerose lateral amiotrófica é uma doença neurodegenerativa de causa desconhecida, que afeta principalmente os neurônios motores da medula espinhal, tronco cerebral e do encéfalo.No Brasil, há poucos dados disponíveis epidemiológicos da ELA, principalmente nos aspectos de distribuição por gênero, tempo do início da sintomatologia, até o diagnóstico. O presente estudo tem o objetivo de apresentar uma revisão sistemática da literatura indexada sobre incidência, prevalência, forma de apresentação e acometimento inicial da doença, taxa de mortalidade, epidemiologia da ELA no Brasil e em outros países, definida pelos critérios de EL Escorial (WFN, 1998). Foram selecionados 10 artigos, publicados na língua inglesa, de 1982 a 2008, com estudo retrospectivo, observacional, através de busca nas bases de dados por índice, título, assunto, usando combinações de palavras-chave inglesas, visando estudos com pacientes avaliados em centros de referência. Nos trabalhos devidamente tabulados foi aplicado o critério Oxman & Guyatt (1991) para qualificar, sem, entretanto ter intenção de exclusão. Os estudos mostram discrepâncias nas variações em relação à taxa de incidência nas várias regiões do mundo, maior na Ilha de Guam (3,9/100.000 habitantes) e menor na China (0,3/100.000 habitantes). A média de idade de acometimento é menor no Brasil, com 52 anos, mostrando discrepância em relação aos outros países que variam de 59 a 65 anos.A similaridade refere-se ao sexo, com maior prevalência nos homens do que nas mulheres e sintoma inicial com fraqueza muscular assimétrica.

Amyotrophic lateral sclerosis is a neurodegenerative disease of unknown cause, which mainly affects the motor neurons of the spinal cord, brain stem and of the brain. In Brazil, there is few available epidemiological data on ALS, mainly about gender distribution, time of beginning of the symptoms, as well as diagnosis. The present study has as objective to present a systematic review of the indexed literature on incidence, prevalence, form of presentation and initial symptoms of the disease, rate of mortality, epidemiology of ALS in Brazil and other countries, as defined with the EL Escorial criteria (WFN, 1998). Ten articles were selected, published in the English language between 1982 and 2008, with retrospective, observational study, through search in databases for index, heading, subject, using combinations of English keywords, aiming at studies with patients evaluated in reference centers. In the tabulated works, the Oxman & Guyatt (1991) criterion was applied to characterize, but without exclusion intention. The studies show discrepancies in the variations related to the rates of incidence in various regions of the world, mostly in the Island of Guam (3.9/100.000 hab) and less in China (0.3/100.000 hab). The average age of at the beginning is smaller in Brazil, with 52 years, displaying discrepancy in relation to the other countries where it varied from 59 to the 65 years. The similarity is related to the gender, with greater prevalence in the men than in the women, and in relation to initial symptom, with asymmetrical muscular weakness.

Lesão pulmonar aguda associada à transfusão / Transfusion-related acute lung injury

Lesão pulmonar aguda associada à transfusão (transfusion-related acute lung injury, TRALI) é uma complicação clínica grave relacionada à transfusão de hemocomponentes que contêm plasma. Recentemente, TRALI foi considerada a principal causa de morte associada à transfusão nos Estados Unidos e Reino Unido. É manifestada tipicamente por dispnéia, hipoxemia, hipotensão, febre e edema pulmonar não cardiogênico, que ocorre durante ou dentro de 6 h, após completada a transfusão. Embora o exato mecanismo não tenha sido totalmente elucidado, postula-se que TRALI esteja associada à infusão de anticorpos contra antígenos leucocitários (classes I ou II ou aloantígenos específicos de neutrófilos) e a mediadores biologicamente ativos presentes em componentes celulares estocados. A maioria dos doadores implicados em casos da TRALI são mulheres multíparas. TRALI, além de ser pouco diagnosticada, pode ainda ser confundida com outras situações de insuficiência respiratória aguda. Um melhor conhecimento sobre TRALI pode ser crucial na prevenção e tratamento desta severa complicação transfusional.

Transfusion-related acute lung injury (TRALI) is a serious clinical syndrome associated with the transfusion of plasma-containing blood components. Recently, TRALI has come to be recognized as the leading cause of transfusion-related death in the United States and United Kingdom. This complication typically presents as shortness of breath, hypoxemia, hypotension, fever and noncardiogeneic pulmonary edema, all occurring during or within 6 h after transfusion. Although the mechanism of TRALI has not been fully elucidated, it has been associated with human leukocyte antigen antibodies (class I, class II or neutrophil alloantigens) and with biologically active mediators in stored cellular blood components. Most of the donors implicated in cases of TRALI are multiparous women. Rarely diagnosed, TRALI can be confused with other causes of acute respiratory failure. Greater knowledge regarding TRALI on the part of clinicians could be crucial in preventing and treating this severe complication of blood transfusion.

Cost effectiveness of cervical cancer screening among Chinese women in North America.

BACKGROUND: Chinese North American women have high invasive cervical cancer rates and low screening rates. The cost-effectiveness of strategies to improve Pap testing rates for Chinese women living in Seattle, Washington and Vancouver, British Columbia was examined. OBJECTIVES: To calculate the costs and cost-effectiveness of implementing two strategies to motivate women to obtain a Pap smear. RESEARCH DESIGN: A three-armed randomized, controlled trial was conducted. Women in each of two interventions (high-intensity outreach and low-intensity mailing intervention) were compared to a group of women who received usual care. MEASURES: Costs were captured via a group discussion of costs, accounting records, sampling of staff time logs, and estimation of costs and task times. Effectiveness was measured as the proportion of women in each intervention arm who reported receiving a Pap smear since the trial began. Cost-effectiveness was calculated as the incremental cost of screening each additional woman between an intervention arm and the control arm. RESULTS: A greater percentage of women who received the outreach intervention had a Pap test than women who received mailed materials or women who were in the usual care arm. The intent-to-treat cost for each additional woman to be screened for a Pap test was $415 in the Outreach arm and $676 for the Direct Mailing arm. The outreach worker intervention, though more expensive overall, was more cost-effective than the mailing intervention. CONCLUSIONS: Outreach intervention is cost-effective for sponsors and should be considered as a strategy to motivate Chinese women living in North America to seek cervical cancer screening.

Situación de la salud mamaria en el mundo y en Latinoamérica en particular

El cáncer de mama es el cáncer más común entre las mujeres en el mundo y es la causa más frecuente de muerte por cáncer en la mujer. Se reportan tasas de incidencia y mortalidad de este cáncer en el continente americano. La práctica clínica, en países con recursos limitados, con relación al cáncer de mama, puede obligar a los médicos a tomar decisiones contrarias a su conocimiento y a lo que indican las guías clínicas internacionales. El desarrollo de los métodos de diagnóstico y de tratamiento alcanzado en los países ricos, no necesariamente se puede trasladar a los países más pobres. En 2002 se creó la Iniciativa Global para la Salud Mamaria, que es una alianza internacional la cual ha desarrollado guías clínicas basadas en evidencia para países con recursos limitados, con el propósito de colaborar en mejorar la calidad de la atención de las enfermedades de la mama. La última revisión de dichas guías fue publicada en 2005 y en octubre del 2007 se realizará una nueva reunión cuyos pasos estarán dirigidos a la implementación programática de éstas en los países con recursos limitados.

Dinámica espacio-temporal de organismos precursores de marea roja en la costa Pacífica de América del Norte y Centroamérica / Spatial-temporal dynamics of red tide precursor organisms at the Pacific coast of North and Central America

La región costera del Pacífico de Centro y Norte America ha sido afectada de manera frecuente por fenómenos que se denominan proliferaciones algales nocivas o en inglés, "Harmful Algal Blooms" (HAB). A pesar de la gran cantidad de efectos en la salud pública, las actividades económicas y el medio ambiente, aún existe una abrumadora carencia de información en el tema. Esto no permite establecer si las causas principales de este evidente aumento en el número e intensidad de los eventos son naturales o antropogénicas. La incrementada utilización de las zonas costeras para actividades humanas encuentra paralelo en el denominado cambio climático, lo que dificulta discriminar entre la posible influencia de estos dos fenómenos. Series de datos de larga duración en regiones reducidas, así como las observaciones esporádicas realizadas cuando se presenta algún evento, nos permite comparar regímenes climáticos, condiciones geográficas, disponibilidad de nutrientes (incluyendo la eutroficación) y parámetros oceanográficos que promueven o permiten el desarrollo y mantenimiento de las proliferaciones, haciendo evidentes cambios drásticos en la biodiversidad y la biogeografía de los organismos productores de HAB

The Pacific coast of Central and North America has long been and still is impacted by the flourishing of microalgal populations known as Harmful Algal Blooms (HABs). The organisms that have caused recent HABs episodes in the region are among others, Gymnodinium catenatum, Pyrodinium bahamense var. compressum, and recently Cochlodinium cf. catenatum. In spite of the accumulated effects on the human health, the economic activities and the environment, scarce information is available on the subject. The augmented use of coastal zones for human activities is also paralleled by increased awareness of global climate changes. Thus, it is not an easy task to discriminate anthropogenic or natural phenomena, or both, as the major driving forces. The long-term data sets available for limited regions, as well as some sporadic observations during notorious blooms, allowed us to discriminate major changes in the biodiversity and biogeography of HAB organisms. Main changes refer to number of events, covered area, duration and frequency, number of blooming species and appearance of not previously reported harmful taxa. The variables more clearly related to these dynamic phenomena, seems to be sea surface temperature and wind force, but it is not yet possible to weight their contributions. The participation of rain is not fully evaluated to date. The collaborative communication among small-budget monitoring operations in the region allowed to "pass the voice" about peaking concentrations of HAB organisms, diminishing the risk of poisoning

Diagnóstico molecular de Enterobius vermicularis (Lannaeus, 1758) em populações pré-históricas: análise da região intergênica do gene ribossomal 5S RNA e do gene SL 1 RNA / Molecular diagnosis of Enterobius vermicularis (Lannaeus, 1758) in prehistoric populations: analysis of the intergenic region of the ribossomal gene 5S RNA and gene SL 1 RNA

As análises de DNA antigo (aDNA) recuperado de espécimes arqueológicos têm revolucionado áreas das Ciências especialmente na evolução humana e na origem das doenças humanas. Estudos paleoparasitológicos têm mostrado a presença do parasito Enterobius vermicularis em coprólitos de populações antigas das Américas. Até agora o diagnóstico de E. vermiculares em restos arqueológicos depende do exame microscópico. O propósito deste trabalho foi desenvolver uma abordagem metodológica para a recuperação de aDNA e o diagnóstico molecular de E. vermicularis a partir de coprólitos humanos. Propomos o diagnóstico molecular usando como alvo a região intergênica do gene ribossomal 5S RNA de E. vermicularis. Esta estratégia foi analisada quanto a sua especificidade e sensibilidade em parasitos recuperados de amostras fecais e em coprólitos experimentais...Cinqüenta e uma amostras fecais coletadas de pacientes de distintas regiões geográficas do Brasil, e positivas microscopicamente para diversos enteroparasitos incluindo 24 para E. vermicularis fizeram parte deste estudo. O diagnóstico molecular, considerando 420pb da região intergênica do gene 5S rRNA de E. vermicularis identificou 20 das 24 amostras positivas microscopicamente para o parasito, e quando a região de 198pb foi considerada, 100 por cento das amostras analisadas positivas pela análise microscópica, inclusive amostras co-infetadas, foram positivas. A PCR da de 198pb foi sensível para diagnosticar E. vermicularis em amostras fecais com apenas um único ovo do parasito. Os métodos de polimerização reconstrutora e de Nested PCR previamente aplicados em coprólitos experimentais mostraram se úteis na recuperação de aDNA de E. vermicularis em 9 amostras de coprólitos do total de 27 amos5S rRNA de 9 amostras fecais de distintas regiões do Brasil e 7 de coprólitos da América do Norte e da América do Sul, revelou um alto grau de conservação nesta região e a presença do gene SL1 RNA. Nós sugerimos a estrutura secundária do gene SL1 de E. vermicularis, a qual é similar à estrutura modelo de três hastes-alças, e com as mesmas peculiaridades que, em outros organismos são essenciais para a reação de trans-splincing. Pela primeira vez é demonstrada a recuperação de seqüências de aDNA de E. vermicularis provenientes de restos arqueológicos. O diagnóstico molecular específico e sensível para o parasito e a identificação da seqüência e estrutura secundária do gene SL1 RNA de E. vermicularis, também são resultados inéditos.

Diphyllobothriasis: update on human cases, foci, patterns and sources of human infections and future considerations.

Diphylobothriasis is a well documented disease of humans. On a world scale new infections are reported regularly, especially from Russia and parts of Japan. Globally, new species have been discovered and the etiology of the disease may be changing. Human infections appear to be in decline but it is not clear if the sources of infection are also in decline or if public health awareness has improved. In North America there has been a decline in human cases while in South America an increase in reports from fish, especially salmonids suggests high levels in these fish species. The history of human infections of Diphyllobothrium latum is primarily associated with the consumption of the northern circumpolar distributed pike and percids and is often considered a parasite of humans only. Indeed some researchers believe that D. latum was introduced to North America by northern European immigrants. The more benign human infections of D. dendriticum appears to be primarily associated with salmonids and coregonid fishes and fish eating birds. Although the early cases of diphyllobothriasis in the 1930s in North America came from fish originating in Lake Winnipeg, Manitoba, there was general belief that it was declining in fish populations and therefore of little significance to humans in the area. However, high levels of a plerocercoid in the flesh of walleyes and pike led to rejection of commercially harvested walleye and pike in Manitoba and northern Ontario, Canada, and a financial loss to Aboriginal fishers. D. latum is widely distributed in fishes of Manitoba and is infective to humans where it is not pathogenic and has a life span up to 4.5 years. The distribution and potential infection routes has not changed in a century and is still well established in natural hosts in the boreal regions of North America. Evidence is building for an old pre-European presence in North America, involving the Beringian land bridge and later involvement of susceptible hosts (northern European immigrants).

Distribuiçäo geográfica e dispersäo alti-latitudinal de alguns gêneros e espécies da tribo Triatomini Jeannel, 1919 (Hemiptera, Reduviidae, Triatominae) / Geographical distribution and alti-latitudinal dispersion of some genera species of the tribe Triatomini Jeannel, 1919 (Hemiptera, Reduviidae, Triatominae)

With the currently known distribution of genera and species of the tribe Triatomini Jeannel, 1919, maps and diagrams were prepared, showing the geographical area occupied by the species and their respective dispersion in grades of latitude and altitude. Two general are not treated: Panstrongylus Berg, 1879, already published and Triatoma Laporte, 1832, that is being published partially in several articles. Genus Eratyrus Stal, 1859, has two species, while Dipetalogaster Usinger, 1939, Mepraia Mazza, Gajardo & Joerg, 1940, Paratriatoma Barber, 1938 and recently created genus Hermanlentia Jurberg & Galväo, 1997, have only one each. The study of these maps and diagrams permits a better knowledge about some ecological requirements of Chagas's disease vectors and detects gaps in the geographical distribution, where the species were nor found but probably they could be prevalent.

Frequency of various congenital heart diseases: analysis of 3790 consecutively catheterised patients.

A retrospective analysis of 3790 consecutive patients with congenital heart disease (CHD) who underwent haemodynamic and angiographic studies at Sri Jayadeva Institute of Cardiology, Bangalore, from April 1981 to April 1994 has been done. The incidence of various CHD has been compared with that in other series from Asian and Western countries. Out of 6985 patients who underwent haemodynamic studies, 3790 had CHD (54.3%). Approximately 63 percent (2386) of these cases had shunt lesions like atrial septal defect (ASD), ventricular septal defect (VSD) and patent ductus arteriosus (PDA). Among them, 15 percent (367) had pulmonary arterial hypertension of various grades. The overall incidence of pulmonary arterial hypertension is higher than that reported in the Western literature. Corrective surgery was done in approximately 63 percent of cases. Ethnic differences in the incidence of CHD were found in this study when compared to the Eastern and Western literature. Congenital aortic stenosis and coarctation of aorta were less common compared to Western countries and Tetralogy of Fallot was less common compared to Eastern countries.

Cancer epidemiology: substance and methods

Cancer epidemiology is the scientific discipline that studies the occurrence of neoplastic diseases in man, their risk factors and how they are distributed in populations. Cancer epidemiology also encompasses the study of clinical outcomes in human cancer, such as disease recurrence, second tumors, and death, as well as of their determinants, the so-called prognostic factors. Well accepted discoveries from epidemiologic investigations coupled to experimental evidence from other disciplines form the mainstay of cancer prevention, e.g., the role of tobacco smoking, diet, and environmental exposures, and that of screening. For a long time, epidemiologists have held the belief that tumors do not contain traces of the carcinogens that caused them. This belief, product of the inadequate laboratory tools of the past, has reflected on the "black box" nature of much of the epidemiologic research on cancer. Recent progress in allied scientiric fields such as, molecular and cell biology, and immunology, has provided a promising set of tools for the study of cancer causes and prognostic factors. Use of these tools in epidemiology has afforded for the first time the opportunity to probe more intimately the mechanisms of carcinogenesis and clinical progression.